An Overview of Heavy Trucks/Buses Braking Performance

Richard Ziernicki, Ph.D., P.E. (N.A.F.E. #308S)


The writer discusses the performance of heavy duty vehicles during emergency braking. The paper reviews statistical data related to the truck accidents, and discusses brake performance, tires, and the stopping ability of heavy duty vehicles.

Relationships between drag factor, coefficient of friction, vehicle speed, type of tire, road surface, brake design, and brake temperature are discussed. Some of the test results performed on heavy trucks are presented. The discussion is general in order to make the presentation useful in both to practicing reconstruction specialists, and to attorneys.

Published By


Journal of the National Academy of Forensic Engineers, June, 1991