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Pearson,W. H. WA-RD 614.1 Protocols for Evaluation of Upstream Passage of Juvenile Salmonids in an Experimental Culvert Test Bed 2005 WSDOT
Abstract:
The Washington State Department of Transportation (WSDOT) and its partner agencies developed a research program to design new and retrofit culverts. The goal of this program is to identify culvert bed configurations, designs, and associated hydraulic conditions that allow successful movement of juvenile salmonids upstream, while safely passing water, sediment, and debris downstream. WSDOT, in cooperation with the Washington Department of Fish and Wildlife (WDFW), constructed a culvert test bed at the WDFS's Skookumchuck Hatchery in western Washington State. Battelle conducted experiments to establish protocols for future research on bed conditions, culvert shape, etc. This technical report describes various protocols, such as time of day, duration of test, and density of test fish, and provides hydraulic and biological characterizations of a baseline culvert.

Authors:
Pearson,W. H., Richmond,M., Johnson,G., Sargeant,S. L.

Keywords:
agencies, condition, culvert, culvert passage, culvert test bed, culverts, density, design, developed, evaluation, experimental, fish, ITS, juvenile salmonid, juvenile salmonid passage, program, research, retrofit, salmonids, transportation, Washington, Washington state, wildlife, WSDOT


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/614.1.pdf http://wsdot.wa.gov/Research/Reports/600/614.1.htm
McCormack,E. D. WA-RD 607.1 Options for Benchmarking Performance Improvements Achieved from Construction of Freight Mobility Projects 2005 TRAC/UW
Abstract:
This report documents the development of data collection methodologies that can be used to cost effectively measure truck movements along specific roadway corridors selected by transportation agencies in Washington State. The intent of this study was to design and test methodologies that could be used to measure the performance of freight mobility roadway improvement projects against benchmarks, or selected standards, that would be used both as part of the project selection process and to report on speed and volume improvements that resulted from completed freight mobility projects. One technology tested was Commercial Vehicle Information System and Networks (CVISN) electronic truck transponders, which are mounted on the windshields of approximately 20,000 trucks in Washington. By using software to link the transponder reads from sites anywhere in the state, the transponder-equipped trucks could become a travel-time probe fleet. The second technology tested involved global positioning systems (GPS) placed in volunteer trucks to collect specific truck movement data at 5-second intervals. With GPS data it was possible to understand when and where the monitored trucks experienced congestion and to generate useful performance statistics. The study found that both data collection technologies could be useful; however, the key to both technologies is whether enough instrumented vehicles pass over the roadways for which data are required. This basic condition affects whether the technologies will be effective at collecting the data required for any given benchmark project. The report also recommends the traffic data that should be collected for a benchmark program and the potential costs of using either data collection technology.

Authors:
McCormack,E. D., Hallenbeck,M. E.

Keywords:
agencies, commercial vehicle, condition, congestion, construction, corridors, cost, costs, data, data collection, design, development, freight, freight mobility, freight movement reliability, global positioning, global positioning systems, GPS, improvement, methodology, mobility, networks, performance, positioning, probe program, project, research, roadway, software, speed, statistics, Study, System, systems, technology, traffic, traffic data, transportation, travel time, truck, truck monitoring, trucks, volume, Washington, Washington state


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/607.1.pdf http://wsdot.wa.gov/Research/Reports/600/607.1.htm
Kopf,J. WA-RD 619.1 Measurement of Recurring and Non-Recurring Congestion: Phase 2 2005 TRAC/UW
Abstract:
In 2003, the Washington State Department of Transportation (WSDOT) initiated a research effort to develop and test a methodology for estimating congestion delay on Seattle area freeways. The initial phase of the research developed a preliminary methodology for both measuring congestion and assigning that congestion to specific lane blocking incidents. In Phase 2 of this study, that methodology was automated and extended to include an examination of the effects of incidents occurring on the shoulders of the freeway, spillback from incident-caused congestion on one freeway that affects a second freeway that feeds traffic onto the initially congested facility, special events, and weather. Because funding for this effort was extremely limited, only three corridors (with both directions analyzed independently) and two months of data were analyzed. The project found that the Phase 1 methodology works well in assigning traffic congestion that occurs in the immediate time frame and geographic location of incidents to those incidents. It also showed that this process can be automated, making the data preparation effort now the primary determinant of the cost of additional work of this kind. Unfortunately, even with the addition of shoulder incidents, special events, and weather to lane blocking events, the automated process is unable to assign a significant proportion of the non-recurring delay occurring on Seattle freeways. The detailed analysis of freeway performance showed that much of the delay caused by specific incidents occurs in places or at times removed from the incident itself. The result is that much of the observed non-recurring delay can not be assigned to specific causes by the current analytical process. New analytical procedures will need to be developed in Phase 3 of this work. The Phase 2 analysis also confirmed that the congestion effects of specific incidents and other traffic disruptions are highly dependent on the background traffic conditions at the time of the disruption. While the Phase 2 analysis did not produce all of the results desired, the additional analyses showed that the summary statistics output from the Phase 2 software are useful as input to other analytical procedures.

Authors:
Kopf,J., Nee,J., Ishimaru,J. M., Hallenbeck,M. E.

Keywords:
congestion causes, freeway performance, traffic congestion, Washington, Washington state, transportation, WSDOT, research, methodology, congestion, seattle, freeway, developed, incident, Study, effects, traffic, facilities, corridors, data, project, cost, analysis, performance, in-place, condition, statistics, software


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/619.1.pdf http://wsdot.wa.gov/Research/Reports/600/619.1.htm
Hill,K. WA-RD 621.1 Roadside Vegetation Management Study: Literature Review, Interview Summaries, and Decision Framework 2005 TRAC/UW
Abstract:
This study was conducted for the Washington State Department of Transportation (WSDOT) to explore both the need for and the variety of alternatives to the use of an annual application of herbicides for removing vegetation in the area immediately adjacent to the pavement edge. Our study approached these questions in two different ways, developing both a literature review and a set of interviews with people who have specific knowledge or views of these issues. We conducted interviews with three groups of people to identify issues, maintenance alternatives, and significant literature references: (1) staff at other federal, state, and county transportation agencies, (2) staff and volunteers who work with advocacy groups, and (3) researchers at academic institutions who specialize in related areas. Our literature review contains a set of citations that present related management issues and alternative practices. The abstracts for these references were included when available. To summarize what we learned from the interviews and literature sources, we developed a decision framework that could be used to guide WSDOT district maintenance staff in formulating management plans for vegetation. The decision framework differs from current practice primarily in that it begins with the assumption that maintenance of the area immediately adjacent to the pavement is not necessary unless some particular, observable condition triggers the need for such maintenance.

Authors:
Hill,K., Horner,R. R.

Keywords:
agencies, Alternative, Annual, best practices, condition, counties, developed, environmental management, framework, group, herbicides, integrated vegetation management (IVM), interviews, Issues, maintenance, management, pavement, pavement edge, research, review, road ecology, roadside, roadside maintenance, roadside vegetation, Study, transportation, vegetation management, Washington, Washington state, weeds, WSDOT, Zone 1


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/621.1.pdf http://wsdot.wa.gov/Research/Reports/600/621.1.htm
Hieber,D. G. WA-RD 611.1 Precast Concrete Pier Systems for Rapid Construction of Bridges in Seismic Regions 2005 TRAC/UW
Abstract:
Increasing traffic volumes and a deteriorating transportation infrastructure have stimulated the development of new systems and methods to accelerate the construction of highway bridges. Precast concrete bridge components offer a potential alternative to conventional reinforced, cast-in-place concrete components. The use of precast components has the potential to minimize traffic disruptions, improve work zone safety, reduce environmental impacts, improve constructability, increase quality, and lower life-cycle costs. This study compared two precast concrete bridge pier systems for rapid construction of bridges in seismic regions. One was a reinforced concrete system, in which mild steel deformed bars connect the precast concrete components and provide the flexural strength of the columns. The other was a hybrid system, which uses a combination of unbonded post-tensioning and mild steel deformed bars to make the connections. A parametric study of the two types of systems was conducted using nonlinear finite element models to investigate the global response and likelihood of damage for various frame configurations. On the basis of this study, a practical method was developed to estimate maximum seismic displacements from the cracked section properties of the columns, the elastic design displacement response spectrum, and the base-shear strength ratio. The results of the global nonlinear finite element analyses suggest that the systems have the potential for good seismic performance. Further analytical and experimental research is needed to investigate the constructability and seismic performance of the connection details.

Authors:
Hieber,D. G., Wacker,J. M., Eberhard,M. O., Stanton,J. F.

Keywords:
Alternative, bridge, bridges, columns, concrete, concrete bridge, connections, constructability, construction, cost, costs, damage, design, developed, development, environmental, environmental impact experimental, finite element, highway, impact, impacts, infrastructure, methods, models, performance piers, precast, precast concrete, prestressed concete, quality, Rapid construction, Regions, reinforce concrete, research, response spectra, response spectrum, safety, seismic, seismic performance, steel strength, Study, substructures, System, systems, traffic, traffic volumes, trasportation, volume


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/611.1.pdf http://wsdot.wa.gov/Research/Reports/600/611.1.htm
Dailey,D. J. WA-RD 603.1 TrafficTV 2005 TRAC/UW
Abstract:
TrafficTV is a traffic and traveler information resource available on cable television (UWTV2 Channel 76). It began operation June 1, 1998, as part of the SmartTrek Operational Deployment under the name Traffic Channel. The SmartTrek evaluation of May 2001 identified several problems with Traffic Channel and recommended some improvements. This project made those changes and renamed the application TrafficTV. A series of meetings was held in June 2003. These meetings involved personnel from the Washington State Department of Transportation (WSDOT) Northwest Region, WSDOT Advanced Technology Branch, WSDOT Olympia office, the University of Washington's UWTV, and the UW Intelligent Transportation Systems Research Program. From these meetings came a set of recommended changes. These changes were made to TrafficTV and are documented in this report. Battelle Institute conducted a focus group in May 2004 to evaluate the resulting program. This focus group concluded that TrafficTV is a useful traveler information tool but has not had sufficient public exposure to make it widely known to the traveling public. A market penetration audit conducted by Media Audit in June and July 2004 indicated that when viewers were asked about TrafficTV, over 94,000 had seen the program within the last week. This was deemed surprisingly high, given the lack of external exposure and that viewers would have found TrafficTV only by word of mouth or by "channel surfing." Again, a conclusion of the audit was that additional exposure would make TrafficTV more valuable as a traveler information tool. As a result of the publicity recommendations, a banner has been added to the North West Region's traveler information page to alert users to the availability of TrafficTV.

Authors:
Dailey,D. J., Bradbury,J.

Keywords:
traveler information, cable TV, Intelligent transportation system, congestion information, traffic, evaluation, Washington, Washington state, transportation, WSDOT, intelligent transportation systems, systems, research, program, group, public


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/603.1.pdf http://wsdot.wa.gov/Research/Reports/600/603.1.htm
Al-Yagout,M. A. WA-RD 600.1 Improving Traffic Characterization to Enhance Pavement Design and Performance: Load Spectra Development 2005 TRAC/UW
Abstract:
This research addresses the understanding of, and need for, load spectra in future pavement design procedures and as a stepping stone toward more complete pavement design. The primary objective of this project was to develop truck axle load spectra for Washington State. To do this, axle load data collected at WIM stations throughout Washington State were used. The developed load spectra encompass the principal truck axles on the roadway network: single, tandem, and tridem. Achieving this objective allows the Washington State Department of Transportation, or any state highway agency with analogous traffic patterns, to accommodate the requirements of the 2002 Design Guide, developed through NCHRP Project 1-37A. A secondary objective of this project was to determine whether ESALs obtained from the developed load spectra are significantly different from historical values. Because the developed load spectra are transformable to ESALs, state highway agencies that decide not to use the new guide can still choose to employ the ESALs produced with the load spectra. The project concluded that the developed load spectra are reasonable. For single axles they are comparable to the 2002 Design Guide and MnROAD defaults. For tandem and tridem axles, they are slightly more conservative than defaults of the 2002 Design Guide and MnROAD, but they are still within reason. In addition, the ESALs per vehicle class associated with the developed load spectra are comparable to Washington State historical ESALs for vehicle classes 9, 10, and 13. The use of the newly developed ESALs per vehicle will generally increase design ESALs, but that increase will be due to inclusion of the less predominant vehicle classes (4, 6, 7, 8, and 11).

Authors:
Al-Yagout,M. A., Mahoney,J. P., Pierce,L., Hallenbeck,M. E.

Keywords:
agencies, axle, data, design, developed, development, equivalent single axel load, ESAL, highway, load spectra, pavement, pavement design, performance, project, research, roadway, single axle, traffic, transportation, truck, Washington, Washington state, weigh-in-motion, WIM


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/600.1.pdf http://wsdot.wa.gov/Research/Reports/600/600.1.htm
Turkiyyah,G. M. WA-RD 586.1 Feasibility of Backcalculation Procedures Based on Dynamic FWD Response Data 2004 TRAC/UW
Abstract:
The Falling weight deflectometer test (FWD) is a commonly used method for the evaluation of the structural performance of pavement systems. In the FWD test, a large weight is raised off the ground and dropped onto a rubber loading pad creating an impulse load representative of the real loading imposed by heavy traffic on the pavement. The excitation produced by the loading sets off waves in the pavement and underlying soil. Deflection time histories are gathered by an array of sensors placed at several nearby locations. The traditional method for interpreting the FWD data to backcalculate structural pavement properties, involves extracting the peak deflection from each displacement trace of the sensors (deflection basin) and matching it through an iterative optimization method to the deflections predicted by a static model of the pavement. This approach is computationally efficient; and when the depths of the layers are known, and their properties are largely homogeneous with depth, the procedure is effective in backcalculating layer properties. However, when the depths are uncertain or when the moduli vary within a layer, the static backcalculation scheme may not yield reliable results.The goal of this study is to investigate the feasibility and effectiveness of using the complete time history of the FWD test to overcome some of the limitations of the static backcalculation procedure, and recover pavement layer moduli distribution and thickness. The problem is also formulated as a numerical minimization problem, where the unknowns are the resilient moduli of thin "computational layers" that discretize the profile. Our initial finding is that this optimization formulation regularized by constraints on the magnitude and spatial gradient of the moduli, coupled with a continuation scheme for imposing the regularization terms, can overcome the ill-posedness nature or the original optimization problem. The computational effort for solving this inverse problem, however, is very significant as it requires repeated calls to the expensive forward problem: an elastodynamic simulation in stiff heterogeneous media. Additional work is needed to speed up the forward problem to be able to perform a more comprehensive evaluation with field data.

Authors:
Turkiyyah,G. M.

Keywords:
research, falling weight deflectometer, weight, evaluation, performance, pavement, systems, traffic, data, moduli, profile, speed


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/586.1.pdf http://wsdot.wa.gov/Research/Reports/500/586.1.htm
Papanicolaou,A. N. T. WA-RD 581.1 Investigation of Flow and Local Scour Characteristics Around a Partially Submerged Permeable WSDOT Barb 2004 TRAC/WSU
Abstract:
Barbs are wide crested trapezoidal structures, typically constructed of riprap gravel, which project out from the streambank and are oriented upstream into the main flow. Barbs reduce erosion along streambanks by deflecting current into the center of the channel aiding in the protection of bridge piers and abutments. The overall objective of this study is to establish design criteria for permeable barbs within non-navigable mild sloped gravel bed streams. The report consists of two major parts. Part one focuses on the flow characteristics around a submerged permeable barb to understand the flow regimes "formed" within the vicinity of a barb. Part two utilizes the quantitative data that are gathered in part one and investigates the complex evolution of local scour around the permeable barb under clear-water scour conditions.

Authors:
Papanicolaou,A. N. T., Kjos,L. J., Fox,J. F.

Keywords:
permeable and impermeable barbs, Scaling, time-averaged flow and turbulent parameters, backwater analysis, scour depth, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/581.1.pdf http://wsdot.wa.gov/Research/Reports/500/581.1.htm
Nee,J. WA-RD 584.1 HOV Lane Performance Monitoring 2002 Report: Volume 2--Trends 2004 TRAC/UW
Abstract:
High occupancy vehicle (HOV) lanes, also known as carpool lanes and diamond lanes, are designated for use by carpoolers, transit riders, ride sharers and motorcyclists that meet the occupancy requirement. By restricting access, the HOV lanes benefit users by allowing them to travel the freeway system at a faster speed, thus saving time, and experiencing greater time reliability in comparison to motorists on general purpose (GP) lanes. To accurately evaluate the system's effectiveness, a state policy requires an annual HOV system report to document system performance, examining the HOV lanes' person-carrying capability, travel time savings, and trip reliability benefits in comparison to adjacent GP lanes. HOV lane violation rates are also evaluated.This report describes the results of an extensive monitoring effort of HOV lane use and performance in the Puget Sound area in 2002. It presents an analysis of data collected to describe the number of people and vehicles that use HOV lanes, the reliability of the HOV lanes, the travel time savings in comparison to GP lanes, violation rates and public perceptions. This information is intended to serve as reliable input for transportation decision makers and planners in evaluating the impact and adequacy of the existing HOV lane system in the Puget sound area, and in planning for other HOV facilities.This is volume 1 of a two-volume set. Volume 2 provides an overview of major trends in HOV lane performance by comparing data presented in the 2000 HOV Performance Report.

Authors:
Nee,J., Ishimaru,J. M., Hallenbeck,M. E.

Keywords:
HOV lanes, HOV performance, high occupancy, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/584.1.pdf http://wsdot.wa.gov/Research/Reports/500/584.1.htm
Nee,J. WA-RD 584.2 HOV Lane Performance Monitoring 2002 Report -- Vol. 1 2004 TRAC/UW
Abstract:
High occupancy vehicle (HOV) lanes, also known as carpool lanes and diamond lanes, are designated for use by carpoolers, transit riders, ride sharers and motorcyclists that meet the occupancy requirement. By restricting access, the HOV lanes benefit users by allowing them to travel the freeway system at a faster speed, thus saving time, and experiencing greater time reliability in comparison to motorists on general purpose (GP) lanes. To accurately evaluate the system's effectiveness, a state policy requires an annual HOV system report to document system performance, examining the HOV lanes' person-carrying capability, travel time savings, and trip reliability benefits in comparison to adjacent GP lanes. HOV lane violation rates are also evaluated. This report describes the results of an extensive monitoring effort of HOV lane use and performance in the Puget Sound area in 2002. It presents an analysis of data collected to describe the number of people and vehicles that use HOV lanes, the reliability of the HOV lanes, the travel time savings in comparison to GP lanes, violation rates and public perceptions. This information is intended to serve as reliable input for transportation decision makers and planners in evaluating the impact and adequacy of the existing HOV lane system in the Puget sound area, and in planning for other HOV facilities. This is volume 1 of a two-volume set. Volume 2 provides an overview of major trends in HOV lane performance by comparing data presented in the 2000 HOV Performance Report.

Authors:
Nee,J., Ishimaru,J. M., Hallenbeck,M. E.

