Citation

Kipp OL. Highw. Res. Board bull. 1952; 55: 33-37.

Copyright

(Copyright © 1952, National Research Council (U.S.A.), Highway Research Board)

DOI

unavailable

PMID

unavailable

Abstract

Accidents related to speed, tangent sections and intersections were studied. The four-lane divided highways had the lowest crash rate of all crashes studied in Minnesota and are, therefore, presumed to be the safest. It is concluded that traffic volumes influence accident rates. Curve sections at the ends of long tangents had higher crash rates than were found on curves at the ends of short tangent sections. Curves with restrictive sight distances produced an average crash rate twice the rate for tangent sections with restrictive sight distances. Four-way intersections had consistently higher accident rates than three-way intersections when taken either as a group or by comparable intersectional volumes or by percent of cross traffic. When road sections were segregated by traffic volume groups, a good degree of correlation was apparent between the number of access points per mile and the crash rate. Highway sections having a high frequency of advertising signs had high crash rates. It is concluded that the occurrence of motor vehicle crashes cannot be predicted on the basis of roadway elements and roadside features. However, it is evident that these various elements and features, alone or in combination, make varying degrees of contribution to crash occurrence.