Transportation Intelligence

Volume 6 Number 5

October 2008

Environment
Pavements
Traffic Control
Safety
Feedback

Safety
Face off - tunnel fire detection systems
In support of the Fire Protection Research Foundation's international research project to ascertain the performance of tunnel evacuation and firefighting procedures, the National Research Council of Canada (NRC) investigated the laboratory performance of detection systems under minimal and longitudinal airflow conditions and conducted tests in the Carré-Viger Tunnel in Montréal. Related testing was done in the Lincoln Tunnel in New York City. The project studied nine fire detection systems installed in the laboratory tunnel facility and in the two tunnels for detection system response time, ability to locate and monitor a fire, and the effect of the tunnel environment. (National Research Council of Canada report NRCC-50558, 2008, 8 p.)

Urban
Multimodal Level of Service Analysis for Urban Streets
TRB’s National Cooperative Highway Research Program (NCHRP) Report 616: Multimodal Level of Service Analysis for Urban Streets explores a method for assessing how well an urban street serves the needs of all of its users. The method for evaluating the multimodal level of service (MMLOS) estimates the auto, bus, bicycle, and pedestrian level of service on an urban street using a combination of readily available data and data normally gathered by an agency to assess auto and transit level of service. The MMLOS user’s guide was published as NCHRP Web-Only Document 128 (http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_w128.pdf). (TRB's National Cooperative Highway Research Program Report 616, 2008, 122 p.)

Structures
Location Aware Tools for Inspection of Fixed Structures
This report examines the feasibility and desirable features of a location-aware portable information base to support bridge inspection that would remove the need for the inspector to take construction drawings to the site. It describes the prior art of systems for visual inspection of structures, provides an overview of enabling technologies, presents three alternative conceptual designs of a location-aware portable inspection system, and discusses the limitations of location-finding technologies. (National Research Council of Canada Research Report RR-260, July 2008, 32 p.)

Specification and Design of Fiber Reinforced Bridge Deck Forms for Use on Wide Flange T-Girders
Wide-flanged concrete girders are increasingly being used for highway bridges in Wisconsin. These girders are closely spaced and have very small clear gaps between the girder flanges making conventional plywood formwork difficult to install and uneconomical. Non-structural, non-metallic, stay-in-place (SIP) formwork may be more economical than conventional formwork in these situations; however a specification for their design and use in Wisconsin does not exist at this time. The objective of this research was to understand the state of the art of non-metallic SIP forms and to develop design guidelines and performance specifications that can be used locally for the construction of highway bridge decks. (Wisconsin Highway Research Program Report 07-10, October 2007, 144 p.)

Environment

Reducing Greenhouse Gas Emissions From Transportation Sources in Minnesota
The 2007 Minnesota Next Generation Energy Act established goals for reducing statewide greenhouse gas (GHG) emissions. This report investigates strategies for meeting those reductions in Minnesota's transportation sector. The study focuses on three types of emission-reduction strategies: those that improve vehicle fuel economy, those that reduce the number of vehicle-miles travelled, and others that decrease the carbon content of fuel. An appendix to the report is available online at http://www.cts.umn.edu/pdf/CTS-08-10_appendix.pdf (University of Minnesota Center for Transportation Studies Report CTS 08-10, June 2008, 60p.+apps.)

Integrating Climate Change into the Transportation Planning Process
The objective of this study is to advance the practice and application of transportation planning among state, regional, and local transportation planning agencies to successfully meet growing concerns about the relationship between transportation and climate change. This report explores the possibilities for integrating climate change considerations into long range transportation planning at state DOTs and MPOs. The report reviews the experience of a number of DOTs and MPOs that are already incorporating climate change into their transportation planning processes and identifies their successes as well as challenges faced by these agencies. (US Federal Highway Administration, July 2008, 59 p.)

