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Aziz,A. M. | WA-RD 675.1 | Performance Analysis and Forecasting for WSDOT Highway Projects | 2007 | TRAC/UW |
Abstract:
Improving the way that WSDOT performs business is an important objective to pursue. The objectives of this research were to develop tools that will monitor the contractor’s performance during construction in order to detect any unsatisfactory progress, and to develop tools that will improve the time and cost prediction of highway projects in order to reduce time and cost overruns. To achieve the first objective, the research surveyed other state DOTs about how they measure and evaluate work progress and contractor performance. The survey showed that a formal progress measurement and performance evaluation process is lacking in many states, and that there is an apparent lack of progress charts for measuring contractor performance. By using WSDOT historical project data on actual payment estimates and the elapsed working days of each estimate in each project, the current research developed minimum performance bounds and average performance bounds for a set of successfully completed projects using regression analysis. Performance bounds were developed for all projects and for clusters of projects grouped in categories based on quantities of asphalt concrete pavement/hot mix asphalt (ACP/HMA), contract value, project duration, and project miles. Time and cost prediction models were developed through the application of general multiple regression analysis, ridge regression analysis, and nonlinear partial least-square regression analysis on WSDOT historical project data. The models were developed on the basis of a number of major variables in pavement projects, including project duration (working days), final contract value (paid-to-contractor dollars), ACP/HMA quantity (tons), grading (tons, cy), surfacing (ton), and the number of project highway miles.
Authors:
Aziz,A. M.
Keywords:
performance and progress analysis, prediction, regression, estimating
Improving the way that WSDOT performs business is an important objective to pursue. The objectives of this research were to develop tools that will monitor the contractor’s performance during construction in order to detect any unsatisfactory progress, and to develop tools that will improve the time and cost prediction of highway projects in order to reduce time and cost overruns. To achieve the first objective, the research surveyed other state DOTs about how they measure and evaluate work progress and contractor performance. The survey showed that a formal progress measurement and performance evaluation process is lacking in many states, and that there is an apparent lack of progress charts for measuring contractor performance. By using WSDOT historical project data on actual payment estimates and the elapsed working days of each estimate in each project, the current research developed minimum performance bounds and average performance bounds for a set of successfully completed projects using regression analysis. Performance bounds were developed for all projects and for clusters of projects grouped in categories based on quantities of asphalt concrete pavement/hot mix asphalt (ACP/HMA), contract value, project duration, and project miles. Time and cost prediction models were developed through the application of general multiple regression analysis, ridge regression analysis, and nonlinear partial least-square regression analysis on WSDOT historical project data. The models were developed on the basis of a number of major variables in pavement projects, including project duration (working days), final contract value (paid-to-contractor dollars), ACP/HMA quantity (tons), grading (tons, cy), surfacing (ton), and the number of project highway miles.
Authors:
Aziz,A. M.
Keywords:
performance and progress analysis, prediction, regression, estimating
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Dailey,D. J. | WA-RD 655.1 | The Use of Weather Data to Predict Non-Recurring Traffic Congestion | 2006 | TRAC/UW |
Abstract:
This project demonstrates the quantitative relationship between weather patterns and surface traffic conditions. The aviation and maritime industries use weather measurements and predictions as a normal part of operations, and this can be extended to surface transportation. Data from two data mines on the University of Washington campus were combined to evaluate the quantitative relationship between freeway speed reduction and rain fall rate as measured by Doppler radar. The University of Washington’s Atmospheric Science department maintains an archive of Nexrad radar data, and the Electrical Engineering department maintains a data mine of 20-second averaged inductance loop data. The radar data were converted into rainfall rate, and the speed data from the inductance loop speed traps were converted into a deviation from normal performance measure. The deviation from normal and the rainfall rate were used to construct an impulse response function that can be applied to radar measurements to predict traffic speed reduction. This research has the potential to accomplish (1) prediction of non-recurring traffic congestion and (2) prediction of conditions under which incidents or accidents can have a significant impact on the freeway system. This linkage of weather to traffic may be one of the only non-recurring congestion phenomena that can be accurately predicted. This project created algorithms and implementations to correlate weather with traffic congestion. Furthermore, it may provide a means for traffic management to determine where and when to proactively place resources to clear incidents.
Authors:
Dailey,D. J.
Keywords:
Weather radar, weather forecasting, traffic congestion, nonrecurrent congestion, prediction, congestion management systems
This project demonstrates the quantitative relationship between weather patterns and surface traffic conditions. The aviation and maritime industries use weather measurements and predictions as a normal part of operations, and this can be extended to surface transportation. Data from two data mines on the University of Washington campus were combined to evaluate the quantitative relationship between freeway speed reduction and rain fall rate as measured by Doppler radar. The University of Washington’s Atmospheric Science department maintains an archive of Nexrad radar data, and the Electrical Engineering department maintains a data mine of 20-second averaged inductance loop data. The radar data were converted into rainfall rate, and the speed data from the inductance loop speed traps were converted into a deviation from normal performance measure. The deviation from normal and the rainfall rate were used to construct an impulse response function that can be applied to radar measurements to predict traffic speed reduction. This research has the potential to accomplish (1) prediction of non-recurring traffic congestion and (2) prediction of conditions under which incidents or accidents can have a significant impact on the freeway system. This linkage of weather to traffic may be one of the only non-recurring congestion phenomena that can be accurately predicted. This project created algorithms and implementations to correlate weather with traffic congestion. Furthermore, it may provide a means for traffic management to determine where and when to proactively place resources to clear incidents.