Keywords:
analysis, benefit, benefits, carpool, data, facilities, freeway, GP lanes, high occupancy, high occupancy vehicle, HOV, HOV facilities, HOV lanes, HOV performance, monitoring, occupancy, performance, performance monitoring, planning, policy, public, reliability, research, speed, transit, transportation, travel time, violation, volume


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/584.2.pdf http://wsdot.wa.gov/Research/Reports/500/584.2.htm
Li,J. WA-RD 588.1 Application of HDM-4 in the WSDOT Highway System 2004 TRAC/UW
Abstract:
This project performed extensive study and systematic research on the application of the Highway Development and Management system (HDM-4) to the Washington State Department of Transportation (WSDOT) highway system. Data processing, testing, calibration, and analysis were executed to provide the WSDOT with a new budget planning tool. HDM-4 flexible pavement deterioration models were calibrated with the assistance of the Washington State Pavement Management System. A method to calibrate concrete pavement distress models is proposed. This research also explored the application of HDM-4 analysis at the project, program, and strategic levels. The applications include prediction of pavement conditions during a defined analysis period, calculation of required budgets for optimal pavement conditions and maximum economic indicators, establishment of optimized work programs under varying levels of constrained budgets, and other applications for WSDOT.

Authors:
Li,J., Muench,S. T., Mahoney,J. P., Pierce,L., Sivaneswaran,N.

Keywords:
HDM-4, models, pavement maintenance, pavement management, pavement performance, Pavement preservation, vehicle operating costs, research, highway, development, management, management system, Washington, Washington state, transportation, WSDOT, data, calibration, analysis, planning, pavement, deterioration, concrete, program, applications, prediction, condition, indicators


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/588.1.pdf http://wsdot.wa.gov/Research/Reports/500/588.1.htm
Kristof,T. WA-RD 597.1 Assessing the Benefits of Traveler and Transportation Information Systems 2004 TRAC/UW
Abstract:
The goal of advanced traveler information systems (ATIS) is to provide travelers with information that will facilitate their decisions concerning route choice, departure time, trip delay or elimination, and mode of transportation. The benefits of ATIS projects can be evaluated through field studies, simulation software, and surveys. An evaluation method called the ITS Deployment Analysis System (IDAS) is suggested for use by the Washington State Department of Transportation (WSDOT). IDAS is a "sketch" planning tool intended for screening and prioritizing all intelligent transportation systems (ITS) projects (not just ATIS projects). The software evaluates a number of benefits. These are determined by changes attributable to the deployment of ITS in vehicle miles traveled (VMT), vehicle hours traveled (VHT), volume-capacity (v/c) ratios, and vehicle speeds throughout a given network. The IDAS evaluation depends on a number of assumptions that affect the calculations of costs and benefits. The IDAS developers recommend that these assumptions be inspected by local agencies and adjusted to better represent local conditions. The assumptions about the impacts on VMT, VHT, v/c ratios, and vehicle speed are particularly important. Consequently, suggestions are made within this report for adjustments that WSDOT should make to these default values. These values will allow the WSDOT to successfully employ IDAS for ATIS evaluation.

Authors:
Kristof,T., Lowry,M., Rutherford,G. S.

Keywords:
advanced traveler information systems, agencies, analysis, Assessing, ATIS, ATIS benefits, ATIS evaluation, benefit, benefits, condition, cost, costs, Deployment, evaluation, IDAS, impact, impacts, information systems, Intelligent transportation system, intelligent transportation systems, ITS, ITS Deployment Analysis System, planning, prioritizing, project, research, software, speed, Study, survey, Surveys, System, systems, transportation, traveler information, Washington, Washington state, WSDOT


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/597.1.pdf http://wsdot.wa.gov/Research/Reports/500/597.1.htm
Igharo,P. O. WA-RD 580.1 In-Service Performance of Guardrail Terminals in Washington State 2004 St. Martin's College/WSDOT
Abstract:
This research study was conducted to evaluate the in-service performance of existing guardrail end treatments and unrestrained pre-cast concrete barrier in Washington State. For a selected area of the state highway system over a one-year period, local area maintenance personnel were tasked to document incidents, including extent of damage and repair costs, into a database using NCHRP Project 22-13 methodology. Additional information (accident severity, e.g.) from police reports was gathered from the incidents and added to the database. The installation characteristics measured for Breakaway Cable Terminals (BCT) and Slotted Rail Terminals (SRT), along with the related crash data for these devices, showed overall acceptable performance when struck. Review of the incident severities, together with the displacement and damage data on struck barriers in the study area, revealed no significant difference in BCT and SRT performance. The installation, damage, and displacement characteristics examined on struck concrete barrier showed that the pin and loop connections were holding well in incidents, and the barrier displacements during incidents were within the WSDOT design specification for such systems.

Authors:
Igharo,P. O., Murphy,J., Glad,R. W.

Keywords:
performance, guardrail, Washington, Washington state, guardrail end treaments, breakaway cable terminal (BCT), roadside safety, slotted rail terminal (SRT), research, end treatment, precast concrete, concrete, concrete barrier, highway, maintenance, incident, damage, repair, costs, cost, database, methodology, accident severity, data, barriers, WSDOT, design, specification, systems


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/580.1.pdf http://wsdot.wa.gov/Research/Reports/500/580.1.htm
Hallenbeck,P. WA-RD 583.1 Evaluation of Oil Rebate Expenditures Undertaken in Association with the Freeway and Arterial Management Effort (FAME) 2004 TRAC/UW
Abstract:
Oil Rebate funds have allowed FAME to spearhead technological breakthroughs in communication that both decrease the duration of congestion, and allow travelers to avoid the congestion as it occurs, thus decreasing energy used for travel, and pollutants generated by travel. Oil rebate funds have allowed FAME to perform a number of groundbreaking studies that have improved the state's ability to control and manage traffic. Further, the $1.4 million in Oil Rebate funding for FAME has been used to leverage over $4.6 milion from other funding sources.The majority of the 23 projects that have been partially or wholly funded by Oil Rebate monies have been very successful; meanwhile, projects with unsatisfactory outcomes were frequently terminated before completion, and rebate monies were re-allocated to other, more promising opportunities. The use of Oil Rebate funding has decreased the risks associated with investigating non-traditional approaches to traffic flow improvements, and allowed WSDOT to begin quantifying benefits that could be gained from new approaches to dealing with congestion problems.

Authors:
Hallenbeck,P.

Keywords:
energy savings, Oil Rebate, pollution reduction, research


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Collins,B. M. WA-RD 595.1 The Long-Term Performance of Geotextile Separators, Bucoda Test Site--Phase III 2004 TRAC/UW
Abstract:
This research was Phase III of field investigations carried out over 12 years at a test section in southwest Washington State in an effort to quantify the contribution of geotextile separators to the long-term performance of pavement sections. Five different geotextile separators, as well as a control (soil-only) section, were installed in a test section covering two lanes with different base course thicknesses on a low volume but heavily loaded rural highway west of Bucoda, Wash. Phase I evaluated the performance of the separators during construction. Phases II and III were conducted to evaluate the performance of the separators 5 and 12 years after construction, respectively. Field and laboratory tests were conducted on the subgrade, granular base materials, and the geotextiles as part of the effort to correlate the performance of the pavement section to the presence of the geotextile separators. Falling weight deflectometer (FWD) testing was also performed at the site as part of the effort to quantify the performance of the pavement section. The laboratory tests indicated that the geotextiles successfully performed their separation function over the 12-year period. However, the soil-only sections had a minimal amount of intermixing at the base course/subgrade interface, indicating that the separation benefits of geotextiles may not be realized under relatively thick pavement sections. Field density tests indicated that the density of the subgrade in the sections with a geotextile generally increased between construction and the first field investigation, whereas the density of the soil-only sections remained about the same. Similarly, the FWD tests showed that the most significant increase in the subgrade moduli occurred in the first few months following construction. However, the soil-only sections exhibited behavior similar to the sections with geotextiles during the FWD testing, suggesting that for the relatively thick pavement sections, incorporation of geotextiles may not have provided a significant contribution to the overall performance of the section over the 12-year period. Some of the FWD results did suggest that geotextiles might contribute to an increase in the base course modulus over time.

Authors:
Collins,B. M., Holtz,R. D.

Keywords:
base, behavior, benefit, benefits, construction, control, density, falling weight deflectometer, field investigations, geotextile, geotextile separators, highway, materials, moduli, pavement, pavement performance, pavement section, research, rural, separators, subgrade, tests, volume, Washington, Washington state, weight, performance


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/595.1.pdf http://wsdot.wa.gov/Research/Reports/500/595.1.htm
Chalker-Scott,L. WA-RD 582.1 Determination of the Effects of Anit-Icer Compounds upon the Rare Plant Hackelia Venusta 2004 TRAC/UW
Abstract:
The objective of the study was to determine whether Washington State Department of Transportation's winter use of road anti-icer compounds on Highway 2 in Chelan County, Washington, is having an impact on the federally endangered plant species Hackelia venusta. A contolled study was performed in the outdoor facilities at the Center for Urban Horticulture-University of Washington. This study evaluated two road anti-icer formulae available to WSDOT in the 2000-2002 winter seasons by testing the effects of different anti-icer dilutions on plant and soil parameters. Since it was not feasible to use H. venusta in a controlled study during the time of implementation, two other species were used. One species, Mertensia platphylla, is a phylogenetic relative and the other, Eriophyllym lanatum, is a non-related ecosystem associate. From the analysis, we were able to conlude that both road anti-icers begin to have detrimental effects by causing a decrease in aboveground biomass and survival on the two plant species examined when the concentrations reached 1part anti-icer: 100 parts solution. Given the information obtained from our study's results, more work is needed in order to better understand the implications of these results on the effects road anti-icerformulae have on H. venusta.

Authors:
Chalker-Scott,L., Brickey,J.

Keywords:
deicer compounds, hackelia venusta, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/582.1.pdf http://wsdot.wa.gov/Research/Reports/500/582.1.htm
Carlson,T. J. WA-RD 590.1 Plan for Pile-driving Research 2004 Battelle Pacific Northwest Division of Battel
Abstract:
This document presents a plan pile driving research based on the issues and needs of the WSDOT and resource agencies and on discussions that took place during an April 2004 pile driving workshop that was sponsored by WSDOT and coordinated by Battelle. The work plan is designed to meet WSDOT/WSF needs for pile driving research and to further understanding of pile driving impacts to aquatic animals in the Puget Sound.

Authors:
Carlson,T. J., Sargeant,S. L., Johnson,G. E.

Keywords:
acoustics, barotrauma, behavior, fish, hearing, pile-driving, research, WSDOT, impacts


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/590.1.pdf http://wsdot.wa.gov/Research/Reports/500/590.1.htm
Yonge,D. R. WA-RD 559.1 An Evaluation of Stormwater Permeable Rapid Infiltration Barriers for Use in Class V Stormwater Injection Wells 2003 TRAC/WSU
Abstract:
Stormwater injection wells are widely used as stormwater management systems. These wells may act as a low resistance conduit for contaminants transported by stormwater to enter groundwater. This paper summarizes the testing of a natural filtration medium, referred to as a Stormwater Permeable Rapid Infiltration Barrier (SPRIB), that has been proposed as a potential retrofit option for stormwater injection wells in Spokane, Washington, because of its theoretical contaminant attenuation capabilities and its good hydraulic properties. This medium was tested in the laboratory and at a field site using near field-scale columns to determine its useful life span in terms of metal (Cu, Pb, and Zn) removal capacity and maintenance of acceptable infiltration rates. After a series of simulated storm events, the SPRIB demonstrated contaminant concentration reduction rates of total metals greater than 99% and soluble metals from 91% to 98%. Surface clogging of the columns by stormwater particulate matter was shown to be the limiting factor in the useful life span of an unmaintained SPRIB. Based on the observed linear decline in infiltration rates due to sediment loading, the predicted life span of SPRIB is 20 to 22 storms (roughly 6 months in the Spokane area) before infiltration falls below acceptable rates (8 to 12 in/hr). A significantly longer life span is expected if pretreatment for suspended solids or periodic SPRIB maintenance is performed.

Authors:
Yonge,D. R., Roelen,P.

Keywords:
highway runoff, stormwater treatment, dry well, retrofit, research


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http://www.wsdot.wa.gov/research/reports/fullreports/559.1.pdf http://wsdot.wa.gov/Research/Reports/500/559.1.htm
Wall,Z. WA-RD 577.1 Automata Model for Congestion Prediction 2003 TRAC/UW
Abstract:
The overall goal of this project is to create a method for predicting traffic congestion on freeway corridors. When implemented, it will provide a traffic service like that of "pin-point Doppler" weather radar that can predict growing or dissipating congestion. Preliminary versions of the model used real-time loop data to successfully reproduce traffic behavior under moderately congested conditions. To improve the model for heavily congested conditions, the model had to be accurately calibrated. The process of calibrating the model revealed that inductance loop errors were preventing accurate results. An algorithm to correct the data from improperly functioning loops was developed and published at the 2003 Transportation Research Board Annual Meeting. The corrected loop data from the TDAD (Traffic Data Acquisition and Distribution) data mine are now being used to calibrate the model. The algorithm created in support of this effort can be used with malfunctioning loops to improve the freeway management system performance monitoring effort.

Authors:
Wall,Z., Dailey,D. J.

Keywords:
General automata, loop data, real-time data, traffic management, congestion prediction, recurring congestion, non-recurring congestion, car following, research


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http://www.wsdot.wa.gov/research/reports/fullreports/577.1.pdf http://wsdot.wa.gov/Research/Reports/500/577.1.htm
Uhlmeyer,J. S. WA-RD 571.1 NovaChip 2003 Materials Laboratory//WSDOT
Abstract:
NovaChip is marketed as a pavement rehabilitation, preventive maintenance, or surface treatment that has an extremely durable surface with improved skid resistance and resistance to rutting and wear. As a thin (3/8 to 3/4 inch), gap-graded hot-mix asphalt, NovaChip is recommended for structurally sound pavements and has the possibility of being a viable alternative to a bituminous surface treatment (BST) or a thin dense-graded overlay. For the Washington State Department of Transportation (WSDOT), the first NovaChip application in Washington State was selected as a replacement to a BST or SB17 through the City of Soap Lake. This report summarizes the design and construction experiences learned on this project, performance to date, and includes discussion of costs and future use recommendations in Washington.

Authors:
Uhlmeyer,J. S., Pierce,L. M., Weston,J. T.

Keywords:
NovaChip, asphalt, thin overlay, research


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http://www.wsdot.wa.gov/research/reports/fullreports/571.1.pdf http://wsdot.wa.gov/Research/Reports/500/571.1.htm
Symans,M. D. WA-RD 553.1 Evaluation of Displacement-Based Methods and Computer Software for Seismic Analysis of Highway Bridges 2003 TRAC/WSU
Abstract:
The response of bridges when subjected to seismic excitation can be evaluated by a number of analysis methods. The traditional approach to seismic analysis focuses on forces (so-called force-based methods of analysis) while current design practice is moving towards an increased emphasis on displacements (so-called displacement-based methods of analysis). The primary objective of this research project was to evaluate the effectiveness of various commerically-available computer programs for performing practical displacement-based seismic analysis of highway bridges. A secondary objective was to identify the fundamental differences between force-based and displacement-based methods of analysis, particularly as they apply to highway bridges. The objectives of the project were met by utilizing four different computer programs to evaluate the seismic response of a simple two-span highway bridge. The seismic response was evaluated using two force-based methods of analysis (response spectrum and time-history) and two displacement-based methods (capacity spectrum and inelastic demand spectrum). Furthermore, the effects of two differnent abutment and bent foundation support conditions were evaluated. The experience gained by utilizing the computer software revealed that some programs were well suited to displacement-based analysis, both from the point-of-view of being efficient and providing insight into the behavior of plastic hinges. The results of the seismic analyses demonstrated that force-based methods of analysis may be conveniently used to prioritize cases under which displacement-based methods of analysis should be applied. Furthermore, the displacement-based methods of analysis that were used produced different predictions of nonlinear response with neither method being regarded as producing accurate results due to a number of simplifications inherent in the methods. Finally, the displacement-based methods of analysis appear to be attractive to practicing engineers in the sense that they emphasize a graphical evaluation of seismic performance.

Authors:
Symans,M. D., Shattarat,N. K., McLean,D. I., Cofer,W. F.

Keywords:
displacement-based seismic analysis, force-based seismic analysis, pushover analysis, nonlinear static analysis, capacity spectrum analysis, bridge design, earthquake, research


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http://www.wsdot.wa.gov/research/reports/fullreports/553.1.pdf http://wsdot.wa.gov/Research/Reports/500/553.1.htm
Schoepflin,T. N. WA-RD 575.1 Algorithms for Estimating Mean Vehicle Speed Using Uncalibrated Traffic Management Cameras 2003 TRAC/UW
Abstract:
This report documents the second project, in a series of three research projects funded by the Washington State Department of Transportation (WSDOT), that will enable already deployed, uncalibrated CCTV cameras to be used as traffic speed sensors. The principle traffic speed sensors currently deployed by WSDOT are inductance loops; however, in some locations, it is impractical or too expensive to install loops. In addition, a large number of un-calibrated cameras are already in place and being used by the traffic management operators to qualitatively assess traffic both on the freeway and on arterials. These projects will leverage the existing cameras to provide a quantitative measurement of traffic speed similar to that which can be obtained using loops in the roadway. The implementation of this research will culminate with software that creates an automated system compatible with the existing TMS. This system will leverage the existing camera investment to create a new set of speed sensors that increases the geographic extent of the TMS's quantitative surveillance capabilities.In the second phase, reported on here, roadway features are used to augment the camera calibration. This overcomes the occlusion problem, or apparent blending together of small vehicles as seen in the far field of the camera images, that existed in the first phase. Activity maps, fog lines,and vanishing points are a few of the additional features used, and the details of these algorithms are described in this report. These results havae also been peer reviewed and published.

Authors:
Schoepflin,T. N., Dailey,D. J.

Keywords:
CCTV cameras, video image processing, calibration, speed sensor, vehicle length distribution, kalman filter, research


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http://www.wsdot.wa.gov/research/reports/fullreports/575.1.pdf http://wsdot.wa.gov/Research/Reports/500/575.1.htm
Pearson,S. F. WA-RD 567.1 Breeding Phenology, Nesting Success, Habitat Selection, and Census Methods for the Streaked Horned Lark in the Puget Sou... 2003 Washington Dept. of Natural Resources
Abstract:
The Streaked Horned Lark is a recognized subspecies of the Horned Lark and is a federal and state candidate for listing under the state and federal Endangered Species Act. In the spring and summer of 2002, three field assistants and the author conducted research on this subspecies at four research sites in the south Puget Sound. The specific objectives of this research were five-fold: 1) describe Streaked Horned Lark breeding phenology and life history; 2) assess reproductive success in four of the populations where males have been reported singing and performing flight displays; 3) identify habitat features important to successful breeding at the nest site and territory scales; 4) assess the impacts of human activities on Streaked Horned Larks at the 13th Division Prairie; 5) develop a Streaked Horned Lark survey protocol that could be used by Washington Department of Transportation biologists to determine species presence or absence.