Evaluation of the Use and Effectiveness of Wildlife Crossings
This report documents the development of an interactive, web-based decision guide protocol for the selection, configuration, and location of wildlife crossings. For the first time, transportation planners and designers and wildlife ecologists have access to clearly written, structured guidelines to help reduce loss of property and life due to wildlife–vehicle collisions, while protecting wildlife and their habitat. The guidelines were based on goals and needs identified and prioritized by transportation professionals from across North America, and developed using the results of five parallel scientific studies. The decision tool as outlined in the report can be found on the web at http://www.wildlifeandroads.org or http://environment.transportation.org/environmental_issues/wildlife_roads/decision_guide/manual. (TRB National Cooperative Highway Research Program (NCHRP) Report 615, 2008, 174 p.)

Stream Simulation: An Ecological Approach to Providing Passage for Aquatic Organisms at Road-Stream Crossings
This is a guide to stream simulation—a method for designing and building road-stream crossings intended to permit free and unrestricted movements of any aquatic species. The guide aims to help national forests achieve their goal of maintaining the physical and biological integrity of the stream systems they manage, including existing populations of fish and other wildlife species. Habitat fragmentation is an important factor contributing to population declines of many fish, and crossing structures that are barriers are a large part of the problem. Stream simulation provides continuity through crossing structures, allowing all aquatic species present to move freely through them to access habitats, avoid adverse conditions, and seek food and mates. Stream simulation applies to crossing structures on any transportation network, including roads, trails, and railroads. For brevity, the guide refers to all of these types of transportation infrastructure as roads. (US Forest Service Report, May 2008, 646 p.)

Environmental Guide for Noise
The Ontario Ministry of Transportation (MTO) Environmental Guide for Noise (referred to as the Noise Guide) was developed to provide guidance for MTO personnel and consultants in the analysis of highway noise and its effects. It replaces the Environmental Office Manual – Technical Areas – Noise, EO-V-1000-00 (May 1992). (Ontario Ministry of Transportation Report, October 2006, 53 p.)

Tire/Pavement and Environmental Traffic Noise Research Study Interim Report - 2006 Testing
This research study on tire-pavement noise is being conducted in response to CDOT’s interest in traffic noise in general, and the tire/pavement interaction in particular. Following a rigid set of testing protocols, data is being collected on highway traffic noise characteristics along with safety and durability aspects of the associated pavements. The overall goal of this research project is to develop and execute a comprehensive, long-term study to determine if a particular pavement surface type and/or texture can be successfully used in Colorado to help satisfy FHWA noise mitigation requirements. The information included in this report represents the first in a series of four measurements to be collected over a five-year period. (Colorado DOT report CDOT-2008-2, July 2008, 147 p.)

Fourchettes de concentrations de polluants dans l'air en fonction des typologies de sites (rural, urbain, périurbain, trafic et industriel) (Air Pollutant Concentration Ranges Compared to Site Typologies (rural, urban, peri-urban, traffic and industrial))
This document determines air pollutant concentration ranges against site typologies (as defined by AASQA).It will also facilitate the interpretation of measurement campaign results. The concentration ranges described could also be used as background concentrations when the AASQA do not have measurement stations or when the scope of study does not justify or allow expensive establishment of mobile measurement stations. (Rapport de CERTU, Décembre 2006, 86 p.)

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Administration

Cost-Effective Performance Measures for Travel Time Delay, Variation, and Reliability
State departments of transportation, metropolitan planning organizations, public transit authorities, and other transportation stakeholders increasingly are turning to the use of transportation system performance measures to gain and sustain public and legislative support for investments in managing, maintaining, and constructing transportation infrastructure. Measures that express congestion and mobility in terms that system users can understand and use are needed for use in systems planning, corridor development, priority programming, and operations to inform investment decisions directed at improving system performance. This report presents a framework and cost-effective methods to predict, measure, and report travel time, delay, and reliability from a customer-oriented perspective. (TRB National Cooperative Highway Research Program (NCHRP) Report 618, 2008, 79 p.)

Quality Assurance in Design-Build Projects
For transportation design-build projects, the public agency has less control over day-to-day details of the process than with more traditional approaches to project design and construction. Design-build projects, therefore, require a thorough and thoughtful approach to assuring quality in the project by the public agency. This report examines how state transportation agencies have successfully approached quality assurance for design-build, including in procurement, design, construction, and post-construction operations and maintenance. (TRB National Cooperative Highway Research Program NCHRP Synthesis, 2008, 139 p.)

