Citation

Dunlap DF, Fancher PS, Scott RE, MacAdam CC, Segel L. Transp. Res. Rec. 1976; 584: 15-21.

Copyright

(Copyright © 1976, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Requirements for pavement skid-resistance are determined in relation to roadway design elements, tire-tread depth, and rainfall experience. Turnpike accident data are analyzed to show that certain low-curvature curves have higher than average accident involvement histories, and excessive water build-up and, hence, poor pavement drainage is determined to be a responsible factor. Tire traction is shown to be substantially degraded at water depths well below those needed for hydroplanning, and water depth on the road surface is shown to be primarily influenced by road width, superelevation, and rainfall rate and to be essentially independent of grade. We used computer simulation analyses involving parametric variations of vehicles, tires, road surfaces, curvature, superelevation, grade, and maneuvers to define specific limiting velocity boundaries for vehicle-handling performance and then used the accident, traction, drainage, and vehicle performance analyses to develop an equation for required pavement skid number. An example is used to illustrate applications of the equation.