Citation

Torbic D, Elefteriadou L. Transp. Res. Circular 2000; (E-C018): 336-347.

Copyright

(Copyright © 2000, U.S. National Academy of Sciences Transportation Research Board)

DOI

unavailable

PMID

unavailable

Abstract

The current version of the "Highway Capacity Manual" does not account for the impact of varying driver populations in the analysis procedures for signalized intersections. This study analyzes the difference in saturation flow rates during different times of the day and days of the week. It is hypothesized that traffic streams exhibit different operational characteristics during different times of the day and days of the week due to varying motivational factors of the drivers. If this is the case, it might be appropriate to adjust the ideal saturation flow rate accordingly during capacity analysis of signalized intersections. In essence, one would be adjusting the saturation flow rate due to varying driver populations, as defined in terms of time of day and day of the week. After an initial investigation at one intersection, it was concluded that there are no significant differences in the operational performance of signalized intersections during different times of the day and days of the week. No differences were found in the mean saturation flow rates for the morning peak period as compared to the afternoon peak period. Likewise, no differences were found in the mean saturation flow rates for different weekdays, Monday through Friday. However, some differences were found in the distribution of headways throughout the week.