Authors:
Dailey,D. J.
Keywords:
Weather radar, weather forecasting, traffic congestion, nonrecurrent congestion, prediction, congestion management systems
|
Li, J. | WA-RD 588.1 | Application of HDM-4 in the WSDOT Highway System | 2004 | TRAC/UW |
Abstract:
This project performed extensive study and systematic research on the application of the Highway Development and Management system (HDM-4) to the Washington State Department of Transportation (WSDOT) highway system. Data processing, testing, calibration, and analysis were executed to provide the WSDOT with a new budget planning tool. HDM-4 flexible pavement deterioration models were calibrated with the assistance of the Washington State Pavement Management System. A method to calibrate concrete pavement distress models is proposed. This research also explored the application of HDM-4 analysis at the project, program, and strategic levels. The applications include prediction of pavement conditions during a defined analysis period, calculation of required budgets for optimal pavement conditions and maximum economic indicators, establishment of optimized work programs under varying levels of constrained budgets, and other applications for WSDOT.
Authors:
Li, J., Muench, S.T., Mahoney, J.P., Pierce, L., Sivaneswaran, N.
Keywords:
HDM-4, models, pavement maintenance, pavement management, pavement performance, Pavement preservation, vehicle operating costs, research, highway, development, management, management system, Washington, Washington state, transportation, WSDOT, data, calibration, analysis, planning, pavement, deterioration, concrete, program, applications, prediction, condition, indicators
This project performed extensive study and systematic research on the application of the Highway Development and Management system (HDM-4) to the Washington State Department of Transportation (WSDOT) highway system. Data processing, testing, calibration, and analysis were executed to provide the WSDOT with a new budget planning tool. HDM-4 flexible pavement deterioration models were calibrated with the assistance of the Washington State Pavement Management System. A method to calibrate concrete pavement distress models is proposed. This research also explored the application of HDM-4 analysis at the project, program, and strategic levels. The applications include prediction of pavement conditions during a defined analysis period, calculation of required budgets for optimal pavement conditions and maximum economic indicators, establishment of optimized work programs under varying levels of constrained budgets, and other applications for WSDOT.
Authors:
Li, J., Muench, S.T., Mahoney, J.P., Pierce, L., Sivaneswaran, N.
Keywords:
HDM-4, models, pavement maintenance, pavement management, pavement performance, Pavement preservation, vehicle operating costs, research, highway, development, management, management system, Washington, Washington state, transportation, WSDOT, data, calibration, analysis, planning, pavement, deterioration, concrete, program, applications, prediction, condition, indicators
|
http://www.wsdot.wa.gov/research/reports/fullreports/588.1.pdf http://wsdot.wa.gov/Research/Reports/500/588.1.htm |
Kopf,J. | WA-RD 592.1 | Reflectivity of Pavement Markings: Analysis of Retroreflectivity Degradation Curves | 2004 | TRAC/UW |
Abstract:
The intent of this project was to develop retroreflectivity degradation curves for roadway pavement markings. To accomplish this objective, this study utilized a vehicle-mounted Laserlux retroreflectometer to take measurements on approximately 80 test sections throughout Washington state. The resulting retroreflectivity values from roadways with similar average annual daily traffic (AADT) and environments displayed a significant amount of variability. Best-fit trendlines were extrapolated to determine when each category of paint would fall below a selected minimum threshold of 100 mcd/m2/lux and require repainting.Unfortunately, given the variability of the data observed to date, it may not be possible, even with the collection of more data, to create striping performance predictions that have a high level of statistical confidence. According to that schedule, long line painted markings should be painted at least once a year, and heavy wear, long line pavement markings should be painted at least twice a year.
Authors:
Kopf,J.
Keywords:
degradation curves, Laserlux retroreflectometer, pavement, pavement markings, retroreflectivity, roadway, Washington, Washington state, traffic, environment, data, performance, prediction, line
The intent of this project was to develop retroreflectivity degradation curves for roadway pavement markings. To accomplish this objective, this study utilized a vehicle-mounted Laserlux retroreflectometer to take measurements on approximately 80 test sections throughout Washington state. The resulting retroreflectivity values from roadways with similar average annual daily traffic (AADT) and environments displayed a significant amount of variability. Best-fit trendlines were extrapolated to determine when each category of paint would fall below a selected minimum threshold of 100 mcd/m2/lux and require repainting.Unfortunately, given the variability of the data observed to date, it may not be possible, even with the collection of more data, to create striping performance predictions that have a high level of statistical confidence. According to that schedule, long line painted markings should be painted at least once a year, and heavy wear, long line pavement markings should be painted at least twice a year.
Authors:
Kopf,J.
