Citation

Yagar S. Aust. Road Res. 1983; 13(1): 3-9.

Affiliation

Univ of Waterloo, Faculty of Engineering, Waterloo, Ont, Can

Copyright

(Copyright © 1983, Australian Road Research Board ARRB)

DOI

unavailable

PMID

unavailable

Abstract

A study of two-lane highway capacity revealed that the U. S. Highway Capacity manual (HCM) estimate of 2000 veh/h in both directions for ideal conditions is inconsistent with sources from around the world. Capacities were found to vary significantly with weather, traffic interference, slow vehicles on grades and directional split. Single lane capacities of up to 2000 veh/h, and two-lane capacities of greater than 3000 veh/h were observed and estimated in Ontario. Results from Japan and Australia indicate that 3600 passenger car equivalents can be served in an hour. Based on these findings, the paper argues that the capacity of two-lane two-way highways may far exceed the HCM's limit of 2000 veh/h if the directional flows are balanced, and that the existing HCM structure for two-lane capacity is not appropriate. An alternative structure for describing ultimate capacities, based on single-lane analysis, is proposed.

Language: en