Citation

Reilly WR, Gardner CC. Transp. Res. Rec. 1977; 644: 1-7.

Copyright

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

DOI

unavailable

PMID

unavailable

Abstract

This report presents our findings on a design for a simple, accurate technique for measuring vehicular delay on the approach to a signalized intersection. Precise definitions were established for four measures of performance: stopped delay, time-in-queue delay, approach delay, and percentage of vehicles stopping. Approach delay was selected as being most representative of intersection efficiency. Four manual methods using film taken at 10 intersections were tested in the laboratory. The values thus obtained were statistically compared with true values from time-lapse photography. The point sample, stopped delay procedure and the percentage of vehicles stopping method were selected as the most promising methods for practical use and were performed in the field at three sites. A user's manual for application of these two methods was produced but is not included in this report. Correction factors were developed to allow the field results to more accurately estimate that true values of stopped delay and percentage of vehicles stopping. Interrelationships among the four measures of performance were established so that approach delay could be estimated from a value for stopped time.