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

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

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

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/595.1.pdf http://wsdot.wa.gov/Research/Reports/500/595.1.htm

Abstract:
This document presents a plan pile driving research based on the issues and needs of the WSDOT and resource agencies and on discussions that took place during an April 2004 pile driving workshop that was sponsored by WSDOT and coordinated by Battelle. The work plan is designed to meet WSDOT/WSF needs for pile driving research and to further understanding of pile driving impacts to aquatic animals in the Puget Sound.

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

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

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/590.1.pdf http://wsdot.wa.gov/Research/Reports/500/590.1.htm

Abstract:
Cotton duck bearing pads (CDP) are sometimes used to support loads and accommodate movements and rotations at bridge bearings. CDP are preformed elastomeric pads consisting of thin layers of elastomer interlaid with fabric, and they are manufactured under Military Specifications with limited guidance from the AASHTO. The behavior of these CDP bearing pads was experimentally evaluated to establish design models for predicting this behavior, to determine the variation in behavior expected with different bearing pad manufacturers, and to develop design recommendations. This research is a follow-up study of an earlier research program sponsored by Arkansas State University.CDP bearing pads from three different manufacturers were tested, and the test program included dynamic and static (or monotonic) tests of bearings in shear, compression,and rotation. In general, the static tests were used to evaluate strength, stiffness, deformation limits, and general pad behavior. The dynamic tests examined durability and performance under repeated loading and deformation.The results of this test program were used to develop design recommendations, and an appendix includes a draft of proposed wording for modification of the AASHTO LRFD Specifications to include these design recommendations. In addition, a spreadsheet was developed in Microsoft EXCEL to accomplish the calculations necessary to complete the design.

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

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

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/569.1.pdf http://wsdot.wa.gov/Research/Reports/500/569.1.htm

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

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

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

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/532.1.pdf http://wsdot.wa.gov/Research/Reports/500/532.1.htm

Abstract:
This working paper, 'Travel Patterns in Mixed Use Neighborhoods,' summarizes Phase I of a research effort by the Innovations Unit of the Washington State Transportation Commission. The study is based on previous Innovations Unit research, described in the 1992 report, Land Use-Transportation Linkage (Kestle et al. 1992), the focus of which was the impact of land use policies on transportation systems. This working paper describes surveys conducted in four neighborhoods in the state of Washington (three in King County and one in Spokane) to gather data on travel behavior in neighborhoods that have a good mix of housing, shopping, and services; in other words, mixed use neighborhoods. The survey consisted of telephone interviews to determine household characteristics and the subsequent collection of travel diaries to assess household travel habits by mode and purpose. Preliminary results indicate the preponderance of trips for both family and personal business on both weekdays and weekends. Although auto is the dominant mode, results indicate the potential for shared rides in all neighborhoods and for the walk mode in the in-city neighborhoods. Directions for future research are suggested, including the study of the potential for reducing vehicle miles traveled (VMT) in mixed use neighborhoods; the relationships among mixed use development, household demographics, and travel behavior; the possibility of substituting walking for auto use; and methods for alleviating weekend traffic congestion based on a better understanding of the components of weekend travel.

Authors:
Zemotel,L., Nielsen,K., Rutherford,G. S., Ishimaru,J. M.

Keywords:
mixed use, research, innovation, Washington, Washington state, transportation, linkage, land use, land-use, policy, systems, survey, counties, data, travel behavior, behavior, development, walking, traffic, traffic congestion, congestion

Abstract:
This report is designed to provide information to guide inspectors of wood highway structures in the use of stress wave inspection technology. It explains the methods and instruments used to measure the velocity of stress waves (sound) in wood. The characteristic behavior of sound waves in wood of various species, moisture content, preservative treatment and infection by wood destroying organisms is described. The important effects of the anatomy of wood and the orientation of grain and annual rings to the wave path are discussed to aid in the interpretation of measurements. Characteristics of the instrumentation essential to its calibration are explained and instruction is provided in the appropriate use of these tools. This report has been written to serve as a manual for \"on site \" stress wave inspection of the kind of wood structures found in highway systems. It is a compendium or experience in the field inspection of many wood buildings and highway bridges. Original research conducted to fill in voids in the published studies, is described in the Appendices.