Keywords:
degradation curves, Laserlux retroreflectometer, pavement, pavement markings, retroreflectivity, roadway, Washington, Washington state, traffic, environment, data, performance, prediction, line
|
http://www.wsdot.wa.gov/research/reports/fullreports/592.1.pdf http://wsdot.wa.gov/Research/Reports/500/592.1.htm |
Holtz,R. D. | WA-RD 532.1 | Internal Stability Analyses of Geosynthetic Reinforced Retaining Walls | 2002 | TRAC/UW |
Abstract:
This research project was an effort to improve our understanding of the internal stress-strain distribution in GRS retaining structures. Our numerical modelling techniques utilized a commercially available element program, FLAC (Fast Lagrangian Analysis of Continua). In this research, we investigated and appropriately considered the plane strain soil properties, the effect of low confining pressure on the soil dilation angle, and in-soil and low strain rate geosynthetic reinforcement properties.Modeling techniques that are able to predict both the internal and external performance of GRS walls simultaneously were developed. Instrumentation measurements such as wall deflection and reinforcement strain distributions of a number of selected case histories were successfully reproduced by our numerical modeling techniques. Moreover, these techniques were verified by successfully performing true "Class A" predictions of three large-scale experimental walls.An extensive parametric study that included more than 250 numerical models was then performed to investigate the influence of design factors such as soil properties, reinforcement stiffness, and reinforcement spacing on GRS wall performance. Moreover, effects of design options such as toe restraint and structural facing systems were examined. An alternative method for internal stress-strain analysis based on the stress-strain behavior of GRS as a composite material was also developed. Finally, the modeling results were used to develop a new technique for predicting GRS wall face deformations and to make recommendations for the internal stability design of GRS walls.
Authors:
Holtz,R. D., Lee,W. F.
Keywords:
analysis, behavior, design, experimental, FLAC, geosynthetic, geotechnical, materials, modeling, models, performance, prediction, pressure, program, reinforcement, research, retaining wall, retaining walls, stability, structures, systems, walls
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
|
http://www.wsdot.wa.gov/research/reports/fullreports/532.1.pdf http://wsdot.wa.gov/Research/Reports/500/532.1.htm |
Dailey,D. J. | WA-RD 537.1 | A Cellular Automata Model for Use with Real Freeway Data | 2002 | TRAC/UW |
Abstract:
The exponential rate of increase in freeway traffic is expanding the need for accurate and realistic methods to model and predict traffic flow. Traffic modeling and simulation facilitate an examination of both microscopic and macroscopic views of traffic flows and are therefore considered one of the most important analytical tools in traffic engineering. This report presents a cellular automata model for traffic flow simulation and prediction (CATS). Cellular automata models quantize complex behavior into simple individual components. In this model, the freeway being simulated is discretized into homogeneous cells of equal length, and time is discretized into timesteps of equal duration. The CATS model allows users to define locations within the road topology where volume and density data will be calculated so that the model results can be compared to observed highway data.
Authors:
Dailey,D. J., Taiyab,N.
Keywords:
cellular automata, traffic modeling, dynamic simulation, prediction, control, ramp metering, research
The exponential rate of increase in freeway traffic is expanding the need for accurate and realistic methods to model and predict traffic flow. Traffic modeling and simulation facilitate an examination of both microscopic and macroscopic views of traffic flows and are therefore considered one of the most important analytical tools in traffic engineering. This report presents a cellular automata model for traffic flow simulation and prediction (CATS). Cellular automata models quantize complex behavior into simple individual components. In this model, the freeway being simulated is discretized into homogeneous cells of equal length, and time is discretized into timesteps of equal duration. The CATS model allows users to define locations within the road topology where volume and density data will be calculated so that the model results can be compared to observed highway data.
Authors:
Dailey,D. J., Taiyab,N.
Keywords:
cellular automata, traffic modeling, dynamic simulation, prediction, control, ramp metering, research
|
http://www.wsdot.wa.gov/research/reports/fullreports/537.1.pdf http://wsdot.wa.gov/Research/Reports/500/537.1.htm |
Leahy,R. B. | WA-RD 486.1 | Superpave--Washington DOT's Assessment and Status | 1999 | Civil Construction and Environmental Engineer |
Abstract:
Funded by the 1987 Intermodal Surface Transportation Efficiency Act, the Strategic Highway Research Program (SHRP), was a five year, $150 million research program to improve the performance of the nation's roads by addressing four key areas: concrete and structures; highway safety and maintenance; asphalt; and long-term pavement performance. Nearly one-third of the $150 million was allocated for the study of asphalt, specifically to develop performance based specifications that would relate material properties of the binder and the mix to field performance. Superpave (Superior PERforming asphalt PAVEments) encompasses the products of the SHRP asphalt research program and consists of three interrelated elements: an asphalt binder specification with supporting tests; a mix design and analysis system with supporting tests; and performance prediction models. This report is a compilation and synthesis of Washington DOT's (WSDOT) experience with selected components and concepts of the SHRP/Superpave technology to include the following: performance graded (PG) binder usage and specification validation; gyratory mix design; the Superpave Shear Test (SST); and field performance of the Superpave mixes.Binders typically specified by WSDOT (AR400OW and PBAs -2, -5, -6. -6GR) were classified in terms of five Superpave performance grades: PG 58-22; 64-22; 64-28; 64-34; and 70-28. Although data from 171 weather stations suggest that as many as 6 low- and 5 high-temperature grades could be specified, binder availability and regional pavement distress were used to develop guidelines for statewide PG usage. Three binders were recommended for use in the western, northeastern and southeastern regions of the state as follows: PG 58-22; PG 58-34; and PG 64-28, respectively. Validation of the binder specification with respect to low temperature cracking was accomplished using binder and field performance data from 28 projects. The