Highway Infrastructure Security and Emergency Management (HIS/EM) Professional Capacity Building (PCB)
HIS/EM Professional Capacity Building was initially established as the Federal Highway Administration (FHWA) Security PCB Program. Its objective was to enhance the knowledge and understanding of security among the nation's highway workforce. In collaboration with the American Association of State Highway and Transportation Officials (AASHTO) and the US Department of Transportation Volpe Transportation Systems Center and acknowledging the natural linkage between highway infrastructure security and emergency management, the Security PCB Program was transformed into HIS/EM PCB in 2007. Concurrently the objective was expanded to also include the need for providing knowledge and understanding about emergency management to the highway workforce. This site represents a step towards meeting the expanded objective. (US Federal Highway Administration web site.)

Cost effectiveness of delineation improvements for safety
The purpose of this research was to develop a cost management tool that would assist road controlling authorities and their consultants to prioritise delineation treatments that have added safety benefits compared with standard road markings. A spreadsheet-based cost management tool was developed and then applied to a range of typical road marking situations. The delineation cost management tool is available as an Excel spreadsheet at this link: http://www.ternz.co.nz/docs/DelineationCosts.xls (Land Transport New Zealand Research Report 322, July 2007, 32 p.)

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Pavements

How to Reduce Tire-Pavement Noise: Interim Better Practices for Constructing and Texturing Concrete Pavement Surfaces
One problem that has been faced until recently is the lack of a collective understanding of what makes some concrete pavements quiet and others not. To address this in recent years, the National Concrete Pavement Technology Center (CP Tech Center) at Iowa State University has amassed the largest database so far of concrete pavement surface characteristics, including measurements of noise, texture, and friction. Nearly 1,500 test sections throughout North America and Europe have been evaluated to date.
From this, and now working under Part 3 of what is termed the Concrete Pavement Surface Characteristics Program (CPSCP), the CP Tech Center has developed an understanding of the fundamental surface properties that affect noise.
Based on this knowledge, better practices that serve to avoid those surface properties are provided herein:

  • Better practices for constructing and texturing quieter concrete pavements
  • Better practices that answer the question of how we can reduce tire-pavement noise
  • Better practices that don’t compromise the other things about the pavement that are of equal or greater importance, including safety, cost, and durability.
(Iowa State University Center for Transportation Research and Education report, July 2008, 58 p.)

Guidelines for Routine Maintenance of Concrete Pavement
This report discusses the visual identification of various distress types and introduces evaluation techniques using nondestructive testing (NDT), which are key to determining proper routine maintenance activities. According to the areas selected from the simplified checklist of visual distress types, falling weight deflectometer (FWD) for structural condition evaluation, ground penetration radar (GPR) for detecting voids below the slab and the presence of trapped water, and dynamic cone penetrometer (DCP) for estimating the in situ strength of base and subgrade soils are used to provide current information on pavement condition for selection of needed repair methods using a simple, systematic decision process. Key routine maintenances activities are categorized into five levels: performance monitoring, preservative, functional concrete pavement repair (CPR), structural CPR, and remove and replace. (Texas Transportation Institute Report 0-5821-1, July 2008, 1461 p.)

Characterising pavement surface damage caused by tyre scuffing forces
The transverse shear forces generated by multi-axle groups depends on many factors including turn geometry, vehicle type, axle weights, tyre size and configuration, suspension geometry, and the number and type of axles. This study quantifies the impact of some of these parameters on the transverse pavement shear forces or scuffing forces generated during constant low-speed turns. This study provides data on the level of peak scuffing forces generated by heavy vehicles in New Zealand, the inter-relationship between scuffing forces, directional stability, lateral load transfer, and rollover stability. This is fundamental to vehicle size and weight regulation, and to the design of pavements and turn geometry at intersections. (Land Transport New Zealand Research Report 347, 2008, 67 p.)

