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Hallenbeck, M.E. Analysis of Changing Transit Travel Behavior as a Result of the Opening of the U-District, Roosevelt, and Northgate Link... 2024 TRAC/UW
Abstract:
On October 2, 2021, Sound Transit of the Puget Sound region of Washington state started Link light rail service to three new stations on the 1 Line . These stations serve the University District, Roosevelt, and Northgate in Seattle. In coordination with the station openings, Sound Transit, King County Metro, and Community Transit of Snohomish County restructured many of their routes that had previously provided express service to downtown Seattle and the University District. This report examines the changes in travel behavior that occurred as a result of those change in transit service. Comparisons are made primarily between September / October 2019 (the last pre-Covid-19 year) and September / October 2021.

Authors:
Hallenbeck, M.E., Hager, G., Avery, R.

Keywords:
Transit service, light rail, travel behavior, planning, transfer


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Hallenbeck. M.E. Operations Performance Management Primer: From Performance Measures to Performance Management 2024 FHWA
Abstract:
The purpose of this Primer is to orient transportation practitioners to the principles and practices of Operations Performance Measures and Management (OPMM). OPMM aims to support continuous improvement in the practice of Transportation Systems Management and Operations (TSMO), a set of strategies that focus on operational strategies that improve the transportation system. Simply put, OPMM includes traditional operations performance measurement practices while incorporating the Transportation Performance Management (TPM) principles for TSMO programs. OPMM is a strategic and data-driven approach to making investment and policy decisions to achieve operations goals.

Authors:
Hallenbeck. M.E., Margiotta, R.A., Lindsey, C., Motamed, M.

Keywords:
Operations, performance measures, performance management, capability maturity, transportation systems management and operations, strategic, data, data-driven, policy, investment


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Gordon, B. WA-RD 938.1 Leading Indicators of Transportation Equity: Equity in Planning 2024 TRAC/UW
Abstract:
This report was commissioned as part of the Washington State Department of Transportation’s (WSDOT) Equity in Planning (EiP) project. It presents knowledge drawn from transportation equity academic literature, practice-oriented literature, community engagement, geospatial (GIS) analysis, and a survey of planning professionals. The project aims to comply with Washington state’s Environmental Justice (EJ) legislation, SB 5141, known as the HEAL (Healthy Environment for All) Act. The HEAL Act sets the goal that 40 percent of major state expenditures be directed toward overburdened communities and vulnerable populations. It mandates that EJ analyses be performed by seven state agencies, including WSDOT. This report identifies leading indicators of transportation equity that WSDOT can incorporate into its planning processes for long-range, regional, and corridor planning initiatives.

Authors:
Gordon, B., Lewis. E.

Keywords:
Equity, leading indicators, planning, community engagement, geospatial analysis


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Wang, Y. 2024 Washington Transportation Camp Program Report 2024 TRAC/UW
Abstract:
The primary objective of the Washington Transportation Camp program is to promote an increased number of students pursuing advanced degrees and careers in STEM-related fields associated with transportation. This mission emphasizes a particular commitment to broadening the participation of women and minority groups within these fields. Ultimately, the program aims to contribute to the development of a skilled and diverse STEM workforce. The 2024 Washington Summer High School Transportation Camp was designed as a comprehensive, six-day, five-night residential program. It took place at two prestigious institutions: Washington State University (WSU) in Pullman from July 21st to 26th, and the University of Washington (UW) in Seattle from August 4th to 9th. The 2024 program was generously sponsored by PacTrans and WSDOT and was offered free of charge to all participating students. Both camps welcomed 36 students, with 25 at the UW and 11 at WSU. The success of both camps was underscored by overwhelmingly positive feedback from students and parents.

Authors:
Wang, Y., Manawadu, A., Wu, L., Wen, H.

Keywords:
STEM, education, workforce development, summer camp, high school


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Nazari, M.H. CR 18-06 Standard Method of Test for Mechanical Rocker Ice Melting 2024 TRAC/WSU
Abstract:
Winter road maintenance provides significant safety and economic benefits during adverse winter weather conditions. Chemicals are commonly used prior, during and after storms to provide better road conditions through a variety of mechanisms. The solid deicer most used by State departments of transportation (DOTs) is sodium chloride (NaCl), but the use of liquids has been increasing steadily for over 20 years because of their many benefits and advantages. Uses of liquid deicers include liquid-only application for anti-icing, frost prevention, treating thin ice, etc. and as a pre-wetting agent to reduce bounce/scatter of solid salt and speed initial melting/penetration. While NaCl is the most common chemical product used by state and local transportation agencies in solid and liquid (brine) form, there are many additives, alternatives and performance-enhancing products and blends available. As such, a standardized laboratory test that can realistically and robustly assess the performance of deicers is needed to allow DOTs to make data-driven procurement decisions. This research conducted a round robin test to examine the effect of rotational speed, test duration, tilt angle, operating laboratory on IMC of ten liquid deicers measured by the Mechanical Rocker Ice Melting Test.

Authors:
Nazari, M.H., Jamal, M., Green, D., Gonzalez, J., Beaurivage, S., Smith, H., Mislang, J., Potapova, A., Akin, M., Shi, X.

Keywords:
Winter road maintenance, deicer, ice melting capacity, SHRP test, Mechanical Rocker Ice Melting Test


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Shen, Q. 2022 Seattle Commute Survey 2023 Commute Seattle
Abstract:
The Washington State Commute Trip Reduction law requires worksites with 100 or more full-time employees who begin their shift between 6:00 and 9:00 a.m. on weekdays to conduct a biannual commute survey. Commute Seattle has led this survey work since 2010, and in partnership with the Downtown Transportation Alliance, it has used the results to measure progress toward the city\\\'s mobility goals. In 2022, Commute Seattle joined the University of Washington’s Mobility Innovation Center and the Department of Urban Design and Planning to improve and expand upon the survey and evaluate current transportation systems. The results give transportation planners a clearer picture of travel trends in relation to demographic groups, employment types, and housing.

Authors:
Shen, Q., Ashour, L., Moudon, A.V., Treece, B.,

Keywords:
Commute, CTR, Mobility, Telework, Seattle


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Shen, Q. WA-RD 925.1 Developing a Multi-Criteria Prioritization Tool to Identify Promising Locations for Transit-Oriented Developments on WSD... 2023 TRAC/UW
Abstract:
Public agencies can take a leading role in supporting transit-oriented development (TOD) by making land available to developers (selling or leasing land, potentially below market prices). With existing access to transit systems and often large land areas, park and rides that are publicly owned can be leveraged to support TOD uses, such as affordable housing, office space, small businesses, and mixed-use buildings. To effectively support TOD planning, this research developed a multi-criteria prioritization tool to identify the most promising locations for TOD and tested it at three park and ride sites owned by the Washington State Department of Transportation. The tool was developed through the Delphi process, which is an effective and inexpensive approach for evaluating relevant indicators by synthesizing the opinions of experts from various backgrounds. Five categories with a total of 14 TOD indicators, including transit supportive land-use zoning, job accessibility, land price, land-use mix, and household income, were selected as measures of TOD suitability. The importance of these indicators varied with three different TOD scenarios: (1) emphasis on affordable housing, (2) emphasis on market-rate housing, and (3) emphasis on mixed-use development. Using the calculated suitability scores, this tool can prioritize potential TOD sites for further review.

Authors:
Shen, Q., Acolin, A., Moudon, A.V., Cai, M.

Keywords:
TOD, Delphi Method, multi-criteria planning tool, multi-sources geospatial data, publicly owned land


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Simonen, K. WA-RD 926.1 Greenhouse Gas Emissions Inventory from Construction of WSDOT Roadways 2023 TRAC/UW
Abstract:
Recent emphasis on actions to reduce large-scale greenhouse gas (GHG) emissions has pushed most state departments of transportation (DOTs) to develop carbon accounting practices compatible with their current standard data collection and storage practices. In particular, with the recently passed Buy Clean Acts in California, Colorado, and Oregon and the recently proposed Buy Clean and Buy Fair Washington Act, common construction materials such as cement concrete, steel, and asphalt are now under special attention. Once accurate and reliable accounting of GHG emissions has been established, strategies can be formed that will help mitigate the adverse environmental impacts of materials that state DOTs utilize. This project, in collaboration with WSDOT, is an attempt to perform a lifecycle assessment (LCA) on some of its agency-wide operations that emit GHGs. To date, WSDOT has not conducted comprehensive research on the embodied carbon within its construction material usage (i.e., an upstream Scope 3 emissions inventory), with most previous carbon accounting practices being focused on Scope 1 and Scope 2 emissions (i.e., the carbon footprint of direct and indirect energy usage). Although several strategies are now in place to cut Scope 1 and 2 emissions, such as the use of alternative and renewable energy sources, strategies to reduce Scope 3 emissions have neither been fully recognized nor quantified. Therefore, this project used several data sources from WSDOT in conjunction with lifecycle emission factor data to estimate GHG emissions from the materials used to build and maintain roadways under WSDOT’s jurisdiction. We found that upstream Scope 3 emissions for WSDOT as an agency are a big contributor to its overall carbon footprint by a five-year average of 310,000 metric tons of CO2 eq. This project further suggested carbon reduction targets for WSDOT and provided recommendations to achieve GHG reduction targets of 50 percent below the 2020 baseline in 2030 and 90 percent below the 2020 baseline in 2050 through decarbonization scenarios.

Authors:
Simonen, K., Ashtiani, M., Lewis, M., Huang, M.

Keywords:
Embodied carbon, greenhouse gas emissions, lifecycle assessment, hot mix asphalt, cement concrete


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Wang, Y. WA-RD 904.1 Real-Time Parking Information Integration, Visualization, and Prediction 2023 TRAC/UW
Abstract:
The trucking industry plays a critical role in freight transportation in the United States. One major problem commonly recognized across the country is inadequate truck parking supply because existing truck parking facilities are struggling to meet the demand of increasing numbers of trucks on the road. Lack of parking spaces and real-time parking availability information greatly exacerbates the uncertainty of trips and often results in illegal parking and/or overtime driving. In this project, WSDOT worked with the research team at the University of Washington (UW) Smart Transportation Applications and Research Laboratory (STAR Lab) to conduct a truck parking pilot study on advanced truck parking management systems. Specifically, this project developed a comprehensive solution in which a parking detection system collects and processes robust, real-time parking data, a predication algorithm estimates future parking availability information, and an online parking availability information platform accessible from smart phones and other personal electronic devices provides real-time and predicted parking information. Empowered by artificial intelligence and a deep learning prediction algorithm, the pilot Truck Parking Information Management System (TPIMS) achieved an error rate of less than 12 percent in predicting parking availability from 10 minutes to four hours ahead. Both the real-time and multi-timescale prediction occupancy information is successfully disseminated via a customized website and user applications in real time. This real-time truck facility monitoring information and truck parking availability prediction will provide information to truck drivers for trip routing and scheduling arrangements.

Authors:
Wang, Y., Yang, H., Zhuang, Y., Sun, W.

Keywords:
Truck parking, information management system, parking prediction, parking demand, parking facilities,


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Shrestha, K. WA-RD 932.1 WSDOT Maintenance Performance Measure Algorithms 2023 TRAC/WSU
Abstract:
This research project focused on deteriorating roadway asset conditions, emphasizing the challenges encountered by the roadway maintenance division of the Washington State Department of Transportation (WSDOT). The project goal was to develop algorithms for prediction models that can forecast the levels of service (LOS) performance conditions of six important highway assets: culverts, barriers, traffic signal systems, ditches, slopes, and shoulders. These algorithms are based on a data-driven approach. The algorithms provide a step-by-step process for developing prediction models. The models can be used to forecast LOS performance conditions and trends under various funding levels, allowing them to set performance targets that align with available funds and asset maintenance priorities, potentially preventing expensive reactive maintenance. Data collection included direct collection from WSDOT and two-phase questionnaires to document factors affecting LOS performance conditions. Statistical analyses such as the Relative Importance Index (RII), Kolmogorov-Smirnov and Shapiro-Wilk normality tests, and Mann-Whitney U tests were employed to determine critical factors for each of the six assets. The project identified the top five highly ranked factors for each asset, which were utilized during model development. Prediction models serve as a tool for forecasting asset conditions, calculating the base funds required for each asset, and optimizing resource allocation. Through the project outcomes, states will be able to improve asset management decision-making, resulting in safer and more environmentally friendly roads.

Authors:
Shrestha, K.

Keywords:
Culvert maintenance, barrier maintenance, traffic signal systems, ditches, slope repair, Washington state


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MacKenzie, D. WA-RD 930.1 Analytic Tools for Locating, Sizing, and Evaluating Electric Vehicle Charging Stations 2023 TRAC/UW
Abstract:
The Washington State Legislature directed the Department of Transportation to develop analytic tools “to enable coordinated, effective, efficient, and timely deployment of charging and refueling infrastructure necessary to support statewide and local transportation electrification efforts that result in emissions reductions” consistent with state goals. This report reviews the available analytic tools for planning electric vehicle (EV) charging infrastructure and makes recommendations on how to meet legislative requirements for mapping and forecasting zero-emission vehicles and recharging equipment. The report presents an approach for generating a ten-year forecast of EV adoption at the census tract level and presents the results of that method. The report also describes an approach to simulating EV charging at public stations that estimates the plug count and power levels needed to meet charging demand with low wait times and the corresponding electric energy and capacity required to serve the charging demand. The report concludes with opportunities for additional research and development to create practical analytic tools that would assist planners and policymakers in making decisions about EV charging investments.

Authors:
MacKenzie, D., Coenen, S., Aemmer, Z., Malarkey, D.

Keywords:
Electric vehicle charging, analytic tools, forecasting, simulation models, queueing models, electric energy, power, capacity


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Haselkorn, M.E. Model Deployment of the Virtual Coordination Center for Multimodal Integrated Corridor Management 2023 FHWA
Abstract:
The Virtual Coordination Center (VCC) is a digital collaborative environment for integrated multimodal corridor management. Under the Federal Highway Administration project “Model Deployment of the Virtual Coordination Center for Multimodal Integrated Corridor Management,” an operational community of state, city, and county agencies including law enforcement, transit, and transportation departments developed, deployed, and evaluated a VCC for interagency management of the Seattle urban corridor. Led by the Washington State Department of Transportation (WSDOT) and the University of Washington, this project produced an innovative collaborative environment that now supports Seattle Fire (SFD), Police (SPD), and Transportation (SDOT), King County Metro Transit, Sound Transit, Washington State Patrol (WSP), and WSDOT in their interagency management of incidents that affect the regional transportation system. The VCC provides daily operational value and is designed to support the management of high-impact situations that put unusual stress on the Seattle-area transportation corridor. The VCC supports increased shared situational awareness, enhanced incident and congestion management, and coordinated population movement.

Authors:
Haselkorn, M.E., Phelps, T.

Keywords:
Virtual coordination, incident management, multimodal, congestion management,


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Motter, C.J. Data-Driven Assessment of Post-Earthquake Bridge Functionality and Regional Mobility 2023 PacTrans
Abstract:
The seismic performance of bridges is essential to post-earthquake mobility, as bridges are relied upon to carry goods and people into and out of urban centers after natural disasters. A 2019 Department of Homeland Security (DHS) report assessing the regional resiliency of Western Washington state to a Cascadia Subduction Zone (CSZ) earthquake predicted widespread and high levels of bridge damage. A primary objective of this study was to create an improved prediction of non-functional, partially functional, and functional bridges that will assist in post-earthquake emergency planning. The Washington State Department of Transportation (WSDOT) bridge database was expanded to include site class, properties of abutments and foundations, and additional bridges. Properties of bridges in the database were used to define the parameters for a parametric study on Western Washington bridges subjected to Magnitude 9.0 CSZ ground motions. Detailed multi-degree-of-freedom bridge models were developed with OpenSees. Models were formulated for a suite of representative bridges and used to conduct nonlinear time history analyses for synthetic ground motions that had been generated in previous studies. Results from the model analyses were used to provide a more detailed understanding of the likelihood of bridge damage and the likely service levels post-earthquake. Bridge response was limited in the longitudinal direction because of stiffness provided by the abutments and backfill soil. In the transverse direction, shear keys and bearings were found to limit the lateral deformation in columns as a result of participation of the bridge deck. The majority of bridges in the WSDOT inventory have shear keys and bearings and were predicted to be in full service following a CSZ earthquake. WSDOT has been retrofitting older bridge columns with steel jackets since 1991, and this retrofit has been shown to enhance ductility. Bridges without shear keys and bearings should be prioritized for retrofit. Shorter period bridges near the coast and longer period bridges in locations with sedimentary basins were also identified as being more prone to damage. Bridge functionality after a CSZ earthquake is likely to be considerably better than anticipated by the 2019 DHS report. Some bridges may require repair, but bridges are likely to remain useable for emergency vehicles and post-earthquake response. These conclusions were reached within the scope of the study, with several limitations noted in the report that will require further investigation.

Authors:
Motter, C.J., Phillips, A.R., Eberhard, M., Berman, J., Maurer, B.

Keywords:
Loss, damage, bridge, retrofit, earthquake, Cascadia Subduction Zone


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Wang, Y. 2023 PacTrans-WSDOT Summer High School Transportation Camp Program Report 2023 TRAC/UW
Abstract:
The primary objective of the PacTrans-WSDOT Summer High School Transportation Camp program is to promote an increased number of students pursuing advanced degrees and careers in STEM-related fields associated with transportation. This mission emphasizes a particular commitment to broadening the participation of women and minority groups within these fields. Ultimately, the program aims to contribute to the development of a skilled and diverse STEM workforce. The 2023 PacTrans-WSDOT Summer High School Transportation Camp was designed as a comprehensive, six-day, five-night residential program. It took place at two prestigious institutions: Washington State University (WSU) in Pullman from July 24th to 29th and the University of Washington (UW) in Seattle from August 13th to 18th. The 2023 program was generously sponsored by PacTrans and WSDOT and was offered free of charge to all participating students. Both camps welcomed 33 students, with 25 at the UW and eight at WSU. The success of both camps was underscored by overwhelmingly positive feedback from students and parents.