results were very encouraging: the original SHRP algorithm for binder selection correctly "predicted" field performance in 22 of 28 cases, whereas the LTPP algorithm for binder selection correctly "predicted" field performance in 26 of 28 cases.Additionally, a laboratory experiment using the Superpave Shear Test (SST) apparatus was undertaken to test the effectiveness of binder "bumping," i.e., increasing the high temperature grade because of exceptionally high traffic volume and/or slow or standing traffic. The data clearly indicate that the SST is an effective tool for discriminating between binders and that 'bumping" may be effective in reducing pavement rutting. Permanent shear strain for specimens made with a PB 70-xx binder was only 25 to 33% of the shear strain for specimens made with a PG 58-xx binder.As originally configured, the Superpave mix design matrix included seven traffic levels and four temperature regimes for 28 possible compaction levels. Recognizing that the 28 compaction levels made for a somewhat unwieldy system, WSDOT attempted to reduce the number of compaction levels by conducting a series of mix designs at each compaction level. The results of the limited experiment suggest that it might be possible to limit the number of compaction levels required for mix design. Research by Brown et. al. (NCHRP 99) tends to confirm this as they have suggested reducing the number of compaction levels and provided more definitive guidance with respect to each level.Since 1993 WSDOT has place 44 projects which include some component of the Superp ave technology. For 17 of these projects parallel Hveem and Superpave mix designs were conducted. In 13 of the 17 cases, the Superpave design asphalt content was equal to or greater than the Hveem design asphalt content, though the difference was usually no more than 0.2%. A fundamental difference between Hveem and Superpave mix design methods is the compaction device. Data from these field projects indicate that the current kneading and gyratory compaction protocols (at least for 109 gyrations) yield similar air void contents.As noted previously, Washington DOT has placed 44 projects which involve some component of the Superpave technology. For 18 of the projects a conventional Hveem mix design was conducted using a PG binder (Hveem-PG). The remaining 26 projects were truly Superpave, i.e., the materials selection and mix design were established in accordance with the Asphalt Institute's SP2, Superpave Level 1 Mix Design. According to WSDOT practice the following numerical indices trigger maintenance: Pavement Structural Condition (PSC) 10 mm; or International Roughness Index (IRI) > 500 cnVkm. Although relatively "young", the 44 projects are performing quite well. The average values of rutting, PSC, and IRI (4, 91, and 121, respectively) are all well below the "trigger" values. With respect to rutting and PSC, the performance of Hveem-PG and Superpave projects is virtually identical. However, the ride quality of the Superpave projects is a bit rougher than the Hveem-PG binder projects: IRI of 134 for the former and 103 for the latter. The higher values of IRI measured on the Superpave projects may be the result of the typically coarser aggregate gradation or differences in construction techniques.WSDOT's Superpave experience has not been without challenges. Still, its overall experience has been very encouraging. Experimentation with the revised compaction matrix, continued use of the SST, field validation of the "bumping" experiment, and long-term monitoring of field performance will provide the necessary data to allow WSDOTs critical assessment of Superpave's technical merit and economic viability.
Authors:
Leahy,R. B., Briggs,R. N.
Keywords:
SHRP, Superpave, asphalt, intermodal, transportation, transportation efficiency, highway, research, program, performance, concrete, structures, highway safety, safety, maintenance, pavement, specifications, specification, asphalt pavement, pavements, tests, design, analysis, prediction, models, Washington, WSDOT, data, temperature, cracking, LTPP, traffic, volume, compaction, materials, condition, international roughness index, roughness, index, ride quality, quality, aggregate, construction, ITS, monitoring
Funded by the 1987 Intermodal Surface Transportation Efficiency Act, the Strategic Highway Research Program (SHRP), was a five year, $150 million research program to improve the performance of the nation's roads by addressing four key areas: concrete and structures; highway safety and maintenance; asphalt; and long-term pavement performance. Nearly one-third of the $150 million was allocated for the study of asphalt, specifically to develop performance based specifications that would relate material properties of the binder and the mix to field performance. Superpave (Superior PERforming asphalt PAVEments) encompasses the products of the SHRP asphalt research program and consists of three interrelated elements: an asphalt binder specification with supporting tests; a mix design and analysis system with supporting tests; and performance prediction models. This report is a compilation and synthesis of Washington DOT's (WSDOT) experience with selected components and concepts of the SHRP/Superpave technology to include the following: performance graded (PG) binder usage and specification validation; gyratory mix design; the Superpave Shear Test (SST); and field performance of the Superpave mixes.Binders typically specified by WSDOT (AR400OW and PBAs -2, -5, -6. -6GR) were classified in terms of five Superpave performance grades: PG 58-22; 64-22; 64-28; 64-34; and 70-28. Although data from 171 weather stations suggest that as many as 6 low- and 5 high-temperature grades could be specified, binder availability and regional pavement distress were used to develop guidelines for statewide PG usage. Three binders were recommended for use in the western, northeastern and southeastern regions of the state as follows: PG 58-22; PG 58-34; and PG 64-28, respectively. Validation of the binder specification with respect to low temperature cracking was accomplished using binder and field performance data from 28 projects. The results were very encouraging: the original SHRP algorithm for binder selection correctly "predicted" field performance in 22 of 28 cases, whereas the LTPP algorithm for binder selection correctly "predicted" field performance in 26 of 28 cases.Additionally, a laboratory experiment using the Superpave Shear Test (SST) apparatus was undertaken to test the effectiveness of binder "bumping," i.e., increasing the high temperature grade because of exceptionally high traffic volume and/or slow or standing traffic. The data clearly indicate that the SST is an effective tool for discriminating between binders and that 'bumping" may be effective in reducing pavement rutting. Permanent shear strain for