Authors:
Pearson,S. F.

Keywords:
breeding phenology, nesting success, habitat selection, census methods, streaked horned lark, research


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Nee,J. WA-RD 518.2 Evaluation of the Instant Tow Dispatch Pilot Program in the Tacoma Area - A Supplement to the Evaluation of the Service ... 2003 TRAC/UW
Abstract:
As part of a larger Service Patrol Pilot Demonstration effort, the Service Patrol Study Steering Committee proposed a separate element, the Instant Tow dispatch program (IT)--also known as an "expedited" rotational call-out tow truck program--to be evaluated for its potential to reduce incident response time. The goals of the IT test program were to decrease congestion and reduce potential safety risk on the highway by providing timely removal of blocking collisions or disabled vehicles.In the original test operations from January through April 2002, the IT disptach was not successfully implemented as designed because the protocol for the expedited dispatch process was not followed consistently. The project partners subsequently decided that additional effort should be made, and another round of data collection over a three-month period followed from September through November 2002. While efforts were made to ensure that the protocol for the expedited dispatch process was consistently followed, the use of expedited tows in the Tacoma study area was still limited in the coverage area during the hours of its operation. As a result of the limited number of data collected, no definitive conclusion about the program's effectiveness can be established. However, the available information seems to indicate that the IT protocol allows two vehicles to be notified more quickly than the standard rotational tow truck call-out protocol; hence, it would help decrease overall incident time and resulting traveler delay.This supplement summarizes the institutional and operation issues affecting the IT Dispatch pilot program, the evaluation results based on the operations from September through November 2002, and the evaluation's recommendations.

Authors:
Nee,J., Hallenbeck,M. E.

Keywords:
service patrols, incident response time, traffic delay, traffic safety, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/518.2.pdf http://wsdot.wa.gov/Research/Reports/500/518.2.htm
McLean,D. I. WA-RD 558.1 Experimental Response and Analysis of the Evergreen Point Floating Bridge 2003 TRAC/WSU
Abstract:
On January 20, 1993, the Evergreen Point Floating Bridge incurred structural damage at two mooring cables and at various other locations during a storm event of approximately a 20-year return period magnitude. The two mooring cables damaged were the shorter and stiffer cables located at the ends of the bridge. Following the l993 storm, larger mooring cables with Sealink elastomeric devices were installed at the areas where cable distress was noted to resist higher cable loads and to provide energy absorption and reduced cable stiffness. In this study, cable forces were measured during the winter season of 2001-2002 to evaluate the effectivensss of the replacement mooring cables. From the experimental measurements, it was found that the special replacement mooring cables have reduced the load attraction at the shorter end cables when compared to cable tension values reported for the pre-retofit analysis. However, the measurements indicate that the replacement cables continue to attract loads between 64% and 79% higher than those measured at the longer and more flexible cables located near the midspan of the floating bridge during storm events of a 1-year return period magnitude.

Authors:
McLean,D. I., Peterson,S. T.

Keywords:
floating bridge, wave loading, experimental response, Sealink elastomer, mooring cable, research


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http://www.wsdot.wa.gov/research/reports/fullreports/558.1.pdf http://wsdot.wa.gov/Research/Reports/500/558.1.htm
Mass,C. F. WA-RD 564.1 A Next-Generation Land Surface Model for the Prediction of Pavement Temperature 2003 TRAC/UW
Abstract:
To meet the information needs of highway maintenance managers, a system for real-time prediction of pavement temperatures was developed at the University of Washington. This system utilizes the NOAH land surface model (National Center for Environmental Prediction, Oregon State University, Air Force, Hydrologic Research Lab LSM) to estimate fluxes of energy to and from the pavement surface and resulting pavement surface temperatures. Data from real-time MM5 weather prediction model forecasts, performed twice-daily at the UW, were used as initial and boundary conditions in pavement temperature simulations. Results of these simulations were compared to observations and the system's forecast skill was verified.

Authors:
Mass,C. F.

Keywords:
pavement temperature, pavement surface, real-time prediction, weather prediction, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/564.1.pdf http://wsdot.wa.gov/Research/Reports/500/564.1.htm
Lehman,D. E. WA-RD 569.1 Cotton Duck Bearing Pads: Engineering Evaluation and Design Recommendations 2003 TRAC/UW
Abstract:
Cotton duck bearing pads (CDP) are sometimes used to support loads and accommodate movements and rotations at bridge bearings. CDP are preformed elastomeric pads consisting of thin layers of elastomer interlaid with fabric, and they are manufactured under Military Specifications with limited guidance from the AASHTO. The behavior of these CDP bearing pads was experimentally evaluated to establish design models for predicting this behavior, to determine the variation in behavior expected with different bearing pad manufacturers, and to develop design recommendations. This research is a follow-up study of an earlier research program sponsored by Arkansas State University.CDP bearing pads from three different manufacturers were tested, and the test program included dynamic and static (or monotonic) tests of bearings in shear, compression,and rotation. In general, the static tests were used to evaluate strength, stiffness, deformation limits, and general pad behavior. The dynamic tests examined durability and performance under repeated loading and deformation.The results of this test program were used to develop design recommendations, and an appendix includes a draft of proposed wording for modification of the AASHTO LRFD Specifications to include these design recommendations. In addition, a spreadsheet was developed in Microsoft EXCEL to accomplish the calculations necessary to complete the design.

Authors:
Lehman,D. E., Roeder,C. W., Larsen,R., Curtin,K.

Keywords:
cotton duck bearing pads, CDP, bridge bearings, bridge design, loads, bridge, specifications, specification, behavior, design, models, research, program, tests, strength, durability, performance


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http://www.wsdot.wa.gov/research/reports/fullreports/569.1.pdf http://wsdot.wa.gov/Research/Reports/500/569.1.htm
Hallenbeck,M. E. WA-RD 566.1 Freight Data from Intelligent Transportation System Devices 2003 TRAC/UW
Abstract:
As congestion increases, transportation agencies are seeking regional travel time data to determine exactly when, how, and where congestion affects freight mobility. Concurrently, a number of regional intelligent transportation systems (ITS) are incorporating various technologies to improve transportation system efficiency. This research explored the ability of these ITS devices to be used as tools for developing useful historical, and perhaps real-time, traffic flow information.Regional transponder systems have required the installation of a series of readers at weigh stations in ports, along freeways, and at the Washington/British Columbia border. By linking data from these readers, it was possible to anonymously track individual, transponder-equipped trucks and to develop corridor-level travel time information. However, the research found that it is important to have an adequate number of data points between readers to identify non-congestion related stops. Another portion of this research tested five GPS devices in trucks. The research found that the GPS data transmitted by cellular technology from these vehicles can provide much of the facility performance information desired by roadway agencies. However, obtaining sufficient amounts of these data in a cost effective manner will be difficult. A third source of ITS data that was explored was WSDOT's extensive loop-based freeway surveillance and control system.The output from of each of the ITS devices analyzed in this research presented differing pictures (versions) of freight flow performance for the same stretch of roadway. In addition, ITS data often covered different (and non-contiguous) roadway segments and systems or geographic areas. The result of this wide amount of variety was an integration task that was far more complex then initially expected.Overall, the study found that the integration of data from the entire range of ITS devices potentially offers both a more complete and more accurate overall description of freight and truck flows.

Authors:
Hallenbeck,M. E., McCormack,E. D., Nee,J., Wright,D.

Keywords:
freight data, ITS devices, data collection, data management, research


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http://www.wsdot.wa.gov/research/reports/fullreports/566.1.pdf http://wsdot.wa.gov/Research/Reports/500/566.1.htm
Dailey,D. J. WA-RD 579.1 AVL-Equipped Vehicles as Speed Probes (Phase 2) 2003 TRAC/UW
Abstract:
Performance monitoring is an issue of growing concern both nationally and in Washington State. Travel times and speeds have always been of interest to traveler-information researchers, but as they become a key measure in performance monitoring, this interest is now greater than ever. However, instrumenting the roadway infrastructure to obtain this type of data is very expensive. In this project, we use transit vehicles as probe sensors and develop a framework to use the vehicle position estimates as a speed sensor.This report documents the second phase of a three-phase project that will create a robust set of virtual sensors for freeways and arterials. The first phase was a proof of principle that examined the statistics of successfully using transit vehicles as traffic probes. The results of the second phase are presented in this report. An optimal filter method is described that estimates acceleration, speed, and position as a function of space and time. The third phase will implement a server to place speed estimates from the transit probe virtual sensors into the WSDOT Northwest Region's operational Traffic Management System. WSDOT will benefit from this work by gaining additional traffic management sensing capabilities without the additional installation and maintenance costs of cabinets, loops, and communications. The traveling public in metropolitan Seattle will benefit from having additional traveler information about arterials that can be used as alternatives to freeway travel. Publication of results that validate the techniques used to derive virtual sensors from transit probe vehicles will have a national impact as an increasing number of cities use transit fleet management systems.

Authors:
Dailey,D. J., Cathey,F. W.

Keywords:
bus, transit, probe, Claman filters, Kalman smoother, GIS, AVL, TCIP, MML, virtual sensors, traffic probes, transit probes, speed sensors, geographic information systems, road traffic, traffic control, traffic engineering computing, transportation, research


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http://www.wsdot.wa.gov/research/reports/fullreports/579.1.pdf http://wsdot.wa.gov/Research/Reports/500/579.1.htm
Dailey,D. J. WA-RD 565.1 ITS Backbone Infrastructure 2003 TRAC/UW
Abstract:
In this brief report, we provide a description of the activities in each of the areas to which the Backbone contributes, and we provide supporting statistics for each of these contributions. The form of these statistics varies by application area: (1) potential viewers, in the case of Traffic TV, (2) page views in the case of MyBus, (3) data stream use, in the case of Busview, and (4) number of downloads, in the case of the SDD Toolkit.

Authors:
Dailey,D. J.

Keywords:
intelligent transportation systems, backbone, real-time data, standard interface, research


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http://www.wsdot.wa.gov/research/reports/fullreports/565.1.pd http://wsdot.wa.gov/Research/Reports/500/565.1.htm
Chayanan,S. WA-RD 562.1 Interaction Between the Roadway and Roadside--An Econometric Analysis of Design and Environmental Factors Affecting Segm... 2003 TRAC/UW
Abstract:
The purpose of this research was to explore the relationship between roadway and roadside accidentrates for Washington State highways to improve the Washington State Department of Transportation's(WSDOT) process of modeling roadway and roadside accident rates and to arrive at possible improvements in the efficiency of WSDOT's safety project programming process.The project tested the use of the seemingly unrelated regression estimation (SURE) model to modelthe roadway and roadside simultaneously. The theoretical advantage of the SURE approach is that it does not impose any a priori assumptions on the explicit linkage between roadway and roadside accident rates, and there is no theoretical support for explicit linkage, either. The data used to derive this model were from a random sample of 500 one-mile sections from the Washington State highway system. Traffic dataincluded traffic volumes, truck compositions, AADT, traffic speeds, and other relevant information.Geometric data included lane, shoulder, median, curve, and intersection information. Historical weather data such as monthly precipitation and temperature were collected from the National Oceanic and Atmospheric Administration database.In comparing significant explanatory variables between the roadway accident rate and roadsideaccident rate models, very few variables were common. This confirms that it is preferable to specifyseparate functional forms for roadway and roadside accident rates. Empirical results indicated thatcorrelation between roadway and roadside accident rates was insignificant, indicating that efficiency gainsfrom the SURE model would be minimal. The important finding from a programming standpoint is thatjointly modeling the roadway and roadside simultaneously would not result in significant efficiencyimprovements in comparison to the current state-of-the-practice in Washington State.

Authors:
Chayanan,S., Nebergall,M., Shankar,V., Juvva,N., Ouyang,Y.

Keywords:
roadway, roadside, accident rates, safety programming, research, Washington, Washington state, highway, transportation, WSDOT, modeling, safety, regression, linkage, data, traffic, traffic data, volume, truck, speed, median, temperature, database, models


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http://www.wsdot.wa.gov/research/reports/fullreports/562.1.pdf http://wsdot.wa.gov/Research/Reports/500/562.1.htm
Avery,R. P. WA-RD 563.1 Central Puget Sound Freeway Network Usage and Performance, 2001 Update 2003 TRAC/UW
Abstract:
This summary report presents an overview of the level of traveler usage (e.g., how many vehicles use the freeways) and travel performance (e.g., how fast they are traveling, where and how often congestion ocurs) on the principal urban freeways in the central Puget Sound area. The freeways studied in this project are managed by the Washington State Department of Transportation (WSDOT) using its FLOW system, a coordinated network of traffic monitoring, measuring, information dissemination, and control devices that operates on urban state and Interstate highways in the central Puget Sound region. Data presented in this report were collected by the WSDOT's freeway surveillance system. The project that led to this report is intended to meet two separate purposes: 1) to enhance WSDOT's ability to monitor and improve its traffic management efforts on Seattle-area highways, and 2) to provide useful information to the public and decision makers about the status of the freeway system's operational performance. This report is primarily intended to meet the second of these objectives. However, the software developed to assist in freeway data analysis for this project and many of the graphics presented in this report are directly applicable to the first objective.

Authors:
Avery,R. P., Ishimaru,J. M., Nee,J., Hallenbeck,M. E.

Keywords:
analysis, Archived Data User Services (ADUS), congestion, congestion monitoring, control, data, flow, freeway, freeway performance, highway, information dissemination, ITS, management, monitoring, performance, public, research, surveillance, traffic, traffic management, traffic monitoring, transportation, urban, Washington, Washington state, WSDOT


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http://www.wsdot.wa.gov/research/reports/fullreports/563.1.pdf http://wsdot.wa.gov/Research/Reports/500/563.1.htm
Allen,T. M. WA-RD 522.2 Prediction of Reinforcement Loads in Reinforced Soil Walls 2003 TRAC/UW
Abstract:
Proper estimation of soil reinforcement loads and strains is key to accurate design of the internal stability of geosynthetic and steel reinfoced soil structures. Current design methodologies use limit equilibrium concepts to estimate reinforcement loads for internal stability design, with empirical modifications to match the prediction to observed reinforcement loads at working stresses. This approach has worked reasonably well for steel reinforced walls but appears to seriously overestimate loads for geosynthetic walls.A large database of full-scale geosynthetic walls (16 fully instrumented, full-scale geosynthetic walls and 14 walls with limited measurements), full-scale steel reinforced wall sections was utilized to develop a new design methodology based on working stress principles, termed the K-Stiffness Method. This new methodology considers the stiffness of the various wall components and their influence on reinforcement loads. Results of simple statistical analyses to evaluate the ratio of predicted to measured peak reinforcement loads in geosynthetic walls were telling: the AASHTO Simplified Method results to an average ratio of measured to predicted loads of 0.45 with a coefficient of variation (COV) of 91 percent, whereas the proposed method results in an average of 0.99 and a COV of 36 percent. The proposed method remains accurate up until the point at which the soil begins to fail (approximaely 3 to 5 percent strain). For steel reinforced MSE walls, the improvement was more modest: AASHTO's Simplified Method results in an average ratio of predicted to measured loads of 1.12 with a (COV) of 45 percent, whereas the new K-Stiffness Method results in an average of 0.95 and a COV of 32 percent. The objective of the method is to design the wall reinforcement so that the soil within the wall backfill will not reach a state of failure consistent with the notion of working stress conditions. This soil failure limit state is not considered in the design methods currently available, yet, given the research results presented herein, is likely to be a controlling limit state for geosynthetic structures.The fruit of this research is a more accurate method for estimating reinforcement loads, thereby reducing reinforcement needs and improving the economy of reinforced soil walls. The scope of this research was limited to reinforced soil walls that utilize granular (non-cohesive, relatively low silt content) backfill.

Authors:
Allen,T. M., Bathurst,R. J.

Keywords:
reinforcement, walls, loads, strains, creep, design, research


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http://www.wsdot.wa.gov/research/reports/fullreports/522.2.pdf http://wsdot.wa.gov/Research/Reports/500/522.2.htm
Young,R. WA-RD 547.1 Multimodal Investment Choice Analysis - Vol. I: Phase I 2002 TRAC/UW
Abstract:
The Multimodal Investment Choice Analysis (MICA) project is developing a computer-based tool to assist the Washington State Department of Transportation (WSDOT), the Washington State Transportation Commission, and the Washington State Legislature in making state transportation funding decisions. The function of MICA is to summarize the multimodal budgetary tradeoffs that will result from varying funding allocation and priority scenarios. MICA's methodology is based on benefit-cost and goal achievement analyses. The project has completed the first phase of research. The purpose of this two-volume report is to document the analysis methodology contained within the MICA program, as well as general findings from the first phase of this research effort. This document is also designed to serve as a User's Manual for operating the MICA program. While challenges still exist, the results of the Phase I research effort indicate that development of a multimodal analysis tool is feasible.

Authors:
Young,R., Barnes,J., Rutherford,G. S.

Keywords:
statewide programming, prioritization, multimodal, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/547.1.pdf http://wsdot.wa.gov/Research/Reports/500/547.1.htm
Young,R. WA-RD 547.2 Multimodal Investment Choice Analysis - Vol. II: Program Code 2002 TRAC/UW
Abstract:
The Multimodal Investment Choice Analysis (MICA) project is developing a computer-based tool to assist the Washington State Department of Transportation (WSDOT), the Washington State Transportation Commission, and the Washington State Legislature in making state transportation funding decisions. The function of MICA is to summarize the multimodal budgetary tradeoffs that will result from varying funding allocation and priority scenarios. MICA's methodology is based on benefit-cost and goal achievement analyses. The project has completed the first phase of research. The purpose of this two-volume report is to document the analysis methodology contained within the MICA program, as well as general findings from the first phase of this research effort. This document is also designed to serve as a User's Manual for operating the MICA program. While challenges still exist, the results of the Phase I research effort indicate that development of a multimodal analysis tool is feasible.

Authors:
Young,R., Barnes,J., Rutherford,G. S.

Keywords:
statewide programming, prioritization, multimodal, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/547.2.pdf http://wsdot.wa.gov/Research/Reports/500/547.2.htm
Woodruff,D. WA-RD 523.1 Mapping of Subtidal and Intertidal Habitat Resources: Hood Canal Floating Bridge, Washington 2002 TRAC/UW
Abstract:
The Washington State Department of Transportation is planning to repair and replace portions of the Hood Canal Bridge. To minimize construction impacts, it is important to spatially evaluate the location of biological resources, such as eelgrass (Zostera marina), geoduck clams (Panopea abrupta), and rockfish (Sebastes app.), near the bridge, particularly at the eastern and western termini, and associated construction sites.An underwater mapping effort was conducted during Janaury 2001, during a season noted for dieback of eelgrass and senescence, whereas CASI imagery was collected during the summer of 2000 when eelgrass cover was at a maximum. Although the two methods produced some minor differences in the eelgrass patch margins, the vast majority of the areas overlapped along the eastern terminus where both methods were employed. Hence, the resulting maps for both the eastern and western termini should be considered accurate delineations of eelgrass (cover type and geopositional accuracy). At both the eastern and western termini, close to the bridge, a general lack of eelgrass continuity was noted. However, continuous beds were mapped on both sides at varying distances from the bridge.The merged intertidal-subtidal eelgrass maps are the result of one of the first integrated mapping efforts of nearshore eelgrass in the Northwest. The spatially referenced data collected on substrate type, fish, and macroinvertebrates will allow examination of habitat usage in the future near the eastern and western termini of the bridge.

