摘要 :
The operators and maintainers of highway networks are facing increasing demands and customer expectations regarding mobility and transportation safety during inclement weather, while confronting budget and staffing constraints and...
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The operators and maintainers of highway networks are facing increasing demands and customer expectations regarding mobility and transportation safety during inclement weather, while confronting budget and staffing constraints and environmental challenges related to chemical and material usage. It is desirable to use the most recent advances and best practices to improve the effectiveness and efficiency of winter operations, optimize material usage, and reduce annual spending, corrosion and environmental impacts. Determining the benefits and costs of various winter maintenance practices, equipment and operations is a difficult and time consuming proposal for winter maintenance managers. This project developed a toolkit which would facilitate such a benefit-cost analysis to address this need. The toolkit items included anti-icing, deicing, carbide blades, front plows, underbody plows, zero velocity spreaders, Maintenance Decision Support Systems, Automatic Vehicle Location and Geographic Positioning Systems, Road Weather Information Systems, and mobile pavement or air/pavement temperature sensors. The developed toolkit is a website which receives parameter inputs from a user and generates a benefit-cost ratio for the item of interest.
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摘要 :
The Winter Performance Index is a method of quantifying winter storm events and the DOT’s response to them. It is a valuable tool for evaluating the State’s maintenance practices, performing post-storm analysis, training mainten...
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The Winter Performance Index is a method of quantifying winter storm events and the DOT’s response to them. It is a valuable tool for evaluating the State’s maintenance practices, performing post-storm analysis, training maintenance personnel, and identifying potential areas of cost savings and improved performance. The Winter Performance Index will be available for continued use in Region 4 through the end of the 2015-16 winter season. If the Index is determined to be a valuable tool, CDOT can choose to expand access statewide beyond the 2015-16 season.
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摘要 :
During periods of wet weather, particularly when it is also cold, asphalt pavements develop potholes which cannot be immediately repaired with conventional asphalt materials. Materials are needed which can be successfully used to ...
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During periods of wet weather, particularly when it is also cold, asphalt pavements develop potholes which cannot be immediately repaired with conventional asphalt materials. Materials are needed which can be successfully used to repair asphalt pavements in wet, or cold and wet, weather. The materials should be of reasonable cost and have at least a moderate life of one to three years. The work described in this volume is a summary of the research done on fly ash as part of the study.
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The five papers in this report deal with the following areas: maintenance of reflective signs; new-old cost-cutting concept in traffic marking; collection of work-zone accident data; field evaluation of snowplowable pavement marke...
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The five papers in this report deal with the following areas: maintenance of reflective signs; new-old cost-cutting concept in traffic marking; collection of work-zone accident data; field evaluation of snowplowable pavement markers; and, evaluation of the effect of natural brine deicing agents on pavement materials.
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Contents: Fostering innovation in the strategic highway research program; Efficient personnel management for winter highway maintenance; Natural brine as an additive to abrasive materials and deicing salts; Grygla snow and ice ser...
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Contents: Fostering innovation in the strategic highway research program; Efficient personnel management for winter highway maintenance; Natural brine as an additive to abrasive materials and deicing salts; Grygla snow and ice service level for low-volume highways; Formates as alternative deicers; Risk of vehicle-tree accidents and management of roadside trees; Controlling seedheads in tall fescue with herbicides; An analysis of design features in mitigating highway construction impacts on streams; Smooth cordgrass establishment in tidal wetlands; Concrete slabs and blocks for car park paving; and The Blue Ridge Parkway Study: landscape management-history, classification, simulation, and evaluation.
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During winter 1980/81 two roads, where chemical treatment (salting) had previously been used to prevent skidding, were given only mechanical anti-skid treatment (sanding). One of the roads has wide shoulders and straight alignment...