Authors:
Wang, Y., Li, J., Wu, L., Moudon, A.V.

Keywords:
STEM education, workforce development, high school, summer camp


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Hallenbeck, M.E. WA-RD 911.1 Community Engagement Support for the Highway System Plan Update 2022 TRAC/UW
Abstract:
This report documents the results of a statewide community outreach effort designed to help inform the Washington State Department of Transportation (WSDOT) about the spending priorities of state residents as part of WSDOT’s ongoing update of the Highway System Plan. The report documents the outcome of a statistically valid, statewide, discrete choice survey. In the survey, residents were given a hypothetical constrained budget and asked to allocate that budget across multiple funding categories. Survey respondents were allowed to select between multiple options for each funding category and were given information on the expected outcomes from each of those funding levels. The results were analyzed by geographic region of the state and by socio-demographic characteristics of the respondents. The responses documented in this report provide key insights for the plan’s update.

Authors:
Hallenbeck, M.E., Brown, R., Moudon, A.V.

Keywords:
Survey, Highway System Plan


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Eberhard, M. WA-RD 908.1 Impacts of Cascadia Subduction Zone M9 Earthquakes on Bridges in Washington State: Single-Degree-of-Freedom (SDOF) Ideal... 2022 TRAC/UW
Abstract:
The impacts on bridges of a magnitude 9 (M9) Cascadia Subduction Zone (CSZ) earthquake were evaluated to help prioritize earthquake retrofit efforts and support the development of emergency response plans. To evaluate these impacts, researchers developed single-degree-of-freedom (SDOF) models of typical pre-1976 and 1976-2018 bridges in Washington state. These models were subjected to ground motions from 30 simulated M9 scenarios, ten locations, and four sets of 30 site profiles. The mean calculated lateral strengths of the older and newer bridges were similar for a wide range of periods and exceeded the strengths expected from design procedures, even after the contributions of the abutments were neglected and material overstrength was accounted for. As expected, the older bridge columns had far less transverse reinforcement than the newer bridges. Near the CSZ, the damage was predicted to be widespread for a wide range of effective periods. The likelihood of column concrete spalling and longitudinal bar buckling ranged from 35-70 percent and 10-30 percent, respectively, with the larger values corresponding to softer site profiles. Far from the CSZ, the flexural damage to bridges was expected to be slight for locations outside of sedimentary basins. For most locations within sedimentary basins, such as Seattle, damage levels were predicted to be low for bridge periods below 0.5s. For bridges with periods of between 0.5s and 3s, the likelihood of concrete spalling ranged from 50-75 percent. For these long-period bridges, the likelihood of bar buckling ranged from 35-50 percent for softer sites and 20-35 percent for stiffer sites. This study did not account for the effects of bridge abutments, skew, or curved alignment. Note also that this study did not consider the possibility of span unseating, column shear failures, or site liquefaction, any of which could lead to bridge collapse.

Authors:
Eberhard, M., Kortum, Z., Liu, K-J, Berman, J., Marafi, N., Maurer, B.

Keywords:
Bridges, earthquakes, Cascadia, damage


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Wen, H. WA-RD 870.3 Long-Term Bond Characteristics of the Interface between Substrate and Overlay in Shotcrete Applications (Phase III) 2022 TRAC/WSU
Abstract:
Shotcrete is becoming popular for vertical and overhead applications where conventional formwork and repairs are difficult and costly. However, the substrate and the shotcrete overlay interface can be vulnerable, and the bond properties in this region are not well understood. Furthermore, the interface bond could be adversely affected by long-term freeze-thaw weathering in northern states leading to debonding from the existing substrate and corrosion of rebars. Hence, characterization of the shotcrete-substrate interface bonds is critical for the performance evaluation of shotcrete construction. To this goal, this study evaluated the shotcrete-concrete interface bond using four representative substrate surface preparation methods: chipped, pressure-washed, sandblasted, and as-cast, under three different loading conditions: tensile, shear, and Mode-II fracture. The study also investigated the long-term freeze-thaw durability of these bonds and introduced a probabilistic damage model to predict their service lives. The estimated surface texture depth and bond behavior are also correlated using laser texture scans of the substrate. Results indicate that the chipped substrates led to the highest interface bond strength and mode-II fracture energy. Out of the remaining surfaces, pressure-washing produced an interface bond that is more tensile-resistant, whereas sandblasting led to an interface bond that is more shear-resistant. Therefore, it is recommended to consider the actual loading application on the shotcrete-concrete interface bond when choosing appropriate surface preparation and testing techniques. Recommendations were proposed to include in the shotcrete specifications. Specifically, a tensile bond strength of minimum 145 psi from a direct tensile bond strength test (e.g., ASTM C1583) is recommended for overhead shotcrete application and a shear bond strength of minimum 300 psi from a direct shear bond strength test (e.g., AASHTO T323) for slope stabilization with shotcrete. Substrates with minimum estimated surface texture depths of 0.294 mm or larger (based on ASTM E2157 or D8271) or ICRI CSP No. 4 or higher led to bond strengths greater than 145 psi as specified by ACI. However, the predicted service life of shotcrete-concrete interface bonds is significantly reduced in regions prone to a higher number of freeze-thaw cycles. Therefore, methods to improve the long-term durability of bond strength need to be further investigated.

Authors:
Wen, H., Qiao, P., Manawadu, A.

Keywords:
Shotcrete, substrate to overlay, surface preparation, interface bonds


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Hallenbeck, M.E. Facilitating Analysts’ Use of Traffic Data from the Long-Term Pavement Performance (LTPP) Program 2022 FHWA
Abstract:
This report examines Long-Term Pavement Performance (LTPP) database users’ needs for traffic data and parameters and the extent of traffic data availability in the LTPP database. It identifies and recommends new analysis-ready traffic parameters and traffic data–usability indices for inclusion in the LTPP database. This report also presents a methodology for computation of analysis-ready traffic parameters selected by the Federal Highway Administration for this study and a methodology for assessing reasonableness of historical axle loading data included in LTPP database tables for sites that do not have sufficient information about the accuracy of equipment used to collect these data. This report includes a description of LTPP database tables that include newly computed analysis-ready traffic parameters. For LTPP sites that do not have traffic data, this report explores alternative data sources and provides recommendations for using these data sources. This report includes an overview of the User Guide for Selecting and Using Long-Term Pavement Performance Traffic Data, which aims to help LTPP database users navigate and understand LTPP traffic data and parameters and select or compute traffic parameters that best fit their project or analysis needs.

Authors:
Hallenbeck, M.E., Selezneva, O.I.

Keywords:
Traffic data, traffic loading, pavement design, Long-Term Pavement Performance, MEPDG, WIM, weigh-in-motion, HPMS


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Hallenbeck. M.E. Approaches to Target Setting for PM3 Measures 2022 FHWA
Abstract:
Targets and measures are key components of roadway performance management and are critical to communicating information about the transportation system to decision-makers, stakeholders, and the traveling public. Target setting for travel time-based measures has emerged as a challenge in transitioning to a performance management-based approach for making transportation investment and policy decisions, as mandated by the Moving Ahead for Progress in the 21st Century Act (MAP-21) and the Fixing America’s Surface Transportation (FAST) Act. This report provides potential approaches and resources to state departments of transportation and local agencies to help overcome those challenges. Approaches include technical options for developing the information to support target setting.

Authors:
Hallenbeck. M.E., Lindsey, C., Motamed, M., Margiotta, R.

Keywords:
Performance management , transportation investment, policy, target, target setting, stakeholders


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Reinhall, P. WA-RD 920.1 Design and Testing of Modular Expansion Joint Noise Mitigation Strategies 2022 TRAC/UW
Abstract:
This study investigated the design and feasibility of noise mitigation strategies for installation in modular expansion joints (MEJs), with a focus on Washington state’s SR 520 bridge. The three main sources of noise from MEJs include resonance of the air within the gaps, resonance of the beams, and resonance of the tires. By filling the gaps in the MEJs with engineered chevron support structures we have shown that it is feasible to significantly reduce the noise from MEJs. We performed both experimental and computer evaluations of a noise attenuation system before performing limited testing on the SR 520 bridge. Installation of the treatment on one westbound lane of the east MEJ of the SR 520 bridge proved to be highly effective over the two-month test period. At a distance of 160 feet, we measured a more than 70 percent reduction in audible noise over the noise of background traffic throughout the testing period. Beyond 160 feet the difference between noise from the concrete road surface and from the MEJ became so small that it became very difficult to identify when individual cars crossed the MEJ. While we have shown that the chevron system can be an effective solution to the expansion joint noise issue, we outline further development and testing to extend the durability of the treatment.

Authors:
Reinhall, P., Lipton, J., Thomas, S., Elmadih, W.

Keywords:
Bridge, Expansion joints, Noise control, Noise sources, Sound attenuation, Testing


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MacKenzie, D. WA-RD 918.1 Assessment of Electric Utility Capacity to Deliver Electricity for Electric Aviation at Paine Field and Grant County In... 2022 TRAC/UW
Abstract:
Advances in battery-powered electric motor systems, lightweight materials, and aircraft design have resulted in the development of new electric aircraft that could gradually replace conventional fuel-powered aircraft for certain uses in the coming years. In addition, a whole new category of electric vertical takeoff and landing aircraft has received billions of dollars of new investment, with the goal of serving an entirely new urban air mobility market that would allow for fast trips within congested metro areas. This study developed methods to estimate plausible future energy and power demand for electric aircraft operations at regional airports to determine whether the electric grid near two regional airports, Paine Field and Grant County International Airport, have the capacity to serve the potential energy (MWh) and peak power (MW) needs of electric aircraft operations over the next one to two decades. Our method has three parts: assumptions on flight operations growth, technical feasibility to serve these flights with electric aircraft, and actual adoption of electric aircraft to serve feasible trips. We found that the electric utilities serving these two airports have enough electric capacity at the neighboring substations to meet the demand for electricity over the next decade, given the capacities reported by the local utilities. Experience gained in the first decade of commercial electric aircraft deployment at these airports will help inform future analysis as to whether local grid capacity will eventually impede the growth of electric aircraft charging. Lastly, the report presents recommendations on how regional airports can prepare for electric aviation.

Authors:
MacKenzie, D., Coenen, S., Malarkey, D.

Keywords:
Electric aviation, electricity, projection, electric vertical take-off and landing, eVTOL, Paine Field, Grant County International Airport, Washington state


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MacKenzie, D. WA-RD 917.1 Assessing and Improving the Application of Multimodal Performance Measures in WSDOT Projects 2022 TRAC/UW
Abstract:
This report assesses the application of multimodal performance measures and indicators in WSDOT\'s design process. It characterizes the \"state of the knowledge\" as reflected in scholarly research on how best to achieve multimodal goals in projects. It characterizes the \"state of the practice\" by reviewing design manuals, guidebooks, and handbooks of leading state departments of transportation to better understand their methods and performance measures for implementing multimodal design. The report concludes with six case studies of multimodal projects across several WSDOT regions, evaluates how these projects integrated best practices for multimodal planning and performance measurement, and describes opportunities for improvement.

Authors:
MacKenzie, D., Arabkhedri, B., Malarkey, D., Tu, Y.

Keywords:
Multimodal, performance measures, planning and design, transit, bicycle, pedestrian


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Boyle, L. WA-RD 900.1 Advancing Multimodal Safety by Reducing Pedestrian Crash Potential 2021 TRAC/UW
Abstract:
Pedestrian safety is a priority of Washington State Department of Transportation’s (WSDOT) Target Zero Plan. This report provides the findings of the data used and the models developed to support our understanding of pedestrian safety. The project used data from WSDOT, the Census, the King County GIS Center, the University of Washington Urban Form Lab, and National Historical Geographic Information. The models created aimed to (1) identify factors and locations in Washington State that are associated with a higher number of pedestrian-vehicle crashes (frequency models) and (2) explore factors that contribute to pedestrian-vehicle crashes that result in serious injuries and fatalities (severity models). The outcome of interest for the frequency models was the number of pedestrian-vehicle crash(es) per 100-meter Euclidian buffer around intersection and non-intersection locations on state routes in King County, Washington, and in the entire State of Washington. Mixed-effects Poisson regression was used for these frequency models because the mean and variance of the outcome variable were not significantly different. The state route variable was treated as a random intercept to account for pedestrians’ characteristics that were specific to each state route. Microenvironmental factors that were positively correlated with the frequency of pedestrian-vehicle crashes included intersection type (intersection or non-intersection), being on a principal arterial road, total width of lanes, presence of a park and ride facility, and commercial area. The findings suggest that locations with these characteristics should be considered during rankings of locations within the pedestrian subcategory of the WSDOT I2 – Safety Program. Macroenvironmental factors (measured in a 400-meter buffer) that were negatively correlated with pedestrian-vehicle crash frequency included area household income and industrial land use. Higher-income households were related to a lower number of pedestrian-vehicle crashes, suggesting that reduction in crash potential should consider including identifying low-income neighborhoods. The Washington State model also accounted for state routes as a random effect. As expected, state routes within King County (SR 99, I-5) showed a higher number of pedestrian-vehicle crashes per 100-meter buffer. Binary logistic regression models were developed to examine the likelihood of pedestrian-vehicle crashes that result in serious injuries or fatalities. Older pedestrians (age groups: 45–64, 65–74, and 75+) involved in crashes were more likely to suffer serious injuries or to die than pedestrians in the age group 25–44. The likelihood of a pedestrian-vehicle crash resulting in serious injury or fatality increased when pedestrians failed to grant the right of way to vehicles, when drivers were moving straight ahead, and under dark light conditions. Crashes occurring on roads with speed limits higher than 40 mph were more likely to result in severe injury or fatality, while crashes occurring in park and ride lots and in areas of higher population densities were less likely to result in severe injury or fatality. Police crash reports often lacked information on vehicle speed, and pedestrians’ and drivers’ actions at the time of a crash. Complete and accurate crash reports will provide greater insights to enhance pedestrian safety.

Authors:
Boyle, L., Moudon, A.V., Haena, K., Mingyu, K.

Keywords:
Pedestrian safety, Pedestrian-vehicle crashes, Crash frequency, Crash severity, Regression models, Injury prevention, Geographic information systems


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Hallenbeck, M.E. Adjustments to the Public Records Act to Allow for Advanced Transportation Operations and Management 2021 TRAC/UW
Abstract:
This project developed recommended changes to the state’s Public Records Act that will enable the state’s public agencies, cities, and counties to obtain and use a variety of new electronic data—often collected by the private sector—that describe transportation system use of individuals, vehicles, and companies, without releasing to the public detailed data that could compromise the privacy of individuals and the trade secrets of companies. The State of Washington’s Public Records Act (PRA), passed as a public initiative in 1972, was designed to provide more transparency in the decision-making process at all levels of government. The law also directly acknowledges that citizens have privacy rights that deserve protections. However, the current version of the PRA was not written to account for the ways that modern technology has changed the collection of data and how those data are used for business applications and to manage the transportation system, as well as how unscrupulous individuals can abuse those data. This amendment should clarify privacy and trade secret protections of individuals and companies within the law, while maintaining transparency in government decision making, and should remove barriers to the sharing and use of private sector data to enable public agencies to more effectively manage the transportation system.

Authors:
Hallenbeck, M.E., Spitzer, H., Collins, B., Porton, A., Glaser, D.

Keywords:
Public records, Privacy, Transportation data, Transportation operations


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Caspi, A. Accessible Transportation Technologies Research Initiative (ATTRI) Performance Metrics and Evaluation: Evaluation Frame... 2021 FHWA
Abstract:
This report provides a framework that can be used to develop an evaluation of technology applications designed to remove barriers to transportation for people with visual, hearing, cognitive, and mobility disabilities. The framework helps evaluation teams follow a consistent process that starts with an understanding of 1) the goals of the technology; 2)the needs of the intended user population; and 3) the intended technical performance of the system, to create a logic model that identifies the evaluation hypotheses to be tested, the appropriate performance measures for evaluating those hypotheses, the data sources from which the required data can be obtained, and the areas where collaboration and agreement are needed between the evaluation team, the technology developers, and the evaluation sponsors to finalize and perform the evaluation. The framework specifically accounts for—and provides guidance for—evaluations of a wide variety of accessibility development projects (ADP) and is designed to help project sponsors, participants, and independent evaluation (IE) teams focus their evaluation efforts on the key outcomes of importance for each ATTRI-funded ADPs being studied, while also keeping in mind the need to understand the effect the ADP has on overall trip making capabilities of users. Thus, the framework is designed for use with all types of projects sponsored by U.S. Department of Transportation’s (USDOT) ATTRI Program.

Authors:
Caspi, A., Hallenbeck, M.E., Tyman, S.

Keywords:
Wayfinding, Pre-trip, Scenario, Logic model, Accessibility development projects


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Hallenbeck, M.E. Guidelines for Obtaining AADT Estimates from Non-traditional Sources 2021 TRAC/UW
Abstract:
This document provides decision making guidance that highway agencies can use to purchase or acceptance test traffic volume estimates such as annual average daily traffic (AADT) from the private sector when those estimates are based on non-traditional data sources, such as vehicle probe or smartphone data.

Authors:
Hallenbeck, M.E., Schewel, L., Co, S., Wergin, J.