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Traffic Control

Transit Signal Priority Research Tools
This report presents the results of a research project that addresses Transit Signal Priority (TSP) deployment issues. The report reviews National Transportation Communications for ITS Protocol (NTCIP) 1211 Signal Control and Prioritization (SCP) standards, defines five SCP scenarios, and describes how the SCP scenarios can be applied differently based on TSP priority and operating policies. The report provides an overview of a number of TSP systems, including centralized TSP, two discrete TSP systems based on loop detection and Global Positioning System (GPS) technologies, and an Adaptive Transit Signal Priority (ATSP) system. A comparison of the different TSP deployments, and guidance on the necessary infrastructure required to implement these TSP systems, are provided. The report also discusses TSP evaluation methodologies, including recommended measures of effectiveness (MOE’s) and data required for performing a quantitative assessment. Evaluations of a number of TSP deployment sites are documented to demonstrate how the benefits of TSP to transit and the impacts of TSP to traffic operations are assessed using the recommended approaches. Finally, the report provides guidance on TSP planning and analysis methods, such as simulation and regional modeling tools. (US Department of Transportation Report, May 2008, 178 p.)

Evaluation of Chevron Markings on Freeway-to-Freeway Connector Ramps in Texas
This report presents an evaluation of the use of converging chevron pavement markings in an attempt to reduce speeds on freeway-to-freeway connector ramps. In this project, a converging chevron marking was designed and implemented on a freeway-to-freeway connector ramp in El Paso, Texas. Speed measurements were conducted at the project site in three study periods: before the implementation of chevron markings, early-after the implementation, and late after the implementation of chevron markings. Speed measurements were taken upstream of the curve, at the start of the curve, and in the middle of the curve of the connector ramp. A detailed before-after analysis of the speed data was conducted by vehicle classification, light conditions, and location along the curve. (Texas Transportation Institute Report 0-4813-2, April 2008, 112 p.)

Circulatory Markings at Double-Lane Traffic Roundabout: Comparison of Two Marking Schemes
This paper compares two types of circulatory markings at a double-lane traffic roundabout: the concentric marking scheme and the Alberta marking scheme. The effects of these two marking schemes on drivers' lane choice behavior, delay, and safety, are compared based on data collected from before and after field surveys over a period of 2 years. The results showed that the Alberta marking scheme could better balance the traffic flows on the two circulatory lanes, resulting in higher performance levels. (Journal of Transportation Engineering, September 2008, pp. 378-88)(To obtain a copy of this item, please contact the TIS.)

Signalized Intersection Performance Measures for Operations Decision-Making
This feature illustrates how Highway Capacity Manual concepts can be integrated with traffic signal system detection and controller status information to provide real-time performance measures characterizing the operation of a coordinated traffic signal system, and discusses how these performance measures can be extended to include other modes. (ITE Journal, August 2008, pp. 20-23)(To obtain a copy of this item, please contact the TIS.)

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Safety

Safety Research on Highway Infrastructure and Operations: Improving Priorities, Coordination, and Quality
The Transportation Research Board (TRB) convened an expert committee to provide an independent review and assessment of the processes currently used to establish research priorities and to coordinate research activities in the area of highway infrastructure and operations safety. The committee was also charged with recommending an efficient and effective research priority-setting and coordination process and with commenting on strategies to improve research quality. The committee’s work built on the results of earlier initiatives by the National Highway Research and Technology Partnership, FHWA, and others aimed at bringing together the members of the diverse and decentralized highway safety research community. The committee proposes the creation of an independent scientific advisory committee (SAC) composed primarily of experienced safety program managers and knowledgeable researchers. The SAC would be charged with (a) developing a transparent process for identifying and prioritizing research needs and opportunities in highway safety, with emphasis on infrastructure and operations, and (b) using the process developed to recommend a national research agenda focused on highway infrastructure and operations safety. (Transportation Research Board Special Report 292, 2008, 169 p.)

