TITLE:
A Quantitative Approach for Timing the Pedestrian Walk Interval
AUTHORS:
Abdullah Jalal Nafakh, Darcy Michael Bullock, Jon Douglas Fricker
KEYWORDS:
Pedestrian Start-Up Time, Walk Interval, Pedestrian Phasing
JOURNAL NAME:
Journal of Transportation Technologies,
Vol.12 No.4,
September
30,
2022
ABSTRACT: At a typical signalized intersection, the pedestrian phase consists of a
walk interval and a change/clearance interval, during which pedestrians are
given the right of way. The walk interval is intended to allow pedestrians to
exit the curb ramp and enter the crosswalk. The clearance interval will enable
them to cross entirely to the other side of
the road. Unfortunately, the literature is quite vague on how long the walk
interval should be and provides values ranging from 4 to 15 seconds
based on qualitative pedestrian demand ranging from Negligible to High. To
provide some quantitative guidance for walk interval selection, this paper
reports on a study that collected 1,500 pedestrian movement data from 12
signalized intersections with varying pedestrian demand, pedestrian storage
areas, and pedestrian push-button locations. The data was used to propose a
quantitative model for designers to select the appropriate walk interval.
Specifically, this paper seeks to add values to the Traffic Operations Handbook
walk-interval guidelines as to how many pedestrians are considered “negligible
volume” and can be accommodated by the 4 second minimum time, how many
pedestrians are considered “typical volume” and require 7 to 10 seconds, and
how many pedestrians are considered “high volume” and require 10 to 15 seconds,
or perhaps longer. In addition to examining pedestrian demand, this paper looks
at the impact of storage areas and pedestrian push-button location on
pedestrian start-up time and, consequently, an appropriate walk interval.