Traffic signals: Capacity and timing analysis : Rahmi Akcelik, Australian Road Research Board, 500 Burwood Highway, Vermont South, Victoria 3133, Australian, 1981, pp. 108, $3.50.

Abstract

Traffic signal capacity and timing analysis techniques are presented as an aid for detailed geometric and operational design of signalised intersections. The report introduces several changes to the existing methods, a basic change being from phase- related methods to movement- related methods. A critical movement identification method is presented as a procedure which automatically satisfies minimum green time constraints and allows the use of different degrees of saturation for different movements. Detailed discussions of opposed turn, lane utilisation and short lane problems are presented in the section on saturation flows. New formulae are given for predicting delay, number of stops and queue length, which are applicable to both undersaturated and oversaturated conditions, and for calculating a practical cycle time and an approximate optimum cycle time using a stop penalty parameter. The prediction of operating characteristics and calculation of signal timings for vehicle- actuated and Co- ordinated signals are discussed separately in appendices. All other aspects of this report are applicable to both fixed- time and vehicle- actuated, isolated and Co- ordinated signals. Signal design questions in general, and the question of design period in particular, are discussed and a recommended design procedure which brings together various methods described in the report is given. Numerical examples are presented to illustrate the methods described in the report (a). The isbn of the microfiche is 0 86910 019 x. This report replaces the earlier arrb publications bulletin no 4 and arr no 79 (IRRD no 234157). (TRRL)