Keywords:
AADT, probe data, volume, Big Data, LBS, GPS, machine learning, MADT, volume, AADTT, K-Factor, D-Factor, AAHT


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Moudon, A.V. Longitudinal Analyses of Washington State Student Travel Surveys 2021 PacTrans
Abstract:
Part of a long-term collaboration between the University of Washington (UW) and Washington State Department of Transportation (WSDOT), this project contained two studies: (1) longitudinal changes in active school transport (AST) rates and (2) impacts of Safe Routes to School (SRTS) projects on AST rates. (1) The average rate of AST for the 241 schools surveyed in 2016 was 21.2 percent, compared to 14.1 percent for the 198 schools surveyed in 2019. The difference in rates was explained primarily by the difference in the schools sampled in the two waves. For the 32 schools that were included in both surveys, rates were similar at 22.3 percent in 2016 and 19.8 percent in 2019. Schools included in only the 2019 survey lacked characteristics that are known to be associated with higher rates of AST: their neighborhood had lower street connectivity; they offered less encouragement for AST; their students were younger; and a higher proportion of them lived farther from school. Differences in walkability scores and walking potential scores between the two waves further confirmed these findings. (2) Evaluating the association between rates of AST and SRTS project awards was based on 94 projects with complete project information from multiple databases. Most projects (N=53) were accompanied with increases in students walking to/from school; 40 had increases in the number of students biking. For other projects, decreases were observed (N=17 for walking; N=18 for biking). On average, schools with SRTS projects had a 33 percent increase in the number of students walking and a 104 percent increase the number of students biking. Regarding project type (with primarily an engineering, education, or enforcement component), larger effects were found for education projects (17 percent and 37 percent increases in walking and biking, respectively) and enforcement projects (2 percent and 115 percent increases in walking and biking). However, these findings have limited generalizability because of the small sample size (N=32).

Authors:
Moudon, A.V., Shi, X.

Keywords:
Active transportation, school trips, travel surveys


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Moman, A. Use of a Microwave Method to Prototype Electrically Conductive Concrete 2021 PacTrans
Abstract:
Electrically conductive pavement materials have shown potential as self-deicing pavements under passed electrical current. In this project, a method using microwaves was used to evaluate the electrical conductivity of pavement materials for the purpose of melting snow and ice and reducing the need for sanding and salting in the winter. The preliminary experiments in this study found the potential of the method to detect conductive mixes. The prototyped electrically conductive concrete (ECC) assessed in this study contained 0.2 and 0.3 percent weight of carbon fibers. Concentrations of 0.2 and 0.3 percentage by weight (wt%) resulted in more conductivity than a neat mix, while a decline in conductivity at 28 days was obtained for 0.4 wt%,indicating a potential percolation limit of between 0.3 and 0.4 wt%. The small samples and the quick, nondestructive method of measurement can be used to easily identify the optimum dosage and percolation limits of various conductive fibers for ECC development. Future investigations may include using this method to further determine the best fiber content to optimize electrical-thermal performance with maximum mechanical properties and durability.

Authors:
Moman, A., Nassiri, S.

Keywords:
Self-deicing pavements, electrically conductive concrete


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Kastner,S. WA-RD 899.1 Ferry Vessel Propeller Wash Effects on Scour at the Kingston Ferry Terminal (Washington) 2020 TRAC/UW
Abstract:
This project investigated the hydrodynamic causes of severe erosion at the Washington State Ferries ferry terminal in Kingston, Washington, where a cliff-like bathymetric feature had shifted shoreward in recent years, forcing repairs on the slip\'s bridge pilings. High resolution measurements of velocity and estimates of turbulent bed stress were taken during vessel arrivals and departures during two deployment periods in March and April 2018. Calculated bed stresses (and maximum velocities) were found to be 10 to 100 (30 to 50) times larger during vessel arrivals and departures than background levels. The structure of the wash was modified by the bathymetry such that steeper bathymetry led to more reflection of the propeller wash. Bed stresses were higher during vessel departures than arrivals, corresponding to higher vessel acceleration during departures. Additionally, during departures, lower tidal states corresponded to higher bed stresses because the propellers were closer to the seabed. During arrivals, larger vessels generated higher bed stresses. In this work, we developed, assessed, and used an empirical model for bed stress that took into account these dependencies. Using this model, we determined that the most important factor for cumulative vessel stress is the frequency of use of a given slip. Additionally, shallower ground lines will be exposed to higher bed stress than deeper ground lines, so modifications to the existing bathymetry should take into account both the effect of shallower depth and milder slope.

Authors:
Kastner,S., Stearns,C., Horner-Devine,A., Thomson, J.

Keywords:
Hydrodynamics, wakes, turbulence, scour, ferry terminals, vessel operations


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Hallenbeck, M.E. Evaluation of the Use and Performance of Via to Transit in the Puget Sound Region 2020 TRAC/UW
Abstract:
Sound Transit and King County Metro teamed as sub-recipients on a project led by Los Angeles Metro to demonstrate the viability of a partnership with a private sector transportation network company to increase access to transit through the provision of on-demand, first-mile/last-mile transit access services. This independent evaluation report concentrates on the actual ridership impacts of the Via to Transit service; that is, how many people chose to use Via, whether those individuals represented all segments of the population living in the study area, and whether the availability of the Via service for first-mile/last-mile trip making changed their use of Link light rail or bus.

Authors:
Hallenbeck, M.E., Van Roijen, A., Avery, R., Zyuzin, D.

Keywords:



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Engdahl, N. WA-RD 903.1 Flume-Based Design Recommendations for Coarse Bands and Boulder Bars to Improve Retention of Channel Shape in Stream Sim... 2020 TRAC/WSU
Abstract:
The Pacific Northwest has seen a reduction of fish populations related to the number of fish barriers in the area. In response, Washington State implemented new design policies in 1999 to replace the most common barriers, culverts. New “stream simulation culverts” incorporate a sediment lining, providing an environment more conducive to fish movement. Streambed design must balance engineering and ecosystem factors, but there is little guidance on how to maximize the lifespan of the overall channel shape while providing maximum fish passage during low water flows. This research investigated how to incorporate coarse material (coarse bands and boulder bars) into a simulated streambed in a flume. The first objective examined whether coarse bands and boulder bars could stabilize a channel without eliminating sediment transport. Three characteristics were tested: coarse material size, the number of coarse bands, and the spacing between coarse bands/boulder bars. The second objective was to investigate relationships between the number and spacing of coarse bands/boulder bars and channel stabilization. Streambeds were subjected to one-, two-and-a-half-, five-, and ten-year flood frequency events. Sediment transport was quantified after each flood event by using cross-section profiles and was analyzed to determine net change for each cross section. Thirty coarse bands and twelve different boulder bar configurations were tested with variable numbers of coarse bands/boulder bars and amounts of spacing and stream slope relative to a uniform streambed (without coarse bands). The research showed that nearly linear, coarse bands that fully spanned the channel reduced sediment transport by 56%, 54% and 50% at bed slopes of 2%, 3%, and 4%, respectively, conditional to differences in the geometry of the coarse bands at each slope. Boulder bars spaced one channel width apart produced sediment transport reductions of 49%, 57%, and 33%, at bed slopes of 2%, 3%, and 4%, respectively, and produced different transport patterns than the linear designs. These findings indicate that minimal additions of coarse bands reduced sediment transport and generally maintained U-shaped channels. Coarse band/bars at greater bed slopes required larger material and armoring layer downstream to prevent destabilization/failure.

Authors:
Engdahl, N., Fouty, T., Kelty, B.

Keywords:
Coarse bands, stream simulation design, water resources, fish barrier, sustainability


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Muench, T. WA-RD 912.1 RAP Reset – Responsibly Optimizing Recycled Materials Use in Asphalt Concrete and Pavement Performance Life 2020 TRAC/UW
Abstract:
The durability performance of asphalt concrete (AC) with various percentages of reclaimed asphalt material (RAM) has been a focal point of the asphalt industry, leading it to embrace the balanced mix design (BMD) concept. The goal of this research was to review and enhance WSDOT\'s AC materials selection, mix design, and standard specifications for optimized use of RAM, based on readily implementable technology, in collaboration with industry stakeholders for improved durability performance. The scope included a literature review, an assessment of RAM supply in the state, and a statewide comparison of low and high RAM pavement performance data to determine whether differences were observed;. The scope also included an evaluation of raw materials and field mixtures and an evaluation of laboratory mixed-laboratory compacted (LMLC), field mixed-laboratory compacted (FMLC), and field cored (FMFC) samples. The laboratory analysis included short-term and long-term aging of binders and mixtures with rheological and cracking tests performed on them. One recommendation of the study was to integrate volumetric parameters along with further performance testing in a BMD approach to increase effective binder content. Another was to implement all of the volumetric criteria in AASHTO M323 during mix design, test section and acceptance. Additional recommendations were to use ΔTc as an aging parameter in binder specifications; include RAM in all mix designs regardless of doses; maintain an IDT strength specification and transition to the CT-Index; add long-term aging for IDT/CT-Index test specimens in the future, maintaining the current Hamburg Wheel Track (HWT) rutting test and criteria; revise short- and long-term standard specification; and re-evaluate the performance of RAM pavements with time.

Authors:
Muench, T., Hand, A., Sebaaly, P., Hajj, E., Chhetri, K., Piratheepan, M., Elias, N., Howell, R., DeVol, J., Davis, S,

Keywords:
Asphalt concrete, performance, recycled asphalt materials, durability


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Moudon, A.V. Washington State School Walk Score 2020 PacTrans
Abstract:
We used unique data from the 2016 Washington State Student Travel Survey combined with built environment data to first confirm the factors shown to influence children walking to and from school in previous literature. Walkability scores were then estimated for K-8 Washington state schools under different data availability scenarios. First, models were developed using the 66 schools in King County with both student travel data and extensive built environment data that could serve as “best case” scenarios for calculating walkability indices. The models were run for three additional scenarios that reflected the limited data available in the state outside of King County. Second, models with limited data were run for the 159 remaining schools in Washington state that had student travel data. A Walkability Score applied to all K-8 schools was based on two built environment characteristics: street connectivity (route directness) and vehicular traffic exposure (ratio of major/minor streets); as well as school total enrollment as a control variable. A Walking Potential Score estimating the percentage of children likely to walk at each school was calculated by adding the percentage of children in the school lunch program and the number of children riding the school bus to the variables used in the Walkability Score. The average Walking Potential Score was 21.5 percent (SD 16.1 percent) of the students in a school walking to or from school. To our knowledge, no other state has scored their schools for walkability. The scores can guide the future allocation of funds to support and promote walking to school in two ways: they can help rank schools according to the need for increasing their rate of walking; and they can identify those components/indicators of the school neighborhood environment that could be changed to most effectively increase the likelihood of children walking to school. An appendix provides a tally of Walkability and Walking Potential Scores for K-8 schools in Washington state by county and by school district.

Authors:
Moudon, A.V., Shi, X., Chen, Y.

Keywords:
Walking to school, school walkability score, school walking, potential score


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Pimentel, R.W. If You Provide, Will They Ride? Motivators and Deterrents to Shared Micro-Mobility 2020 PacTrans
Abstract:
Bike share, e-bike share, and e-scooter systems (shared micro-mobility) are gaining popularity throughout the United States and internationally, but the optimal system design has not been determined. This study investigated motivators for and deterrents to the use of such systems in the Pacific Northwest by using a research framework from consumer behavior theory with secondary data, participant observations, in-depth interviews, and an on-line survey of users and non-users. The survey was administered in all cities in Washington, Oregon, and Idaho that have shared micro-mobility systems. Convenience and social good were found to be major motivators, but the strongest motivators reported were exercise and enjoyment. The strongest deterrents were weather, danger from automobile traffic, and insufficient bike lanes and paths. The latter two deterrents might be alleviated through continued improvements to infrastructure; however weather cannot be changed and neither can hills. Nevertheless, the survey suggested that those issues might be addressed by promoting the popular motivators of exercise and enjoyment. Once riders have become accustomed to using and enjoying the shared services in favorable conditions, they may be more likely to figure out ways to deal with weather and hills. Any promotional activities should be targeted to the “interested but concerned” segment of the four types of cyclists, as it represents the greatest potential for increased ridership, and should emphasize personal benefits more than social appearances.

Authors:
Pimentel, R.W., Lowry, M.B.

Keywords:
Shared mobility, vehicle sharing, bicycles, bicycle riders, scooters, safety, risk, interdisciplinary studies


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Moudon, A.V. The Impact of Shared Mobility Options on Travel Demand 2020 PacTrans
Abstract:
Newly available shared mobility options are having a large impact on travel. Car- and bike-sharing and ride-hailing have become increasingly viable and attractive travel modes since they have been app-based and able to link riders and vehicles in real time and space. This project aimed to provide much needed information on how app-based shared mobility options are affecting travel behavior, and specifically how they are changing the parameters leading to mode choice and mode share. We used three available secondary data sets to explore whether shared mobility options substitute for or complement traditional modes. The first set of data came from the 2017 Puget Sound regional Household Travel survey. We found that car-sharing and ride-hailing substituted for household vehicle trips. Yet they induced more travel, which could add to traffic congestion but could also improve access to activities. Substitution effects with transit and biking, and additional walking, differed by day of week and commute status, suggesting that future research focus on the temporal and purpose characteristics of trips by shared mobility. The second set of data came from the Washington State Commute Trip Reduction (CTR) program. We found that in the immediate, CTR instruments used to collect data on commute trips could add questions about shared mobility options. In the long run, CTR employer and employee surveys could be redesigned to facilitate the evaluation of employers’ TDM efforts. Also, deploying apps to support the commute trip could yield invaluable and timely information for transportation policy and research. The third set of data addressed “shared micro-mobility,” an increasingly popular form of shared mobility that includes bicycles and scooters. Companies that offer this service have dispersed hundreds or even thousands of bicycles and scooters across individual cities for customers to use. A few companies provide real-time location data for their bikes and scooters via the Internet. We created a computer program to continuously “scrape” and archive such data. A technical description of the online database system was provided. A pilot-study served to analyze one year of data and to create trip generation models.

Authors:
Moudon, A.V., Ban, X.J., Lowry, M., Shen, Q., Mills, M., Sun, F., Wang, Y.

Keywords:
Shared mobility, micro-mobility, car sharing, bike sharing, ride hailing, commute trip reduction, travel surveys, transportation demand management, TDM


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Ishimaru, J. WA-RD 888.1 QUEWZ Work Zone Software: Methodology and Literature Review 2019 TRAC/UW
Abstract:
This report documents the results of a literature review and methodological analysis into the design and technical basis of the QUEWZ work zone road user cost estimation software tool. The report documents how key formulas/algorithms within the QUEWZ software were derived, describes ways that QUEWZ could be updated, and summarizes the literature regarding comparisons of QUEWZ with other tools used to evaluate work zone road user costs.

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

Keywords:
Construction traffic, Construction traffic delay estimation, QUEWZ, HCM, Work zones


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Phillips, A. WA-RD 890.1 Field Analysis of Wood Guardrail Post Decay 2019 TRAC/WSU
Abstract:
Wood guardrail posts can be inspected for decay using a non-destructive testing (NDT) technique called stress wave timing (SWT). This project conducted a field investigation on approximately 500 wood guardrail posts using SWT and then analyzed available data to determine factors that may lead to increased wood decay rates. It was determined that locations with high climate index (> 40) experienced higher decay rates. Additionally, poor preservative retention levels were also found to be associated with high decay rates. Impact testing concluded that decay reduces the fracture resistance of wood posts by more than 50 percent. The results of this report will be useful in considering approaches to managing WSDOT guardrail assets in the future.

Authors:
Phillips, A., Luo, Q.

Keywords:
Nondestructive testing (NDT), Stress wave timing (SWT), Wood, Guardrail, Pendulum impact testing, Fracture energy


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Hallenbeck.M.E. I-405 Express Toll Lanes: Usage, Benefits, and Equity 2019 TRAC/UW
Abstract:
Using data on each trip made on the I-405 express toll lanes during all operational hours (weekdays 5:00 AM – 7:00 PM) of 2018, demographic data by census block groups, plus speed, volume, and travel time data for both the express toll and general purpose lanes, this study examined how the express toll lanes are used, the benefits they provide to users, and how these benefits are distributed among different groups of noncommercial users. The project used data from over 16 million trips on the facility. The result is unique insight into facility usage patterns and equity impacts associated with different income and geographic groups.

Authors:
Hallenbeck.M.E., Leung, S., McCartan, C., Robinson, CJ, Zamir, K.R., Iverson, V.

Keywords:
Express lanes, Toll lanes, HOT lanes, Elasticity, Equity, Usage


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Goodchild,A. Curb Allocation Change Project 2019 Urban Freight Lab
Abstract:
Like many congested cities, Seattle has experienced a rapid increase in ride-hailing trips by transportation network companies (TNCs) such as Uber and Lyft. That increase has raised broad concerns about congestion, safety, and effective curb use. In response, this study looked at a strategy to manage TNC driver stops and improve traffic flow when passengers are picked up and dropped off in the South Lake Union area of Seattle. To mitigate the impacts of passenger pick-up/drop-off activity on traffic, the city proposed a strategy of increasing passenger loading zone (PLZ) spaces in South Lake Union, while Uber and Lyft would implement a geofence to direct their drivers and passengers to designated load and unload locations. The study found that passenger loading and unloading made up a significant share of total vehicle activity in the study area. Without dedicated load/unload curb space, TNC vehicles stopped and waited at paid parking spots and in other unauthorized curb spots. A significant percentage of vehicles also stopped in the travel lane, potentially blocking or slowing traffic. Adding PLZs and geofencing was found to increase driver compliance in stopping at the curb versus stopping in the travel lane to load/unload passengers. Adding PLZs and geofencing also reduced the average amount of time drivers stopped to load/unload passengers. In addition, adding PLZs and geofencing did not have a significant impact on traffic safety, and it did not produce a significant impact on roadway travel speed.

Authors:
Goodchild,A., MacKenzie, D., Ranjbari, A., Machado, J., Dalla Chiara, G.

Keywords:
Parking, curb, transportation network companies, passenger load zones


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Kim,A. WA-RD 898.1 Linear Scheduling Evaluation and Best Practices Development: Phase I Report 2019 TRAC/UW
Abstract:
A relevant literature review was conducted of best practices related to the use of the linear scheduling method (LSM) for heavy civil construction projects. The comprehensive literature review revealed an additional need to understand how LSM could be best utilized for WSDOT, which will include conducting an investigation into off-the-shelf software programs that could be integrated with existing platforms that WSDOT currently uses.

Authors:
Kim,A., Wang,S., Medal,L., Sadatsafavi,H.