specimens made with a PB 70-xx binder was only 25 to 33% of the shear strain for specimens made with a PG 58-xx binder.As originally configured, the Superpave mix design matrix included seven traffic levels and four temperature regimes for 28 possible compaction levels. Recognizing that the 28 compaction levels made for a somewhat unwieldy system, WSDOT attempted to reduce the number of compaction levels by conducting a series of mix designs at each compaction level. The results of the limited experiment suggest that it might be possible to limit the number of compaction levels required for mix design. Research by Brown et. al. (NCHRP 99) tends to confirm this as they have suggested reducing the number of compaction levels and provided more definitive guidance with respect to each level.Since 1993 WSDOT has place 44 projects which include some component of the Superp ave technology. For 17 of these projects parallel Hveem and Superpave mix designs were conducted. In 13 of the 17 cases, the Superpave design asphalt content was equal to or greater than the Hveem design asphalt content, though the difference was usually no more than 0.2%. A fundamental difference between Hveem and Superpave mix design methods is the compaction device. Data from these field projects indicate that the current kneading and gyratory compaction protocols (at least for 109 gyrations) yield similar air void contents.As noted previously, Washington DOT has placed 44 projects which involve some component of the Superpave technology. For 18 of the projects a conventional Hveem mix design was conducted using a PG binder (Hveem-PG). The remaining 26 projects were truly Superpave, i.e., the materials selection and mix design were established in accordance with the Asphalt Institute's SP2, Superpave Level 1 Mix Design. According to WSDOT practice the following numerical indices trigger maintenance: Pavement Structural Condition (PSC) 10 mm; or International Roughness Index (IRI) > 500 cnVkm. Although relatively "young", the 44 projects are performing quite well. The average values of rutting, PSC, and IRI (4, 91, and 121, respectively) are all well below the "trigger" values. With respect to rutting and PSC, the performance of Hveem-PG and Superpave projects is virtually identical. However, the ride quality of the Superpave projects is a bit rougher than the Hveem-PG binder projects: IRI of 134 for the former and 103 for the latter. The higher values of IRI measured on the Superpave projects may be the result of the typically coarser aggregate gradation or differences in construction techniques.WSDOT's Superpave experience has not been without challenges. Still, its overall experience has been very encouraging. Experimentation with the revised compaction matrix, continued use of the SST, field validation of the "bumping" experiment, and long-term monitoring of field performance will provide the necessary data to allow WSDOTs critical assessment of Superpave's technical merit and economic viability.
Authors:
Leahy,R. B., Briggs,R. N.
Keywords:
SHRP, Superpave, asphalt, intermodal, transportation, transportation efficiency, highway, research, program, performance, concrete, structures, highway safety, safety, maintenance, pavement, specifications, specification, asphalt pavement, pavements, tests, design, analysis, prediction, models, Washington, WSDOT, data, temperature, cracking, LTPP, traffic, volume, compaction, materials, condition, international roughness index, roughness, index, ride quality, quality, aggregate, construction, ITS, monitoring
|
Casavant,K. L. | WA-RD 206.1 | Procedure for Predicting and Estimating the Impact of Rail Line Abandonments on Washington Roads | 1989 | TRAC/WSU |
Abstract:
This summary report describes four case studies of rail line abandonment in Washington. These case studies were used to test a conceptual approach to predicting the location and magnitude of road damage caused by rail line abandonment. The procedure developed in the study worked well, especially as modified in the report to include District personnel in the analysis of potential road impacts. Proactive use of this procedure is dependent on continual monitoring of potential rail line abandonment candidates. Similar procedures should be developed to predict impacts on energy, environment, safety, and economic development.
Authors:
Casavant,K. L., Lenzi,J. C.
Keywords:
road damage, rail line abandonment, prediction, impacts
This summary report describes four case studies of rail line abandonment in Washington. These case studies were used to test a conceptual approach to predicting the location and magnitude of road damage caused by rail line abandonment. The procedure developed in the study worked well, especially as modified in the report to include District personnel in the analysis of potential road impacts. Proactive use of this procedure is dependent on continual monitoring of potential rail line abandonment candidates. Similar procedures should be developed to predict impacts on energy, environment, safety, and economic development.
Authors:
Casavant,K. L., Lenzi,J. C.
Keywords:
road damage, rail line abandonment, prediction, impacts
|
Fragaszy,R. J. | WA-RD 163.1 | Estimating Pile Capacity | 1988 |
Abstract:
A comparative study of ten pile driving formulas is described. The formulas are the Danish, ENR, Eytelwein, Gates, Hiley, Janbu, Navy-McKay, PCUBC, and Weisbach. The ultimate load for each of sixty-three load tests was determined using the Q-D over 30 method to determine ultimate capacity.The predicted pile capacity was by the measured capacity to obtain normalized values. analysis for coefficient of variation were performed on the logarithm of the normal capacities to determine which formula provided the most consistent prediction of pile capacity. The Gates formula proved to be the best and the widely used one of the worst with a coefficient of variation approximately 2-3 times higher than that for the Gates formula.
Authors:
Fragaszy,R. J., Higgins,J. D., Argo,J. D.
Keywords:
analysis, factor of safety, pile capacity, pile driving formulas, pile formulas, pile-driving, piles, prediction, tests, ultimate capacity
A comparative study of ten pile driving formulas is described. The formulas are the Danish, ENR, Eytelwein, Gates, Hiley, Janbu, Navy-McKay, PCUBC, and Weisbach. The ultimate load for each of sixty-three load tests was determined using the Q-D over 30 method to determine ultimate capacity.The predicted pile capacity was by the measured capacity to obtain normalized values. analysis for coefficient of variation were performed on the logarithm of the normal capacities to determine which formula provided the most consistent prediction of pile capacity. The Gates formula proved to be the best and the widely used one of the worst with a coefficient of variation approximately 2-3 times higher than that for the Gates formula.
