Time-Dependent Expressions for Delay, Stop Rate and Queue Length at Traffic Signals

Abstract

New expressions are presented for delay, stop rate and queue length at traffic signals operating in a fixed-time mode for flow conditions which last for a finite period of time. The emphasis is on the use of the overflow queue concept which facilitates a better understanding of the transition from undersaturated conditions to oversaturated conditions. Each one of the new expressions for delay, stop rate and queue length is presented in a simple form consisting of a uniform component and an overflow component. The latter is an explicit function of the average overflow queue. Transition functions for the average overflow queues at isolated as well as co-ordinated signals are presented.