Guidance for Implementation of the AASHTO Strategic Highway Safety Plan: Safety Data and Analysis in Developing Emphasis Area Plans
This guide specifically addresses highway safety data, an emphasis area under the Management category in AASHTO’s Strategic Highway Safety Plan, and was developed to aid highway safety analysts in using the other implementation guides to make decisions about how to appropriately allocate safety funds to get the best results. (TRB's National Cooperative Highway Research Program (NCHRP) Report 500, Vol. 21, 2008, 107 p.)

Surrogate Safety Assessment Model and Validation: Final Report
Safety of traffic facilities is most often measured by counting the number (and severity) of crashes that occur. It is not possible to apply such a measurement technique to traffic facility designs that have not yet been built or deployed in the real world. This project has resulted in the development of a software tool for deriving surrogate safety measures for traffic facilities from data output by traffic simulation models. By comparing one simulated design case with another, this software allows an analyst to make statistical judgments about the relative safety of the two designs. The software tool and user manual (FHWA-HRT- 08-050) are available to the public at no cost from FHWA. (US Federal Highway Administration report FHWA-HRT-08-051, June 2008, 324 p.)

Pedestrian Safety Prediction Methodology
The objective of the work under Phase III of Project 17-26, as presented in this report, is to develop a methodology for quantifying the pedestrian safety effects related to existing site characteristics and/or proposed improvements on urban and suburban arterials. The scope of the Phase III pedestrian safety methodology includes signalized intersections and roadway segments between intersections, but does not include unsignalized intersections. (TRB National Cooperative Highway Research Program Web-Only Document 129, 2008, 76 p.)

Model Minimum Uniform Crash Criteria: Updated Third Edition
The purpose of the Model Minimum Uniform Crash Criteria (MMUCC) is to provide a dataset for describing crashes of motor vehicles in transport on a roadway that will generate the information necessary to improve highway safety within each State and nationally. MMUCC represents a voluntary and collaborative effort to generate uniform crash data that are accurate, reliable and credible for data-driven highway safety decisions within a State, between States, and at the national level. MMUCC recommends voluntary implementation of a “minimum set” of standardized data elements to promote comparability of data within the highway safety community. It serves as a foundation for State crash data systems. (US Department of Transportation and Governors Highway Safety Association guideline, 2008, 152 p.)

Older Road Users
In March 2008, a team of nine transportation safety, traffic engineering, and human factors experts from the United States (U.S.) visited Australia and Japan to assess and evaluate infrastructure improvements designed to aid older road users. The scan tour members sought policy options and initiatives regarding transportation system planning, operations, and design as they relate to older road users. The group met with state and federal government transportation officials, University research centers, and staff from motorists clubs and other non-governmental organizations interested in the mobility of older people. While the focus of the scan was on infrastructure improvements, the team also learned about new policies for older road user training, assessment, and licensing. In addition, general road safety programs were discussed with all agencies visited. (US Federal Highway Administration International Scanning Program Summary Report, 17 April 2008, 23 p.)

Effectiveness and Safety of Traffic and Non-Traffic Related Messages Presented on Changeable Message Signs - Phase II
In Phase II of this investigation, we used a fully interactive PC-based STISIM driving simulator, to conduct two experiments which were similar to experiments in Phase I. The participants were 120 licensed drivers from three age groups—18-24, 32-47, and 55-65 years old—who drove, in free flow traffic, for approximately 20 miles on a four-lane freeway before encountering target messages on Changeable Message Signs (CMSs). The Phase II CMS messages were clearer and less complex than those used in Phase I. Some participants reduced speed on approaching the CMSs, suggesting similar reductions could occur in real world driving in free flow conditions. We conducted a survey which showed drivers think it is very useful to have information about traffic problems and roadway maintenance schedules on CMSs. Also, we analyzed real-world traffic speed data obtained when CMS messages were deployed. Finally, we conducted observations at Mn/DOT’s Regional Transportation Management Center (RTMC), focusing on the decision-making processes involved when traffic-related CMS messages are deployed. (Minnesota DoT Report MN/RC-2008-27, August 2008, 84 p.)

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