Authors:
Fragaszy,R. J., Higgins,J. D., Argo,J. D.
Keywords:
analysis, factor of safety, pile capacity, pile driving formulas, pile formulas, pile-driving, piles, prediction, tests, ultimate capacity
|
Speers,P. | WA-RD 091.1 | Diagnosis And Prediction Of Precipitation In Regions Of Complex Terrain | 1986 |
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
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
|
Foss,Rene N. | WA-RD 033.1 | Ground Plan Wind Shear Interaction On Acoustic Transmission 949 | 1978 |
Abstract:
Experimental data indicate that the combined effects of wind shear and ground plane attenuation can have a strong influence on sound propagation near the ground even at distances as short as 100 ft, The effectmanifests itself experimentally as a noticeable difference between sound propagation upwind vis-8-vis downwind that becomes more pronounced with either increased distance or increased wind speed. Differences of up to 25 dBA were found between into-the-wind and with-the-wind propagation fora listening height of 4 ft and a transmission distance of about 300 ft. Even a very moderate wind (4 mph) produced a difference of 12 dB at 150 ft for the same listening height. A large body of spectral data was also taken under a variety of wind conditions for path lengths of 150 ft and 225 ft. The resulting spectra agreed reasonably well with theoretical predictions for frequencies below 500 Hz, where ground and surface waves predominate; an important observation is that these waves were not affected substantially by wind conditions. Above approximately 500 Hz, the attenuation was frequently more than that predicted theoretically, and it was wind sensitive. The effect of wind was, in many cases, large, and could well mean that much experimentally obtained highway noise data is considerably less useful than previously thought, unless wind shear was taken into account during the measurements. In general, to "hear" the full effect of existing traffic, measurements should be made when the test positions downwind from the traffic.
Authors:
Foss,Rene N.
Keywords:
account, attenuation, condition, data, experimental, highway, Highway acoustics, ground plane attenuation, wind shear, interaction, noise, prediction, speed, traffic, wind
Experimental data indicate that the combined effects of wind shear and ground plane attenuation can have a strong influence on sound propagation near the ground even at distances as short as 100 ft, The effectmanifests itself experimentally as a noticeable difference between sound propagation upwind vis-8-vis downwind that becomes more pronounced with either increased distance or increased wind speed. Differences of up to 25 dBA were found between into-the-wind and with-the-wind propagation fora listening height of 4 ft and a transmission distance of about 300 ft. Even a very moderate wind (4 mph) produced a difference of 12 dB at 150 ft for the same listening height. A large body of spectral data was also taken under a variety of wind conditions for path lengths of 150 ft and 225 ft. The resulting spectra agreed reasonably well with theoretical predictions for frequencies below 500 Hz, where ground and surface waves predominate; an important observation is that these waves were not affected substantially by wind conditions. Above approximately 500 Hz, the attenuation was frequently more than that predicted theoretically, and it was wind sensitive. The effect of wind was, in many cases, large, and could well mean that much experimentally obtained highway noise data is considerably less useful than previously thought, unless wind shear was taken into account during the measurements. In general, to "hear" the full effect of existing traffic, measurements should be made when the test positions downwind from the traffic.
Authors:
Foss,Rene N.
Keywords:
account, attenuation, condition, data, experimental, highway, Highway acoustics, ground plane attenuation, wind shear, interaction, noise, prediction, speed, traffic, wind
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Washington State Highway Commission Department of Highways | WA-RD 023.1 | Avalanche Hazard Forecasting Feasibility Study, Phase I -Final Report | 1975 |
Abstract:
This report describes the results of a feasibility study comprising Phase I of a Central AvalancheHazard Forecasting Program for mountain passes in the State of Washington. The report describes existing weather and avalanche data sources, and suggests improvements and additions for improved input to and feedback from a centralized avalanche forecaster's office which will improve avalanche predictions for all passes within the State. WSDH and consultant efforts and results during FY 75 are described, and specific recommendations for PhaseII, implementation of avalanche hazard forecasting, are provided.
Authors:
Washington State Highway Commission Department of Highways
Keywords:
avalanche, avalanche hazard, weather, weather observations, wind, temperature, precipitation, data reporting, avalanche hazard forecasting, communications, data, data sources, forecasting, hazard, prediction, program, Washington
This report describes the results of a feasibility study comprising Phase I of a Central AvalancheHazard Forecasting Program for mountain passes in the State of Washington. The report describes existing weather and avalanche data sources, and suggests improvements and additions for improved input to and feedback from a centralized avalanche forecaster's office which will improve avalanche predictions for all passes within the State. WSDH and consultant efforts and results during FY 75 are described, and specific recommendations for PhaseII, implementation of avalanche hazard forecasting, are provided.
