Delay functions for different movements at a signalised intersection.

Delay at intersections constitutes a major part of travel-time in traffic networks. Traffic assignment models often assume delay at signalised intersections constant, or related to traffic volume on each intersection approach. This is because it is difficult to consider the delay as a function of traffic volumes in all intersection approaches in the traffic assignment models. Further, there is a lack of appropriate functions to measure the delay of a signalised intersection approach as a function of other traffic volumes entering the intersection. This paper uses data collected from five signalised intersections in the city of Tehran, Iran, to develop two delay functions for signalised intersections. The first model considers traffic volume of each approach as an effective parameter for estimating the delay at that approach, whilst the second model suggests considering the conflicting traffic volume to predict the delay in left-turn movements. (a) For the covering entry of this conference, please see ITRD abstract no. E217099.