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Improving Traffic Signal Management and Operations: A Basic Service Model

This report provides a guide for achieving a basic service model for traffic signal management and operations. The basic service model is based on simply stated and defensible operational objectives that consider the staffing level, expertise and priorities of the responsible agency. The report includes a Literature Review, which provides a review of the National Traffic Signal Report Card and Self-Assessment, case studies based on agency archetypes that provide an understanding of how agencies deliver traffic signal management services based on their resources and interviews with acknowledged leaders providing support for the basic service concept.

Improving Traffic Signal Operations - A Primer

Traffic congestion is a major problem in cities of all sizes. People are taking more trips, and there are more vehicles on the road. The street system is often overtaxed, causing traffic to bog down. The resulting traffic congestion is costly-motorists’ time is wasted, and the environment is harmed by pollutants emitted from idling engines. Even worse, the congestion often provokes motorists into dangerous behavior, such as running red lights, in an attempt to make up lost time.

NCHRP Synthesis 403 - Adaptive Traffic Control Systems: Domestic and Foreign State of Practice

Highway administrators, engineers, and researchers often face problems for which information already exists, either in documented form or as undocumented experience and practice. This information may be fragmented, scattered, and unevaluated. As a consequence, full knowledge of what has been learned about a problem may not be brought to bear on its solution. Costly research findings may go unused, valuable experience may be overlooked, and due consideration may not be given to recommended practices for solving or alleviating the problem.

NCHRP Synthesis 409 - Traffic Signal Retiming Practices in the United States

Highway administrators, engineers, and researchers often face problems for which information already exists, either in documented form or as undocumented experience and practice. This information may be fragmented, scattered, and unevaluated. As a consequence, full knowledge of what has been learned about a problem may not be brought to bear on its solution. Costly research findings may go unused, valuable experience may be overlooked, and due consideration may not be given to recommended practices for solving or alleviating the problem.

Signal Timing on a Shoestring

The conventional approach to signal timing optimization and field deployment requires current traffic flow data, experience with optimization models, familiarity with the signal controller hardware, and knowledge of field operations including signal timing fine-tuning. Developing new signal timing parameters for efficient traffic flow is a time-consuming and expensive undertaking. This report examines various cost-effective techniques that can be used to generate good signal timing plans that can be employed when there are insufficient financial resources to generate the plans using conventional techniques. The report identifies a general, eight-step process that leads to new signal plans: 1) Identify System Intersections; 2) Collect and Organize Existing Data; 3) Conduct a Site Survey; 4) Obtain Turning Movement Data; 5) Calculate Local Timing Parameters; 6) Identify Signal Groupings; 7) Calculate Coordination Parameters; and 8) Install and Evaluate New Plans. The report examines each of these steps and identifies procedures that can be used to minimize costs in each step. Special emphasis is placed on the costs of turning movement counts. The report develops a “tool box” of procedures and provides examples of how the tool box can be used when there is a moderate signal timing budget, when there is a modest signal timing budget, and when there is a minimum signal timing budget.

Signal Timing Under Saturated Conditions

This report provides guidance to practitioners on effective strategies to mitigate the effects of congestion at signalized intersections. The scope is limited to single intersections and does not address network-level strategies. The strategies are defined in terms of their underlying objective. Under congested conditions, traditional objectives and performance measures shift from progression and minimizing delay to maximizing throughput and managing queues. Experts were interviewed to identify the strategies and tactics they used to address congested intersections, a discussion of their methods is presented. Select strategies were studied further, particularly the belief that longer cycles are more efficient, and the effects of buses on signal timing in grid networks. The research revealed that long cycle lengths may not be more efficient at intersections where long queues starve turn lanes. In grid networks, the cycle length that is just long enough to reliably serve busses from a near-side stop was found through simulation to prevent the development of residual queues.

Signalized Intersections: Informational Guide

This report complements the American association of State Highway and Transportation Officials' (AASHTO) Strategic Highway Safety Plan to develop guidance on safety of nonsignalized and signalized intersections. The goal is to reduce the annual number of highway deaths. This guide is a comprehensive document that contains methods for evaluating the safety and operations of signalized intersections and tools to remedy deficiencies.

Traffic Control Systems Handbook

The Traffic Control Systems Handbook updates the 1996 edition (FHWA-SA-96-032). It serves as a basic reference in planning, designing and implementing traffic control systems. Specific chapters include introduction, summary of available and emerging traffic control system technology, control concepts for urban and suburban streets (traffic control parameters, descriptions of traffic control concepts and their application), a brief summary of control and management concepts for freeways, traffic detectors, local controller operation, traffic control system architectures, a brief summary of traffic control system communications, traveler information systems, the processes required for selection of a system, design and implementation, and systems management. The Handbook concludes with a discussion of ITS plans and programs.

Traffic Detector Handbook: Third Edition - Volume I

The objective of the third edition of the Traffic Detector Handbook is to provide a comprehensive reference document to aid the practicing traffic engineer, planner, or technician in selecting, designing, installing, and maintaining traffic sensors for signalized intersections and freeways. Judicious application of the concepts and procedures set forth in the Handbook should result in improved installations and operations of traffic sensors and a long-term savings of public funds.

Traffic Detector Handbook: Third Edition - Volume II

The objective of the third edition of the Traffic Detector Handbook is to provide a comprehensive reference document to aid the practicing traffic engineer, planner, or technician in selecting, designing, installing, and maintaining traffic sensors for signalized intersections and freeways. Judicious application of the concepts and procedures set forth in the Handbook should result in improved installations and operations of traffic sensors and a long-term savings of public funds.

Traffic Signal Operations and Maintenance Staffing Guidelines

This report provides a guideline to estimate the staffing and resource needs required to effectively operate and maintain traffic signal systems. The results of a survey performed under this project, as well as a review of the literature and other surveys indicated that agencies achieving a high level of signal system performance do so under a wide variety of conditions such as agency size, geography, system complexity and traffic conditions that do not adhere to the typical level of documented resource requirements. Accordingly, a set of performance-based criteria were developed to define requirements. The performance-based criteria are focused on establishing realistic and concise operations objectives and performance measures.

Traffic Signal Timing Manual

Traffic Signal Timing Manual is an 18-month effort to develop a concise, practical, user friendly and modular guide to signal timing practitioners, focusing on the principals of traffic signal timing, identifying sound timing practices, and a practical and comprehensive tabletop resource.

Traffic Signal Timing Manual

The Traffic Signal Timing Manual presents a comprehensive guide and synthesis of current practices related to traffic signal timing for signalized intersections. All the different elements of traffic signal timing, from policy and funding considerations to timing plan development, assessment, and maintenance are covered comprehensively. This manual is the culmination of research into documented practices from across North America. The Signal Timing Manual is intended to be a useful reference for a range of practitioners, including traffic engineers, signal technicians, design engineers, teacher, and university students.

 
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