Authors:
Washington State Highway Commission Department of Highways
Keywords:
avalanche, avalanche hazard, weather, weather observations, wind, temperature, precipitation, data reporting, avalanche hazard forecasting, communications, data, data sources, forecasting, hazard, prediction, program, Washington
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Roberts,E. I. | WA-RD 018.2 | Acoustic Barrier Interim Report SR 405, Wilburton Vicinity | 1974 |
Abstract:
On July 14, 1970, an access hearing was held for that section of SR 405 which includes the Wilburton Interchange. This study has shown that there is good correlation between community perception, computer prediction and physical measurement of noise levels and attenuation.Community ResponsesAn opinion questionnaire was sent by the Highway Department in October, 1973 to all the people in the Woodrodge Community who might be affected by the completed noise barrier. Returned questionnaires are shown in Appendix A. Resulsts show that most people living directly behind the barrier have noticed some improvement in the noise level. Since 3 dBA change is barely preceptible by most people, this correlates well with measured attenuation, as the respondents indicating "no change" all resided in areas where less that 3 dBA attenuation was measured. See map #2.The barrier, however, had little effect on truck noise which was expected since low frequency noises are so difficult to attenuate. Low frequency noise waves go over and around most barriers. Dr. Van Ostrand who lives at the south end of the barrier (house number 1513) notices an increase in truck noise which would be similar to a truck coming out of a tunnel. Generally those living directly behind the barrier had evenly divided opinions in the categories of "More", "Same", or "Less" noise from trucks. Only one person indicated technical knowledge about noise and made any specific observation. He indicated noticeable overall improvement but with no change in "spike" noises. Almost everyone returning a questionnaire agreed that the barrier is aesthetically acceptable.
Authors:
Roberts,E. I.
Keywords:
Acousitc, attenuation, barrier, barriers, computer, hearing, highway, Interim, noise, Noise Levels, prediction, Report SR 405, truck, trucks, Wilburton Vicinity
On July 14, 1970, an access hearing was held for that section of SR 405 which includes the Wilburton Interchange. This study has shown that there is good correlation between community perception, computer prediction and physical measurement of noise levels and attenuation.Community ResponsesAn opinion questionnaire was sent by the Highway Department in October, 1973 to all the people in the Woodrodge Community who might be affected by the completed noise barrier. Returned questionnaires are shown in Appendix A. Resulsts show that most people living directly behind the barrier have noticed some improvement in the noise level. Since 3 dBA change is barely preceptible by most people, this correlates well with measured attenuation, as the respondents indicating "no change" all resided in areas where less that 3 dBA attenuation was measured. See map #2.The barrier, however, had little effect on truck noise which was expected since low frequency noises are so difficult to attenuate. Low frequency noise waves go over and around most barriers. Dr. Van Ostrand who lives at the south end of the barrier (house number 1513) notices an increase in truck noise which would be similar to a truck coming out of a tunnel. Generally those living directly behind the barrier had evenly divided opinions in the categories of "More", "Same", or "Less" noise from trucks. Only one person indicated technical knowledge about noise and made any specific observation. He indicated noticeable overall improvement but with no change in "spike" noises. Almost everyone returning a questionnaire agreed that the barrier is aesthetically acceptable.
Authors:
Roberts,E. I.
Keywords:
Acousitc, attenuation, barrier, barriers, computer, hearing, highway, Interim, noise, Noise Levels, prediction, Report SR 405, truck, trucks, Wilburton Vicinity
LaChapplle,E. R. | WA-RD 008.6 | Methods of Avalanche Control in Washington Mountain Highways | 1974 |
Abstract:
This Summary Report synthesizes the work on avalanche control carried out at the University of Washington from 1970 through 1974. Five problem areas are addressed: 1. Identification of avalanche paths. 2. Description of historical frequency and size of avalanches. 3 Prediction of avalanche. 4. Identification of control methods. 5. Inclusion of control and prediction schemes in highway design and operation.
Authors:
LaChapplle,E. R., Brown,C. B., Evans,R. J.
Keywords:
avalanche, snow, decisions, weather, vegetation, creep, glide, avalanche forecasting, control, design, highway, highway design, methods, prediction, Washington
This Summary Report synthesizes the work on avalanche control carried out at the University of Washington from 1970 through 1974. Five problem areas are addressed: 1. Identification of avalanche paths. 2. Description of historical frequency and size of avalanches. 3 Prediction of avalanche. 4. Identification of control methods. 5. Inclusion of control and prediction schemes in highway design and operation.
Authors:
LaChapplle,E. R., Brown,C. B., Evans,R. J.
Keywords:
avalanche, snow, decisions, weather, vegetation, creep, glide, avalanche forecasting, control, design, highway, highway design, methods, prediction, Washington
|
Klasell,J. A. | WA-RD 018.1 | Acoustical Barrier Noise Characteristics Research Project, HR 535 HR 475 | 1974 |
Abstract:
This study was chiefly aimed at determining if a standard precast concrete median barrier placed on a highway shoulder in a fill section, would be effective in reducing highway traffic noise outside of the roadway prism. Secondly, it attacked the question of whether the current computer noise prediction program was giving accurate values.The first phase of the study consisted of collecting noise and traffic measurements in the field, first without and then with a median barrier, at two selected test sites. Next, the geometry of the test sites and field traffic data were entered into the computer program and the predicted noise levels obtained.The second phase consisted of comparing these two sets of data to determine the accuracy of the computer program and the amount of sound reduction, if any, due to the median barrier.The results indicated that the highway traffic noise was dominated by truck generated noise. It was therefore concluded that a standard median barrier will not provide a significant amount of sound reduction, outside of the roadway prism, when placed on a highway shoulder in a fill section. The results also indicated that the current computer noise prediction program will calculate noise levels that are usually higher than actually exist.
Authors:
Klasell,J. A., Butler,B. W.
