IMPLEMENTATION GUIDELINES FOR RETIMING DIAMOND INTERCHANGES. INTERIM REPORT

This document provides guidelines and procedures for the retiming of diamond interchanges, including procedures for data collection, and the types and amount of data to be collected; the analytical procedures and software packages that are available for signal retiming projects; and examples of step-by-step applications for each type of signal timing project. Section One, Introduction, provides background information and discusses how to determine if a diamond interchange should be retimed. Section Two, Diamond Interchanges, discusses the characteristics of a diamond interchange, including the types of phasing, controllers, measures of effectiveness, and signal timing methods. Section Three, Data Requirements, discusses the procedures and requirements for data collection at a diamond interchange. Section Four, Evaluation, provides information needed for the simulation of existing interchange operations, including the use of currently available software programs. Section Five, Optimization, provides the guidelines to optimize timings at a typical diamond interchange. Section Six, Implementation, explains the interpretation of optimized signal plans and implementation in the field. Section Seven, Documentation, explains how the benefits of signal retiming can be calculated, and provides examples of possible benefits.