Keywords:
Linear scheduling method, linear scheduling software, performance measurement framework, visualization, benefit-cost analysis


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Hallenbeck,M.E. WA-RD 894.1 WSF Triangle Route: Analysis of Alternative Concepts of Operations 2019 TRAC/UW
Abstract:
The Washington State Ferry System Triangle Route (Fauntleroy – Vashon – Southworth) is heavily used and experiences a number of significant operational challenges. This report documents the outcome of a project tasked with examining different concepts of operation that would improve the performance of the Triangle Route, with a specific focus on the Fauntleroy terminal during periods of peak use. Each concept of operation describes operational procedures designed to improve the speed and efficiency of the terminal’s operations, the vessels’ load factor, the vessels’ on-time performance during peak travel periods, and if possible, the peak period capacity of the route. A variety of recommendations are made for consideration by Washington State Ferries for projects that might improve both the overall operational performance of the route and customers\' overall satisfaction with their experiences when using the route.

Authors:
Hallenbeck,M.E., Scott,E.

Keywords:
Ferry system, ferry operations, ferry revenue collection


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Wang,Y. WA-RD 885.1 Understanding Opportunities with Connected Vehicles in the Smart Cities Context 2019 TRAC/UW
Abstract:
This research focused on using connected vehicle information to identify locations prone to conflicts between motorized and nonmotorized users to improve traffic safety on multimodal roadway networks. With this information in hand, transportation system users can be alerted of potential conflicts they may be involved in, before their occurrence, allowing these users to take preventive actions by making evasive maneuvers. A comprehensive review of the literature investigated existing connected vehicle (CV) and vehicle-to-X (V2X) safety applications. The methods to allow a sensor to communicate via both dedicated short range communications (DSRC) and via Bluetooth, WiFi, or another communication protocol commonly used by mobile devices were also investigated, as well as existing surrogate safety measures and their use in conflict- and safety-prediction algorithms. The review indicated that several studies have focused on the safety and operational benefits of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications; however, the safety benefits of V2X communications have not been sufficiently explored. In this project, a cost-effective, solar-energy driven, small, and lightweight communication node device, called the Smart Road Sticker (SRS), was developed to enable communications between connected vehicles and other roadway users via protocols such as LoRa and Bluetooth, and potentially DSRC. A supporting mobile application that allows pedestrians, bicyclists, and drivers of unconnected vehicles to communicate with the SRS device and vice versa was also designed. A crash risk prediction algorithm, with applications for vehicle/non-motorized user crashes, was developed to identify unsafe conditions and determine appropriate CV-based safety countermeasures for system users. Next, a connected vehicle simulation test bed was established in VISSIM to evaluate the safety benefits of the proposed methodology under various traffic and landscape conditions. The findings of this study were that the number of conflicts increased when the penetration of connected devices decreased. In addition, increasing the traffic volume had a direct relationship with increasing the number of conflicts. Finally, a real-world test bed was established for installation of sensors, data collection, and analysis, as well as to initiate further smart cities research within the state.

Authors:
Wang,Y., Ash,J., Zhuang,Y., Zhibin,L., Zeng,Z., Hajbabaie,A., Hajibabai,L., Tajalli,M.

Keywords:
Safe traffic operations, connected vehicles, communications node device, mobile applications, crash risk prediction algorithm, simulation test bed


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Okere, G.O. A Construction Project Classification Framework: Mapping the Dimensions for Classification of Pacific Northwest Highway ... 2019 PacTrans
Abstract:
In the construction industry, it is an accepted fact that not all projects are created equal, so analysis and evaluation of project performance should follow the same principle. Gaining insights into contract performance requires practitioners to compare project performance on various dimensions, look for patterns, and make generalizations. In contract administration, practitioners are interested in project performance as it relates to cost, time, quality of work, scope of work, and contract changes. A standard project type classification framework that would allow such comparisons does not exist for use by practitioners working on highway projects. In the absence of a standard project type classification framework, practitioners have taken the pragmatic and ad hoc steps to classify projects to meet their specific needs. The lack of a standard project type classification framework makes it difficult for practitioners who administer highway projects to effectively gain insights, find patterns, generalize findings, extend knowledge, and transfer knowledge gained. Following qualitative synthesis research and participation from Pacific Northwest (PNW) state departments of transportation (DOT), a project type classification framework was developed. The proposed project type classification framework captures the differentiating dimensions and corresponding measures that define highway projects. A data input wireframe was also developed for implementing the project type classification framework into a searchable database. The significant contribution of this study was that basic project performance analytics can be enhanced by using the project type classification framework. In addition, the proposed project type classification framework would eliminate the use of ad hoc classification systems. It is recommended that future research focus on evaluating whether the proposed project type classification framework enables better visibility of and insights into contract administration.

Authors:
Okere, G.O.

Keywords:
Highway project types, contract administration, highway project classification framework, database of highway project types


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Nassiri, S. Development of Protocol to Maintain Winter Mobility of Different Classes of Pervious Concrete Pavement Based on Porosity 2019 PacTrans
Abstract:
The main focus of this study was to develop an image-based method to characterize the porosity of in-situ pervious concrete (PC), so this feature can be correlated with ice formation and winter maintenance operations of the pavement. First, a surface imaging-based porosity characterization method was investigated. A total of 27 PC slabs cast at three targeted porosity levels—15 percent, 25 percent, and 35 percent--were used. Images of the top and bottom surfaces of the slabs were used in thresholding techniques, in which the images were binarized and the area of the voids were obtained. The image-based porosity was calculated as the ratio of the area of voids to the total surface area of each slab. The image-based porosity was correlated with the porosity of the PC measured in accordance with ASTM C1754 by submersion. For validation, the distribution of the porosity along the depth of PC cores extracted from the slabs was quantified from images taken by X-ray computed tomography (CT). Analysis of these images revealed that the distribution of pores along the depth were significantly different at intermediate depths than that at the top and bottom 0.5-inch depths because of compaction. Therefore, the developed surface image-based method did not provide a representative porosity value for the full PC layer. More surface imaging, in parallel with X-ray CT scans, are required to develop a correlation between the porosity of the surface layer and overall porosity. Finally, the Gibbs-Thompson equation, a thermodynamic-based model developed in past studies, was recommended to determine the critical temperature at which ice formation initiates inside PC pores. The proposed image-based porosity characterization method and the Gibbs Thompson equation can be used as a decision support tool for transportation authorities to identify the time of ice formation in PC pavements in order to apply timely winter maintenance treatments.

Authors:
Nassiri, S., Alshareedah, O.

Keywords:
Pervious concrete, porosity, X-ray, computed tomography, image analysis


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Qiao, P. Development of Surface-Mounted Smart Piezoelectric Modules for Condition Assessment of Bridges 2019 PacTrans
Abstract:
In-situ, real-time structural health monitoring (SHM) of civil infrastructure via piezoelectric materials (PZT) is an emerging, sustainable method to ensure structural safety and integrity. In this study, a smart surface-mounted PZT patch system and an embedded PZT cement module system were developed to determine the wave modulus of elasticity (WMoE) of concrete through a combined experimental and numerical investigation. Concrete beams and a concrete panel were evaluated to identify the feasibility of utilizing the two smart PZT systems to determine the WMoE at different ages. The key parameter of the study was to determine the time of flight (ToF) of the first Rayleigh wave (R-wave) package from the surface-mounted PZT patch system or the first shear wave (S-wave) package from the embedded PZT cement module system of propagating waves. The experimentally measured WMoE from the two smart PZT systems were about 11 percent (maximum) higher than the SMoE of the concrete obtained from the compression test. The experimental results also indicated that the surface-mounted PZT patch system produced higher WMoE values than the embedded PZT cement module system, but within a range of 4 percent. The orientation of the embedded PZT cement modules affected the clarity and magnitude of the propagating wave. The established FE model for beams validated the results of the experimental evaluation. The measured WMoE also varied with the dimensions of the structures, and the WMoE values measured from a narrower, deeper structure were smaller than the ones from a wider, shallower structure. Overall, the surface-mounted PZT system proved to be as effective as or even better than the embedded PZT cement module system in determining the of WMoE concrete with a certain degree of confidence and in assessing concrete properties.

Authors:
Qiao, P., Manawadu, A.K., Zhou, Z.

Keywords:
Structural health monitoring, piezoelectric, concrete, wave modulus of elasticity


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Haselkorn, M. WA-RD 878.1 Coordinated Traffic Incident and Congestion Management (TIM-CM): Mitigating Regional Impacts of Major Traffic Incidents ... 2018 TRAC/UW
Abstract:
Within the Seattle metropolitan area, traffic incident management (TIM) operations provide a multi-jurisdictional and coordinated strategy to detect, respond to, and clear traffic incidents so that traffic flow can be restored quickly and safely. There is a need to extend TIM to include congestion management (CM), a complex activity for managing incident-generated congestion and for mitigating regional impacts after the actual incident has been cleared. This project identified challenges and opportunities for the enhancement of regional TIM to incorporate CM processes and operational coordination, supported by innovative technologies. The researchers engaged regional stakeholders in a series of iterative scoping and participatory design activities to identify and articulate desired enhancements to the regional management of major incidents on the Seattle I-5 corridor. These activities were used to identify TIM and CM stakeholders, identify and review relevant policy, work with stakeholders to model the “as-is” TIM and CM processes and procedures, use the as-is model to facilitate stakeholders in identifying current pain points and opportunities for system enhancement, and articulate desired interventions made possible by innovative applications of emerging technology. The report includes recommendations for enhancing regional TIM to incorporate CM and a five-stage approach for conducting Phase 2 of this research.

Authors:
Haselkorn, M., Yancey, S., Savelli, S.

Keywords:
Congestion management systems, Traffic incident management, Transportation management


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Chowdhury, I. WA-RD 816.4 Mechanisms Involved in the Removal of Heavy Metals from Stormwater via Lignocellulosic Filtration Media 2018 TRAC/WSU
Abstract:
This report aims to supplement our previous report (Yonge et al. 2016; WA-RD 816.3) that assessed copper and zinc adsorption to lignocellulosic filtration media using laboratory tests and field-scale column tests for urban stormwater remediation. The current project extends the species of wood materials that were investigated in the earlier study. We performed laboratory tests using Douglas-fir crumbles®, poplar crumbles®, tanoak crumbles®, lodgepole pine crumbles®, Ultra-char of poplar®, Ultra-char of alder®, and Ultra-char of Douglas-fir® to evaluate their ability to adsorb copper and zinc. The laboratory column test results indicated that the most efficient adsorption medium for both copper and zinc is ultra-char of poplar, followed by tanoak crumbles, poplar crumbles, ultra-char of Douglas-fir, Douglas-fir crumbles, lodgepole pine crumbles, and ultra-char of alder, in that order. However, the batch experiments showed that tanoak is the most efficient adsorption medium of the samples tested. Based on the summary results of both the column and batch experiments, among all the samples of wood crumbles and char, tanoak crumbles seem to be a better option for metal adsorption. One of the most important conclusions drawn from this project is that the surface areas of both wood crumbles and ultra-chars of different wood crumbles are highly relevant to their ability to adsorb copper and zinc. Building on our previous research, we found that surface area is a critical parameter for copper and zinc removal, and the role of functional groups is not as important as we had expected. Typically, chars have larger surface areas and fewer functional groups than wood crumbles. The presence of functional groups would favor metal adsorption when two materials share similar surface areas, which may explain the superior adsorption performance of raw wood crumbles over char that we reported in our previous report (Yonge et al. 2016).

Authors:
Chowdhury, I., Tian, Y., Shams, M., Wolcott, M., Dooley, J.

Keywords:
Stormwater, ferry terminals, filtration, copper, zinc, Washington State


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Tsvetanova, K. WA-RD 867.1 Developing Extended Strands in Girder-Cap Beam Connections for Positive Moment Resistance 2018 TRAC/UW
Abstract:
In bridges constructed with precast prestressed concrete girders, resistance to seismic effects is achieved by the interaction between the columns, the cap beam and the girders. These components must be connected to provide flexural resistance. Under the impact of longitudinal seismic motion, the bottom flanges of the two girders that meet end-to-end at the cap beam will be under tension and compression, respectively. The tension connection between bottom girder flange and cap beam is presently made by extending some of the bottom strands into the cast-in-place diaphragm. At this location, the space available is too small for development by bond in the straight strands alone, so some form of mechanical anchorage is needed. Since concrete in the diaphragm is highly confined, it can probably carry high bearing stress and an anchor with a small bearing area may be possible. Thus, the goal of this project is to create a reliable, effective, as well as practically applicable, way of anchoring strands extended from the girder into the cap beam. The first stage in the development of the girder-diaphragm seismic connection consists of establishing the adequacy of the smallest possible strand anchor that still leads to a strand ductile failure due to yielding rather than strand anchor failure by crushing of the concrete. As a second stage, the impact of the possible failure mechanisms of the strands, embedded in the diaphragm, on the development of the girder-cap beam positive moment connection was investigated. Finally, the distribution of girder bending moments across the bridge deck was evaluated, while investigating the influence on that distribution of the most important bridge parameters, such as cracking of bridge components, as well as varying cross sectional dimensions.

Authors:
Tsvetanova, K., Stanton, J.F., Eberhard, M.O.

Keywords:
Longitudinal seismic resistance, Positive moment, Extended girder strands, Girder-cap beam connection, Precast prestressed concrete girders, Strand anchorage bearing capacity


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Jessup, E.L. WA-RD 877.1 Improved Methodology for Benefit Estimation of Preservation Projects 2018 TRAC/WSU
Abstract:
This research report presents an improved process for evaluating the benefits and economic tradeoffs associated with a variety of highway preservation projects. It includes a summary of results from a comprehensive phone survey concerning the use and application of the software developed by the Federal Highway Administration (FHWA), known as the Highway Economic Requirement System (HERS-ST). This national survey revealed that only a few states utilize this software in evaluating highway preservation projects and revealed an existing need to bridge pavement management and economic impact analyses in the evaluation of highway preservation projects. This research project developed a supplemental software application tool within Excel to improve the HERS-ST software and enhance the capabilities of evaluating highway preservation project analyses. This software application, the HERS-ST Benefit Application Tool (HERS-ST-BAT), has been developed to enhance and improve upon the project evaluation process. By combining HERS-ST-BAT and HERS-ST, the analyst is able to provide estimates for a variety of regional- level agency and user costs associated with preservation programs and more effectively consider different investment alternatives. Three separate preservation project case studies are selected to apply the HERS-ST- BAT and detailed results presented.

Authors:
Jessup, E.L., Zhou, Y., Lang, E.

Keywords:
Highway preservation, economic analysis, user benefits


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Moudon, A.V. WA-RD 882.1 Safe from Crime at Location-Specific Transit Facilities 2018 TRAC/UW
Abstract:
Transit agencies identify two types of exposure to crime: the safety of riders and security. Transit operators have long monitored crime and are cognizant of high incident locations. However, they lack data-driven tools to readily match crime events spatially with the locations of individual transit facilities, and temporally with transit service periods. This pilot project explored the use of data-driven tools to (1) identify concentrations of criminal activity near transit facilities, and (2) assist decision-making regarding the selection of countermeasures and the allocation of future safety investments, using the results of models estimating environmental and socioeconomic predictors of crime near transit facilities. The project used two novel data sets: location-specific, police-reported crime incidents by type; and individual ORCA card (electronic transit fare payment system) transaction records, yielding transit ridership data. Two sets of models were developed to examine exposure to crime while waiting for transit (within 100 m from transit stops) and while walking to transit (within 400 m from transit stops). The hypotheses were that within 100 m of a stop, amenities at stops act as deterrents of crime; and within 400 m different characteristics of the built, social, and transportation environment are associated with crime. Analyses were restricted to the City of Seattle, and models were run using all stops and only stops located in the City’s urban villages (hosting 90 percent of the City’s ridership and the stops with the most crime). We found that amenities at stops have mixed associations with crime, suggesting that amenities serve to provide riders with added comfort but not necessarily more safety. Higher ridership provides safety while waiting for transit (100-m models) but exposes riders to more crime as they walk to and from transit (400-m models). In urban villages, sidewalks are associated with a lower likelihood of crime. However, a more connected street network, which characterizes the oldest, most urban areas of Seattle, is associated with more crime. The project illustrated how novel sets of disaggregated data on both crime and transit ridership can serve to develop models assessing the safety of transit riders at specific locations. Future research should continue to examine how transit riders can be protected from crime while they wait for transit as well as while they walk to and from it.

Authors:
Moudon, A.V., Bassok, A., Kang, M.

Keywords:
Transit stop amenities, Transit neighborhood, Disaggregate, Crime data, Transit transaction data


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Hallenbeck, M.E. FHWA-JPQ-18-694 I-35 Freight Advanced Traveler Information System (FRATIS) Impacts Assessment 2018 TRAC/UW
Abstract:
Under the Dynamic Mobility Applications (DMA) Program, the U.S. Department of Transportation (U.S. DOT) has sponsored the development of the Freight Advanced Traveler Information System (FRATIS) bundle, which seeks to transform freight mobility by leveraging a system of “connected vehicles” and mobile devices to maximize freight flow. The TxDOT I-35 Traveler Information During Construction (TIDC) system has been enhanced to help maximize freight operators’ productivity, improve operational efficiency, and reduce safety related incidents, by providing freight traveler information such as pre-construction closure notifications, delay predictions, and near real-time construction delay information. The report evaluates the benefits of the delivery of the TIDC’s information to the trucking firms using the system. It is based on a year-long before/after analysis of two major trucking firms, with six months of data collected before the firms started using TIDC information, and six months of after data collection after TIDC information started being used by the companies. At the conclusion of the project, both participating trucking firms remain enthusiastic supporters of the TIDC and are seeking internal company resources for improving the ability of their companies to ingest TIDC data into their existing business processes, however, no quantifiable change in trucking performance was observed. Reasons for the lack of measurable benefit include the limited opportunity to route around the I-35 construction delays, and the lack of automated ingest of TIDC data into the trucking firms’ business systems.

Authors:
Hallenbeck, M.E., McCormack, E.D., Zyuzin, D., Ishimaru, J., Jensen, M., Campbell, R., Chu, A.