Keywords:
Acoustical barrier, barrier attenuation, computer, computer program, concrete, data, ground attenuation, highway, median, median barrier, noise, Noise Levels, precast, precast concrete, prediction, program, research, roadway, traffic, traffic data, traffic noise, truck, wind, wind noise, barrier, project
This study was chiefly aimed at determining if a standard precast concrete median barrier placed on a highway shoulder in a fill section, would be effective in reducing highway traffic noise outside of the roadway prism. Secondly, it attacked the question of whether the current computer noise prediction program was giving accurate values.The first phase of the study consisted of collecting noise and traffic measurements in the field, first without and then with a median barrier, at two selected test sites. Next, the geometry of the test sites and field traffic data were entered into the computer program and the predicted noise levels obtained.The second phase consisted of comparing these two sets of data to determine the accuracy of the computer program and the amount of sound reduction, if any, due to the median barrier.The results indicated that the highway traffic noise was dominated by truck generated noise. It was therefore concluded that a standard median barrier will not provide a significant amount of sound reduction, outside of the roadway prism, when placed on a highway shoulder in a fill section. The results also indicated that the current computer noise prediction program will calculate noise levels that are usually higher than actually exist.
Authors:
Klasell,J. A., Butler,B. W.
Keywords:
Acoustical barrier, barrier attenuation, computer, computer program, concrete, data, ground attenuation, highway, median, median barrier, noise, Noise Levels, precast, precast concrete, prediction, program, research, roadway, traffic, traffic data, traffic noise, truck, wind, wind noise, barrier, project
Krukar,M. | WA-RD 015.5 | Pavement Research At WSU Volume No. 5 - Evaluation and Analysis of Results From Experimental Rings No. 1-4 1020 | 1971 |
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
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
|
Rossano,A. T. | WA-RD 012.3 | Acoustic Radar and Its Applicability To Highway Air Pollution Studies 1032 |
Abstract:
At the request of the Washington Department of Highways two studies have been conducted by a team of specialists at the University of Washington Air Resources Program to determine the applicability of the Acoustic Radar to air quality modeling to mobile sources.At the request of the Washington Department of Highways two studies have been conducted by a team of specialists at the University of Washington Air Resources Program to determine the applicability of the Acoustic Radar to air quality modeling of mobile sources. Following an exploratory investigation, a comprehensive study was undertaken in which the atmospheric structure was measured by a modified Monostatic Acoustic Radar and the derived stability conditions were compared with the commonly used Pasquill-Turner stability classes, which are based on empirical data. This comprehensive study was performed over a three month period in the fall of 1976, when an unusually persistent air stagnation existed in the study area caused by a stationary high pressure system over the entire Northwest.The Evergreen Point Floating Bridge Toll Plaza in Bellevue, Washington was selected for test location.The carbon monoxide (CO) concentrations were measured at six strategically located sampling points and then compared with the computer model predictions utilizing atmospheric stability data derived by both the Pasquill-Turner and the Radar echo methods. The results indicated that the Acoustic Radar method of determining D & E stability classes is a more realistic approach than that of the Pasquill-Turner Method. Furthermore, the Radar method can also provide continuous remote sensing and recordings of atmospheric parameters. The variation of the inversion height, as measured by the Radar echoes has shown a reasonably good correlation with the variation of the measured CO concentration.
Authors:
Rossano,A. T., Badgley,F. I., Juhasz,P. C., Bang,G., Carsey,F.
Keywords:
Acoustic Radar, air pollution, air quality, Air Quality Modeling, bridge, carbon monoxide, Carbon Monoxide Perdictions, computer, Concentrations, condition, data, floating bridge, highway, Highways, ITS, model, modeling, prediction, pressure, program, quality, remote sensing, Remote Sensing Atmospheric Structur, sampling, stability, Transportation Pollutio, Washington
At the request of the Washington Department of Highways two studies have been conducted by a team of specialists at the University of Washington Air Resources Program to determine the applicability of the Acoustic Radar to air quality modeling to mobile sources.At the request of the Washington Department of Highways two studies have been conducted by a team of specialists at the University of Washington Air Resources Program to determine the applicability of the Acoustic Radar to air quality modeling of mobile sources. Following an exploratory investigation, a comprehensive study was undertaken in which the atmospheric structure was measured by a modified Monostatic Acoustic Radar and the derived stability conditions were compared with the commonly used Pasquill-Turner stability classes, which are based on empirical data. This comprehensive study was performed over a three month period in the fall of 1976, when an unusually persistent air stagnation existed in the study area caused by a stationary high pressure system over the entire Northwest.The Evergreen Point Floating Bridge Toll Plaza in Bellevue, Washington was selected for test location.The carbon monoxide (CO) concentrations were measured at six strategically located sampling points and then compared with the computer model predictions utilizing atmospheric stability data derived by both the Pasquill-Turner and the Radar echo methods. The results indicated that the Acoustic Radar method of determining D & E stability classes is a more realistic approach than that of the Pasquill-Turner Method. Furthermore, the Radar method can also provide continuous remote sensing and recordings of atmospheric parameters. The variation of the inversion height, as measured by the Radar echoes has shown a reasonably good correlation with the variation of the measured CO concentration.
Authors:
Rossano,A. T., Badgley,F. I., Juhasz,P. C., Bang,G., Carsey,F.
Keywords:
Acoustic Radar, air pollution, air quality, Air Quality Modeling, bridge, carbon monoxide, Carbon Monoxide Perdictions, computer, Concentrations, condition, data, floating bridge, highway, Highways, ITS, model, modeling, prediction, pressure, program, quality, remote sensing, Remote Sensing Atmospheric Structur, sampling, stability, Transportation Pollutio, Washington
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