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During winter 1980/81 two roads, where chemical treatment (salting) had previously been used to prevent skidding, were given only mechanical anti-skid treatment (sanding). One of the roads has wide shoulders and straight alignment with no gradients. The other has no shoulders and follows a twisting course although this road also has no gradients. Traffic on the roads is mainly local commuter traffic and road users were informed about the experiments both through the local mass media and by signs along the test roads. The effects on road condition, friction and traffic speed were studied on the unsalted test roads and on nearby salted control roads. During winter 1979/80 corresponding studies were made on the same roads. The results from these are used as reference data.
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摘要 :
The main objective of a snow and ice control operation strategy is to bring the road surface to a safe state for the driving public within a reasonable period of time. An important factor in this operation is the ability to determ...
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The main objective of a snow and ice control operation strategy is to bring the road surface to a safe state for the driving public within a reasonable period of time. An important factor in this operation is the ability to determine the optimum amount of chemicals that need to be applied to achieve a safe surface condition. Over the past several years, personnel at many highway agencies in Europe, Japan, and the United States have come to believe that surface friction measurements may form the basis for improved winter maintenance operations and mobility. In light of all these factors, NCHRP initiated Project 6-14 to evaluate the feasibility of using friction indicators as tools for improving winter maintenance operations and mobility. Friction measurements for winter maintenance have been used in experimental research in the United States and in operational application (without sufficient supporting data) in some Scandinavian countries, while analytical and theoretical work, including the use of a neural network to predict friction from other data such as weather, traffic, and pavement condition, has been conducted in Japan. This study has found that the use of friction measurements to improve winter maintenance operations and mobility is feasible (especially when deceleration devices are used), but devices with an extra wheel may not represent a practical solution to friction measurement.
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This report documents the research project "Research and Development for Avalanche Sensing". The primary goal of this research was to develop avalanche sensing and detection for a key Caltrans District 10 avalanche zone.
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Highway agencies spend millions of dollars to ensure safe and efficient winter travel. However, the effectiveness of winter-weather maintenance practices on safety and mobility are somewhat difficult to quantify. Safety and Mobil...
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Highway agencies spend millions of dollars to ensure safe and efficient winter travel. However, the effectiveness of winter-weather maintenance practices on safety and mobility are somewhat difficult to quantify. Safety and Mobility Impacts of Winter Weather - Phase 1 investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter-weather conditions. In Phase 2, three Iowa Department of Transportation (DOT) high-priority sites were evaluated and realistic maintenance and operations mitigation strategies were also identified. In this project, site prioritization techniques for identifying roadway segments with the potential for safety improvements related to winter-weather crashes, were developed through traditional na?ve statistical methods by using raw crash data for seven winter seasons and previously developed metrics. Additionally, crash frequency models were developed using integrated crash data for four winter seasons, with the objective of identifying factors that affect crash frequency during winter seasons and screening roadway segments using the empirical Bayes technique. Based on these prioritization techniques, 11 sites were identified and analyzed in conjunction with input from Iowa DOT district maintenance managers and snowplow operators and the Iowa DOT Road Weather Information System (RWIS) coordinator.
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Safety and Mobility Impacts of Winter Weather - Phase 1 investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter weather conditions. The primary objective was to develop several preli...
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Safety and Mobility Impacts of Winter Weather - Phase 1 investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter weather conditions. The primary objective was to develop several preliminary means for the Iowa Department of Transportation (DOT) to identify locations of possible interest systematically with respect to winter weather–related safety performance based on crash history. Specifically, four metrics were developed to assist in identifying possible habitual winter weather-related crash sites on state-maintained rural highways in Iowa. In addition, the current state of practice, for both domestic and international highway agency practices, regarding integration of traffic safety- and mobility-related data into winter maintenance activities and performance measures was investigated. In Phase 2, a combination of the Phase 1 results and Iowa DOT maintenance field staff input were employed to evaluate three Iowa DOT high-priority sites. Winter-weather crash-mitigation analysis procedures were developed and applied for three sites. Realistic maintenance and operations mitigation strategies were also identified.
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