Citation

Abrams CM, Smith SA. Transp. Res. Rec. 1977; 629: 1-6.

Copyright

(Copyright © 1977, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

This paper presents a methodology for selecting alternate schemes for pedestrian signal phasing. The types of pedestrian phasing studied include (a) combined pedestrian-vehicle interval, (b) early release of pedestrians with respect to vehicles, (c) late release of pedestrians with respect to vehicles, and (d) scramble timing. Each alternative is weighed in terms of its impact on the safety of the pedestrian and on the delay to both pedestrians and vehicles. The results of the study indicate that the combined pedestrian-vehicle interval will almost always minimize overall pedestrian and vehicle delay. The only exception occurs for the case in which a pedestrian-vehicle conflict causes long queues of vehicles to form in a right-turning lane (or left-turning lane on a one-way street). In that case, the use of late release or scramble timing is preferable. Scramble timing is capable of increasing pedestrian safety by completely separating pedestrian and vehicular movements; however, this benefit is canceled if pedestrian compliance is low. The early release of pedestrians does not appear to significantly improve pedestrian safety and will always increase total delay at the intersection. A methodology for selecting the phasing for given pedestrian volumes and vehicle-turning movements is presented.