Authors:
Woodruff,D., Borde,A., Williams,G. D., Southard,J., Thom,R. M., Simenstad,C., Garono,R., Robinson,R., Norris,J.

Keywords:
eelgrass, underwater video, Hood Canal, CASI, hyperspectral, remote sensing, habitat assessment, GIS, research


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http://www.wsdot.wa.gov/research/reports/fullreports/523.1.pdf http://wsdot.wa.gov/Research/Reports/500/523.1.htm
Vu,P. WA-RD 554.1 Economic Impacts of Access Management 2002 TRAC/UW
Abstract:
Access management has been widely defined as the planning, design, and implementation of land-use and transportation strategies that control the flow of traffic between roads and surrounding land. Management and control of vehicular, pedestrian, bicycle, air, and sea traffic occurs through various forms of access, including traffic signals, turning lanes and restrictions, driveway spacing management, intelligent transportation systems, gating and hubbing schemes, and port terminal management. The engineering of transportation systems thus involves access management as a critical negotiations tool. Previous studies on access management have focused mainly on the positive benefits of access management relating to reductions in accident counts and severities, and improvement in traffic flow. However, the evolution of transportation systems design is also influenced greatly by the perceptions of system users, and to date, research on perceptions of access has been limited. User perceptions of access affect business vitality as well as residential quality of life. This study addressed the perceived economic impacts that access management has specifically on businesses. This study collected 280 surveys from businesses along six major commercial corridors in Western Washington, as well as business-related data from geographic information systems. The researchers then focused on statistical frameworks for analyzing perceived economic impacts. Perceived economic impact due to access management was first assumed and then later proven to correlate implicitly and explicitly to perception of accessibility for any given business. Model estimation was conducted by using joint density models to capture the perceptual inter-relationships between business accessibility and patronage. Factors found to be statistically significant included business type, business operational variables, corridor and street environment variables, and willingness-to-pay amounts. The identification of significant business factors offers insights into how businesses view access management. In the dialogue on design requirements between public development review units and private land developers, such information can provide a successful and efficient negotiations tool.

Authors:
Vu,P., Shankar,V., Chayanan,S.

Keywords:
access management, land use, economic impacts, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/554.1.pdf http://wsdot.wa.gov/Research/Reports/500/554.1.htm
Shafizadeh,K. WA-RD 538.1 A Statistical Analysis of Factors Associated with Driver-Perceived Road Roughness on Urban Highways 2002 TRAC/UW
Abstract:
This study linked physical quantitative roadway measures with subjective, driver-perceived measures of roughness on urban highways. 56 participants from the general public were placed in normal traffic conditions and asked their opinions about pavement roughness on 40 predetermined highway test segments. Driver evaluations were collected with other data, such as speed and in-vehicle noise, and matched with driver-specific socio-demographic data and pavement-specific data from the Washington State Department of Transportation and its pavement management system.Results from an ordered logit model indicated that the international roughness index (IRI) is the single best predictor of driver-perceived road roughness and driver acceptability. Pavements with low IRI values generally corresponded with low roughness rankings and high levels of user acceptability. Other factors statistically associated with driver-perceived measures of road roughness included measured IRI, the presence of pavement maintenance, the presence of joints or bridge abutments, the age of the pavement surface, the vehicle type, levels of in-vehicle noise, the speed of vehicle, and the gender and income of the driver.This study also provided empirical data that can be used to both support or challenge the federal IRI acceptability threshold of 170 in/mi (2.7 m/km) recommended by the Federal Highway Administration.

Authors:
Shafizadeh,K., Mannering,F. L., Pierce,L.

Keywords:
Pavement preservation, roughness, international roughness index, ride quality, pavement management systems, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/538.1.pdf http://wsdot.wa.gov/Research/Reports/500/538.1.htm
Scheibe,R. R. WA-RD 551.1 An Overview of Studded and Studless Tire Traction and Safety 2002 TRAC/UW
Abstract:
Studded tires have generated much controversy over the years; a number of states have banned them, while others, including Washington, have restricted their use and passed legislation to require lighter-weight studs. This report reviews recent studies that have addressed the performance and safety of the current generation of studded tires as well as the new "studless" winter tires on late-model vehicles. The well-documented correlation between studded tires and pavement wear was not the focus of this work.The issues surrounding studded tire performance and safety are complex. From the standpoint of traction alone, studded tires, when new, often provide some benefit over the other tire types on ice-covered roads when the temperature is near f reezing. However, the advent of the new studless tires has diminished the marginal benefit, and recent studies suggest that the infrequent, narrow range of conditions necessry for benefit from studded tires may not outweigh their detrimental effect on tracton in dry or wet conditions on certain pavement types. In addition, a host of primary and secondary safety factors are related to studded tire use, many of which are very difficult to quantify, including facets of driver behavior and safety perception.

Authors:
Scheibe,R. R.

Keywords:
studded tire, traction, performance, safety, winter, research, Kirkland


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/551.1.pdf http://wsdot.wa.gov/Research/Reports/500/551.1.htm
Sauer,G. WA-RD 552.1 Analysis of Web-Based WSDOT Traveler Information: Testing Users' Information Retrieval Strategies 2002 TRAC/UW
Abstract:
This report details the findings of a usability study for the Washington State Department of Transportation (WSDOT) of traffic and weather information on the Web. The purpose of this test was to examine the user experience associated with retrieving traveler information, such as road conditions, traffic congestion, pass information, construction, and weather, from the WSDOT Traffic and Weather site.

Authors:
Sauer,G., Kolko,B., Rose,E., Haselkorn,M.

Keywords:
usability testing, World-Wide Web, users' retrieval strategies, traveler information, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/552.1.pdf http://wsdot.wa.gov/Research/Reports/500/552.1.htm
Nihan,N. L. WA-RD 535.1 Evaluation of Dual-Loop Data Accuracy Using Video Ground Truth Data 2002 TRAC/UW/Trans/NOW
Abstract:
This study evaluated the accuracy of truck data collected by dual-loop detectors on the Seattle Area freeways. The objectives of the study were to 1) quantitatively evaluate the accuracy of a representative sample of dual-loop measurements of vehicle volumes and vehicle classifications on the Seattle FLOW system, 2) identify the types and causes of dual-loop data inaccuracies, and 3) recommend appropriate methods for improving the types and causes of dual-loop measurements.One representative station with four dual-loop detectors was selected for an extended error analysis. The detector measurements were compared to ground truck data collected via a video image system. Data for 20-second intervals were compared for peak and off-peak periods. Since there was no documentation on the settings of the dual-loop system clock, an independnent analysis was conducted to synchronize the dual-loop and video image systems clocks before analysis.ln general, three dual-loop error types were identified through comparison of dual-loop and video ground-truth data: (1) underestimation of vehicle volumes, (2) incorrect flagging of Bin 3 vehicles to Bin 4, (4) incorrect assignment of Bin 2 vehicles to Bins 1 and 3.Dual-loop measurement errors such as those described above may be due to defects in system hardware, software, or the underlying measurement algorithm. Because hardware errors were virtually eliminated as a factor in the current study, the serious errors that still occurred were most likely due to defects in the underlying dual-loop algorithm or in the implementation program. Therefore, to radically improve the quality of dual-loop data, and thus the quality of real-time truck data on the FLOW system, the WSDOT dual-loop algorithm and its corresponding implementation program should be the emphasis of future research.

Authors:
Nihan,N. L., Zhan,X., Wang,Y.

Keywords:
dual-loop detectors, vehicle volumes, vehicle classification, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/535.1.pdf http://wsdot.wa.gov/Research/Reports/500/535.1.htm
Moudon,A. V. WA-RD 556.1 Pedestrian Safety and Transit Corridors 2002 TRAC/UW
Abstract:
This research examines the relationship between pedestrian accident locations on state owned facilities (highways and urban arterials) and the presence of riders loading and alighting from bus transit. Many state facilities are important metropolitan transit corridors with large numbers of bus stops users, so that these facilities have higher pedestrian exposure to traffic and an increased number of collisions. The research also examines the association between pedestrian collisions and other pedestrian travel generators, such as concentrations of retail activity and housing, as well as environmental conditions such as wide roadways, high traffic volumes, and high speed limits.On the basis of a retrospective sampling approach and logistic regression models, the study shows that bus stop usage is strongly associated with pedestrian collisions along state facilities. Less strong, but significant associations are shown to exist between retail location and size, traffic volume, and number of traffic lanes, and locations with high levels of pedestrian-vehicle collisions. The findings suggest that facilities with high numbers of bus riders need to accommodate people walking safely along and across the roadway. They support the development of state DOT programs for multi-modal facilities that integrate travel modes in major regional facilities within local suburban communities and pay specific attention to the role of transit in shaping the demand for non-motorized travel on the facilities. Also, state DOT, local jurisdiction, and transit staff must work together to identify facilities and locations where bus riders are at risk and take appropriate steps to ensure pedestrian safety.

Authors:
Moudon,A. V., Hess,P.

Keywords:
multimodal facilities, pedestrian collisions, pedestrian safety, research, transit


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/556.1.pdf http://wsdot.wa.gov/Research/Reports/500/556.1.htm
Miller,M. C. WA-RD 521.2 Effects of Shoreline Hardening and Shoreline Protection Features on Fish Utilization and Behavior at Washaway Beach, Was... 2002 Washington State Deptartment of Transportatio
Abstract:
This report is the second in a series of reports detailing the procedures used and the results obtained from studies designed to determine the impacts of erosion control structures on habitat at Willapa Bay, Washington. The erosion control structure, consisting of a 1600-ft rock groin and an attached 930-ft underwater dike was placed on Washaway Beach in 1998 to protect State Route (SR) 105 from erosion. The project background is more fully described in Phillips and Pierce (1999). The location and general layout of the area surrounding the rock groin is locally known as "Jacobson's Jetty."The objectives of the study are to develop an understanding about whether groin-type structures on the outer coast can alter migratory movement or predation pressure on juvenile and adult salmon. The Washaway Beach dike and groin structure is an example of such a feature and provides an opportunity to conduct coupled studies on the physics and associated ecology of these sructures in this environment.

Authors:
Miller,M. C., Williams,G. D., O'Rourke,L. K., Southard,J. A., Slanton,S. L.

Keywords:
research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/521.2.pdf http://wsdot.wa.gov/Research/Reports/500/521.2.htm
Massman,J. WA-RD 533.1 Infiltration Characteristics, Performance and Designs of Stormwater Facilities 2002 TRAC/UW
Abstract:
Storm water infiltration facilities help reduce the hydrologic impacts of residential and commercial development. The design of these facilities is particularly challenging because of large uncertainties associated with predictions of both short-term and long-term infiltration rates.Full-scale "flood tests" conducted at four infiltration facilities in western Washington suggest that lateral flow along the sides of the ponds may be significant. This is similar to "bank storage" that occurs in stream channels. More efficient designs may require a larger ratio of side area to bottom area and that maintenance activities should be considered for the sides as well as the bottom of the pond. Saturated hydraulic conductivity values estimated from measuring air conductivity and from regression equations derived from grain size parameters were compared to full-scale infiltration rates for 15 sites in western Washington. The estimated values for saturated hydraulic conductivity were up to two orders-of-magnitude larger than the full-scale infiltration rates for some sites and were two orders-of-magnitude smaller at others. These results show that infiltration rates cannot be reliably estimated on the basis of soil properties alone; information related to the hydraulic gradient is also important. Computer models were compared to identify the flow systems for which saturated models provide reasonable approximations. The difference between saturated and unsaturated flow models was lowest in highly permeable soils and increased as the hydraulic conductivity of the soil decreased. The simulations suggest that steady-state infiltration rates calculated with a saturated model will be 20 to 40% smaller than rates calculated with an unsaturated model for the range of hydraulic conductivities typically found beneath Western Washington infiltration ponds. A comparison of steady-state and transient simulations showed that the steady-state assumption may significantly under-estimate infiltration rates.

Authors:
Massman,J., Butchart,C. D., Stolar,S.

Keywords:
stormwater infiltration facilities, infiltration rates, hydraulic conductivity estimates, full-scale infiltration tests, numerical similations, research


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Ishimaru,J. M. WA-RD 555.1 North Seattle Advanced Traffic Management System (NSATMS) Project Evaluation 2002 TRAC/UW
Abstract:
This report documents the findings of the evaluation of the North Seattle Advanced Traffic Management System (NSATMS) Project. The evaluation was originally designed to analyze the potential transportation benefits and costs of a regional arterial traffic data sharing system that would obtain traffic signal system information (volumes, signal timing plans, etc.) from participating agencies and then share the data among those agencies. The operational goal was to allow each agency to make better control decisions by providing it with real-time knowledge of traffic conditions outside of its own control system boundaries. Because of a series of technical and project management issues, the system as originally envisioned was not successfully implemented. As a result, this evaluation does not include an analysis of direct operational benefits. It does, however, include a discussion of the expected institutional benefits, as well as an extensive "lessons learned" section based on the project team's review of the NSATMS effort. Of particular note were the importance of effective and ongoing lines of project communication, and the critical need to properly evaluate the fundamental nature of the project and provide a well-matched project management structure. The lessons learned from this project provide instructive guidelines for those who are contemplating future ITS system development efforts of comparable scope and complexity. Despite the limited successes of the NSATMS effort, the evaluation team found continued support for the regional arterial ATMS concept within the Puget Sound region. Follow-on research that contributes to a better understanding of the benefits, costs, and technical requirements of an arterial traffic management system is desired by many of the project participants.

Authors:
Ishimaru,J. M., Hallenbeck,M. E.

Keywords:
intelligent transportation systems, advanced traffic management systems, arterial signal control systems, traffic control strategies, Archived Data User Services (ADUS), data sharing, evaluation, seattle, advanced traffic management systems, traffic, traffic management, management, management system, transportation, transportation benefit, benefits, benefit, costs, cost, arterial, traffic data, data, volume, control, condition, ITS, project management, analysis, line, development, ATMS, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/555.1.pdf http://wsdot.wa.gov/Research/Reports/500/555.1.htm
Holtz,R. D. WA-RD 532.1 Internal Stability Analyses of Geosynthetic Reinforced Retaining Walls 2002 TRAC/UW
Abstract:
This research project was an effort to improve our understanding of the internal stress-strain distribution in GRS retaining structures. Our numerical modelling techniques utilized a commercially available element program, FLAC (Fast Lagrangian Analysis of Continua). In this research, we investigated and appropriately considered the plane strain soil properties, the effect of low confining pressure on the soil dilation angle, and in-soil and low strain rate geosynthetic reinforcement properties.Modeling techniques that are able to predict both the internal and external performance of GRS walls simultaneously were developed. Instrumentation measurements such as wall deflection and reinforcement strain distributions of a number of selected case histories were successfully reproduced by our numerical modeling techniques. Moreover, these techniques were verified by successfully performing true "Class A" predictions of three large-scale experimental walls.An extensive parametric study that included more than 250 numerical models was then performed to investigate the influence of design factors such as soil properties, reinforcement stiffness, and reinforcement spacing on GRS wall performance. Moreover, effects of design options such as toe restraint and structural facing systems were examined. An alternative method for internal stress-strain analysis based on the stress-strain behavior of GRS as a composite material was also developed. Finally, the modeling results were used to develop a new technique for predicting GRS wall face deformations and to make recommendations for the internal stability design of GRS walls.

Authors:
Holtz,R. D., Lee,W. F.

Keywords:
analysis, behavior, design, experimental, FLAC, geosynthetic, geotechnical, materials, modeling, models, performance, prediction, pressure, program, reinforcement, research, retaining wall, retaining walls, stability, structures, systems, walls


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/532.1.pdf http://wsdot.wa.gov/Research/Reports/500/532.1.htm
Hallenbeck,M. E. The Concurrency Calculation Process -- Current Procedures and Potential Alternatives 2002 TRAC/UW
Abstract:
This report serves three functions. First, it meets the requirement for Technical Memorandum #2, a report on state, regional, and local concurrency systems and practices. Second, it fulfills the reqirement for Technical Memorandum #4 on issues identification. Last, it presents an initial review of alternative approaches to changing or refining the concurrency practices currently used by some of the participating agencies.The first section of this report briefly describes how concurrency is calculated. The second section describes the limitations of those procedures and highlights important issues raised by project stakeholders that should be addressed in changes to the current system. The third section presents a preliminary review of alternatives that are being considered in the near term to replace or refine the current process. This specific list of alternatives was included in the original scope of work by the four cities. They are briefly analyzed for implementation in the near term. It is the project team's opinion that none of these solutions resolve the larger issues identified in the second section of this report. As a result, additional approaches to concurrency need to be considered by the four cities if they wish to resolve these issues. The fourth and final section of this report briefly identifies the primary subject areas that need further investigation if the project team is to develop functional alternatives to the current concurrency process that address the limitations in the second section of this report.The four cities (Bellevue, Issaquah, Kirkland, Redmond) participating in this project use concurrency determination procedures that are similar in style and structure but that differ in technical execution.

Authors:
Hallenbeck,M. E., Carlson,D., Simmons,J.

Keywords:
Concurrency, research

Haas,M. E. WA-RD 550.1 Effects of Large Overwater Structures on Epibenthic Juvenile Salmon Prey Assemblages in Puget Sound, Washington 2002 TRAC/UW
Abstract:
Although large over-water structures alter nearshore habitat in a number of ways, little work has been done to study how docks affect nearshore fauna. In Puget Sound, juvenile chum, pink, and ocean-type chinook salmon migrate along the shorelines and feed extensively on shallow water epibenthic invertebrates. As part of an ongoing project on the effects of ferry terminals on juvenile salmon, this study looked at the effects of large overwater structures on juvenile salmon and their prey. The epibenthic assemblage was sampled for juvenile salmon prey with four sampling regimes: monthly-stratified sampling of epibenthic invertebrates at three terminals, one-time eelgrass patch at a single terminal, one-time high-resolution cross-terminal at a single terminal, and one-time terminal structure sampling at two terminals. The response variables tested included taxa richness and densities of (1) total epibenthos, (2) total juvenile salmon prey,(3) common or abundant salmonprey taxa and (4) common or abundant non-salmon prey taxa.Both the stratified-monthly and eelgrass sampling indicated that terminals negatively affected all summary response variables and many individual taxa. High-resolution cross-terminal sampling results were less clear, but the negative impacts of the terminal were evident for some taxa. Finally, terminal structure sampling results showed some differences in assemblages on different structure-types and elevations, and an overall smaller abundance of epibenthos on terminal structures than on intertidal sediment and benthic vegetation. In general, these results agreed with impact predictions based on vessel disturbance (propeller wash) and shading of benthic vegetation, and with assessments of these attributes completed during the sampling season. The researchers concluded that decreases or changes in the epibenthos density, diversity, and assemblage at these large overwater structures were probably caused by four interacting factors: direct disturbance or removal by vessel traffic, reduced or compromised benthic vegetation, physical habitat alterations, and biological habitat alterations.

