Evaluation of signal timing and parking strategies on a signalized urban arterial

Abstract

A computer model for traffic signal coordination, TRANSYT-7F, was applied to a signalized urban arterial in the city of Thunder Bay. The purpose of this application was to develop an optimal coordinated signal timing for the arterial. The study arterial consisted of five intersections and extended over a distance of 1.2 km. Observed traffic volumes and their direction of movement were collected during an afternoon peak period (4:00 p.m. to 5:00 p.m.) in September 1983. Data on existing physical configuration and signal system characteristics were also collected and modelled for input to TRANSYT-7F. Seven improvement strategies concerning changes in the existing signal system and regulatory conditions were evaluated and compared to existing conditions (do-nothing). Several measures of effectiveness generated by TRANSYT-7F were used as the basis for evaluation, which included travel time in the system, delay, fuel consumption, and a performance index, which is a function of delay encountered in the system and the number of stops.The results showed that the best strategy was to implement a common cycle of 52 s for the entire system. This is opposed to the existing 80 s network-wide cycle length. This strategy optimized the corridor with parking prohibitions on both sides of the arterial, and two phases per cycle at all intersections. The best strategy improved all measures of effectiveness. In particular, a reduction in the magnitude of 36% in the performance index was observed, along with a predicted decrease in fuel consumption of 21%. Key words: signal timing, coordination, arterial, traffic, management, parking, evaluation, computer model, delay, fuel consumption.