Citation

Billion CE, Taragin A, Cross EC. Highw. Res. Board bull. 1962; 308: 36-63.

Copyright

(Copyright © 1962, National Research Council (U.S.A.), Highway Research Board)

DOI

unavailable

PMID

unavailable

Abstract

To prevent accidents, guide rails were installed in the center of medians on two parkways. Studies of driver behavior reveal that (1) on the curves with guide rails, drivers reduced their speed, use lanes more effectively and conducted more orderly traffic operations, (2) on tangents, however, no comparable benefits appeared, (3) on one parkway the guide rails were responsible for a 33% drop in accident frequency and for the elimination of fatal head-on and sideswipe accidents in the opposite direction, (4) sideswipe collisions in the same direction increased by 25%, (5) brush collisions with the median guide rail occurred at the rate of one per day for each 2 miles of the rail, (6) the travel section on the second parkway had a much lower accident frequency, and (7) overall the guide rails were judged inadequate to perform all functions to the expected degree even though accidents were reduced.