Authors:
Haas,M. E., Simenstad,C. A., Cordell,J. R., Beauchamp,D. A., Miller,B. S.

Keywords:
overwater structures, ferry terminals, nearshore habitat, juvenile salmon, epibenthic assemblage, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/550.1.pdf http://wsdot.wa.gov/Research/Reports/500/550.1.htm
Glad,R. W. WA-RD 516.1 Median Treatment Study on Washington State Highways 2002 Washington State Dept. of Transportation
Abstract:
Across the median crashes are high severity, often fatal crashes occuring when errant vehicles cross the median and enter the opposing lanes of travel. Guidelines for the installation of median barriers presented in the AASHTO Roadside Design Guild were developed in the 1960's. A study of across the median crashes on Washington's multilane, divided state highways, with full access control, was conducted to evaluate median barrier guidelines and identify specific highway sections where installation of a barrier is desirable. A benefit/cost analysis was conducted to evaluate the cost of effectiveness of median barrier installation. The analysis was used to develop revised guidelines for median barrier installation. In addition, the benefit/cost methodology provides a means for ranking median barrier needs based on past crash history. This ranking will allow these improvements to compete for safety improvement funds.

Authors:
Glad,R. W., Albin,R. B., McIntosh,D. M., Olson,D. K.

Keywords:
across-the-median crashes, median, median barrier, concrete barrier, cable barrier, guardrail, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/516.1.pdf http://wsdot.wa.gov/Research/Reports/500/516.1.htm
Dailey,D. J. WA-RD 537.1 A Cellular Automata Model for Use with Real Freeway Data 2002 TRAC/UW
Abstract:
The exponential rate of increase in freeway traffic is expanding the need for accurate and realistic methods to model and predict traffic flow. Traffic modeling and simulation facilitate an examination of both microscopic and macroscopic views of traffic flows and are therefore considered one of the most important analytical tools in traffic engineering. This report presents a cellular automata model for traffic flow simulation and prediction (CATS). Cellular automata models quantize complex behavior into simple individual components. In this model, the freeway being simulated is discretized into homogeneous cells of equal length, and time is discretized into timesteps of equal duration. The CATS model allows users to define locations within the road topology where volume and density data will be calculated so that the model results can be compared to observed highway data.

Authors:
Dailey,D. J., Taiyab,N.

Keywords:
cellular automata, traffic modeling, dynamic simulation, prediction, control, ramp metering, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/537.1.pdf http://wsdot.wa.gov/Research/Reports/500/537.1.htm
Dailey,D. J. WA-RD 484.1 Traffic Data Acquisition and Distribution (TDAD) 2002 TRAC/UW
Abstract:
The wide variety of remote sensors used in Intelligent Transportation Systems (ITS) applications (loops, probe vehicles, radar, cameras, etc.) has created a need for general methods by which data can be shared among agencies and users who own disparate computers systems.In this report, we present a methodology that demonstrates that it is possible to create, encode, and decode a self-describing data stream using the following: 1. existing data description language standards 2. parsers to enforce language compliance 3. a simple content language that flows out of the data description language 4. architecture neutral encoders and decodes based on ASN.1

Authors:
Dailey,D. J., Myers,D., Pond,L., Guiberson,K.

Keywords:
travel time, data mine, JDBC, data user services, ADUS, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/484.1.pdf http://wsdot.wa.gov/Research/Reports/400/484.1.htm
Dailey,D. J. WA-RD 534.1 AVL-Equipped Vehicles as Traffic Probe Sensors 2002 TRAC/UW/TransNow
Abstract:
In this report, we present new algorithms that use transit vehicles as probes to determine traffic speeds and travel times along freeways and other primary arterials. We describe a mass transit tracking system based on automatic vehicle location (AVL) data and a Kalman filter to estimate vehicle position and speed. We also describe a system of "virtual" probe sensors that measure transit vehicle speeds using the track data. Examples showing the correlation between probe data and inductance loop speed trap data are presented. We also present a method that uses probe sensor data to define vehicle speed along an arbitrary roadway as a function of space and time, a speed function. We present the use of this speed function to estimate travel time given an arbitrary starting time. Finally, we introduce a graphical application for viewing real-time speed measurements from a set of virtual sensors that can be located throughout King County on arterials and freeways.

Authors:
Dailey,D. J., Cathey,F. W.

Keywords:
automatic vehicle location (AVL), kalman filter, transit vehicles, speed sensors, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/534.1.pdf http://wsdot.wa.gov/Research/Reports/500/534.1.htm
Dailey,D. J. WA-RD 543.1 A Brief Report on 2001 Activities for ITS Backbone Infrastructure 2002 TRAC/UW
Abstract:
The ITS Backbone performs several important tasks for ongoing efforts at the Washington State Department of Transportation and University of Washington. The Backbone (1) supports existing traveler information applications for both traffic and transit information, (2) supports real-time access to WSDOT data for a variety of public and private groups, (3) off-loads the interaction and support of data users external to WSDOT, (4) provides a standard interface so that all roadway data are available equally to outside agencies/groups, (5) supports research activities within WSDOT, research funded by WSDOT at the UW, and research at universities and agencies nationwide, and (6) provides a standard interface to include new data sources into the existing traffic management system.

Authors:
Dailey,D. J.

Keywords:
intelligent transportation systems, backbone, real-time data, standard interface, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/543.1.pdf http://wsdot.wa.gov/Research/Reports/500/543.1.htm
Casavant,K. L. WA-RD 540.1 Methodology for Determining Washington State Value-Added of Freight Moved in Washington Corridors 2002 TRAC/WSU
Abstract:
Determining the marginal value of improved freight mobility along with a corridor requires full information on tonnage, dollar value of freight movements and services used in moving these products and the value-added characteristics of those products. This report investigates whether a practical methodology, applicable in the real world, can estimate value-added components of freight moving on Washington's transportation system. Determining this value-added can be done with the methodology identified in this study though it was found that specific data availability varied heavily from commodity to commodity, from corridor to corridor and project to project. The general results, and restructive assumptions and data deficiencies necessary for statewide analysis, cast doubt on specific findings. Regional or highway segment analysis can be more precise, if the data are locally developed. The basic model, consisting of kowledge about traffic levels, commodity composition, commodity value and value added of the commodity can reveal the importance of a corridor or region of interest to the state's economy.

Authors:
Casavant,K. L., Sorensen,P., Chase,B.

Keywords:
freight, value-added, Washington, methodology, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/540.1.pdf http://wsdot.wa.gov/Research/Reports/500/540.1.htm
Casavant,K. L. WA-RD 557.1 Functions and Benefits of Rural Airports in Washington 2002 TRAC/WSU
Abstract:
The economic benefits of major airports are well known and acknowledged; less well known is the benefit to the state and rural communities provided by rural airports. The rural airport system, and its users, are caught on the horns of a dilemma. The need for local airport services is never more critical but the vitality of the rural Washington airport system, and the capability to support that system, does not mirror the past vigor of the state economy. This report identifies the wide range of benefits that rural communities receive because they have an airport. The study used a qualitative research framework, combining individual inerviews and available literature to identify "emerging themes" of airport activities. These themes are: Economic Development and Airports--The Box That Must Be Checked; Health Care --Emergency Service; Business and Commerce; Public Safety, Disaster and Emergency Response; and Enriching Community Life. For those policy makers and citizens concerned about the future of rural communities, the future of rural airports must be given attention. This study's results support their role as an essential public facility.

Authors:
Casavant,K. L., Newkirk,J.

Keywords:
airports, aviation, benefits, general aviation, research, rural


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/557.1.pdf http://wsdot.wa.gov/Research/Reports/500/557.1.htm
Boon,C. B. WA-RD 529.1 Road Weather Information Systems (RWIS): Enabling Proactive Maintenance Practices in Washington State 2002 TRAC/UW
Abstract:
Washington State Department of Transportation's (WSDOT) rWeather program has significantly integrated and expanded the capabilities of road weather information systems (RWIS) in the state, enabling proactive winter maintenance practices and better informed winter travel decisions. The report reviews the potential benefits of a comprehensive, integrated RWIS, including cost-efficient snow and ice control strategies and improved safety and mobility. Use of, and attitudes toward, RWIS by WSDOT maintenance personnel are examined, and barriers to the expanded use of RWIS technologies are identified. Public response to the rWeather traveler information website is evaluated. Recommendations are presented for more fully utilizing RWIS capabilities.

Authors:
Boon,C. B., Cluett,C.

Keywords:
Road Weather Information System, RWIS, winter maintenance, snow and ice control, traveler information, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/529.1.pdf http://wsdot.wa.gov/Research/Reports/500/529.1.htm
Bolton,S. M. WA-RD 539.1 Juvenile Coho Movement Study 2002 TRAC/UW/Center for Streamside Studies/Battell
Abstract:
This pilot study was initiated to investigate movement patterns, habitat utilization, and velocity preferences for young of the year coho salmon (Oncorhynchus kisutch) during the spring in Western Washington and examine potential factors controlling redistribution timing in the fall. Water velocity appeared to be an important factor in predicting juvenile coho (< 55 mm) distribution. Mark-recapture studies indicated that upstream movement by juvenile coho through culverts is low. Timing for fall redistribution of juvenile coho from main channels into off-channel habitat was investigated in relation to water temperature, stream flow, date, and moon phase. The majority of movement by juvenile coho in the Skagit, Suiattle, and Stillaguamish River basins occurred during new and half moon phases. Movement into off-channel habitat by juvenile coho in the Hoh River basin corresponded with floods where flow increased by 2000 cubic feet per second (cfs) and coincided with a new moon. Studies at Remote Site Incubators, indicate that recently emerged coho fry move up and downstream. Upstream movement ranged between 100 and 200 meters from April through June. After June, coho fry were found over 500 m upstream.

Authors:
Bolton,S. M., Moss,J., Southard,J., Williams,G. D., DeBlois,C., Evans,N.

Keywords:
juvenile coho salmonids, movement patterns, velocity, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/539.1.pdf http://wsdot.wa.gov/Research/Reports/500/539.1.htm
Blanton,S. L. WA-RD 525.1 Evaluation of Methods to Increase Light Under Ferry Terminals 2002 Battelle Marine Sciences Laboratory//Battelle
Abstract:
To address concerns of resource agencies about the potential impacts of ferry terminal expansion on valuable habitat functions and resource use of nearshore areas, the Pacific Northwest National Laboratory (PNNL), in partnership with the Washington State Department of Transportation (WSDOT), conducted field trials with off-the-shelf products that promote light passage through dock structures. These products included a SunTunnel(TM), deck prisms, and a metal halide greenhouse light. Light measurements (photosynthetically active radiation, PAR), were also recorded beneath glass blocks and a metal grating installed at Clinton Ferry Terminal on Whidbey Island, Washington. A review of other studies measuring the effects of dock shading and alternate dock materials was conducted.PAR measurements from this study were related to minimum requirements for eelgrass Zostera marina photosynthesis and to the known maximum photosynthetic "saturation" rate for Z. marina. We also related PAR measurements to what we know about light requirements for macroalgae and kelp, and light effects on juvenile salmonid feeding and passage under overwater structures. All of the light technologies tested could provide enough light for eelgrass growth underneath a ferry terminal that is being expanded or rebuilt if certain requirements are met. For example, all of the technologies (some signgly and some in multiples) could provide adequate light for eelgrass if the dock is no greater than 15 ft. above the eelgrass and certain air:water ratios are met. At increased distances between the deck and eelgrass, the air:water ratio and total distance light must travel begin to limit the technolgies that could successfully be applied. In general, the products predicted to provide the most to the least light to eelgrass are the grating, SunTunnel, metal halide greenhouse light, and prisms. Light levels required to allow fish to feed and to form schools are low , and much less than those required for photosynthesis (Ali 1959). Based on Ali's data, our research indicates that installing any of the tested light products would likely maintain light levels under the dock above those required for active feeding by juvenile salmonids.

Authors:
Blanton,S. L., Thom,R. M., Borde,A., Diefenderfer,H., Southard,J.

Keywords:
light, overwater structure, nearshore habitat, photosynthesis, salmonids, eelgrass, transportation, highway, port, Washington, research


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Arduino,P. WA-RD 514.1 Dynamic Stiffness of Piles in Liquefiable Soils 2002 TRAC/UW
Abstract:
This research developed tools and procedures for evaluating the stiffness of pile foundations in liquefiable soils during earthquakes. Previous research on dynamic stiffness performed for the Washington State Department of Transportation resulted in the development of a Manual that provided simple charts for estimating the stiffnesses of typical pile foundations in soil deposits typical of those encountered in Washington state. The tools and procedures developed in the current project were based on up-to-date models for liquefiable soil and for soil-pile interaction, which obviated the need for many of the simplifying assumptions used in the Manual. The tools were developed by updating and extending the capabilities of two computer programs developed in part during previous WSDOT research studies.A greatly improved model for describing the seismic response of liquefiable soil was implemented into a nonlinear, effective stress site response analysis (WAVE). This model, termed the UWsand model, allows estimation of the response of typical sands to the stresses induced by earthquake shaking. The model has the important advantage of being easily calibrated with commonly available data. It captures important aspects of the behavior of liquefiable soils, including the phase transformation behavior associated with cyclic mobility that strongly influences free-field response and soil-pile interaction. The model has been successfully validated against field observations of soil liquefaction.Soil-pile interaction analyses were performed with an extended version of the program DYNOPILE. DYNOPILE was modified to allow different pile head loading conditions, including the attachment of a single-degree-of-freedom structure to the pile head to allow coupled analysis of soil-pile-structure interaction. A Windowsbased version of DYNOPILE was developed.The modified WAVE and DYNOPILE programs were used to improve and extend the stiffness charts for liquefiable soils that were presented in the Manual. WAVE and DYNOPILE can also be applied to site-specific evaluation of dynamic pile stiffness by using the same procedures used to develop the improved charts.

Authors:
Arduino,P., Kramer,S. L., Ping,L., Baska,D. A.

Keywords:
piles, liquefaction, foundation stiffness, foundation damping, lateral spreading, seismic response, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/514.1.pdf http://wsdot.wa.gov/Research/Reports/500/514.1.htm
Taylor,R. S. WA-RD 509.1 Maintaining Freight Mobility Options in Washington State: Innovative Approaches to Preserving Rail Freight Service 2001 Wilbur Smith Associates/WSDOT
Abstract:
Since 1970, the Washington State's rail system has shrunk from approximately 5,008 route miles to 3,123 miles. Many rural communities and shippers no longer have rail service due to rail line abandonments. Of the remaining rail system in the state, approximately 1,600 miles are light density rail lines that are most vulnerable to abandonments. This document reports the results of a study of means of preserving service on these potentially endangered rail lines.The changing nature of the rail system, both nationally and in Washington state, is documented along with what these changes mean to the public and system stability. The reasons rail line are abandoned are reviewed and the revenue-cost relationship, the heart of the issue, is discussed at some length including how adjustments in both revenues and costs can impact line viability. Public assistance forms and availability are documented as are the existing and potential roles of various public bodies at both the state and local level. Findings are summarized, conclusions reached , stated, and recommendations made.

Authors:
Taylor,R. S.

Keywords:
rail service, rail line abandonments, research


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/509.1.pdf http://wsdot.wa.gov/Research/Reports/500/509.1.htm
Roeder,C. W. WA-RD 494.1 Fatigue Cracking of Riveted, Coped, Stringer-to-Floorbeam Connections 2001 TRAC/UW
Abstract:
Fatigue cracking has been noted in a number of riveted, coped stringer-to-floorbeam connections on truss bridges in Washington state. The fatigue cracking has raised uncertainty regarding the future performance and life expectancy of these bridges. This laboratory experimental research study evaluated the expected performance of these critical connections to better understand the causes of the fatigue cracking and to compare and evaluate several damage limitation methods for this critical location.Sixteen test specimens were built and tested. During the initial testing, the goal was to develop fatigue cracks in the region of the cope. The cracks were observed, and the rate of crack growth was closely monitored. The results of this work showed that the rate of initial visible cracking is dependent on the surface condition of the cope. Rough or notched copes develop cracks after a very few cycles. Once the crack has developed, the rate of crack growth does not depend on the surface condition of the cope.A damage limitation method (DLM) was applied to most specimens. Three methods--the hole drilling method, the drilled hole with inserted bolted, and the bolt removal method--were evaluated. After the DLM was applied, the specimen was retested to determine whether and when further crack growth occurred. The rate of crack growth was closely monitored, and the relative effectiveness of alternative DLMs were determined.A design and evaluation procedure was developed for predicting the time required for crack development and for selecting appropriate connection stiffnesses for application of the DLMs. This method utilizes load spectra developed in previous field investigations and methods for translating the load spectra into an effective stress and number of cycles for the fatigue evaluation. Models are provided for evaluating connection stiffness and for analyzing the effect of the connection stiffness on the stringer moments.

Authors:
Roeder,C. W., MacRae,G. A., Kalogiros,A. Y., Leland,A.

Keywords:
coped stringers, damage limitation, fatigue, fatigue cracking, fatigue life, repair, riveted connections, research


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Nee,J. WA-RD 510.1 Surveillance Options for Monitoring Arterial Traffic Conditions 2001 TRAC/UW
Abstract:
The interest in and need for monitoring and reporting on arterial traffic conditions have increased with the growing implementation of both traffic management and traveler information systems. Because an increasing number of travelers are turning to the Internet for information, agencies are seeking ways to present arterial traffic data on this medium that are both understandable and useful to the public. At the same time, these same data must provide additional operational insight to public agency traffic management staff. However, although the idea of reporting arterial conditions is similar to that of monitoring and reporting freeway traffic conditions, different and innovative methods appear necessary for arterials because freeways and arterials differ in many aspects, particularly the effects of signals on traffic flow and speed.The research approach for this project consists of a literature search, a series of personal interviews, and the development and user testing of alternative Internet-based information displays. The results of the study confirm that jurisdictions have a high level of interest in obtaining arterial traffic condition information for both arterial management and public information purposes. However, existing sensor coverage and equipment capabilities, as well as the manner in which data are (or are not) captured, require that much work be done before existing data sources can supply traffic data to Internet-based display systems. The study results provide some basic guidelines agencies can follow to obtain traffic information if no existing data sources are available, along with recommendations for presenting that arterial traffic data to the public.

Authors:
Nee,J., Hallenbeck,M. E.

