Citation

McCoy PT, Hoppe WJ, Dvorak DV. Transp. Res. Rec. 1985; 1026: 40-43.

Copyright

(Copyright © 1985, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Left-turn lanes are provided on uncontrolled approaches of rural intersections to improve the safety and efficiency of traffic operations on these approaches. Although the safety and operational effects of left-turn lanes are well recognized, there are no generally accepted guidelines that define the circumstances under which the costs of these lanes are justified by the benefits they provide. The objectives of this were (a) to evaluate the benefits and costs of left-turn lanes on the uncontrolled approaches of intersections of rural two-lane highways and (b) to determine the traffic volumes that warrant these lanes in Nebraska. The road-user cost savings associated with the reductions in accidents, stops, delay, and fuel consumption provided by left-turn lanes were evaluated over a range of traffic volumes and compared with the costs of left-turn lanes over the same range. The safety effectiveness of the lanes was based on accident experience on rural two-lane highways in Nebraska. The NETSIM traffic simulation model was used to determine their operational effectiveness. Volumes for which the road-user cost savings exceeded the lane costs were determined to warrant left-turn lanes. The warrants developed in this research are limited to prevailing conditions typical of those on rural two-lane highways in Nebraska. However, the procedure used to develop these warrants is applicable to other locations.

Record URL:
http://onlinepubs.trb.org/Onlinepubs/trr/1985/1026/1026-005.pdf

Language: en

Keywords

ROADS AND STREETS - Intersections; STREET TRAFFIC CONTROL; TRANSPORTATION - Accident Prevention