Transportation Intelligence

Volume 7 Number 3

June 2009

Safety

Administration

Traffic Control

Feedback

Safety
Safe Integration of Electric Low Speed Vehicles on Ontario's Roads in Mixed Traffic
An eight-week study was conducted by NRC-CSTT to identify the risks associated with the introduction of Low Speed Vehicles (LSVs) on Ontario’s public roads in mixed traffic. Based on the survey of U.S. and Canadian jurisdictions, information gathered from publicly available sources, reports from subject matter experts and data analysis, NRC-CSTT identified risks and recommended mitigating strategies as they relate to safely integrating LSVs into mixed traffic on Ontario’s public roads. Mitigating strategies for risks associated with LSV safety features, additional road infrastructure enhancements and initiatives to increase public awareness of LSV features have also been proposed. (National Research Council of Canada report CSTT-HVC-CTR-074, November 24, 2008, 221 p.)

Winter Maintenance
Training Supervisors in Winter Maintenance Operations: A Survey of State Department of Transportation Practices, Training Tools, and Programs
Supervisors in winter maintenance operations are often promoted from within the ranks of operators. As they prepare to take on management responsibilities, new supervisors may require additional training. The Clear Roads winter maintenance pooled fund is interested in identifying key elements of a curriculum to train winter maintenance operations supervisors and has asked us to gather information about supervisor training programs used by state DOTs. Information about training tools and programs available through national associations and commercial organizations would also be useful. (Wisconsin Department of Transportation Synthesis Report, 4 May 2009, 24 p.)

Safety

Design and Evaluation of Effective Crosswalk Illumination
Pedestrian-related crashes are a common cause of roadway fatalities, and reduced visibility at night is a probable contributor to pedestrian injuries and death. The purpose of the present study was to systematically evaluate different approaches to lighting at pedestrian crosswalks to improve pedestrian visibility and detection. The project team conducted a series of photometrically accurate lighting simulations in order to assess the visual conditions resulting from different lighting configurations, and assessed the economics (initial cost, and electricity and maintenance costs) of each system evaluated. Finally, the most promising lighting configuration was field tested during a one-night demonstration at an intersection in New Jersey. (New Jersey Department of Transportation Report FHWA-NJ-2009-031, March 2009, 60 p.)

Influence of Roadway Surface Discontinuities on Safety
This circular is an update to a 1983 report of the same title. Issues addressed in this updated state-of-the-art report include hydroplaning, holes and bumps, edge conditions, and positive effects of road surface discontinuities. (Transportation Research Board Circular E-C134, May 2009, 88 p.)

Lighting and Vegetation for Energy-Efficient and Safe Roadway Travel
The objective of the present study was to identify and evaluate promising approaches to incorporating lighting and vegetation along roadways with the purpose of identifying the most promising application that could be incorporated into a demonstration project. The project team reviewed existing lighting, roadway delineation and vegetation practices in New York State and elsewhere to identify promising approaches combining these elements for roadway applications. Through a series of lighting simulations, the visibility of relevant objects along each of several roadway applications (roundabouts, curved exit ramps, and urban boulevards) were compared when they were illuminated using conventional roadway lighting without inclusion of vegetation as a visual element, and when they were designed with both lighting and vegetation as an integrated system. Economic analyses and energy use comparisons were also performed to identify the relative impact of the new lighting and vegetation approaches. (New York State Department of Transportation report, May 2009, 74 p.)

Relationship between Road Geometry, Observed Travel Speed, and Rural Accidents
This study has sought to investigate the relationship between road geometry, observed travel speed and crashes, using data collected on six sections of State Highway in 2005–2006. Using these data, the research has investigated the relationship between road geometry and the speed choices made by the sample drivers. Based on ‘calibration’ data from a series of traffic speed classifiers, these investigations have been extended to consider the expected 85th percentile speed choice of the wider population. The speed at which drivers chose to negotiate a particular curve is more strongly related to the radius of the curve than to the design speed. However, in general, the radius does not begin to effect negotiation speed until the curve radii fall below 300 m. (Land Transport New Zealand Report 371, 2009, 72 p.)

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Urban

Resident Perceptions of Bicycle Boulevards: A SE Salmon Street Case Study
Very little is known about the impacts of bicycle boulevard designation on residential neighborhoods. For example, do Bicycle Boulevards have a positive or negative impact on home values? Do they encourage residents to cycle more? How large of a factor does the presence of a Bicycle Boulevard play into people’s decision to move to the neighborhood? Better understanding how communities react to bicycle boulevard designation would be helpful to planners seeking to improve and expand the existing bicycle network within their respective communities. (Initiative for Bicycle and Pedestrian Innovation at Portland State University report, 10 December 2008, 38 p.)