Keywords:
arterial traffic information, surveillance, traffic monitoring, research


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Nee,J. WA-RD 518.1 Evaluation of the Service Patrol Program in the Puget Sound Region 2001 TRAC/UW
Abstract:
The Service Patrol pilot demonstration in Seattle and Tacoma was managed by the Washington State Department of Transportation (WSDOT) and operated by Washington State Patrol (WSP) cadets and contracted registered tow truck operators (RTTOs). Two other roving services, not funded as part of this pilot effort but included to a limited extent in this evaluation, were the roving patrol service provided by WSDOT on the SR 520 and I-90 floating bridges and the privately sponsored motor assistance vehicle from AAA's RescueVan. The evaluation examines how the similarities and differences among the different service delivery modes (e.g., the intensity of deployment, equipment choices, service delivery, costs) affect the impact of the Service Patrol operation on traffic conditions (e.g., reductions in delay) and the level of motorist satisfaction. This report also discusses feedback by the agencies participating in the Service Patrol program on institutional and operational issues that contribute to or hinder the success of the program. Operational characteristics and operating statistics are reported to convey factors that describe program effectiveness. The results of the study indicate that the use of a combination of service providers has benefits that no single provider can duplicate, and the cost implications of changing the program are small enough that any potential savings would be fairly minor. The pilot project resulted in a variety of intangible benefits, such as improved interagency coordination and cooperation, more efficient utilization of personnel, and a better understanding of each partner's roles and contributions toward congestion relief. The positive viewpoint toward the Service Patrol was uniform, regardless the service mode. Therefore, no significant changes to the existing pilot program are recommended at this time.

Authors:
Nee,J., Hallenbeck,M. E.

Keywords:
service patrols, incident response time, traffic delay, traffic safety, research, seattle, Washington, Washington state, transportation, WSDOT, truck, evaluation, floating bridge, bridges, bridge, costs, cost, traffic, condition, program, statistics, benefits, benefit, congestion


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Muench,S. T. WA-RD 517.1 A Quantification and Evaluation of WSDOT's Hot-Mix Asphalt Concrete Statistical Acceptance Specification 2001 TRAC/UW
Abstract:
This report clarifies the Washington State Department of Transportation (WSDOT) hotmix asphalt (HMA) statistical acceptance specification's statistical basis and how its key components influence overall specification performance and contractual pay.The WSDOT specification uses a variable sampling plan to measure in-place density, asphalt content, and aggregate gradation. Specification bands on these three quality characteristics are reasonable and consistent with typical material, sampling, testing, and construction variability. Pay is determined by calculating a percentage within limits (PWL), then applying a series of parabolic pay equations, depending on sample size.The methods used by WSDOT balance risk between the contractor and WSDOT well but result in two issues that differ from similar specifications: (1) expected pay for material produced at acceptable quality level (AQL) is greater than 1.0, and (2) WSDOT's AQL is 95 PWL but contractors seem to consistently produce material near 90 PWL The issues are not critical, and therefore, the specification should not be changed. However, if the third and final report in this series, which studies quality characteristics to be measured for Superpave design mixes, results in major recommended changes, then we recommend reviewing the AQL and pay factors to bring the specification into fine with actual practice.

Authors:
Muench,S. T., Mahoney,J. P.

Keywords:
asphalt concrete, HMA, hot mix asphalt, pay factor, research, specification, statistical acceptance specification, statistics, Washington state


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Moudon,A. V. WA-RD 519.1 Targeting Pedestrian Infrastructure Improvements: A Methodology to Assist Providers in Identifying Suburban Locations wi... 2001 TRAC/UW
Abstract:
This project yielded three tools for allocating investments to improve pedestrian infrastructure. The tools are tailored to suburban clusters and corridors where past research has shown that the potential exists for substantial volumes of pedestrian travel. The first two tools, Pedestrian Location Identification (PLI) tools 1 and 2, help differentiate between suburban areas that do and do not have potential for pedestrian travel. The third tool, Pedestrian Infrastructure Prioritization (PIP) Decision System, supports decisionmaking processes to allocate investments in infrastructure improvement to areas that do have potential for pedestrian travel. The tools generally yield benefits at the policy, implementation, and scientific levels.PLI-1 and PLI-2 focus on medium-density residential land development, areas that have been neglected in the past as locations with potential for pedestrian travel. By considering combinations of land uses that are generators and attractors of pedestrian travel, they capture the characteristics of land-use mixes that have the highest potential for substantial volumes of pedestrian trips. By using small spatial units of land-use data, they adequately capture the characteristics of actual development on the ground and, specifically, those characteristics that support pedestrian travel. The small units of data also allow a precise and accurate measurement of the land-use characteristics of the small areas that correspond to shortwalking distances.PIP is a synthesis of previous efforts to identify the environmental and policy variables that affect pedestrian travel. It acknowledges three types of environmental factors known to affect pedestrian travel demand: area-wide characteristics defined by land uses and development patterns, characteristics of the transportation facilities, and policies that determine the level of support for pedestrian travel. PIP provides a complete yet flexible framework for making decisions regarding infrastructure. It allows jurisdictions to work with their own internal set of priorities.

Authors:
Moudon,A. V.

Keywords:
pedestrian travel, pedestrian infrastructure, suburban, prioritization, research


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Miller,M. C. WA-RD 521.1 Effects of Shoreline Hardening and Shoreline Protection Features on Fish Utilization and Behavior, Washaway Beach, Washi... 2001 WSDOT
Abstract:
The shoreline in the vicinity of Cape Shoalwater, Pacific County, Washington, has been undergoing extreme erosion for nearly a century. With a shoreline retreat rate that has averaged between 100 and 130 feet per year, the site has been identified as having the most severe erosion rate of any location on the US West Coast. In 1998, the Washington State Departmet of Transportation constructed a groin and dike along the North Channel at North Cove in an attempt to halt and possibly reverse the erosion trend and to protect State Route 105, which was threatened by the northward migration of the channel.The emergency project was completed in November 1998. The structures placed on the site consisted of a 1600 ft rock groin extending on an approximate N-S line from SR 105 and attached to a 930 ft underwater dike, aligned perpendicular to the navigation channel. These were designed to slow erosion and facilitate accretion of sediments along the most vulnerable section of the highway. In addition, a beach nourishment was undertaken in which 350,000 cy of sand was placed on the beach, along the existing riprap wall immediately seaward of the highway and to the east of the structure which is locally known as Jacobson's Jetty.Placement of the structure and fill has raised concerns about impacts on the biota residing in or transiting the area, particularly the loss of habitat for the brown pelican and snowy plover, and destruction of Dungeness crab through dredging of beach nourishment material. Concern has also been expressed that construction of the rock structures may have altered the nearshore migration pattern of out-migrating juvenile salmon. The juveniles may be forced to swim into deeper water around the end of the structure, where they could be more susceptible to predation by birds, mammals, and fish. It was also felt that the rock structures and embayment might increase the density of salmon predators such as lingcod, scuplins, cabezon, and seals. Sand was initially placed over the groin to fill the void space betwen the large rocks and thus discourage the use of the groin by predatory fish. However, the fill was quickly washed away during the storms in the winter of 1998-99.The Federal Highway Administration (FHWA) and WSDOT entered into an agreement with other state and federal resource agencies and the Shoalwater Tribe to pursue environmental issues in an adaptive framework. To this end, bird monitoring has commenced and Dungeness crab impacts are being mitigated through placement of oyster shell within Willapa Bay.The potential impacts of erosion control structures on habitat, particularly in regard to salmon and other ESA listed or threatened species, is of concern to WSDOT. Rock armor used to control erosion, protect property, or redirect flows modifies habitat in ways that are as yet unquantified. This letter report documents the methods used and the results obtained from a field data collection program at Washaway Beach that was aimed at studying habitat characteristics and species location and abundance at the groin and dike and comparing it to a nearby control site. This is the first in a proposed series of studies that will document the habitat and occurrence of migrating salmonids through the spring out-migration of juveniles and the fall return of adults.

Authors:
Miller,M. C., Thom,R. M., Williams,G. D., Southard,J. A., Blanton,S. L., O'Rourke,L. K.

Keywords:
research


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McLean,D. I. WA-RD 482.2 Retrofit of Split Bridge Columns - Appendices - Retrofit Design Calculations 2001 TRAC/WSU
Abstract:
Many older bridges in Washington State contain split reinforced concrete columns as common members between adjacent bridge sections. The split detail was incorporated in columns to allow for movements in the bridge due to temperature and shrinkage effects. It is expected that these split columns will perform poorly in the event of a significant earthquake. This study investigated retrofitting measures for improving the seismic performance of existing split columns.Experimental tests were conducted on one-third scale split column specimens which were representative of the split column present in the Spokane Street Overcrossing near Seattle. Various retrofit measures were evalauted. Specimen performance was evaluated on the basis of load capacity, displacement ductility, and hysteretic behavior.Tests on specimens representing as-built conditions revealed vulnerabilities that have previously been observed in the field or are expected to occur during a major earthquake. Poor performance evident in the as-built specimens included crack propagation from the base of the split, lap splice degradation, and shear failure in the split sections.Retrofit design focused on enhancing the column seismic performance while at the same time preserving as much of the gap between the split sections as possible. Procedures were developed for the design of steel jacketing as a retrofit measure for the split columns. Circular jacketing was used for the section below the split and for retrofitting a deficient lap splice. "D" shaped jackets were used for the split sections to provide confinement in flexural hinging regions and to increase shear strength. Tests on specimens retrofitted with the steel jacketing showed significant improvements in performance when compared to that for the as-built specimens.Three compaanies who manufacture composite retrofit systems were invited to participate in this project. Each company was provided with unretrofitted specimens for which they designed and installed their company's retrofit system. While some differences in performance were obtained with the various retrofit systems, all retrofitted specimens showed significant improvements in performance when compared to that for the as-built specimen.

Authors:
McLean,D. I., El-Aaarag,M. H., Rogness,P. D.

Keywords:
research


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Masad,E. WA-RD 530.1 Implementation of High Performance Concrete in Washington State 2001 TRAC/WSU
Abstract:
In this study, the performance of five typical mix designs from four different regions in Washington state is assessed. The performance characteristics that are evaluated include four durability properties: freeze-thaw durability, scaling resistance, abrasion resistance, chloride penetration, and one strength-related property: compressive strength.Determination of the current level of performance of existing concrete mixes is the first step toward fully implementing performance-based specifications. Knowing the level of durability of existing mix designs will give WSDOT a starting point in defining new levels of durability for higher performance mixes. Previously, the selection of appropriate mix designs was based solely on the flexural or compressive strength of the mix. The results of this study enable mix designs to be selected by matching the performance grade with exposure conditions.A map of the state of Washington outlining freeze-thaw zones is presented to indicate exposure conditions. This may be used to match pavement performance grades with actual field conditions. Recommendations based on experimental findings and the literature review are provided for improving the durability of the mixes.

Authors:
Masad,E., James,L.

Keywords:
concrete, performance, freeze-thaw, Scaling, abrasion, permeability, research


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Lewis,L. WA-RD 491.1 Soil Bioengineering for Upland Slope Stabilization 2001 TRAC/National Riparian Service Team, USDA, Fo
Abstract:
The objective of the study was to provide alternatives called soil bioengineering methods for slope and shallow rapid landslide stabilization along different roadside environments. Additional objectives were to educate WSDOT personnel in site selection, soil bioengineering techniques, and construction; to provide soil bioengineering decision-making skills. Three study sites were selected, based upon the following criteria: safety, visibility, accessibility, representation of disparate moisture conditions, climate, and erosion types, illustration of different techniques, availability of additional funding, and WSDOT input. Three different combinations of soil bioengineering techniques were used to stabilize upland slopes on the roadside. Results indicate soil bioengineering is an effective means of upland slope stabilization on erosional slopes and shallow rapid landslides and is practical and economical. Composted biosolids improved soil workability and enhanced the native plant community during the first year.

Authors:
Lewis,L., Salisbury,S. L., Hagen,S., Maurer,M.

Keywords:
benefit, biosolids, branchpacking, brush layering, cordon, cost, cribwall, erosion, erosion control, fascine, landslides, live cribwall, live gully repair, live staking, native plants, research, slope stabilization, soil bioengineering, willow wall


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Kramer,S. L. WA-RD 520.1 Seismic Instrumentation for the Alaskan Way Viaduct 2001 TRAC/UW
Abstract:
The Alaskan Way Viaduct, which runs along the Seattle waterfront, is highly susceptible to damage during earthquakes. Previous studies have shown that extensive soil liquefaction could cause collapse of sections of the Viaduct through a complex mechanism that involves the seismic performance of a neareby seawall. Occurrence of such collapse events would be expected to occur at some time after the initiation of earthquake shaking, thereby providing some period of time in which motorists could potentially be kept from entering the Viaduct. The purpose of this project was to evaluate the feasibility of instrumenting the Viaduct to (a) provide warning of potentiallly unsafe situations, and (b) reduce post-earthquake closure times by speeding the process of evaluating the condition of the Viaduct following earthquake shaking.Because of the numerous and significant sources of uncertainty in the prediction of collapse, a probabilistic approach to the warning system problem was adopted. This procedure accounted for, to the extent possible given available information, uncertainties in ground shaking characteristics, uncertainties in soil properties, uncertainties in seawall behavior, uncertainties in Viaduct foundation behavior, and uncertainties in structural response. The results are expressed in estimated collapse probabilities for various warning system triggering levels. Selection of triggering levels will require balancing the costs and benefits of successful and unsuccessful collapse predictions.Structural analyses of specific sections of the Viaduct were used to develop recommendations for performance monitoring instrumentation. Proposed response levels for inspection and inspection/closure are also presented.

Authors:
Kramer,S. L., Jones,A. L., Eberhard,M. O., Arduino,P.

Keywords:
seismic instrumentation, liquefaction, structural analysis, research


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Ishimaru,J. M. WA-RD 493.1 Central Puget Sound Freeway Network Usage and Performance. 1999 Update, Volume 1 2001 TRAC/UW
Abstract:
This two-volume summary report presents an overview of the level of traveler usage (e.g., how many vehicles use the freeways) and travel performance (e.g., how fast they are traveling, where and how often congestion occurs) on the principal urban freeways in the central Puget Sound area. Volume 1 focuses on descriptive snapshots of 1999 freeway usage and performance, while Volume 2 provides a comparative analysis, looking at trends and variations in the usage and performance of the highway network as a function of different background conditions at selected locations. Data presented in this report were collected by the Washington State Department of Transportation's (WSDOT's) freeway surveillance system.The project that led to this report is intended to meet two separate purposes: 1) to enhance WSDOT's ability to monitor and improve its traffic management efforts on Seattle-area highways, and 2) to provide useful information to the public and decision makers about the status of the freeway system's operational performance. This report is primarily intended to meet the second of these objectives.However, the software developed for this project and many of the graphics presented in this report are directly applicable to the first objective.This report is one of three products resulting from this WSDOT project. In addition to this report, this project produced a set of software tools to assist in freeway data analysis, as well as a technical report describing the evaluation approach, process, and analytical tool set that were developed to analyze freeway usage and performance in the central Puget Sound region. The freeways studied in this project are managed by WSDOT using its FLOW system, a coordinated network of traffic monitoring, measuring, information dissemination, and control devices that operates on urban state and Interstate highways in the central Puget Sound region.

Authors:
Ishimaru,J. M., Nee,J., Hallenbeck,M. E.

Keywords:
Archived Data User Services (ADUS), congestion monitoring, freeway performance, research


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Ishimaru,J. M. WA-RD 493.2 Central Puget Sound Freeway Network Usage and Performance. 1999 Update, Volume 2: Trends 2001 TRAC/UW
Abstract:
This two-volume summary report presents an overview of the level of traveler usage (e.g., how many vehicles use the freeways) and travel performance (e.g., how fast they are traveling, where and how often congestion occurs) on the principal urban freeways in the central Puget Sound area. Volume 1 focuses on descriptive snapshots of 1999 freeway usage and performance, while Volume 2 provides a comparative analysis, looking at trends and variations in the usage and performance of the highway network as a function of different background conditions at selected locations. Data presented in this report were collected by the Washington State Department of Transportation's (WSDOT's) freeway surveillance system.The project that led to this report is intended to meet two separate purposes: 1) to enhance WSDOT's ability to monitor and improve its traffic management efforts on Seattle-area highways, and 2) to provide useful information to the public and decision makers about the status of the freeway system's operational performance. This report is primarily intended to meet the second of these objectives.However, the software developed for this project and many of the graphics presented in this report are directly applicable to the first objective.This report is one of three products resulting from this WSDOT project. In addition to this report, this project produced a set of software tools to assist in freeway data analysis, as well as a technical report describing the evaluation approach, process, and analytical tool set that were developed to analyze freeway usage and performance in the central Puget Sound region. The freeways studied in this project are managed by WSDOT using its FLOW system, a coordinated network of traffic monitoring, measuring, information dissemination, and control devices that operates on urban state and Interstate highways in the central Puget Sound region.

Authors:
Ishimaru,J. M., Nee,J., Hallenbeck,M. E.

Keywords:
Archived Data User Services (ADUS), congestion monitoring, freeway performance, research


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Glad,R. W. WA-RD 515.1 Weave Analysis and Performance: The Washington State Case Study 2001 WSDOT
Abstract:
This research study summarizes current practices for weaving section design and their development from a literature review. Current methodologies and modeling techniques were assessed and then tested with actual characteristics of a major weave section in Washington State. The analysis compared estimated level of service of the techniques for the weaving section and on alternative designs to consider operational improvement opportunities. A safety analysis for collision type and severity was conducted on the accidents through the weaving section, with predicted effects for the alternative designs. The study recommends that weaving sections undergo critical review of traffic projections and roadway characteristics before implementation to avoid operational impacts that can stretch beyond the localized section. Further research on the safety impacts in weaving sections is also recommended.

Authors:
Glad,R. W., Milton,J. C., Olson,D. K.

Keywords:
weaving sections, weaving, ITRAF, FRESIM, research


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Dailey,D. J. WA-RD 527.1 The Use of Uncalibrated Roadside CCTV Cameras to Estimate Mean Traffic Speed 2001 TRAC/UW
Abstract:
In this report, we present a novel approach for estimating traffic speed using a sequence of images from an un-calibrated camera. We assert that exact calibration is not necessary to estimate speed. Instead, to estimate speed we use (1) geometric relationships inherently available in the image, (2) some common sense assumptions that reduce the problem to 1-dimensional geometry, (3) frame differencing to isolate moving edges and track vehicles between frames, and (4) parameters from the distribution of vehicles lengths.

Authors:
Dailey,D. J., Cathey,F. W., Pumrin,S.

Keywords:
video image processing, calibration, camera, speed sensor, vehicle length distribution, transportation, highway, research


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Dailey,D. J. WA-RD 505.1 Smart Trek: A Model Deployment Initiative 2001 TRAC/UW
Abstract:
The SmartTrek project was implemented by a consortium of government agencies, private sector firms, and the University of Washington. The project resulted in a variety of intelligent transportation system (ITS) applications that help traffic management personnel and the traveling public. This report documents the components of the SmartTrek project implemented by the University of Washington. It provides a summary and evaluation of those applications and is a "one-stop shopping" overview of the UW SmartTrek activities.

Authors:
Dailey,D. J.