Authors:
Hoyle,R. J. Jr, Rutherford,G. S.

Keywords:
behavior, bridge, bridges, calibration, grain, highway, insect damage, inspection, ITS, manual, nondestructive testing, research, sound waves, Stress waves, stresses, structures, systems, technology, termite damage, velocity, wood decay

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Abstract:
This research has attempted to determine the distribution of precipitation in the complex terrain of Washington State. The first part of this report examines the precipitation distribution for various large scale wind directions. It is found that there are meaningful shifts in the precipitation pattern as the large scale wind changes direction and that edge of this behavior can be useful for operational applications. The second section presents a simple numerical model of precipitation in complex terrain. Although the results are not perfect by any means, they can usefully indicate the variation precipitation in the mountains of our area. However, such a model requires at least a minicomputer to run it.

Authors:
Speers,P., Mass,C. F.

Keywords:
applications, behavior, Complex Terrain, Diagnosis, model, Precipitation, prediction, Regions, research, Washington, Washington state, wind

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Abstract:
This study was undertaken to measure and assess current transportation behavior, attitudes, and adjustments people have made or are planning to make to cope with higher costs of transportation and energy shortages. A secondary objective was to develop an effective and inexpensive system to collect a sizeable amount of multimodal data for various types of travel from a statistically reliable sample of modal data for various types of travel from a statistically reliable sample of households in the State of Washington. Telephone interviews of approximately 15 minutes in length were conducted with 2,500 households in 1980 and 2,000 homes in 1983, with both samples having a 95 percent confidence level. Residents of metropolitan, urban and rural areas were included. The households interviewed were selected by a random computer search of telephone numbers. Respondents were screened to ensure that an adult member (18 years or older) of the household was interviewed. The questionnaire dealt with the travel habits of the household rather than just the person being interviewed. Travel to work, local travel, long distance travel, recreational travel, use of public transit and other modes of travel, as well as vehicle ownership trends were topics covered in the interviews. The household's travel patterns two years prior to the interview, as well as current behavior and future plans were included. The replies to the questions indicated that people were concerned about transportation problems and were willing to provide detailed facts and opinions about their household's transportation behavior.

Authors:
Limotti,Brian, Iverson,Evan, Jacobson,Robert

Keywords:
attitudes, behavior, computer, condition, cost, costs, data, data collection, Energy, energy shortages, households, interviews, multimodal, planning, public, public transit, Recreational travel, ridership, rural, Surveys, System, transit, transportation, travel, travel patterns, urban, Washington, Washington state

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Abstract:
The research study identifies the types and amounts of recreational travel in Washington State, assess the impact of gasoline supply and price, investigates the attitudes of local and out-of-state travelers regarding travel in the past, present and future. The future includes a gasoline price scenario. The study also addresses the reasons for change in recreational travel behavior and provides recommendations to minimize the adverse effects of gasoline prices on recreational travel.

Authors:
Hamstra,Thomas, Motoyoshi,Paul

Keywords:
attitudes, behavior, impact, Recreational travel, Recreational Travel Modes, research, Study, travel, travel behavior, Trip Distance, Trip Duration, Trip Frequency, Washington, Washington state

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Abstract:
As part of their continuing effort to prolong the life of existing pavement systems, highway engineers must continue to improve upon design and rehabilitation methods. In past years, design methods based upon empericism have been employed with considerable success. As loading and materials change or become more complex, the older practices become less useful and a new approach undertaken. Throughout the U.S. and elsewhere, there has been emerging new technology often termed " rational " , "systematic", "mechanistic", and other terms used to describe new approaches to pavement analysis and design. Mostof these are based on elastic or viscoelastic layered representation of the pavement structure and have the potential to become powerful tools for the highway engineer. In recent years, the University of Washington has assisted the Washington State Highway Department on various research projects . One project resulted in a report that has been used to develop guidelines for allowable truck traffic through the concept of pavement damage and/or remaining life . The basis forth is report was the concept that pavement structures can be reasonably well represented by elastic layered systems. Analysis of the mechanistic behavior can then be used to predict pavement response and l i f e expectancy. As a result of this study and after discussions with Highway Department personnel, it was determined that the procedures, techniques, as well as other information used in the above report may be of further interest to them. In other words, the methods as well as results had potential utilization in a wide range of applications . As a result , a seminar program was set up whereby the writer would conduct or lead weekly discussion sessions on key topics.