Keywords:
Freight advanced traveler information, FRATIS, traveler information, during construction, TIDC, I-35, Texas, before/after analysis


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Shi, X. WA-RD 883.1 Bio-Based Renewable Additives for Anti-Icing Applications (Phase II) 2018 TRAC/WSU
Abstract:
The performance and impacts of several agro-based anti-icers along with a traditional chloride-based anti-icer (salt brine) were evaluated. A statistical design of experiments (central composite design) was employed for developing anti-icing liquids consisting of cost-competitive chemicals such as agro-based compounds (e.g., Concord grape extract and glycerin), sodium chloride, sodium metasilicate, and sodium formate. The following experimentally obtained parameters were examined as a function of the formulation design: ice-melting capacity at 25°F (−3.9°C), splitting strength of Portland cement mortar samples after 10 freeze-thaw/deicer cycles, corrosion rate of C1010 carbon steel after 24-hour immersion, and impact on asphalt binder stiffness and m-value. One viable formula (“best performer”) was tested for thermal properties by measuring its differential scanning calorimetry (DSC) thermograms, the friction coefficient of asphalt pavement treated by this anti-icing formulation (vs. 23 wt.% NaCl and beet juice blend) at 25°F after being applied at 30 gallons per lane mile (1 hour after simulated trafficking and plowing), and other properties (pH, oxygen demand in COD). Laboratory data shed light on the selection and formulation of innovative agro-based snow-and ice-control chemicals that can significantly reduce the costs of winter maintenance operations.

Authors:
Shi, X., Nazari, M.H., Oh, T, Ewing, A.C., Okon, D.A., Zhang, Y., Avalos, B., Alnuaimi, E., Havens, E.A.

Keywords:
Agro-based anti-icer, ice-melting performance, Portland cement mortar, splitting strength, asphalt binder, stiffness, m-value, corrosivity, DSC, friction coefficient, COD


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Ban,X. WA-RD 892.1 Promises of Data from Emerging Technologies for Transportation Applications: Puget Sound Region Case Study 2018 TRAC/UW
Abstract:
With the explosion of the number of studies using big, passively-generated data for transportation analysis, this study focuses on understanding the properties of such data and how these properties affect our ability in deriving trip-related characteristics. Two big data sets were analyzed: a mobile phone data generated primarily on phone calls with locations identified through cellular triangulation and an app-based data generated primarily on app usage with locations identified through a mix of positioning technologies including GPS and cellular triangulation. Both data sets were compared against their household travel survey counterparts. It is shown that the two data sets, generated through different positioning technologies and usage mechanisms clearly have different spatial and temporal characteristics, which then affect trip related attributes such as trip rates and OD patterns. Implications in planning applications and future work are discussed.

Authors:
Ban,X., Chen,C., Wang,F., Wang,J., Zhang,Y.

Keywords:
Big data, mobile phone data, app-based data, travel surveys, travel patterns, origin-destination demand matrices


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Nassiri, S. Evaluation of Motorcyclists\\\' and Bikers\\\' Safety on Wet Pavement Markings 2018 PacTrans
Abstract:
In this study, three different pavement marking material types were evaluated by using a British Pendulum Tester (BPT) in dry, wet, and icy conditions. The frictional properties were recorded as a British Pendulum Number (BPN). Two different rubber sliders on the BPN were used to compare different pavement marking users: a pedestrian slip rubber (PSR) and tire slip rubber (TSR). This study included both laboratory and field testing. The pavement markings evaluated were chosen after a careful review of Washington State Department of Transportation’s specifications and Washington State University’s (WSU) Facilities Services common practices. During laboratory testing, a neat concrete slab surface was compared to waterborne paint, preformed fused thermoplastic, and cold applied pre-formed tape surfaces. Each of the surface types was evaluated under dry, wet, and icy conditions. Laboratory test results showed that the paint and thermoplastics resulted in lower BPN values than the neat concrete surface. However, the centerline striping that was tested did show higher frictional properties than the neat concrete surface because of the contours and surface macrotexture of the tested striping. During field testing, two locations on the WSU Pullman campus were chosen for testing in dry and wet conditions. Each location was evaluated by using the BPT, and then two bicyclists rode over the markings in a variety of ways in dry and wet conditions. The tested locations were painted markings. A safety scale was created for riders to evaluate the field markings. The results showed that riders generally felt safe while riding in a straight line over the pavement markings. Most of the unsafe ratings occurred during wet testing, and as cyclists turned and braked over the pavement markings. In comparing the laboratory and field testing BPN values, the laboratory values were typically higher. This was most likely due to the fact that beads were present on the laboratory markings and not on the field markings. From these results, the authors concluded that centerline striping showed the most promising frictional properties. Although paint and thermoplastics showed lower frictional properties than those of the neat concrete surface, the use of beads helped improve the laboratory values over the field testing values.

Authors:
Nassiri, S.

Keywords:
Friction, pavement marking, skid resistance, paint, thermoplastic


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Hernandez, S. Confounding Factors of Commercial Motor Vehicles in Safety Critical Events 2018 PacTrans
Abstract:
Recent quasi-experimental commercial motor vehicle (CMV) driver hours-of-service (HOS) studies published through the Federal Motor Carrier Safety Administration (FMCSA) in 2011 readily identified consistent increases in crash odds as driving time increased. These studies identified time-on-task as a significant indicator of the potential for a safety critical event (SCE) (crash, near crash, or crash-relevant event). However, while these studies may have provided indication of a relationship between HOS and the probability of an SCE, they largely failed to account for many potential confounding factors. The HOS relationship is frequently attributable to the fatigue of the driver. Confounding factors however, are those factors that may also contribute to the likelihood of an incident and potentially create a systematic bias or contribute to measured error. This study sought to uncover existing relationships between the HOS observations and a set of potential confounding factors related to time of day. These relationships were addressed by controlling for confounds. Conclusions drawn from HOS-related studies, such as those mentioned herein affect millions of people and have economic impacts in the billions. Faulty scientific inferences from these studies can have high human and economic costs. Therefore, the work described in this study was needed to validate the findings of these studies, as well as other studies using similar designs and variables. In addition, the work described could lead to deeper insights into commercial motor vehicle crash risk and causation, with safety implications and applications beyond HOS regulations. We foresee the following to benefit from this work: federal regulators, trucking industry groups, carriers, academia, insurance companies; anyone interested in understanding crash causation.

Authors:
Hernandez, S., Al-Bdairi, N.S.S., Jessup, E.L.

Keywords:
Commercial motor vehicle, driver hours of service, fatigue, incidents, crash risk


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Hajbabaie, A. WA-RD 809.1 Safety and Operations Assessment of Various Left-Turn Phasing Strategies 2018 PacTrans
Abstract:
This research evaluates the safety and operational impacts of different left turn movement treatments at signalized intersections. The project (1) compares safety and operational impacts of Protected-Only Left-Turn (POLT) phase against Protected-Permissive Left-Turn (PPLT) phase with a Flashing Yellow Arrow (FYA) indication, (2) compares safety and operational impacts of doghouse display against four section vertical display for PPLT with a Flashing Yellow Arrow, (3) and identifies if time-of-day (TOD) variable left-turn control mode with FYA induces confusion among left-turning drivers. Literature shows that converting a POLT to a PPLT control mode is associated with an increase in crash rates while reducing intersection delay. Previous research recommended to select the control mode considering traffic volume, speed limit, sight distance, number of lanes, and crash history. Previous research shows that doghouse displays are associated with larger crash modification factors, more confusion among drivers, and higher delays compared to a four-section vertical display with an FYA. The results of our driver comprehension survey showed that half of the drivers who have encountered intersections with variable left turn control mode by TOD felt confused of such phasing strategy. On the other hand, the simulation-based analysis showed that changing the left turn control mode by TOD yields more efficient traffic operations and lower average delays.

Authors:
Hajbabaie, A., Sattarov, S., Mohebifard, R.

Keywords:
Safety, traffic operations, left-turn, protected, protected permissive, permissive, time of day, simulation


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Roeder, C. WA-RD 776.2 Shear Design Expressions for Concrete Filled Steel Tubes and Reinforced Concrete Filled Tube Components 2017 TRAC/UW
Abstract:
Concrete-filled steel tubes (CFSTs) and reinforced concrete-filled steel tubes (RCFSTs) are increasingly used in transportation structures as piers, piles, caissons or other foundation components. While the axial and flexural properties of CFTs have been well researched, research on their shear resistance is lacking. Currently accepted methods for calculating the shear capacity of CFSTs and RCFTs are adapted from shear strength equations used for structural steel or reinforced concrete components. Though, it is expected that CFSTs would retain the full shear capacity of the steel without local buckling of the section. In addition, because circular CFSTs provide optimum confinement to the concrete core, it is also expected that the full shear strength of plain or longitudinally reinforced concrete can also be developed. Since no equation currently accounts for both, it is probable that they significantly underestimate the effectiveness of the composite section, potentially increasing undesirable conservatism and cost. However, without experimental data to validate the design expressions, it is not possible to modify them. The research program described herein experimentally investigated the shear resistance and deformation of CFST and RCFST members with an eye towards developing an improved and more accurate shear strength expression. The experimental study included 22 large-scale CFTs subjected to four-point bending. The study parameters included: (1) the aspect ratio (a/D where a is the clear span from the point of loading to the point of support and D is the tube diameter), (2) concrete strength, (3) D/t (where t is the thickness of the steel tube), (4) interface condition (greased or contaminated with soil), (5) infill type (concrete or gravel), (6) internal reinforcement ratio, and (6) length of the tube beyond the support (tail length). The results indicate that the shear strength of CFSTs and RCFSTs is on average 2 times the current WSDOT expression. This new design expression for shear resistance has been proposed for implementation in the WSDOT Bridge Design Manual (BDM).

Authors:
Roeder, C., Lehman, D., Heid, A., Maki, T.

Keywords:
concrete filled steel tubes, CFST, RCFST, shear resistance


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Hallenbeck, M.E. WA-RD 864.1 Review of Travel Data Collection and Analysis Process for Delay Calculations Statewide 2017 TRAC/UW
Abstract:
WSDOT produces and uses estimates of vehicle delay on state highways throughout the state. Large swings in delay computed on some roads and in some corridors by the current statewide delay process resulted in the decision to review the performance of that system. As a result, this project was undertaken to examine the causes of these wide swings in reported delay and to determine possible courses of action for WSDOT. The project reviewed the software used to produce those delay estimates, the input data sets used in those computations, and the steps followed to generate those data sets. This report recommends changes to the delay computation process. The report describes several different approaches that could be adopted by WSDOT to compute vehicle delay. It makes recommendations for WSDOT’s consideration. The best option is a function of the funding available to WSDOT and the other uses for the data needed to drive each of those various approaches to delay computation.

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

Keywords:
Performance measures, Roadway performance measures


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Dahl, P.H. WA-RD 861.2 Measurements of Pile Driving Noise from Control Piles and Noise-Reduced Piles at the Vashon Island Ferry Dock 2017 TRAC/UW
Abstract:
As the part of the Washington State Department of Transportation (WSDOT) pile attenuation test program, researchers from the University of Washington Applied Physics Laboratory (APL-UW) conducted underwater sound measurements on 7 and 8 December 2015 at the Vashon Island ferry dock. A WSDOT team operating closer to the construction barge also took measurements. The goals of the APL-UW team were to measure the underwater sound field over nearly the entire water column and away from interfering structures, as well as to make robust estimates of sound mitigation performance of two test pile designs in terms of sound exposure level (SEL) and peak pressure. Measurements on the R/V Robertson were taken at a range of 120 m from the construction barge complex and pile source location and at a water depth 12.5 m by using a vertical line array (VLA) that spanned 1.25 to 9.25 m in depth. A comparison of the 7 December measurements from the double wall test pile with the control pile showed reductions in peak pressure (8.7–13.5 dB), RMS pressure (8.8–12.7 dB), and SEL (7–10.3 dB). A comparison of the 8 December measurements from the mandrel test pile with the 7 December measurements from the control pile showed reductions in peak pressure (11.4–14 dB), RMS pressure (10.8–12.6 dB), and SEL (9.3 and 11.1 dB). The reduction in peak pressure generally increased as measurement depth on the VLA increased; for the RMS and SEL metrics, no trend was observed.

Authors:
Dahl, P.H., Dall'Osto, D.R., Laughlin, J.

Keywords:
Impact pile driving, Underwater sound, Sound mitigation, Attenuation, Sound exposure level (SEL),


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Muhunthan, B. WA-RD 865.1 Liquefaction-Induced Downdrag on Drilled Shafts 2017 TRAC/WSU
Abstract:
Sandy soil layers reduce in volume during and following liquefaction. The downward relative movement of the overlying soil layers around drilled shafts induces shear stress along the shaft and changes the axial load distribution. Depending on the site conditions, the change in the axial responses that result from liquefaction-induced settlement and the drag load can have a significant impact on the performance of drilled shafts in seismic regions. This study presents an analytical method to quantify the effects of liquefaction-induced downdrag on drilled shafts. The analytical method is based on the neutral plane method originally developed for clays but modified to account for liquefaction-induced effects. The neutral plane method is a simplification of soil-shaft interactions and is more representative of actual conditions than other methods. In this study, the neutral plane method was applied to an observed case of downdrag during the 8.8 magnitude earthquake in Maule, Chile, and was able to predict the liquefaction-induced settlement that was the major cause of failure of the structure. The developed procedure is illustrated for two field cases of drilled shafts in liquefiable soils in Washington state.

Authors:
Muhunthan, B., Vijayathasan, N.V., Abbasi, B.

Keywords:
Axial loads, liquefaction-induced settlement, sand, seismic analysis, side resistance, soil liquefaction, soil settlement, drilled shafts


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Nassiri, S. WA-RD 868.1 Preliminary Study to Develop Standard Acceptance Tests for Pervious Concrete 2017 TRAC/WSU
Abstract:
Pervious concrete pavements are permeable pavement systems that are desired for their role in stormwater management and runoff control. Increased popularity in pervious concrete pavement applications has increased the need for the development of quality control and quality-evaluation test procedures that are better suited to pervious concrete than to traditional concrete. This brief study took a few preliminary steps in that direction by investigating the effects of specimen size on the physical properties of pervious concrete, such as hardened porosity and density, as well as compressive strength. Moreover, the study investigated the effects of four different curing regimens combined with air and moist curing over a four-week period on the 28-day compressive strength for two specimen sizes.

Authors:
Nassiri, S., Rangelov, M., Chen, Z.

Keywords:
Pervious concrete, porosity, infiltration, compressive strength, curing


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Moudon, A.V. WA-RD 862.1 Safe Main Street Highways Part I: Washington State Collision Data and Geocoding 2017 TRAC/UW
Abstract:
This project contributes to the Washington State Strategic Highway Safety Plan, whose goals are to achieve zero road fatality and serious injury by 2030 and to reduce the number of pedestrians and bicyclists involved in motor-vehicle collisions on state highways. The study focused on “main street highways” (MSHs), which are stretches of State Routes that also act as main streets for the local populations. This report covers Part I of this study, which collected an inventory of collision data in Washington state from 2001 to 2012. The project tallied those collisions that had been geocoded, and the report describes the various methods used for geocoding. More than 90 percent of the collisions had been geocoded for 2010, 2011, and 2012, but only pedestrian and bicyclist collisions had been geocoded for the years between 2001 and 2009.

Authors:
Moudon, A.V., Kang, M.

Keywords:
Washington state collisions inventory, Inventory of geocoded collisions , Geocoding methods


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Moudon, A.V. WA-RD 862.2 Safe Main Street Highways Part II: Analyses of Collisions Involving Pedestrians and Bicyclists in Washington State 2017 TRAC/UW
Abstract:
This project contributes to the Washington State Strategic Highway Safety Plan, whose goals are to achieve zero road fatality and serious injury by 2030 and to reduce the number of pedestrians and bicyclists involved in motor-vehicle collisions on state highways. The study focused on “main street highways” (MSHs), which are stretches of State Routes that also act as main streets for the local populations. This report covers Part II of the study, which (1) identified hotspots of pedestrian and bicyclist collisions, and (2) developed models for estimating socio-economic and environmental predictors of collision locations. Collision hotspots were derived from Planar and novel Network Kernel Density Estimation (KDE) methods. Case-control and negative binomial models showed that high risk pedestrian and bicyclist collision locations were significantly associated with collisions occurring (1) at street and road intersections (versus mid-blocks); (2) on wider roads; (3) on roads with bicycle lanes; (4) in low income and non-white neighborhoods.

Authors:
Moudon, A.V., Kang, M.

Keywords:
Pedestrian safety, Bicyclist safety, Hotspot detection , Collision risk at intersections, Built environment, Geographic information system


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Hallenbeck, M.E. WA-RD 863.1 Use of Electronic Fare Transaction Data for Corridor Planning 2017 TRAC/UW
Abstract:
This report documents the initial phase of a project that developed, tested, and used a methodology and tool set for converting electronic transit agency fare card transaction data, the Puget Sound region’s ORCA electronic fare card, into information that describes how customers are using the transit system. The project used two nine week datasets. The first covers February 17, 2015, to April 14, 2015. The second covers from March 26, 2016, to May 27, 2016. The report describes the detailed steps necessary to combine ORCA transaction data with vehicle location data and other data sources in order to estimate ridership patterns and other information useful for transit planning and operational needs. Data provided includes origin/destination matrices by day-of-week, and time-of-day, transfer locations, and transfer details such as the distances walked in order to transfer and the time required to make those transfers. The detailed data processing flow is described. Also included is a detailed discussion of data privacy concerns, how those concerns were addressed in this project, and how they might be addressed as part of an ongoing business intelligence system. The report also illustrates a wide variety of uses for these types of data.

Authors:
Hallenbeck, M.E., Howard, E., Zyuzin, D., Avery, R., Verma, M.