Keywords:
Intelligent transportation system, advanced traffic management systems, advanced public transportation system, advanced traveler information systems, research


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Bash,J. WA-RD 526.1 Effects of Turbidity and Suspended Solids on Salmonids 2001 TRAC/UW and Center for Streamside Studies, UW
Abstract:
Protection of Washington State's salmonids requires that transportation officials consider the effect of suspended sediments released into streams during transportation projects. Many state and provincial criteria are based on a threshold of exceedance for background levels of turbidity. However, determining natural background levels of turbidity is a difficult endeavor. The inconsistent correlation between turbidity measurements and mass of suspended solids, as well as the difficulty in achieving repeatability using turbidimeters contributes to concerns that turbidity may not be a consistent and reliable tool determining the effects of suspended solids on salmonids. Other factors, such as life stage, time of year, size and angularity of sediment, availability of off-channel and tributary habitat, and composition of sediment may be more telling in determining the effect of sediment on salmonids in Northwestern rivers.For short-term construction projects, operators will need to measure background turbidities on a case-by-case basis to determine if they are exceeding regulations. However, transportation projects may also produce long-term, chronic effects.To adequately protect salmonids during their freshwater residence, TSS data on physiological, behavioral, and habitat effects should be viewed in a layer context, incorporating both the spatial geometry of suitable habitat and the temporal changes associated with life history, year class, and climate variability. Spatial and temporal considerations provide the foundation to decipher legacy effects as well as cumulative and synergistic effects on salmonid protection and recovery.

Authors:
Bash,J., Berman,C., Bolton,S. M.

Keywords:
turbidity, salmonids, suspended solids, research, WSDOT, environmental


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Allen,T. M. WA-RD 528.1 Application of the K 0-Stiffness Method to Reinforced Soil Wall Limit States Design 2001 Washington State Dept. of Transportation
Abstract:
A new design methodology for estimating reinforcement loads in reinforced soil walls, termed the K 0-Stiffness Method, has been developed. This new method has been demonstrated to more accurately estimate reinfocement loads and strains in reinforced soil walls than do current design methodologies. Step-by-step procedures are provided to lead the designer through the reinforced soil wall internal stability design process using this new methodology. These step-by-step design procedures have been developed with a limit states design approach consistent with current design codes (in North America this is termed Load and Resistance Factor Design, or LRFD). Specifically, consideration has been given to strength and serviceability limit states. Load and resistance factors, based on statistical data where feasible, have been developed for use with this method. The results of examples from actual wall case histories were summarized and analyzed to assess how well the new methodology performs relative to current design practice. From this analysis of the design examples, the following was observed: For geosynthetic walls, the K 0-Stiffness Method has the potential to reduce required backfill reinforcement capacity relative to current design methodology by a factor of 1.2 to 3. For steel reinforced soil walls, the reduction in the reinforcement capacity relative to what is required by current design methodology is more modest, on the order of 1.0 to 2.1. Given these findings, use of the K 0-Stiffness Method can result in substantial cost savings, especially for geosynthetic walls, because of reduced reinforcement needs.

Authors:
Allen,T. M., Bathurst,R. J.

Keywords:
reinforcement, walls, loads, strains, creep, design, research, methodology, soil, developed, stability, design process, codes, North, resistance, strength, data, analysis, geosynthetic, steel, cost


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http://www.wsdot.wa.gov/research/reports/fullreports/528.1.pdf http://wsdot.wa.gov/Research/Reports/500/528.1.htm
Singleton,P. H. WA-RD 489.1 I-90 Snoqualmie Pass Wildlife Habitat Linkage Assessment 2000 USDA Forest Service, Pacific Northwest Resear
Abstract:
A multi-scale assessment of wildlife habitat connectivity and barriers to animal movement along 35 miles of Interstate 90 between Snoqualmie Pass and Cle Elum, Washington was conducted from January 1998 to March 2000. This assessment consisted of 5 components: 1) Landscape-scale GIS "least-cost path" modeling to evaluate relative habitat linkage for 4 guilds of wildlife species. 2) GIS analysis of deer and elk road-kill distribution. 3) Automatic camera surveys to evaluate wildlife distribution in the vicinity of the highway. 4) Existing highway structure monitoring to document wildlife use of bridges and culverts. 5) Winter snow tracking surveys to document animal distribution and highway crossing locations. We found that linkage areas identified by GIS habitat linkage modeling for high mobility habitat generalist species and moderate mobility late successional forest species corresponded to areas with high deer and elk road-kill density and frequent highway crossing documented during snow tracking. We identified 4 deer and elk road-kill concentration areas and evaluated the habitat characteristics of these areas. Automatic camera survey detection rates did not differ for camera stations more or less than 1 mile from the highway for most species, but did differ between different highway segments. Bridges and dry drainage culverts were used by 15 mammal taxa. However, medium and large carnivores commonly detected in the vicinity of the highway were not recorded in highway structures. During 250 miles of snow tracking surveys, we recorded 49 highway crossings by coyote, 13 by bobcat, and 5 by raccoon. Highway crossing locations recorded during snow tracking were clustered in distribution. Results of this study were used to identify areas of high landscape permeability for animal movement relative to adjacent areas along the highway corridor.

Authors:
Singleton,P. H., Lehmkuhl,J. F.

Keywords:
wildlife, habitat, corridors, highway barriers, research


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McCrumb,M. WA-RD 496.1 Documentation of the Design and Construction of the New Tacoma Narrows Bridge 2000 TRAC/UW
Abstract:
The newest Tacoma Narrows Bridge will be the largest suspension bridge built in the United States in 40 years. It will also be the first project completed under Washington State's Public-Private Initiatives Act. This study outlines the documentation plan for the design and construction of the new Tacoma Narrows Bridge. The plan includes research task orders associated with the design and construction of the bridge relative to: public relations/educational opportunities, written documentation, and potential research.

Authors:
McCrumb,M., Rutherford,G. S., Mahoney,J. P.

Keywords:
Tacoma Narrows Bridge, research


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McCormack,T. WA-RD 490.1 Polyacrylamide (PAM) Flocculant Dissolution Rate Testing for an Experimental Passive Dosing System 2000 Department of Civil Engineering, Saint Martin
Abstract:
WSDOT is considering the use of Polyacrylamide (PAM) flocculant to reduce stormwater runoff turbidity at highway construction sites. This research project conducted a testing program to determine the dissolution rates of PAM introduced to simulated stormwater flow by using an experimental geotextile "teabag" dosing system.The testing program simulated "teabags" placed in 2 configurations: 1) suspended in a pipe culvert, and 2) placed in a standard catchbasin insert. The flume in the Saint Martin's College School of Engineering Hydraulics Laboratory was used to conduct a full-scale simulation of flow regimes for these 2 configurations.Five types of geotextile fabric, five types of PAM flocculant, and ten configurations of teabag placement were tested. Empirical relationships between the dissolution rate and flow were found by regressing the test results.PAM dissolution rate was found to vary as an inverse power function with flow rate, and directly with the amount of PAM introduced into the flow stream. The type of geotextile fabric and the type of PAM flocculant had only a minor effect on dissolution rate.

Authors:
McCormack,T., House,K.

Keywords:
polyacrylamide (PAM), flocculant, stormwater, turbidity, highway construction, dissolution rate, geotextile, research


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Mahoney,J. P. WA-RD 492.1 A Framework for WSDOT Pavement Research 2000 TRAC/UW
Abstract:
This study documents the development of a pavement research framework for the Washington State Department of Transportation. The framework extends over a six-year period (three biennia) and includes provision for extensive collaboration with other agencies, the private sector, and national funding organizations.

Authors:
Mahoney,J. P., Pietz,M. D., Anderson,K. W., Pierce,L. M.

Keywords:
pavements, research, framework, prioritization


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Mahoney,J. P. WA-RD 487.1 Summary Report On The State Pavement Technology Consortium 2000
Abstract:
This report documents the first year results of a pooled fund study among four states (California, Minnesota, Texas, and Washington State) and describes the structure and objectives. The planned continuation of this collaboration during the next two years is described. The pooled fund project established a working relationship among the four State DOT organizations. Under this agreement, each state allocated funding to allow selected DOT personnel and university researchers to participate in a series of technical meetings. Washington acted as the lead state for this pooled fund project, and produced the minutes and other documentation.Four technical meetings were held between July 1999 and January 2000, one in each of the four participating states. The general format for these meetings included presentations from the host DOT and associated research institutions, followed by specific topics of common interest to the four states. The four states quickly identified topics of mutual interest via this process. To provide the ability to study these topics and those identified in the future, the State DOT research managers agreed to establish a management framework to continue information sharing, to plan funding commitments and assure proper oversight and management of the collaborative studies.described.

Authors:
Mahoney,J. P., Pietz,M. D., Anderson,K. W.

Keywords:
California, Consortium, framework, management, Meeting, Minnesota, objectives, pavement, project, research, Study, technology, Texas, Washington, Washington state


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Mahoney,J. P. WA-RD 498.1 QA Specification Practices 2000
Abstract:
This report provides an initial examination of current quality assurance (QA) and quality control (QC) programs at state highway agencies (SHAs). Of specific interest is the states' use of statistically based specifications.The report overviews questionnaire results from the neighboring SHAs, recently obtained information from the Texas Department of Transportation on mix segregation, and sample results from the Washington State Department of Transportation (WSDOT) QA database.This report is the first of two that examine the current WSDOT QA hot mix specification.

Authors:
Mahoney,J. P., Backus,A. W.

Keywords:
quality assurance, pavement, specifications, survey, research


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Kunkle,R. WA-RD 485.1 Perspectives on Successful Telework Initiatives 2000 WSU Energy Program
Abstract:
The concept of telework was introduced in the 1970's as a way to substitute telecommunications technology for the commute to work (Nilles 1998). Telework promised many environmental, family, employee, and business benefits. With continued advances in information and communication technology, there were great expectations for the growth of telework and its benefits. While the practice of telework has grown, in many respects the high expectations have not been fulfilled.We believe there is value in reexamining telework in order to more proactively take advantage of the beneficial impacts telework might be able to provide to businesses and citizens. The purpose of this research is to develop new perspectives on successful, long-term telework initiatives at organizations in order to better understand how and why initiatives mature, how organizations view telework initiative benefits, and the implications for supporting telework in the future.We conducted research about telework in three areas: telework and the changing nature of work, telework in organizations, and telework and transportation. We used a combination of research methods including secondary research, analysis of successful telework initiatives at three organizations (involving 31 interviews with coordinators, managers and teleworkers), and interviews with key informants.

Authors:
Kunkle,R.

Keywords:
telework, telecommute, organizational change, workforce demographics, flextime, job sharing, research


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Dailey,D. J. WA-RD 463.1 A Self-Describing Data Transfer for ITS Applications 2000 TRAC/UW
Abstract:
A wide variety of remote sensors used in Intelligent Transportation Systems (ITS) applications (loops, probe vehicles, radar, cameras) has created a need for general methods by which data can be shared among agencies and users who own disparate computer systems.In this paper, we present a methodology that demonstrates that it is possible to create, encode, and decode a self-describing data stream using the following:1. existing data description language standards2. parsers to enforce language compliance3. a simple content language that flows out of the data description language4. architecture neutral encoders and decoders based on ASN.1

Authors:
Dailey,D. J., Meyers,D., Pond,L.

Keywords:
self-describing data, SQL, ITS data, ITS architecture, research


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Dailey,D. J. WA-RD 463.2 A Self-Describing Data Transfer Methodology for ITS Applications: Executive Summary 2000 TRAC/UW
Abstract:
A wide variety of remote sensors used in Intelligent Transportation Systems (ITS) applications (loops, probe vehicles, radar, cameras) has created a need for general methods by which data can be shared among agencies and users who own disparate computer systems.In this paper, we present a methodology that demonstrates that it is possible to create, encode, and decode a self-describing data stream using the following:1. existing data description language standards2. parsers to enforce language compliance3. a simple content language that flows out of the data description language4. architecture neutral encoders and decoders based on ASN.1

Authors:
Dailey,D. J., Meyers,D., Pond,L.

Keywords:
self-describing data, SQL, ITS data, ITS architecture, research


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Dailey,D. J. WA-RD 467.1 Busview: An APTS Precursor and JA Deployed Applet 2000 TRAC/UW
Abstract:
The Busview-X project constructed and demonstrated the use of an advanced public transportation system (APTS) to show the viability of providing real-time transit information to transit riders. This project (1) designed an advanced graphical transit information system using data from King County Metro Transit's existing automatic vehicle location (AVL) system and the Puget Sound's regional intelligent transportation systems (ITS) backbone; (2) created a World Wide Web page to launch the application; and (3) demonstrated the system's viability by providing real-time transit coach locations to personal workstations on the University of Washington campus.As a precursor to an APTS for the Puget Sound region, Busview-X was designed to (1) provide real-time coach location information to the test group; (2) enhance King County Metro's existing investment in AVL technology without disrupting existing operations; (3) evaluate AVL accuracy; (4) encourage increased ridership, modal change, and productivity; and (5) be compatible with federal efforts to develop a national ITS architecture. Busview-X was constructed in an open systems model that supported a distributed computing environment. It used the X-windowing system for graphical support. Busview-X was used 2, 490 times over a period of 670 days from November 1995 to September 1997.During the Seattle Smart Trek Model Deployment Initiative, the ideas developed in the campus-based version of Busview-X were used to create a new version, Busview, that could be widely supported on the Internet. Busview was written in the Java programming language so that graphical representation of transit information could be available anywhere on the Internet. The incorporation of a graphical toolkit into Java and its inclusion in widely available WWW browsers allowed the researchers to replace the X-window system with WWW browsers as the graphic user interface.Both versions were well received by users. Comments from Buxview-X were used to improve the design of Busview during the Smart Trek deployment. Refinements to Busview are ongoing.

Authors:
Dailey,D. J., Maclean,S., Pao,I.

Keywords:
automatic vehicle location (AVL), positioning, transit, real-time data, java applet, research


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Dailey,D. J. WA-RD 465.1 Video Image Processing to Create a Speed Sensor 2000
Abstract:
Image processing has been applied to traffic analysis in recent years with different goals. In this report, a new approach is presented for extracting vehicular speed information, given a sequence of real-time traffic images. We extract moving edges and process the resulting edge information to obtain quantitative geometric measurements of vehicles. This differs from existing approaches because we use simple geometric relations obtained directly from the image instead of using reference objects to perform camera calibrations. Our method allows the recovery of the physical descriptions of traffic scenes without explicit camera calibration.In this report, extensive experiments using images from active Transportation Management System (TMS) freeway cameras are reported. The results presented in this report demonstrate the validity of our approach, which requires neither direct camera control nor placement of a calibration object in the environment. We further argue that it is straightforward to extend our method to other related traffic applications.

Authors:
Dailey,D. J., Li,L.

Keywords:
CCTV cameras, moving edge detection, research, speed sensor, video image processing


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Cammermayer,J. W. WA-RD 495.1 Vegetated Stormwater Facility Maintenance 2000 TRAC/UW
Abstract:
This study had three objectives and associated work components: Component I--assess routine highway ditch cleaning alternatives ("Service Levels') for water quality benefits; Component 2--survey biofiltration swales to evaluate conditions promoting water quality benefits; and Component 3--assess restabilization and revegetation options for use after ditch cleaning and for restoring biofiltration swale vegetation.Component 1 tested the water quality effects of three Service Levels in freeway ditches: (1) excavated to original elevation and shape along the upstream three-quarters of the length and then sodded, (2) excavated along the entire length and straw-covered, and (3) excavated along the upstream three-quarters of the length and then strawcovered. Component 2 surveyed representative swales along central Puget Sound area highways for a variety of geometric, hydraulic and vegetative characteristics. Survey data were analyzed to develop maintenance, design, and construction guidelines. In Component 3 vegetation establishment from seed was assessed in replicate plots in a freeway ditch with the assistance of restabilization aids: (1) coconut fiber blanket, (2) straw held in place with stapled jute mat, (3) straw without covering, and (4) polyacrylamide (PAM). Cost-benefit analyses were performed in Components 1 and 3.The overall best Service Level for water quality benefits was excavating the first three quarters and retaining vegetation in the remainder. The ditch treated in this manner was capable of reducing TSS by approximately 40 percent, total phosphorus by about 50 percent, and total and dissolved Cu and Zn each by roughly 20 to 25 percent. It is recommended as the standard procedure when cleaning ditches that discharge to a natural receiving water. Analysis of survey data showed that biofiltration swales with broad side slopes, wide bases, and total storage volumes equivalent to 3 inches of runoff from the impervious drainage area consistently supported good vegetation cover and showed few signs of damage. For assisting grass growth, straw held in place with stapled jute mat had a clear advantage in effectiveness over the alternatives and a slight economy advantage over the coconut mat.

Authors:
Cammermayer,J. W., Horner,R. R., Chechowitz,N.

Keywords:
stormwater facility, maintenance, biofiltration swales, revegetation, water quality, research


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Barr,P. WA-RD 477.1a Live Load Distribution Factors for Washington State SR 18/SR 516 Overcrosssing 2000 TRAC/UW
Abstract:
This report presents an evaluation of live-load distribution factors for a series of three-span, prestressed concrete girder bridges. The response of one bridge, measured during a static live-load test, was used to evaluate the reliability of a finite-element model. Twenty-four variations of this model were then used to evaluate the procedures for computing live-load distribution factors that are embodied in three bridge design codes. The finite-element models were also used to investigate the effects that lifts, intermediate diaphragms, end diaphragms, continuity, skew angle and load type have on distribution factors. For geometries similar to those considered in the development of the American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Specifications (1994), the distribution factors computed with the finite-element models were within 6 percent of the code values. However, for the geometry of the bridge that was tested, the discrepancy was 28 percent. Lifts, end diaphragms, skew angle and load type significantly decreased the distribution factors, while continuity and intermediate diaphragms had the least effect. If the bridge had been designed using the distribution factors calculated with the finite-element model rather than the code values, the required concrete release strength could have been reduced by 6.9 Mpa (1000 psi), or the live load could have been increased by 39 percent.

Authors:
Barr,P., Stanton,J. F., Eberhard,M. O.

Keywords:
live-load distribution, skew, diaphragms, continuity, lifts, research


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Baker,M. J. WA-RD 437.1 Identification And Assessment Of Superior And Inferior Performing WSDOT Pavements 2000
Abstract:
The Washington State Pavement Management System (WSPMS) offers an organized methodology that WSDOT decision makers use to determine optimum strategies for providing and maintaining pavements in a serviceable condition over a given period of time. It also helps improve decision-making efficiency, provide feedback on the consequences of decisions, and ensure the consistency of decisions made at different management levels within WSDOT. Unfortunately, it is not possible, by simply scanning the WSPMS, to pinpoint reasons why pavement sections made of the same general surface materials and subjected to similar traffic and climatic conditions differ in performance. What the WSPMS can do is assist engineers in developing a candidate list of pavement sections with superior and inferior performance. Common characteristics that linkmultiple pavement sections are of particular interest, in part because they may reflect a common practice(e-g., nighttime construction) that leads to superior or inferior performance.This study undertook various extensive analyses and comparisons to help illustrate common attributes of Washington state pavements with superior and inferior performance. The research also reviewed field performance data for Interstate 90 within the 1999 version of the WSPMS. The purpose was to examine all pavement segments on the 480 km of Interstate 90 within Washington state.Reducing variability will allow WSDOT to produce more consistent pavement performance and will allow increasingly effective planning and forecasting. An almost certain byproduct of this increased planning effectiveness will be a more efficient allocation of available funding.