Authors:
Terrel,R. L.

Keywords:
analysis, applications, behavior, damage, design, highway, materials, mechanistic, pavement, pavement damage, program, rehabilitation, remaining life, research, seminar, structures, systems, technology, traffic, truck, Washington, Washington state

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Abstract:
A collection of reports resulting from the first year's study Alternate Methods of Avalanche Control. The reports are entitled:1. Air Bag System by E. R. LaChappelle and P.L. Taylor2. Gas Exploder System by E. R. LaChappelle and P. L. Taylor3. Snow Behavior Behind a Continuous Avalanche Defense Structure by J.A. Langdon.4. Interface Modification Field Tests by E. R. LaChappelle5. Mechanical Resonance of Snow by J. B. Johnson and R. J. Evans6. The 1974-75 Winter by M. B. Moore

Authors:
Brown,C. B., Evans,R. J., Johnson,B., Langdon,A., Moore,B., Taylor,L.

Keywords:
alternative, avalanche, avalanche forecasting, snow, weather, creep, glide, behavior, control, field test, interim, tests, winter

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Abstract:
There are indications that many trucks now have front axle loads approaching the maximum allowable for single axles which increases the potential for pavement damage. This report is intended to be a State-Of-The-Art approach to answer several pertinent questions from a theoretical study based on hypothetical pavements and loads, but based on reasonable material characteristics and pavement behavior from previous research. The results are a series of relationships based on pavement life which can be used to determine any number of "equivalencies." These equivalencies can be used to compare the destructive effects of various sizes of single and dual tires, axle loads , pavement thicknesses , speed and temperatures. The general nature of this report provides a wide range of conditions for comparison.on a relative basis.

Authors:
Terrel,R., Rimsritong,S.

Keywords:
asphalt pavement, axle, behavior, condition, damage, dual tires, equivalencies, loads, pavement, pavement damage, pavement life, pavements, research, single axle, speed, speed and temperature, state-of-the-art, temperature, tire, tire contact pressure, tires, truck, trucks, wheel load

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Abstract:
This present compilation of avalanche paths affecting Washington State highways extends in the same format the information published in 1971 as the North Cascades Highway Avalanche Atlas. Part 11, in preparation, will cover Stevens Pass and Tumwater Canyon.The North Cascades Highway Atlas was prepared on the basis of extensive aerial and ground reconnaissance in a hitherto inaccessible wilderness area where no previous record of avalanche occurrence was available. Compilation for the Cascades Passes has proceeded on the same basis, with the added advantage that all of the areas in question have long been traversed by highways for which considerable historical records exist . It is necessary, though, to note that such a record has proven to be less advantageous than might be expected. In the case of the North Cascades Highway, identification of avalanche paths was based on objective appraisal of terrain and vegetation patterns, leading to an accurate and highly consistent compilation. In the present Cascade Passes Atlas, there are many instances where objective evidence and historical accounts fail to agree. Moreover, the nomenclature, rather than being assigned consistently, has developed -- ad hoc over the years and varies with individuals and agencies . These conflicts have been resolved in the final editing of this Atlas according to the best available evidence, but in some cases necessarily in an arbitrary fashion. The Snoqualmie Pass section of this Atlas includes reproductions of sketches prepared by the Department of Highways for use in recording avalanche occurrences. These sketches are included here to illustrate this mode of avalanche recording, since it is a valuable method for systematically accumulating an historical record of avalanche frequency and behavior.

Authors:
LaChapplle,E. R., Brown,C. B., Evans,R. J.

