Citation

Heimbach CL, Khasnabis S, Chao GC. Highw. Res. Rec. 1973; 437: 9-19.

Copyright

(Copyright © 1973, National Research Council (U.S.A.), Highway Research Board)

DOI

unavailable

PMID

unavailable

Abstract

Because the roadway designer has no satisfactory technique to evaluate the traffic flow consequences of making selective passing sight distance improvements at spot locations on two-lane, two-way rural highways, a study was undertaken to investigate the relationships between the two independent variables (percentage of total length of a section of highway marked with no-passing barriers and the traffic volume input to the section of highway) and the dependent throughput variables (mean speed, speed variance, volume, travel time, and completed passes). Additional dependent variables investigated, but not verified with field observations, were attempted passes, delay, and speed change cycles. A digital computer traffic model is used to simulate traffic flow over 5- to 6-mile sections of highway at nine field locations in north carolina. Volumes ranges from 175 to 650 vph. The model is calibrated to generate simulation throughput data that statistically match the throughput data observed at the field sites. The calibrated model is then used to analyze simulated systematic changes in no-passing barriers, over volume ranges of 175 to 1,200 vph. The conclusions are that the model is sensitive to these changes, as reflected by the throughput statistics, and that the dependent variables can be correlated with the independent variables in a statistically reliable manner, using multiple linear regression.

Language: en

Keywords

ROADS AND STREETS; TRAFFIC SURVEYS; HIGHWAYS