Keywords:
Electronic transit fare card data, transit planning data


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Qiao,P. WA-RD 870.1 Best Practices of Using Shotcrete for Wall Fascia and Slope Stabilization (Phase I Study) 2017 TRAC/WSU
Abstract:
Shotcrete has become attractive and holds potential to replace cast-in-place (CIP) concrete for elements like retaining walls and slope stabilization. However, this practice is still limited due to concerns of drying shrinkage cracking, long-term durability, and debonding from reinforcing bars or existing structures. To provide best practices of shotcrete for wall fascia and slope stabilization, a comprehensive review on the state of knowledge of shotcrete is first provided. A desirable shotcrete mixture and a CIP concrete mixture from WSDOT benchmarks are tested for their basic mechanical properties, early age shrinkage, and long-term durability performance. The restrained ring test procedures adopted from AASHTO T334 are identified to be capable of evaluating early- age shrinkage cracking tendency of shotcrete, and the fracture energy test procedures based on three-point bending beam are considered to be more sensitive than the dynamic modulus of elasticity test in screening degradation effect of materials under rapidly repeated freezing and thawing action. Prolonged watering provide best practices to mitigate shrinkage cracking. In comparison with CIP concrete, the “before shooting” shotcrete mixture studied in Phase I exhibits better early age shrinkage resistance as well as long-term freeze-thaw resistance. The Phase II study will be conducted for evaluating “after shooting” shotcrete and their early age shrinkage and long term durability performance.

Authors:
Qiao,P., Zhou,Z.

Keywords:
Shotcrete, CIP concrete, prolonged watering, free shrinkage, restrained shrinkage, freeze-thaw, durability, dynamic modulus, fracture energy


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Hallenbeck, M.E. WA-RD 873.1 Implementing the Routine Computation and Use of Roadway Performance Measures within WSDOT 2017 TRAC/UW
Abstract:
The Washington State Department of Transportation (WSDOT) is one of the nation’s leaders in calculating and using reliability statistics for urban freeways. The Department currently uses reliability measures for decision making for urban freeways—where it has applicable data—and as input to analyses that are part of major investment studies and other project identification and prioritization studies. The project documented in this report is intended to provide WSDOT with an online data analytics system that is capable of producing a variety of roadway performance measures specifically oriented toward identifying bottlenecks, and of determining the size, timing, and scope of delays those bottlenecks impose on travelers and freight shipments. The data used to determine the size of delays are also to be accessible as inputs to tools designed to evaluate alternative strategies for improving roadway performance. The system, Digital Roadway Interactive Visualization and Evaluation Network (DRIVE Net), which continues to be developed at the STAR Lab, is designed to integrate data from multiple, siloed data sets. It is intended to create key inputs for WSDOT’s planning and project selection process, as well as supply inputs to other analytical tools used in the planning and programming processes.

Authors:
Hallenbeck, M.E., Ishimaru, J., Cui, Z., Wang, Y., Zhang, W., Hendrickson, K.

Keywords:
SHRP2, travel time reliability, roadway performance monitoring


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Arduino, P. WA-RD 874.1 Numerical Evaluation of Forces on Piled Bridge Foundations in Laterally Spreading Soil [Caution: 20MB file] 2017 TRAC/UW
Abstract:
The response of piled bridge foundations to liquefaction-induced lateral soil deformation is an important design consideration in seismically active regions. Recent research and case history data suggest that three-dimensional deformation of the approach embankment can significantly influence the loads placed on the embedded foundations during a flow failure or lateral spreading event. For example, the 2010 Maule earthquake in Chile caused widespread lateral spreading in the soil surrounding the Mataquito River bridge; however, only insignificant structural damage was observed in the bridge itself. The discrepancy between the amount of soil deformation and structural damage suggests that design procedures for this load case that do not make adequate consideration for 3-D soil deformation mechanisms may lead to overly conservative and expensive design solutions. In contrast, observed lateral spreading and damage near the Llacolén bridge was more relevant and resulted in the collapse of one of the approach sections. The Llacolén bridge approaches showed less 3-D effects on both sides of the bridge and therefore larger loads on the structural components. In this project, finite element models of the Mataquito River and Llacolén bridges were created with the OpenSees computational framework to investigate possible reduction in foundation loads during lateral spreading, as implied by the observed structural damage at the example sites. These models included beam on nonlinear Winkler foundation models, dynamic effective stress models of the bridge-foundation-soil system in plane strain, and 3-D models of the bridge abutments, approach embankments, and surrounding soils. This numerical work sought to frame load reduction mechanisms in the context of a simplified analysis procedure for the lateral spreading load case. The results of the numerical models for the Mataquito and Llacolén bridges, along with a preliminary parameter study conducted with an independent set of 3-D finite element models, indicated that consideration for the 3-D geometry of the bridge site and structure may result in tangible reductions in foundation bending demands and abutment displacements in comparison to those returned by a plane strain description of the problem or simplified analysis using 1-D models. This analysis procedure was modified to better consider the findings of this work, and it is recommended for use in the design of bridge foundations subjected to lateral spreading. Finally, the report proposes an approach to estimate the reductions in abutment displacement and associated foundation bending demands for a given site geometry. The latter is based on results from a preliminary parametric study and requires further development and validation for use in practice.

Authors:
Arduino, P., McGann, C.R., Ghofrani, A.

Keywords:
Lateral spreading, deep foundations, drilled shafts, soil liquefaction, lateral loads, liquefaction-induced lateral displacements,


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Qiao, P. WA-RD 869.1 Developing Connections for Longitudinal Joints between Deck Bulb Tees—Development of UHPC Mixes with Local Materials 2017 TRAC/WSU
Abstract:
In past decades, many state departments of transportation and the Federal Highway Administration (FHWA) have begun working with ultra-high performance concrete (UHPC), an advanced cementitious material. WSDOT has not employed UHPC in highway bridge applications, such as connection joints for precast concrete decks and girders, because of its high cost and lack of experience with it. In this study, two viable mixtures (A4 and C3) were selected from an array of trial UHPC mixtures produced with local materials (primarily local fine sand and domestic steel fiber) for extensive performance evaluation. Researchers investigated the physical and mechanical properties (including workability, compressive and tensile strength, elastic modulus, and shrinkage) of selected UHPC mixtures and their bond properties with epoxy-coated reinforcing bars. The two considered mix designs exhibited compressive strength of up to 16 ksi, direct tensile strength of 1.1 ksi, elastic modulus of 5,000 ksi, and relatively high bond strength. Shrinkage was also characterized and was found to be comparable to that of conventional concrete. On the basis of the comparisons of the two selected mixtures' material properties and bond strength, the C3 mixture outperformed the A4 mixture and was therefore recommended for use in the second phase of the project, structural-level testing and evaluation at the University of Washington.

Authors:
Qiao, P., Zhou, Z., Allena, S.

Keywords:
Ultra-high performance concrete, UHPC, connection joints, mix design, mechanical characterization, tensile behavior, pull-out behavior


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Nassiri, S. WA-RD 868.2 Preliminary Procedure for Structural Design of Pervious Concrete Pavements 2017 TRAC/WSU
Abstract:
Pervious concrete (PC) is a pavement material that provides a porous medium to facilitate the infiltration of stormwater to the underlayers. With the increasing use of PC pavement nationwide, the mechanical properties of the material need to be established. To do so, PC specimens of two aggregate types were prepared in various porosities. Hardened porosity, compressive, and flexural strength tests were conducted for all PC specimens. The test results from this study were supplemented by results from past research studies conducted at Washington State University, as well as those from the literature to develop multi-variable linear regression models to predict strength properties for pavement thickness design. The researchers established multi-variable linear regression relationships between the PC compressive and flexural strength, hardened porosity, and mixture design parameters. Additionally, they developed a recommended thickness design database for low-traffic-volume PC pavements with different mechanical properties and under various traffic volumes and axle load configurations. The fatigue model for conventional Portland cement concrete was used to obtain the maximum allowable load repetitions for PC slabs with three different moduli of rupture. To obtain the fatigue life of PC, four traffic categories and axle loads were obtained from the American Concrete Institute’s (ACI) guide on the design of concrete parking lots. The applied stress of each axle load on PC slabs was obtained by using a previously validated finite element model. Using the applied stress and different flexural strength values of PC, the researchers generated the fatigue life of PC slabs with various thicknesses and mechanical properties. On the basis of the calculated fatigue life and the traffic volumes specified by the ACI, the researchers developed a thickness design table. The proposed thickness design table should be updated by using a fatigue model for pervious concrete.

Authors:
Nassiri, S., Al Shareedah, O.

Keywords:
Pervious concrete, porosity, compressive strength, flexural strength, pavement design, pavement thickness


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Peruchini, T.J. WA-RD 869.2 Investigation of Ultra-High Performance Concrete for Longitudinal Joints in Deck Bulb Tee Bridge Girders 2017 TRAC/UW
Abstract:
In recent decades, many state DOTs have implemented ultra-high performance concrete (UHPC) in bridge construction because of its mechanical properties are advanced beyond those of conventional concrete. The Federal Highway Administration (FHWA) has extensively tested a proprietary class of UHPC, but WSDOT has been hesitant to adopt this mix because of its high cost and associated high risk. In this study, a mix design developed by Washington State University was tested for its structural performance when used in a reinforced spliced connection between adjacent concrete deck-bulb tee (DBT) bridge decks. The important parameters for this application are the bond strength of epoxy-coated reinforcing bars to the UHPC, as well as the tension strength of the UHPC when the rebar in the connection is stressed axially in tension. ASTM-standard test procedures in this study showed that compressive strengths of up to 16 ksi, tension strengths of above 2 ksi, and bond strengths of up to 7 ksi can be achieved with this particular UHPC, all with improved ductility beyond that of conventional concrete, largely because of the steel fiber reinforcements. Structural experiments were performed on idealized “bond curbs” as well as a section of deck representing actual DBT girders to determine the available bond strength and the corresponding required joint width. These experiments and the subsequent analysis showed that a UHPC joint width of 7.11 inches, corresponding to a splice length of 5.11 inches, is satisfactory to fracture the reinforcement within the connection. To account for construction tolerances, this joint width should, in practice, be increased to 10 inches.

Authors:
Peruchini, T.J., Stanton, J., Calvi, P.

Keywords:
Ultra-high performance concrete (UHPC), longitudinal joints, mechanical characterization, tensile behavior, bond behavior, deck bulb tees


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Arduino, P. WA-RD 874.2 Design Procedure for Bridge Foundations Subject to Liquefaction-Induced Lateral Spreading 2017 TRAC/UW
Abstract:
The response of piled bridge foundations to liquefaction-induced lateral soil deformation is an important design consideration in seismically active regions. Recent research and case history data suggest that three-dimensional deformation of the approach embankment can significantly influence the loads placed on the embedded foundations during a flow failure or lateral spreading event. For example, the 2010 Maule earthquake in Chile caused widespread lateral spreading in the soil surrounding the Mataquito River bridge, however, only insignificant structural damage was observed in the bridge itself. The discrepancy between the amount of soil deformation and structural damage suggests that design procedures for this load case that do not make adequate consideration for 3D soil deformation mechanisms may lead to overly conservative and expensive design solutions. In contrast, observed lateral spreading and damage near the Llacolén bridge was more relevant and resulted in the collapse of one of the approach sections. The Llacolén bridge approaches show lesser 3D effects on both sides of the bridge and therefore larger loads on the structural components. In this work, finite element models of the Mataquito River and Llacolén bridges are created using the OpenSees computational framework to investigate possible reduction in foundation loads during lateral spreading implied by the observed structural damage at the sites. These models include beam on nonlinear Winkler foundation models, dynamic effective stress models of the bridge-foundation-soil system in plane strain, and 3D models of the bridge abutments, approach embankments, and surrounding soils. This numerical work seeks to frame load reduction mechanisms in the context of a simplified analysis procedure for the lateral spreading load case. The results of the numerical models for the Mataquito and Llacolén bridges, along with a preliminary parameter study conducted using an independent set of 3D finite element models, indicate that consideration for the 3D geometry of the bridge site and structure may result in tangible reductions in foundation bending demands and abutment displacements compared to those returned by a plane strain description of the problem or simplified analysis using 1D models. This analysis procedure is modified to better consider the findings of this work and it is recommended to use in the design of bridge foundations subjected to lateral spreading. Finally, an approach is proposed to estimate the reductions in abutment displacement and associated foundation bending demands for a given site geometry. The latter is based on results from a preliminary parametric study and would require further development and validation to use in practice.

Authors:
Arduino, P., McGann, C., Ghofrani, A.

Keywords:
Lateral spreading, deep foundations, drilled shafts, soil liquefaction, lateral loads, liquefaction-induced lateral displacement


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Chang, K. Safety Data Management and Analysis: Addressing the Continuing Education Needs for the Pacific Northwest 2017 PacTrans
Abstract:
Recent advancements in data collection capabilities have allowed transportation-related agencies to collect mountains of safety data. There is an immediate need to find out what types of safety data are being collected, what types of safety analysis can be done with the collected data, and what (other) types of safety data and analysis approaches are required to meet safety objectives. With the increased complexity of various safety data management and analysis activities, and with most transportation agencies faced with limited staff and financial resources, there is opportunity to provide the transportation workforce, which includes practitioners and academicians alike, with the resources needed to effectively understand, manage, and analyze safety data. Safety data collection, management, integration, improvement, and analysis activities are integral to developing a robust data program that leads to more informed decision making, better targeted safety investments, and overall improved safety outcomes. This project responds to the current gaps in research and identifies a methodology that will benefit all system users. The objectives included developing a comprehensive understanding of needs and priorities with regard to safety data management and analysis; developing a set of core skills and knowledge required for safety data management and analysis; providing a comprehensive set of safety data workforce development resources that can easily be accessed for use and distribution; and identifying and utilizing proven delivery pipelines to supplement program outreach efforts and activities in the safety data area.

Authors:
Chang, K., Brown, S., Chen, C., Hajbabaie, A., Perkins, R.

Keywords:
Safety, safety data, workforce development


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Goodchild, A.V. WA-RD 850.1 Food Distribution Supply Chain Data Collection: Supply Chain Firm Interviews and Truck Counts 2016 TRAC/UW
Abstract:
This report summarizes the work completed under the SHRP2 (Strategic Highway Research Program 2) Local Freight Data program. Supply chain firm interviews and truck counts were conducted to better understand the Food Distribution System in the Puget Sound area. Interviews explored key business challenges, operations, and potential responses to natural gas incentives. Truck counts were conducted at grocery stores, and observations included truck type, time of day, stop duration, and parking behavior. The report includes a description of truck activity at grocery stores, and a summary of industry responses to natural gas incentives. The research contributes to the design of future freight data collection and to the development of policy responsive freight models.

Authors:
Goodchild, A.V., Ukrainczyk, L.

Keywords:
Food distribution, freight data collection, truck trip generation, natural gas, Washington state, freight models


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Hallenbeck,M.E. WA-RD 846.1 Evaluation of the Effects of Changing to Continuous Access HOT Lanes on SR 167 2016 TRAC/UW
Abstract:
In August 2014, WSDOT changed the access controls for the HOT lanes on State Route (SR) 167. The lanes were initially designed and implemented to allow access at only six points northbound and four points southbound. Since August 23, 2014, free access has been allowed into and out of the HOT lane. This study was performed to determine the effects of allowing continuous access to the SR 167 HOT lanes. It examined customer attitudes toward the new access rules, the performance of the corridor, including both the HOT lanes and the parallel general purpose (GP) lanes, and the volumes of use and travel times experienced. It also examined the amount of revenue collected, the amount of toll evasion occurring, collision frequency and severity, and the impacts on transit operations. The changes in the corridor since the change in access rules have been complex. This report describes that complexity. In general, traffic volumes are increasing in the corridor. Travel times have degraded slightly in both the GP and HOT lanes in the corridor. Prices and total revenue are up in the HOT lane. Prices increased substantially during the first five months of operation of the new rules, decline somewhat after that, but remain higher than under access control rules. No statistically significant change in safety is apparent. A large fraction of the travelers in the corridor are in favor of the access rule changes, and that includes the transit agencies operating in the corridor.

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

Keywords:
performance measures, roadway performance measures, freight performance measures


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Wang,Y. WA-RD 847.1 Study on Illumination for State Highways 2016 TRAC/UW
Abstract:
Increasing budget pressures are causing the Washington State Department of Transportation (WSDOT) to look for ways to reduce costs. WSDOT currently owns and operates illumination fixtures on state freeways and highways with annual operating costs measured in millions of dollars. Given the pressures to reduce the WSDOT budget, it is important to have a complete understanding of the means available to reduce operating and capital costs with the least negative impact on service, safety and sustainability. There are several ways that the WSDOT can reduce expenditures on illumination. One way is to use more efficient lighting technologies. A second is to operate illumination more judiciously. Another option is to install fewer luminaires, remove superfluous luminaires and consolidate luminaires. Executing these options effectively requires the WSDOT to collect additional information regarding current and near future illumination practices and technologies. A natural way in the process of revising and adapting WSDOT’s illumination standards is examining how the WSDOT standards compare to other state DOTs, utilities, cities, counties and other public entities internationally. Given the work required to revise, publish and promulgate a new illumination standard, it is advisable to examine the current state of practice in illumination standards in order to inform comprehensive updates. Toward that end, a comprehensive review of illumination design standards, LED illumination technologies and illumination control systems is useful for revising illumination standards. To address these aspects of illumination operation and design, a thorough literature review of existing illumination products, illumination control systems, and illumination spectrum technologies is conducted. This report reviewed existing public agency illumination standards domestically and internationally and outlined the difference in designing standards. An overview of existing luminaire technology performance, as well as operational and maintenance characteristics are provided. In addition, available illumination control and spectrum technologies for performance characteristics are summarized. The results of this literature review are useful for design and business case decisions regarding illumination installation, maintenance, and operation.

Authors:
Wang,Y., Zou,Y.