Keywords:
account, agencies, Atlas, avalanche, behavior, Cascade, developed, highway, Highways, North, North Cascade, Washington, Washington state

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Abstract:
The objectives of this research are two-fold: 1) to identify characteristics of recreational trips, and 2) to identify factors influencing the distribution of recreational trips. Characteristics of recreational trips have been identified on the basis of data collected from different state agencies in the State of Washington. Seven recreational trip purposes which are characteristic for the State of Washington have been identified in this study: 1) camping trips, 2) hunting trips 3) fishing trips, 4) visiting beaches and clamming, 5) snow skiing, 6) driving for pleasure and sightseeing, and 7) others.The analysis has been performed basically for the spatial and temporal distribution of recreational trips. Spatial distribution relates to the location of the recreational opportunities which can clearly be distinct for each of the trip purposes and is further characterized by the trip-length frequency connected with each of these trip purposes. Temporal distribution is related primarily to the seasons within which the activity corresponding to the trip purpose can be pursued.A further reason for classifying recreational trips into these seven purposes is the difference in travel behavior that can be observed in connection with trip purposes. For example, hunting, fishing, and snow skiing are trips with a distinct destination, and the trip maker tends to select the shortest route to his destination in order to minimize the travel time. Travel to the trip destination is not, therefore, an essential part of the recreation experience. On the other hand, driving for pleasure and sightseeing creates different travel behavior.

Authors:
Leonhardt,K.

Keywords:
agencies, analysis, behavior, data, objectives, recreation, Recreational travel, research, season, snow, travel, travel behavior, travel patterns, travel time, trip length, Washington, Washington state

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Abstract:
In many parts of the world, the design of flexible pavement is still based on empirical methods which have developed from engineering experience. These empirical methods cannot be extrapolated beyond their limits without full scale trials to prove their applicability. In recent years, however, the increase of traffic, both in volume and axle loads, has led to the failure of many roads previously considered well designed. For this reason, therefore, researchers realized that a closer look at the pavement materials was desirable in order to develop a rational design procedure. Due to the complexity of characterizing pavement materials, and the limitations of instrumentation, much of the reported work offered little help in changing design practice. This is, perhaps, due to many simplifying assumptions which had to be introduced in the experimental procedure as well as the interpretation of the test results. Recently, however, there has been a sharp advancement in test instrumentation and an outstanding progress in processing the experimental results. This has been reflected through many fine investigations and has increased the demand for more improvements. An asphalt pavement is a complex structure whose function is to provide a suitable surface for a highway, an airport, or other off-highway facility. The load of a vehicle or an aircraft is transmitted through the multilayered system of processed materials which have different mechanical properties. The stress distribution within this system is highly complex and to a large extent is dependent on the relative stiffnesses of the individual layers.

Authors:
Terrel,Ronald L., Awad,S.

Keywords:
asphalt, asphalt pavement, axle, base, behavior, demand, design, developed, experimental, facilities, fine, highway, improvement, loads, materials, methods, pavement, stiffness, stresses, System, traffic, volume

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Abstract:
The purpose of this study was threefold: (1) Develop empirical equivalencies from all four rings, (2) develop a design method for overlays based on field deflections; and (3) evaluate the validity of data obtained from instrumentations in terms of n-layer elastic theory and then develop theoretical equivalencies.This was done. Field equivalencies were developed and they indicated that superiority of the treated base materials over the untreated. A design method was developed which could be used for predicting when an overlay was needed and what thickness was needed to withstand certain equivalent wheel loads and deflections.Using computer programs for n-layer elastic theory developed by Chevron Research Company, deflection stresses and strains were computed and compared with field data. Assumptions about the material behavior and condition were made based on laboratory data obtained from The Asphalt Institute and field knowledge, and were used to help predict the behavior of pavements. The results were encouraging and indicate that field measurements generally were comparable with elastic layer theory predictions. This will help to develop and modify existing design limits for stresses, strains and deflection for future work.Equivalencies based on theoretical deflections, stresses and strains indicate the difficulty of assigning precise values. These values also indicate the superiority of treated materials over the untreated materials.

Authors:
Krukar,M., Cook,J. C.

Keywords:
analysis, asphalt, base, base materials, behavior, computer, computer program, condition, data, design, equivalencies, evaluation, experimental, loads, materials, overlay, overlays, pavement, pavements, prediction, program, research, strains, stresses, volume, wheel load

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