Effects of On-Street Parking on Cyclist Route Choice and the Operational Behavior of Cyclists and Motorists
Because of the serious societal, environmental, economic, and public health problems associated with motorized transportation, there is increased interest in encouraging non-motorized modes of travel. The current study contributes toward this objective in two ways. First, it evaluates the operational impacts of bicycling adjacent to on-street parking. Second, it identifies the importance of attributes influencing bicyclists’ route choice preferences. The importance of evaluating both operations and individual preferences at the same time is the interrelationship between the two; poorly designed roadways may encourage cyclists to leave designated bicycle routes. Operationally, this study examines field data that was collected in Austin, Houston, and San Antonio and resulted in over 6,400 observations of motorists and/or cyclists adjacent to on-street parking. (University of Texas at Austin Center for Transportation Research Report, April 2009, 121 p.)

FTA Low-Speed Urban Maglev Research Program – Lessons Learned
In 1999, the Federal Transit Administration initiated the Low-Speed Urban Magnetic Levitation (UML) Program to develop magnetic levitation technology that offers a cost effective, reliable, and environmentally sound transit option for urban mass transportation in the United States. The lessons learned in this report have been captured through a multi-faceted assessment of general project impressions, project execution, project conclusions and deliverables, project team performance, stakeholder participation, risk management, and project communications. The assessments are drawn from project documentation, discussions with the performing teams, and direct experience with the five UML projects. (US Federal Transit Administration report FTA-DC-26-7260-2009.01, March 2009, 55 p.)

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Administration

Quantifying the Benefits of Road Safety Audits
Although the Road Safety Audit (RSA) process is gaining widespread application throughout North America, little is understood about the net benefits being derived for design-build projects. A better understanding of collision reduction and mitigation is necessary to allow an objective economic evaluation of the RSA process. This study attempted to quantify the benefits of RSAs through a retrospective case study of the first major design-build RSA that was conducted in Canada – the Fredericton-Moncton Highway project. (University of New Brunswick Transportation Group Paper, 2008, 11 p.)

Streamlining and Integrating Right-of-Way and Utility Processes With Planning, Environmental, and Design Processes in Australia and Canada
Many transportation projects require acquisition of land and accommodation of utility facilities in the right-of-way. The Federal Highway Administration, American Association of State Highway andTransportation Officials, and National Cooperative Highway Research Program sponsored a scanning study of Australia and Canada to learn about innovative practices for right-of-way and utility processes. The study complemented a 2000 study of European countries. The scan team identified nine priorities for U.S. implementation. (US Federal Highway Administration Report FHWA-PL-09-011, June 2009, 80 p.)

Asset Management Data Collection for Supporting Decision Processes
In order to support Asset Management, agencies must collect, store, manage, and analyze large amounts of data in an effective and efficient manner. Although agencies have strongly emphasized collecting and integrating data, little effort has gone into linking the data collection to the agencies’ decision-making processes. The objective of the investigation discussed in this report was to investigate how State departments of transportation (DOTs) are linking their data collection policies, standards, and practices to their Asset Management decision-making processes, especially for project selection. This decisionmaking level functions as an intermediate stage between high-level strategic decisions and low-level, project-specific decisions. (US Federal Highway Administration report, March 2009, 97 p.)

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Traffic Control

Traffic Calming on Main Roads Through Rural Communities
Speed management is a significant challenge for most communities in the United States. This is particularly true for small, rural communities where the main roadway through the town serves a dual role. Outside the town, the roadway provides high-speed travel over long distances; within the built-up area, however, the same roadway accommodates local access, pedestrians of all ages, on-street parking, bicycles, and the many other features unique to the character of a community. This convergence of roadway purposes presents both an enforcement challenge for the community and a potential safety problem for the public. Traffic calming has been evaluated and used extensively within low-speed urban areas in the United States but less so in rural areas where driver expectations and traffic characteristics are different. (US Federal Highway Administration TechBrief, February 2009, 16 p.)

Effectiveness of Dynamic Messaging on Driver Behavior for Late Merge Lane Road Closures
Efforts to improve safety and traffic flow through merge areas on high volume/high speed roadways have included early merge and late merge concepts and several studies of the effectiveness of these concepts, many using Intelligent Transportation Systems for implementation. The Iowa Department of Transportation (Iowa DOT) planned to employ a system of dynamic message signs (DMS) to enhance standard temporary traffic control for lane closures and traffic merges at two bridge construction projects in western Iowa (Adair County and Cass County counties) on I-80 during the 2008 construction season. To evaluate the DMS system’s effectiveness for impacting driver merging actions, the Iowa DOT contracted with Iowa State University’s Center for Transportation Research and Education to perform the evaluation and make recommendations for future use of this system based on the results. (Iowa State University Center for Transportation Research and Education report 08-327, March 2009, 99 p.)

Optimization of Speed Control Hump Profiles
In this study, the goal attainment method was implemented for the optimization of speed control hump profiles. Basic dimensions for a number of hump profile functions are optimized for single vehicles classified in five categories and for a specialized distribution of these vehicles. Objective functions are selected as combinations of the longitudinal and vertical acceleration components at pre-specified points on the vehicle body. The main objective is to minimize vehicle response functions below the hump crossing speed limit and to maximize them above the speed limit. Typical characteristics of a series of of two axle vehicles, described by the half car model, are used and the performances of various hump profiles are assessed. (Journal of Transportation Engineering, May 2009, pp. 260-269.) (To obtain this artucle, please contact the TIS.)

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