Keywords:
illumination design standard, LED luminaire technology, illumination control technology, illumination spectrum effectiveness


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Reinhall,P.G. WA-RD 861.1 Underwater Noise Reduction of Marine Pile Driving Using a Double Pile: Vashon Ferry Terminal Test 2016 TRAC/UW
Abstract:
Impact pile driving of steel piles in aquatic environments produces extremely high underwater sound levels. To address this problem, a double-walled pile has been developed to decrease the total noise transmitted into the water and substrate. The double-walled pile consists of two concentric steel pipe piles flexibly connected by a special driving shoe, allowing for an air gap between the two tubes. The double-walled pile is driven into the sediment by using traditional equipment that strikes the inner pile only. The air gap between the inner and outer pile and the flexible coupling prevent the radial deformation wave produced by the pile hammer from interacting with the water and the sediment. A second full-scale test of the double-walled pile technology was performed at Vashon Island, Puget Sound, Washington. A potential reduction of the peak pressure in excess of 17dB was observed for the double pile and of 16 dB for the mandrel pile. Root mean square (RMS) levels and cumulative sound exposure levels (SEL) decreased by 13 dB and 12 dB, respectively. Use of the WSDOT Geotechnical Design Manual Pile Driving Formula showed that the pile capacity of the novel piles was comparable to that of a control pile with the same outer diameter. PDA data were also collected from both the inner and outer piles of the mandrel and double piles and will be used to modify current software for predicting drivability and stresses in the piles (WEAP analysis) and for estimating load capacity after driving (CAPWAP analysis).

Authors:
Reinhall,P.G., Hampden,J., Dardis,T.

Keywords:
pile, sound, acoustic, attenuation, marine, pressure, SEL, sediment, Mach wave


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Wang, Y. WA-RD 854.1 Digital Roadway Interactive Visualization and Evaluation Network Applications to WSDOT Operational Data Usage 2016 TRAC/UW
Abstract:
DRIVE Net is a region-wide, Web-based transportation decision support system that adopts digital roadway maps as the base, and provides data layers for integrating and analyzing a variety of data sources (e.g., traffic sensors, incident records). Moreover, DRIVE Net offers a platform for streamlining transportation analysis and decision making, and it serves as a practical tool for visualizing historical observations spatially and temporally. In its current implementation, DRIVE Net demonstrates the potential to be used as a standard tool for incorporating multiple data sets from different fields and as a platform for real-time decision making. In comparison with the previous version, the new DRIVE Net system is now able to handle more complex computational tasks, perform large-scale spatial processing, and support data sharing services to provide a stable and interoperable platform to process, analyze, visualize, and share transportation data. DRIVE Net’s capabilities include generating statistics for WSDOT’s Gray Notebook (GNB), including travel times, throughput productivity, and traffic delay calculations for both general purpose and HOV lanes, each of which are important performance indicators in the WSDOT congestion report. The DRIVE Net system includes robust loop detector data processing and quality control methods to address the data quality issues impacting loop detectors throughout the state. The capabilities of the DRIVE Net system have been expanded to include safety modeling, hotspot identification, and incident induced delay estimation. Specifically, the Safety Performance module includes functions that can be used to obtain traffic incident frequency, apply predictive models to estimate the safety performance of road segments, and visualize and compare observed incident counts and different predictive models. Additionally, a module providing multi-modal data analysis and visualization capabilities was developed as a pilot experiment for integration of heterogeneous data. This module includes pedestrian and bicycle, public transit, park and ride, Car2Go, and ferry data downloading and visualization. DRIVE Net now offers role-based access control, such that access privileges to different functions and data resources can be assigned on a group or individual basis. The new system is able to support more complex analytics and decision support features on a large-scale transportation network, and is expected to be of great practical use for both traffic engineers and researchers. With a modular structure and mature data integration and management framework, DRIVE Net can be expanded in the future to include a variety of additional data resources and analytical capabilities.

Authors:
Wang, Y., Zhang, W., Henrickson, K., Ke, R., Cui, Z.

Keywords:
Freeway performance measurement, WSDOT Gray Notebook, geospatial data fusion, data Quality Control, automatic pedestrian data collection


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Sage, J. WA-RD 853.1 Wheat Supply Chain Data Collection 2016 TRAC/WSU
Abstract:
As the Washington State Department of Transportation’s (WSDOT) interest in developing a statewide freight model has grown, so too has the need to better understand potential responses of major industries to different policy and market scenarios aimed at reducing freight emissions. This research seeks to understand the wheat supply system and its transportation characteristics, as well as potential behavioral responses by wheat suppliers to changes in policy and market conditions, particularly the feasibility of alternative fuel adoption. To accomplish this, the research team has conducted both new interviews within the wheat supply chain actors, as well as identified existing data sources that help broaden the picture of wheat movement. Results suggest that research is needed to better understand and develop both the power generation of alternative fuel engines as well as the logistics of fuel distribution infrastructure. This is particularly evident for rural freight networks that move heavy agricultural or natural resource based products.

Authors:
Sage, J., Casavant, K.

Keywords:
wheat supply chain, alternative fuels, freight


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Haselbach, L. WA-RD 859.1 Assessment of Lube Oil Management and Self-Cleaning Oil Filter Feasibility in WSF Vessels 2016 TRAC/WSU
Abstract:
This research examined the feasibility of using self-cleaning oil filtration systems in the Washington State Ferries (WSF) fleet from a three-pronged perspective: (1) filtration effectiveness, (2) environmental impacts, and (3) cost impacts. A pilot self-cleaning filtration system, which filters oils without using disposable filter cartridges, was installed on one vessel from which to collect data. Filtration effectiveness was analyzed by using oil analysis records and trending the values of oil properties known to be important for lubrication and which indicate oil degradation. Results showed little difference between the standard paper cartridge filtration system currently in wide use and the self-cleaning system. Environmental impacts were analyzed with a life cycle assessment methodology that quantified potential impacts on the basis of expected operation. There were fewer impacts from oil and filter use for the self-cleaning system, but the additional diesel fuel consumed by that system outweighed the benefits for most impact categories. Cost impacts were analyzed with a life cycle cost analysis, which suggested that the standard system would outperform the self-cleaning system in terms of whole life cost (unless the oil lifetime could be increased by more than three-fold), again mostly because of the the self-cleaning system's additional fuel use. Therefore, if expected costs and environmental impacts are major decision points, it appears that a suitable alternative system would need to consume less diesel fuel to be viable. However, the self-cleaning system analyzed in this report would likely decrease risks, such as oil spills during filter handling, and provide operational benefits attributable to reduced expected maintenance. The pilot system was removed following the data collection period, and deployments of self-cleaning filtration systems to other WSF vessels are not expected.

Authors:
Haselbach, L., Langfitt, Q.

Keywords:
Self-cleaning oil filtration, bypass oil filtration oil analysis, life cycle cost analysis, life cycle assessment, lubricating oil, Washington State Ferries


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Wen, H. WA-RD 860.1 Recommendations for Extending Asphalt Pavement Surface Life within Washington State 2016 TRAC/WSU
Abstract:
This study identifies and evaluates hot mix asphalt (HMA) mix design and construction techniques with potential for improving WSDOT pavement surface life. WSDOT pavement failure mechanisms are found to be predominantly cracking. Rutting may reach a failure threshold first in areas with high traffic or studded tire use. A literature review, survey of state DOT practices, case study, WSPMS (Washington State Pavement Management System) data analysis, and limited laboratory testing identified 17 construction and mix design techniques with promise. Of these 17 techniques the use of stone matrix asphalt (SMA) mixtures for high-traffic interstate routes, 3/8-inch nominal maximum aggregate size mixes for medium/low traffic routes and mountain passes, non-Superpave aggregate gradation, reduced N-design gyration levels for Superpave mix design, and warm mix asphalt (WMA) to aid compaction are highly recommended for further investigation and implementation. Other techniques recommended for further investigation and possible implementation are: adoption of a cracking performance test for Superpave mix design; applying a BST within a year of paving to reduce pavement surface aging; specifying the use of Pave IR for mountain pass jobs and cold weather paving; and using steel slag aggregate in situations that call for improved friction and resistance to studded tire wear (i.e., at mountain passes).

Authors:
Wen, H., Muench, S., Chaney, S., Littleton, K., Rydholm, T.

Keywords:
Asphalt pavement, Cracking, Rutting, Climate, Studded tire wear


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Yonge, D. WA-RD 816.3 tate Ferries Terminal Design Manual: Assessment of Copper and Zinc Adsorption to Lignocellulosic Filtration Media Using ... 2016 TRAC/WSU
Abstract:
This report represents the third and final phase of a three-part effort aimed at providing Sustainable Design Guidelines for Washington State Ferry terminals, specifically addressing the efficacy for removal of copper and zinc using a biobased filter media both in laboratory and field conditions. This work supplements previous reports that detail design concepts in implementation of stormwater strategies to be deployed on waterfront structures. The Bainbridge Island ferry terminal staging area was selected as the field test site. A pilot scale adsorption column and submersible weir system was designed and constructed to fit within an existing stormwater vault. Laboratory and field scale continuous flow column studies were performed on raw and torrefied Douglas-fir Crumbles® (Psuedotsuga menziesii), charcoal (also referred to as biochar), and pea gravel to evaluate their effectiveness for adsorbing soluble forms of copper and zinc. Laboratory column tests indicated that the most efficient adsorption for both copper and zinc was non-torrefied wood, followed in order by pea gravel, torrefied wood, and charcoal. Increasing influent column flow by a factor of four resulted in no statistically significant difference in effluent metal concentration. A deicer flush performed on torrefied wood and charcoal columns following adsorption tests resulted in over an order of magnitude increase in column effluent copper and zinc concentration, indicating that bypassing the filtration system during deicer runoff events should be considered.

Authors:
Yonge, D., McIntyre, V., Smith, J., Norgaard, I., Wolcott, M.

Keywords:
Sustainability, ferry terminals,, stormwater, Washington state, runoff, filtration, copper, zinc


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Hallenbeck, M.E. WA-RD 844.1 Developing a System for Computing and Reporting MAP-21 and Other Freight Performance Measures 2015 TRAC/UW
Abstract:
This report documents the use of the National Performance Monitoring Research Data Set (NPMRDS) for the computation of freight performance measures on Interstate highways in Washington state. The report documents the data availability and specific data quality issues identified with NPMRDS. It then describes a recommended initial set of quality assurance tests that are needed before WSDOT begins producing freight performance measures. The report also documents the initial set of performance measures that can be produced with the NPMRDS and the specific steps required to do so. A subset of those metrics was tested using NPMRDS data, including delay and frequency of congestion to illustrate how WSDOT could use the freight performance measures. Finally, recommendations and the next steps that WSDOT needs to take are discussed.

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

Keywords:
Performance measures, Roadway performance measures, Freight performance measures


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Reinhall, P.G. WA-RD 849.1 Underwater Reduction of Marine Pile Driving Using a Double Pile 2015 TRAC/UW
Abstract:
Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. It has been shown that current pile driving noise attenuation techniques, such as bubble curtains and cofferdams, provide limited noise reduction because significant noise is transmitted through the sediment into the water. Similarly, the effectiveness of surrounding the pile in the water with a double walled steel tube was shown in an earlier WSDOT study to be limited. To address this problem, a double walled pile has been developed to decrease the total noise transmitted into the water. The double walled pile consists of two concentric tubes connected by a special driving shoe, with an air gap between the two tubes. The double walled pile is driven into the sediment by using traditional equipment to strike the inner tube only. The air gap between the inner and outer tube prevents the radial deformation wave produced by the pile hammer from interacting with the water and the sediment. This report discusses the design of the double wall pile and presents the results from finite element modeling of the pile, scaled prototype testing, and full-scale field testing in Commencement Bay, Puget Sound, Washington. The tests showed that the double walled piles reduce the peak sound pressure over 20 dB relative to single walled piles at a range of approximately 8 meters. They also showed that, in contrast, only a 3- to 6-dB reduction is obtained when a bubble curtain is used on a full-scale, single walled pile.

Authors:
Reinhall, P.G., Dardis, T., Dahl, P.H.

Keywords:
Pile driving impact, Acoustics, Underwater noise, Attenuation, Propagation


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Muench, S.T. WA-RD 838.1 Determining Changes in Greenhouse Gas Emissions (1990-2010) due to Pavement Technology 2015 TRAC/UW
Abstract:
This research quantifies the changes in greenhouse gas (GHG) emissions and energy consumption from WSDOT between 1990 and 2010 associated with (1) using warm mix asphalt (WMA), reclaimed asphalt pavement (RAP), fly ash, and slag in pavement materials; (2) use of the dowel bar retrofit (DBR) as a portland cement concrete pavement (PCCP) rehabilitation practice; (3) improvements i WSDOT pavement network roughness; and (4) adoption of a long-life asphalt concrete pavement (ACP) strategy. Findings showed the following: Use of WMA, RAP, fly ash, and slag can result in GHG emissions and energy consumption savings of 4-44 percent, depending on the scenario. DBR use can save on the order of 15 percent in GHG emissions and energy consumption if it extends the life of existing PCCP by 15 years. WSDOT's overall pavement network actually got rougher from 1990 to 2010; therefore, no savings associated with GHG emissions or energy consumption were realized. Reducing WSDOT pavement network roughness as a means to reduce GHG emissions may cost on the order of $44/MTCO2e, which is quite expensive by any measure. There was no discernible trend toward long-life asphalt ACP from 1990 to 2010. Therefore, no savings associated with GHG emissions or energy consumption were identified. In context with the GHG emission and energy consumption associated with WSDOT fleet operations and vehicles driving on WSDOT pavement, total savings is on the order of 0.2 to 0.3 percent.

Authors:
Muench, S.T., Caraballo, E.M., Lin, Y.Y.

Keywords:
Greenhouse gas emissions, energy consumption, paving practices, sustainability


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Sage, J. WA-RD 842.1 Washington State Short Line Rail Inventory and Needs Assessment 2015 TRAC/WSU
Abstract:
The recently completed State Rail Plan for the state of Washington identified several key issues facing the state’s rail system. Among these key issues are abandonment, port access and competitive needs of the ports and local production regions, as well as intermodal connectivity. Nearly 2000 miles of rail line had been abandoned in Washington State before the late 1990’s, and another 70 have been abandoned since. Many of these miles included were a result of the Class I railroads stepping away from their less profitable lines. These same actions by the Class I railroads also generated opportunity for the creation of many of the state’s short-line railroads on branch and light density lines. The rail system grew smaller during the 1980s and 1990s, and many of the state short lines were not upgraded to meet the standards and conditions required for modern freight rail load limits (286,000 pounds per car). Further investment is needed should the state or owner seek new or improved operations. This study found that more than 55 percent (740 miles) of all short line miles within Washington are not able to efficiently handle 286,000 pound rail cars. Overcoming this deficiency and bringing the state’s short line system to Class II operating status could require infrastructure investments of approximately $610 million. This need exceeds the current funding support offered by the state, even if considered over a 20 year horizon with private industry and/or local jurisdictions providing significant match. Three short line case studies in this report help identify the societal benefits associated with a functioning short line system within the state’s dynamic transportation network. These case studies, along with information about the attributes that contribute to the success or failure of investments in load centers, illustrate the benefits of state investment in the short line railroad system.

Authors:
Sage, J., Casavant, K., Eustice, J.B.

Keywords:
Short line rail, Freight, Railroad


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Bender, D.A. WA-RD 843.1 Identification of Test Methods for Determining Wood Guardrail Post Integrity 2015 TRAC/WSU
Abstract:
Wood guardrail posts are subject to decay and deterioration, yet most DOTs have minimal or no inspection procedures in place for wood guardrail posts. The objective of this study was to identify nondestructive testing technologies to assess the condition of wood guardrail posts for internal decay. The stress wave timing (SWT) technique was judged most promising, and a prototype device was developed with an industrial partner. The prototype SWT device was validated using wood guardrail posts removed from service. Internal conditions of the posts were accurately detected in 86% of the specimens. The device also successfully detected the internal condition of all posts inspected during a field test. An inspection procedure was recommended for implementation using SWT in conjunction with drilling of posts that identified as suspected decay.

Authors:
Bender, D.A., Olszko, E.

Keywords:
Nondestructive testing (NDT), Nondestructive evaluation (NDE), Stress wave timing (SWT), wood, guardrail


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Flury, Markus WA-RD 848.1 Experimental Evaluation of Compost Leachates 2015 TRAC/WSU
Abstract:
Compost is often used in raingardens, roadsides, and bioretention systems, not only because of its beneficial properties on soil quality, but also because compost improves water infiltration and retains stormwater contaminants. However, when compost is freshly applied, materials from compost can leach out when rain or stormwater seep through compost or compost-amended bioretention media. The goal of this research project was to experimentally evaluate and characterize leachates from compost. We quantified and characterized the leachate composition of compost following intermittent, simulated storm events. We used municipal compost of different ages and different source materials. Compost was filled into columns and then irrigated with deionized water and stormwater. Stormwater was spiked with copper to increase copper concentrations. Six-month, 24-hour rain storms were applied every two weeks for a total of up to 18 rain storms. Outflow was analyzed for pH, electrical conductivity (EC), particulate concentration, surface tension, dissolved organic carbon (DOC), nitrogen, phosphorus, and copper. Particulate and dissolved organic matter was further characterized for molecular structure by Nuclear Magnetic Resonance (NMR) and Fourier-Transformed Infrared (FTIR) Spectroscopy. Our results showed that concentrations of dissolved and particulate organic carbon and electrical conductivity in the leachate where high at the onset of each storm, but decreased as the storm progressed. However, each new storm released another peak of constituents. Leaching from mature compost was less a function of age and type, but more a function of number and frequency of storms and leaching history. Concentrations of nitrogen, phosphorus, and copper were high in the initial few storms, and then decreased. Only a small fraction (3%) of the copper present in the compost leached out, but nonetheless, the copper concentrations in the leachate remained above the regulatory waste discharge standards. NMR and FTIR analyses revealed that dissolved organic carbon consisted mainly of aliphatic and aromatic components typical of fulvic and humic acids. Our results show that municipal compost can serve as a sustained source of leaching of nutrients and metals, regardless of compost age and source. However, the copper concentrations observed in our experiment are likely not toxic due to the presence of elevated DOC, as DOC readily forms complexes with dissolved copper thereby reducing its toxicity to aquatic organisms. The DOC plays a dual role in terms of copper fate and transport: DOC can enhance leaching of copper by forming aqueous complexes, but at the same time, reduces toxicity of copper because copper-DOC complexes are less bioavailable.

Authors:
Flury, Markus, Mullane, Jessica M., Chahal, Maninder K., Cogger, Craig G.

