The determination of the relationship between friction and traffic accidents

Abstract

The notion that friction coefficients are a significant contributory factor in traffic crashes has been firmly entrenched in the literature since the work of Giles (1956). As a result, many highway authorities have set minimum friction requirements for road surfaces, below which the probability of a crash is considered unacceptably high. The safety benefit ascribed to friction coefficients arise from its ability to facilitate various vehicle manoeuvres, most notably braking and cornering.

In the United Kingdom minimum friction coefficient requirements for trunk roads were first prescribed in 1988 in the Design Manual for Roads and Bridges. In 2004 the minimum friction coefficient requirements as prescribed by this policy were either maintained, or increased (Viner et al., 2004). This action is alluring given that since the original 1988 policy, the vehicle fleet has improved significantly not just in terms of vehicle safety, but also in its ability to generate increased levels o