Authors:
Baker,M. J., Mahoney,J. P.

Keywords:
Assessment, condition, construction, data, effectiveness, forecasting, management, management system, materials, methodology, pavement, pavement management, pavement performance, pavement section, pavements, performance, planning, research, superior inferior, System, traffic, Washington, Washington state, WSDOT


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Simenstad,C. A. WA-RD 472.1 Impacts of Ferry Terminal on Juvenile Salmon Migrating Along Puget Sound Shorelines: Phase I--Synthesis of State of Know... 1999
Abstract:
This project is assessing whether ferry terminals affect juvenile salmon migrating along estuarine and nearshore marine environments and, if so, how design of and modifications to both ferry terminals and operations can mitigate those impacts. This project has three phases. This report summarizes results from Phase I (status of knowledge, initial terminal surveys) and implications for Phase II and III research.We addressed three issues about overwater structures impacts on juvenile salmon: (1) alteration in migratory behavior, (2) reduction in prey production and availability, and (3) increased predation. An assessment of over 60 direct sources of information found evidence that juvenile salmon react to shadows and other artifacts in the shoreline environment created by shoreline structures. While changes in light have been shown to affect salmon migration behavior and thus potentially place them at increased mortality risk, we found no quantitative information on the significance of these behavioral responses to juvenile salmon survival. Juvenile salmon also encounter limited prey resources under shoreline structures when important habitats such as eelgrass (Zostera marina) are disturbed. Modifications to light, temperature, salinity, nutrient levels, and wave action beneath an overwater structure influence the rate of photosynthesis, plant distribution, and survival of specific plant species that directly or indirectly support prey resource composition and production. Despite considerable speculation about increased predation around docks, quantitative evidence for significant increases in predation on salmon associated with docks is lacking.We also conducted short-term underwater diving and video surveys at five ferry terminals (Clinton, Kingston, Port Townsend, Seattle, Vashon) to gather preliminary information on the relationships among variations in over-water structures, fish occurrence and relative abundance, light conditions, biological communities, and potential predators. Juvenile salmon were observed migrating under several structures.Existing information indicates that the effects of shoreline structures on migrating juvenile salmon may vary, depending on the design and orientation of the shoreline structure, extent of alteration of the underwater light field, and presence of artificial light. However, our understanding of the significance of short-term delays in the salmons' migration and cumulative or synergistic effects is insufficient to provide the quantitative relationships that would be necessary as the basis for developing retrofitting or design modifications. Field studies are recommended.

Authors:
Simenstad,C. A., Nightingale,B., Thom,R. M., Shreffler,D. K.

Keywords:
salmon migration, shoreline structure, fish habitat impacts, underwater light, predation, research


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Shreffler,D. K. WA-RD 480.1 Impacts of Ferry Terminals on Juvenile Salmon Migrating Along Puget Sound Shorelines: Phase II--Field Studies at Port To... 1999 Battelle Marine Sciences Laboratory
Abstract:
The University of Washington (UW) and Battelle Marine Sciences Laboratorv (MSL) are jointly conducting a multiyear, three-phased research program to determine whether ferry terminals affect migrating juvenile salmon, and if so, how future design of ferry terminals and modifications to both terminals and operations can mitigate those impacts. Phase I resulted in a report synthesizing the technical knowledge regarding the potential effects of shoreline structures on migrating juvenile salmon. This report summarizes our results from Phase II pilot field studies at the Port Townsend ferry terminal in spring 1999 and provides recommendations for proposed onsite tests of the effects of a range of different WSDOT ferry terminals and vessel activity patterns in Phase III (spring-winter 2000). The overall goal of Phase II was to perform pilot field experiments with releases of hatchery chum and chinook fry to test whether the Port Townsend terminal stops or delays the natural migration of juvenile salmon. Monitoring methods included diving surveys, beach seining surveys, single-beam and split-bearn hydroacoustics, remote underwater video, and in situ light sensors.River otters directly and indirectly resulted in mortalities to approximately 29,000 of the 30,000 chinook fry and 39,700 of the 40,000 chum frv that we were holding in net pens for experiments. We released the remaining fish 30 in from the southern edge of the Port Townsend ferry terminal on June 11, 1999. On the basis of this one-time experiment, we found no evidence that the Port Townsend ferry terminal was a barrier to the migration of the 1000 chinook that we released. We havc no data or observations for the 300 chum fry after their release. The released chinook fry stayed in a school and did not disperse upon encountering the Port Townsend ferry terminal. The chinook fry did not divert their migratory route into deeper water or around the offshore perimeter of the terminal. Surface observations, underwater video, and the single-beam and split-beam hydroacoustics confirmed that the chinook migrated from the release point directly to the shadow line underneath the terminal. The chinook fry stopped at the shadow line and then displayed a consistent behavior of swimming underneath the terminal. The chinook fry stopped at the shadow line and then displayed a consistent behavior of swimming from the darkness of the shadow line and near the bottom into the light to feed at the surface. As the sunset and the shadow line progressed further underneath the terminal, the chinook school appeared to follow the shadow line under the terminal and, we assume, out the other side. However, we caution that it is neither prudent nor valid to conclude that ferry terminals either do or do not have an effect on juvenile salmon migration, on the basis of these preliminary findings. The loss of the majority of our fish for experiments, the harddrive crash on the navigation computer, and the malfunctioning of some of the singlebeam transducers compromised this study. The fundamental question of whether ferry terminals are a "barrier ' to juvenile salmon migration remains unanswered.

Authors:
Shreffler,D. K., Moursund,R. A.

Keywords:
salmon migration, over-water structure, hydroacoustics, underwater video, light sensors, chum salmon, chinook salmon, research


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Muench,S. T. WA-RD 437.2 Evaluation of the TransTech Pavement Quality Indicator 1999
Abstract:
Recently, WSDOT acquired a non-nuclear, non-destructive, density measuring device manufactured by TransTech called a Pavement Quality Indicator (PQI). TransTech's PQI measures pavement density indirectly by measuring its dielectric constant. A non-nuclear gauge is advantageousbecause it contains no radioactive source and is therefore not subject to radiological controls, and it can obtain readings in about 5 seconds versus I to 4 minutes with a nuclear gauge. Currently, TransTech is collecting data from different agencies to determine the PQI's suitability for measuring asphalt pavement density. This brief study presents density measurements from TransTech's PQI and compares them with nuclear density gauge and core density measurements from three WSDOT 1998 paving projects. This evaluation was a secondary study to WSDOT's 1998 study Asphalt Concrete Construction-Related Temperature Differentials in Washington State; therefore this study's experimental design was based entirely on the Temperature Differential study requirements, which resulted in non-random samples and multiple populations within the same sample groups. Despite these problems, results indicate that, when averaged, PQI readings compare favorably with both nuclear measurements and core measurements.

Authors:
Muench,S. T., Mahoney,J. P., Cawley,B.

Keywords:
asphalt concrete, density, pavement quality indicator, nuclear gauge, core densities, research

McCormack,E. D. WA-RD 460.1 The Contribution of ITS to Rural Safety: A Look at Crashes in Washington State 1999 TRAC/UW
Abstract:
Increasingly, transportation professionals are using technology, known as Intelligent Transportation Systems (ITS), to address transportation problems. This paper investigates the potential applications of ITS to safety issues on rural roadways in Washington. The most frequent type of rural crashes and their casual factors are identified from the state's Collision Report Form. The ability of ITS applications to reduce these types of crashes is then discussed.In Washington State, the factors that contribute most to rural crashes is human behavior. Some ITS applications, such as speed warning systems, may be good solutions at known hazardous locations. However, most human behavioral issues, such as inattention or poor driver judgment, cannot be directly addressed by ITS application that are currently available.In Washington, crashes due to some aspect of the roadside environment involved about one third of the vehicles. ITS offer a viable alternative to traditional engineering solutions for a number of these types of crashes by informing drivers about roadside hazards. ITS weather systems and traveler information systems in general, can indirectly improve rural safety by providing information about travel and roadway conditions. Rural intersections, work zones, and railroad crossings are other potentially hazardous areas where ITS may be useful.The final factor that contributes to a small percentage of rural crashes is the vehicle and- ITS applications may help indirectly by making trucks more compliant with safety laws and by improving the efficiency of safety inspections.ITS emergency notification systems also offer some safety benefits by mitigating some of the consequences of rural crashes.For the WSDOT, a handful of ITS safety applications have been well enough tested that they can be aggressively used as tools to reduce rural crashes. However, many more ITS safety applications, although promising, still need to be fully documented and would be best applied in this state as a demonstration of future potential. Most of these applications would warn drivers about road and roadside hazards. The greatest benefit from ITS for rural safety may come from future applications that will address rural crashes caused by human behavior. These applications will evolve from a number of the large federal research projects that are under way and are still a number of years away from providing benefits on a wide scale. Given their potential impact on rural safety, WSDOT should monitor these projects closely.

Authors:
McCormack,E. D., Legg,B.

Keywords:
rural accidents, rural travel, rural safety, ITS, Washington state, research


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McCormack,E. D. WA-RD 460.2 Technology and Safety on Urban Roadways: The Role of ITS for WSDOT 1999
Abstract:
This report examines the relationship between Intelligent Transportation Systems (ITS) and safety from an urban perspective.Existing urban ITS systems are either system-level or site-level applications. System-level ITS, such as freeway management systems or traffic signal networks, address safety concerns only indirectly. These systems are designed to improve traffic flows and thus indirectly reduce collisions caused by congestion. Other system-level ITS used to increase the efficiency of transit, commercial vehicle, and emergency service operations also benefit safety indirectly. Site-level ITS applications, such as railroad/highway crossing warnings or work zone systems, are installed to directly address safety concerns. However, these applications are limited to specific locations identified as hazardous.Most urban crashes in Washington involve multiple vehicle collisions caused by driver error at locations that have not been identified as hazardous. Future ITS systems known collision avoidance systems (CAS) hold considerable promise for urban roadway safety because these in-vehicle devices will inform drivers of judgment errors and can do so at many locations along an urban roadway system.A handful of ITS applications are so well tested that they can be aggressively pursued by WSDOT as tools to reduce urban crashes. Most of these applications include the various systems, such a ramp meters and incident detection, used for freeway management. Other ITS safety applications, while promising, still need to be fully documented and are best used as demonstration applications. Most of these applications involve sensor technology used to warn drivers about road and roadside hazards at specific sites. The greatest safety benefit from ITS may come from in-vehicle collision warning systems. These applications should evolve from a number of large federal research projects and private industry initiatives that are under way. Given their potential impact on safety, WSDOT should monitor applications of these projects.

Authors:
McCormack,E. D., Legg,B.

Keywords:
roadway safety, ITS, urban, Washington state, research


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Lee,J. WA-RD 475.1 Analysis of Roadside Accident Frequency and Severity and Roadside Safety Management 1999
Abstract:
In Washington State, priority programming for evaluating accident prevention and mitigation (safety improvement) involves analysis of roadside features, but the effects that such features. have on the frequency and severity of accidents is not well understood. This study investigated the relationships among roadway geometry, roadside characteristics, and run-off-roadway accident frequency and severity to provide a basis for identifying cost-effective ways to improve highway designs that will reduce the probability of vehicles leaving the roadway and the severity of accidents when they do.To better understand the effects of roadside features on accident frequency and severity, the researchers surveyed other states' priority programming practices. The survey showed that proactive approaches, in general, are in their infancy, and none of them adequately accounts for the effects of roadside features on accidents.To quantify the effects of roadside features on accident frequency and severity, the researchers gathered data from the northbound direction of State Route 3 in Washington State. For accident frequency analysis, negative binomial and zero-inflated negative binomial models of monthly accident frequency were estimated. The findings showed both significant differences and similarities in the factors that affect urban and rural accident frequencies. The results indicated that run-off-roadway accident frequencies can be significantly reduced by increasing lane and shoulder widths; widening medians; expanding approaches to bridges; shielding, relocating, and removing roadside hazardous objects; and flattening side slopes and medians. The statistical analysis also provided an estimate of the magnitude of the influence of these factors.The effects of roadside features on run-off-roadway accident severity were studied with a nested logit model. Roadside features that were found to significantly affect the severity of run-off-roadway accidents included bridges, cut-type slopes, ditches, culverts, fences, tree groups, sign supports, utility poles, isolated trees, and guardrails. As was the case for the frequency analysis, elasticity estimates allowed quantification of the effects of roadside features on accident severity.

Authors:
Lee,J., Mannering,F. L.

Keywords:
accident analysis, roadside features, accident frequency, accident severity, highway safety, research


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Leahy,R. B. WA-RD 486.1 Superpave--Washington DOT's Assessment and Status 1999 Civil Construction and Environmental Engineer
Abstract:
Funded by the 1987 Intermodal Surface Transportation Efficiency Act, the Strategic Highway Research Program (SHRP), was a five year, $150 million research program to improve the performance of the nation's roads by addressing four key areas: concrete and structures; highway safety and maintenance; asphalt; and long-term pavement performance. Nearly one-third of the $150 million was allocated for the study of asphalt, specifically to develop performance based specifications that would relate material properties of the binder and the mix to field performance. Superpave (Superior PERforming asphalt PAVEments) encompasses the products of the SHRP asphalt research program and consists of three interrelated elements: an asphalt binder specification with supporting tests; a mix design and analysis system with supporting tests; and performance prediction models. This report is a compilation and synthesis of Washington DOT's (WSDOT) experience with selected components and concepts of the SHRP/Superpave technology to include the following: performance graded (PG) binder usage and specification validation; gyratory mix design; the Superpave Shear Test (SST); and field performance of the Superpave mixes.Binders typically specified by WSDOT (AR400OW and PBAs -2, -5, -6. -6GR) were classified in terms of five Superpave performance grades: PG 58-22; 64-22; 64-28; 64-34; and 70-28. Although data from 171 weather stations suggest that as many as 6 low- and 5 high-temperature grades could be specified, binder availability and regional pavement distress were used to develop guidelines for statewide PG usage. Three binders were recommended for use in the western, northeastern and southeastern regions of the state as follows: PG 58-22; PG 58-34; and PG 64-28, respectively. Validation of the binder specification with respect to low temperature cracking was accomplished using binder and field performance data from 28 projects. The results were very encouraging: the original SHRP algorithm for binder selection correctly "predicted" field performance in 22 of 28 cases, whereas the LTPP algorithm for binder selection correctly "predicted" field performance in 26 of 28 cases.Additionally, a laboratory experiment using the Superpave Shear Test (SST) apparatus was undertaken to test the effectiveness of binder "bumping," i.e., increasing the high temperature grade because of exceptionally high traffic volume and/or slow or standing traffic. The data clearly indicate that the SST is an effective tool for discriminating between binders and that 'bumping" may be effective in reducing pavement rutting. Permanent shear strain for specimens made with a PB 70-xx binder was only 25 to 33% of the shear strain for specimens made with a PG 58-xx binder.As originally configured, the Superpave mix design matrix included seven traffic levels and four temperature regimes for 28 possible compaction levels. Recognizing that the 28 compaction levels made for a somewhat unwieldy system, WSDOT attempted to reduce the number of compaction levels by conducting a series of mix designs at each compaction level. The results of the limited experiment suggest that it might be possible to limit the number of compaction levels required for mix design. Research by Brown et. al. (NCHRP 99) tends to confirm this as they have suggested reducing the number of compaction levels and provided more definitive guidance with respect to each level.Since 1993 WSDOT has place 44 projects which include some component of the Superp ave technology. For 17 of these projects parallel Hveem and Superpave mix designs were conducted. In 13 of the 17 cases, the Superpave design asphalt content was equal to or greater than the Hveem design asphalt content, though the difference was usually no more than 0.2%. A fundamental difference between Hveem and Superpave mix design methods is the compaction device. Data from these field projects indicate that the current kneading and gyratory compaction protocols (at least for 109 gyrations) yield similar air void contents.As noted previously, Washington DOT has placed 44 projects which involve some component of the Superpave technology. For 18 of the projects a conventional Hveem mix design was conducted using a PG binder (Hveem-PG). The remaining 26 projects were truly Superpave, i.e., the materials selection and mix design were established in accordance with the Asphalt Institute's SP2, Superpave Level 1 Mix Design. According to WSDOT practice the following numerical indices trigger maintenance: Pavement Structural Condition (PSC) 10 mm; or International Roughness Index (IRI) > 500 cnVkm. Although relatively "young", the 44 projects are performing quite well. The average values of rutting, PSC, and IRI (4, 91, and 121, respectively) are all well below the "trigger" values. With respect to rutting and PSC, the performance of Hveem-PG and Superpave projects is virtually identical. However, the ride quality of the Superpave projects is a bit rougher than the Hveem-PG binder projects: IRI of 134 for the former and 103 for the latter. The higher values of IRI measured on the Superpave projects may be the result of the typically coarser aggregate gradation or differences in construction techniques.WSDOT's Superpave experience has not been without challenges. Still, its overall experience has been very encouraging. Experimentation with the revised compaction matrix, continued use of the SST, field validation of the "bumping" experiment, and long-term monitoring of field performance will provide the necessary data to allow WSDOTs critical assessment of Superpave's technical merit and economic viability.

Authors:
Leahy,R. B., Briggs,R. N.

Keywords:
SHRP, Superpave, asphalt, intermodal, transportation, transportation efficiency, highway, research, program, performance, concrete, structures, highway safety, safety, maintenance, pavement, specifications, specification, asphalt pavement, pavements, tests, design, analysis, prediction, models, Washington, WSDOT, data, temperature, cracking, LTPP, traffic, volume, compaction, materials, condition, international roughness index, roughness, index, ride quality, quality, aggregate, construction, ITS, monitoring


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Ishimaru,J. M. WA-RD 466.1 Central Puget Sound Freeway Network Usage and Performance 1999 TRAC/UW
Abstract:
This summary report presents an overview of the level of traveler usage (e.g., how many vehicles use the freeways) and travel performance (e.g., how fast they are traveling, where and how often congestion occurs) on the principal urban freeways in the central Puget Sound area for 1997. Data presented in this report were collected by the Washington State Department of Transportation's (WSDOT's) freeway surveillance system.The project that led to this report is intended to meet two separate purposes: 1) to enhance WSDOT's ability to monitor and improve its traffic management efforts on Seattle-area highways, and 2) to provide useful information to the public and decision makers about the status of the freeway system's operational performance. This report is primarily intended to meet the second of these objectives. However, the software developed for this project and any of the graphics presented in this report are directly applicable to the first objective.This report is one of three products resulting from this WSDOT project. In addition to this report, this project produced a set of software tools to assist in freeway data analysis, as well as a technical report describing the evaluation approach, process and analytical tool set that were developed to analyze freeway usage and performance in the central Puget Sound region. The freeways studied in this project are managed by WSDOT using its FLOW system, a coordinated network of traffic monitoring, measuring, information dissemination, and control devices that operates on urban state and Interstate highways in the central Puget Sound region.

Authors:
Ishimaru,J. M., Hallenbeck,M. E.

Keywords:
Archived Data User Services (ADUS), congestion monitoring, freeway performance, research


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