Keywords:
Compost, Leaching, Nitrate, Phosphorus, Copper


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Hallenbeck, M.E. FHWA-JPO-15-216 South Florida Freight Advanced Traveler Information System: Demonstration Team Final Report 2015 FHWA
Abstract:
This Demonstration Team Final Report has been prepared to provide an overview of the conduct and qualitative findings of the South Florida FRATIS development and testing program. More specifically, this document provides a description of the testing program; information and lessons learned related to stakeholder/user engagement during the program; information and lessons learned related to system testing during the program; and recommendations concerning future FRATIS and freight connected vehicle programs.

Authors:
Hallenbeck, M.E., Williamson, M., Kersh, E., Zavagnini, F.

Keywords:
Freight, intermodal, FRATIS, ITS, demonstration


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Cheng, T. WA-RD 810.1 Error Assessment for Emerging Traffic Data collection Devices 2014 TRAC/UW
Abstract:
Because access to travel time information can significantly influence the decision making of both agencies and travelers, accurate and reliable travel time information is increasingly needed.One important step in providing that information is to identify the sensors best suited to provide travel time data for a given corridor. Currently, few studies have evaluated the effectiveness of various travel time data collection technologies side-by-side. This evaluation was intended to provide decision support for transportation agencies looking to select travel time systems on the basis of accuracy, reliability, and cost. This study focused on two test corridors: State Route 522 (SR 522) (an urban arterial with frequent intersections) between the NE 153rd Street and 83rd Place NE intersections, and I-90 (rural freeway built over Snoqualmie Pass in the Cascade mountains) from milepost 109 (Ellensburg, Wash.) to milepost 32 (North Bend, Wash). The sensor systems tested were Washington State Department of Transportation’s pre-existing automatic license plate reader (ALPR) system, Sensys emplacements, the TrafficCast BlueTOAD system, Blip Systems BlipTrack sensors, and a third-party feed from Inrix. This study’s approach was to look at the Mean Absolute Deviation (MAD) to judge the expected magnitude of error, then examine the Mean Percent Error (MPE) to find ant systematic biases in the data. The Mean Absolute Percent Error (MAPE) was useful for finding the relative magnitude of the error, and the Root Mean Square Error (RMSE) was used to determine whether a few large errors or many smaller errors were occurring. Each system in the analysis demonstrated different strengths and weaknesses that should be considered in addition to its accuracy and sample rates. Some systems can provide additional data; others trade accuracy and coverage for cost or portability. Ultimately, engineers will need to weigh their requirements for accuracy and sample rates against the other engineering constraints imposed on their system.

Authors:
Cheng, T., Malinovskiy, A.Y., Corey, J., Namaki, B., Wang, Y.

Keywords:
WSDOT asset management, WSDOT building, asset management processes , case study


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El-Anwar, O. WA-RD 824.1 WSDOT Building Asset Management:  An Exploratory Case Study 2014 TRAC/UW
Abstract:
The mission of the Washington State Department of Transportation (WSDOT) is to keep people and business moving by operating and improving the state’s transportation systems vital to our taxpayers and co mmunities. Traditionally, the Department has focused its efforts on the transportation systems. However, a growing portfolio of transportation assets is burdening an old and often outdated portfolio of building assets that support WSDOT core mission and ho use employees, who design, construct, maintain, and operate state highways. The capacity and condition of these building assets are critical ly challenged by the failure of various building systems, which, when they happen, can be very disruptive or even ha zardous to WSDOT daily operations. Considering the long overdue preservation and replacement of these assets, there is an urgent need to (1) understand how the asset performance influences the various functions that support the Department’s core mission, ( 2) identify the impact of alternative funding levels upon building asset performance, and (3) prioritize the Department’s fundin g decisions in order to fulfill its core mission through a safe and sustainable working environment. This research project is th e first step in a series of potential research projects designed to develop an in - depth understanding of building asset management processes, challenges, and opportunities for WSDOT. This project is an exploratory case study focusing on the Vehicle Repair Shop in the Northwest Region Maintenance Facility in South Seattle. This shop was built in 1954 and is located in a site complex with 33 separate structures, totaling 114,025 SF of space that houses staff and equipment for the maintenance and operation of state highways. The analysis outcomes show that failures occurring at the TEF shop can significantly affect its ability to service the department’s vehicles and equipment. Given the importance of some of these vehicle and equipment in operating the state’s transportation system, failures at the TEF shop can also significantly affect WSDOT\'s ability to fulfill its mission.

Authors:
El-Anwar, O., Migliaccio, G., Lin, K-Y, Gatti, U., Medina, Y.

Keywords:
WSDOT asset management, WSDOT building, asset management processes, case study


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Boyle, L. FHWA-HOP-14-015 Effectiveness of Safety and Public Service Announcement (PSA) Messages on Dynamic Message Signs (DMS) 2014 FHWA
Abstract:
The report assesses the usefulness and effectiveness of safety and public service announcement (PSA) messages through surveys conducted in four urban areas in t he United States: Chicago, IL; Houston, TX; Orlando, FL; and Philadelphia, PA. The surveys were designed to specifically address the types of safety and PSA messages for each respective city. A total of 2 , 088 survey responses were received and analyzed . Th e report further captures findings and recommendations based on the analysis of the survey responses.

Authors:
Boyle, L., Cordahi, G., Grabenstein, K., Madi, M., Miller, E., Silberman, P.

Keywords:
Dynamic message signs, effectiveness, public service announcements, safety, usefulness, transportation management centers


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External Links:
https://ops.fhwa.dot.gov/publications/fhwahop14015/index.htm
Kramer, S.L. WA-RD 827.1 Performance Based Design Factors for Pile Foundations 2014 TRAC/UW
Abstract:
The seismic design of pile foundations is currently performed in a relatively simple, deterministic manner. This report describes the development of a performance-based framework to create seismic designs of pile group foundations that consider all potential levels of loading and their likelihoods of occurrence in a particular area. Because of the multitude of factors that can exist at a site, development of a complete, integrated procedure that would extend from ground motions to limit state excedance was not practical. To make the problem more useful to the research sponsors, a modular approach was developed. The framework allows for the development and use of a structural model with a simplified representation of the foundation system. The discrete soil model was developed using an equivalent linear format so that stiffness and damping characteristics were consistent with deformation levels. The foundation loads computed in these analyses were then applied to a three-dimensional soil-pile group model to compute the resulting displacements and rotations of the pile cap. A computer program was developed to perform the calculations required to develop load and resistance factors and demand and capacity factors. The calculations allow a designer to select a return period for limit state excedance and then select the corresponding factors that will produce a design that corresponds to the desired limit state excedance rate.

Authors:
Kramer, S.L., Valdez, C., Blanchette, B., Baker, J.W.

Keywords:
LRFD, pile foundation, seismic design


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External Links:
http://www.wsdot.wa.gov/research/reports/fullreports/827.1.pdf
Mahoney, J.P. WA-RD 837.1 WSDOT Chip Seals - Optimal Timing, Design and Construction Considerations 2014 TRAC/UW
Abstract:
The Washington State Department of Transportation (WSDOT) does not have sufficient pavement preservation funding to keep up with inflation and pavement needs. This has cause WSDOT to emphasize in its preservation program lower-cost options such as chip seals. The study was conducted on several aspects of WSDOT chip seals including (1) the optimum timing for alternating chip seals (or Bituminous Surface Treatment (BSTs)) with hot mix asphalt (HMA) overlays, (2) design of chip seal application rates, and (3) a range of construction and performance factors. The research incorporated surveys, literature reviews, and five BST meetings that were held between 2006 and 2011. All of these activities are summarized in this report. WSDOT has continuously changed both policy and specifications as new information became available for improving their chip seal performance. In recent years, a policy change resulted in using chip seals on roadways with up to 10,000 ADT. As such, a secondary factor examined in this study was maximum ADT levels which provide for sensible chip seal construction.

Authors:
Mahoney, J.P., Slater, M., Keifenheim, C., Uhlmeyer, J., Moomaw, T., Willoughby, K.

Keywords:
Chip seals, asphalt, ADT, BST, pavement, HMA, inflation, preservation


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Hallenbeck, M.E. WA-RD 832.1 Travel Costs Associated with Flood Closures of State Highways Near Centralia/Chehalis, Washington 2014 TRAC/UW
Abstract:
This report discusses the travel costs associated with the closure of roads in the greater Centralia/Chehalis, Washington, region due to 100-year flood conditions starting on the Chehalis River. The costs were computed for roadway closures on I-5, US 12, and SR 6, and are based on estimated road closure durations supplied by WSDOT. The computed costs are only those directly related to travel that would otherwise have occurred on the roads affected by the flooding closures. The computed costs do not include the economic losses associated with delayed delivery of goods or services, losses in economic activity attributable to travelers being unable to reach their intended destinations, or economic losses associated with the loss of goods because they could not be delivered. The reported costs do include the added costs of time and vehicle mileage associated with available detour routes. Costs were also estimated for each trip that will be abandoned. That is, this study estimated the number of trips that will not be made as a result of road closures. The researchers also conducted a sensitivity analysis of the findings for the I-5 cost computation. Sensitivity tests were conducted for the value of time, the speeds and level of congestion assumed to occur on the routes used for detours, the values associated with trips that are not made via the expected detours, the percentage of personal trips made for work/business purposes versus those being made for personal reasons, the fraction of cars and trucks willing to detour, the effects of flood closure during the weekend or the summer, and growth in traffic volumes on I-5.

Authors:
Hallenbeck, M.E., Goodchild, A., Drescher, J.

Keywords:
Road closure impacts, Flooding traffic impacts, Detour costs


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Hallenbeck, M.E. WA-RD 808.1 Guidelines for Deployment of Future Active Traffic Management Deployment 2014 TRAC/UW
Abstract:
This project tested the prototype software and procedures being developed in conjunction with the SHRP2 L08 project, called FREEVAL-ATDM, for estimating the benefits of improved operations to freeway reliability. That software, a version of the FREEVAL software, computes performance metrics by using algorithms from the 2010 Highway Capacity Manual and new software tools. This report describes the outcome of tests of the use of that software to estimate performance of I-5 in two locations: 1) northbound through Joint Base Ft. Lewis/McCord (JBLM) and 2) northbound approaching downtown Seattle starting just south of the I-405 interchange in Tukwila. The summary conclusions from these tests are that the model can produce the useful outputs for which it was intended, but it tends to under-estimate the travel times and delays actually experienced on the roadway, and it likely needs some additional calibration.

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

Keywords:
ATDM analysis, traffic operations modeling, modeling roadway reliability


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Sage, J. WA-RD 836.1 Truck Freight Commodity Flows: US 395 North of Spokane, Washington 2014 TRAC/WSU
Abstract:
The search for understanding of commodity flows throughout the nation and the State of Washington is a continual process. This understanding is critical at many levels of the transportation industry and to those firms and entities that provide that transportation, or regulate and invest in the needed infrastructure. These data, usually desired at the sub national level, are essential to adequate planning by state, regional and local levels as attempts continue to improve the efficiency, effectiveness and sustainability of the transportation system. State and national travel models require those data, often on a seasonal, commodity/industrial, directional, modal, etc. basis. Determining the importance of a commodity flow on a corridor level leads to the correct prioritization of investments in infrastructure as well as increasing the ability to determine quantitative impacts of congestion, regulation and bottlenecks on a transportation system or supply chain. Using the FPTI (Freight Policy Transportation Institute) developed Intercept Survey Methodology, the research team conducted a series of seasonal truck surveys at three locations on the US 395 corridor between Deer Park and the Canadian Border. Survey results aid in the identification of not only volume and commodity movements in the region, but also bottlenecks and troubled locations identified by the survey respondents.

Authors:
Sage, J., Casavant. K.

Keywords:
Intercept survey, US 395 corridor, freight


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Sage, J. WA-RD 825.1 Freight Commodity Flows: Selected Washington State Highways 2014 TRAC/WSU
Abstract:
The search for understanding of commodity flows throughout the nation and the State of Washington is a continual process. This understanding is critical at many levels of the transportation industry and to those firms and entities that provide that transportation, or regulate and invest in the needed infrastructure. These data, usually desired at the sub national level, are essential to adequate planning by state, regional and local levels as attempts continue to improve the efficiency, effectiveness and sustainability of the transportation system. State and national travel models require those data, often on a seasonal, commodity/industrial, directional, modal, etc. basis. Determining the importance of a commodity flow on a corridor level leads to the correct prioritization of investments in infrastructure as well as increasing the ability to determine quantitative impacts of congestion, regulation and bottlenecks on a transportation system or supply chain. Using the FPTI developed Intercept Survey Methodology, the research team conducted a series of seasonal truck surveys at seven locations: on Snoqualmie Pass (2 sites) and in the greater Wenatchee area (5 sites). Survey results aid in the identification of not only volume and commodity movements in the regions, but also bottlenecks or rerouting options identified by the survey respondents.

Authors:
Sage, J., Casavant. K.

Keywords:
Intercept survey, Snoqualmie Pass, Wenatchee, truck freight


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Poor, C. WA-RD 822.1 Media Filter Drain: Modified Design Evaluation and Existing Design Longevity Evaluation 2014 TRAC/WSU
Abstract:
The media filter drain (MFD), a stormwater water quality treatment best management practice, consists of media made up of aggregate, perlite, gypsum and dolomite in a trench located along roadway shoulders with gravel and vegetative pre-filtering facilities and optional underdrains. One of the many benefits of MFDs is the effective removal of dissolved zinc and copper from roadway runoff. However, the existing design includes use of an aggregate gradation that is no longer readily available (old design). A more readily available and economical aggregate gradation has a slightly lower percent of finer materials (new design). This project evaluates if the new design is as effective as the old design at enhanced dissolved zinc and copper treatment. Findings from laboratory research performed on columns filled with new media versus columns filled with old media indicate that the new media initially has similar removal efficiencies as the old media for large storm events. Accelerated aging of the new media indicates that removal efficiency for dissolved zinc and copper of the new media has not decreased after 15 years of simulated use.

Authors:
Poor, C., Haselbach, L.

Keywords:
Washington state, stormwater treatment best practice, roadway drain filters, highway stormwater treatment design, roadway runoff vegetative pre-filtering and underdrains


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Wang, Y. WA-RD 823.1 Digital Roadway Interactive Visualization and Evaluation Network Applications to WSDOT Operational Data Usage3 2013 TRAC/UW
Abstract:
The combined Washington State Department of Transportation (WSDOT) traffic sensor data and third party data are huge in volume and are highly valuable for system operations, monitoring, and analysis. The current WSDOT traffic data archive systems, however, lack the capability to integrate third party datasets and are not offering the functions needed for real-time performance monitoring, quick operational decision support, and system-wide analysis. The goal of this study was to remove the barriers in the current datasets archived by WSDOT, automate the time- consuming data quality control process, and achieve the integration and visualization of information needed to support decision making. The research findings are not only summarized in this report but are also delivered in a functioning online system named WSDOT Digital Roadway Interactive Vi sualization and Evaluation Ne twork (DRIVE Net). This WSDOT DRIVE Net system is capable of collecting, archiv ing, and quality checking traffic sensor data from all WSDOT regions and incorporating third party data, such as those from INRIX, Inc., and weather information into the analytical platform. Roadway geometric data are properly stored in an open-sourced, geospatial database and are seamlessly connected with the traditional transportation da tasets. The existing WSDOT da ta archiving and analysis systems, CD Analyst and FLOW, are successfully recode d and integrated into the WSDOT DRIVE Net system for better efficiency and consistenc y. A series of loop data quality control algorithms is automated in the backend for detecting malfunction loops and correcting them whenever possible. With the new data platform empowered by eScience transportation principles, two commonly utilized functions at WSDOT have been implemented to demonstr ated the efficiency and utility of this new system. The first is to generate WSDOT’s Gray Notebook statis tics and charts. This new function will allo w WSDOT personnel to produce the tables and figures needed for their annual and quarterly congestion reports in seconds , a significant effi ciency improvement over the months previously necessary. The other function is the Level of Service (LOS) map for highway performance assessment. This module follows the Highway Capacity Manual (HCM) 2010 procedure to produce the LOS estimate for each roadway segment every 20 seconds based on real-tim e traffic measurements. Additionally, a mobile sensing data analysis module was developed as a pilot experiment for reconstructing pedestrian trajectories using the Media Access Control addresses captured from mobile devices. Traffic engineers and researchers can directly access the WSDOT DRIVE Net system through the Internet. The system has demonstrated its ability to support more compli cated analytical and decision procedures for large-scale transportation networks.

Authors:
Wang, Y., Ma, X., Malinovskiy, Y., Corey, J., Henrickson, K.

Keywords:
Freeway performance measurement, WSDOT Gray, Notebook, geospatial data fusion, data quality control, automatic pedestrian data collection


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Moudon, A.V. WA-RD 805.1 Land Development Risks Along State Transportation Corridors 2013 TRAC/UW
Abstract:
Land development that is not coordinated with transportation planning can compromise the performance of Washington\'s state routes.  Identifying land at risk for development along state routes can provide opportunities for proactive, collaborative planning to improve access, mobility, and safety while supporting economic development.  This project, described in two parts, provides tools to help turn adverse risks of land development into opportunities to make route improvements.      In part one, systems for identifying land at risk for development were developed for the state and local levels from relevant literature and expert input.   Risk factors for land development at the state level include historic population and job growth, population and job forecasts, and traffic conditions.  Additional risk factors at the local level include regulatory constraints, critical areas, vacant and undeveloped lands, recent sales history, building permit history, and sewer and water utilities.  the local level system was applied to three case study areas.  Results generally agreed with local knowledge, yet the method offered an objective and systematic means for comparing corridors across the state fairly.      In part two, a menu of strategies for responsibly developing state routes was developed from current WSDOT practices, literature on standard approaches, and reports of novel solutions.  Strategies were classified as planning and coordination activities, non-engineering and engineering strategies, and funding/enforcement strategies.   

Authors:
Moudon, A.V., Sheikh, A., Stewart, O., Kraus, A., Hallenbeck, M.E.

Keywords:
Land development, right of way, risk analysis, transportation planning, corridor planning, forecasting, land use, access management,


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