This paper examines how the performance of a pavement under loadcan be predicted using simple, but realistic, models of material behaviour. The key building blocks used are the stress-strain relations for each pavement course. Pavement materials have been divided into two categories: strain-softening and strain-hardening. Readily calibrated algebraic models have been proposed to represent their responses to load. The models have been used to predict the behaviour of an example pavement; they appear to give a reasonable representationof expected pavement behaviour. The models have subsequently been used to explore current predictions of pavement response to load variations, particularly those obtained using the fourth power law. The range of direct usefulness of the law was found to be limited. It has been shown that greater emphasis needs to be placed on (a) the damage caused by the initial passes of overloaded vehicles, and (b) prevention rather than enforcement and penalty levels. Some major misapplications of the fourth power law have also been noted. (A)
Abstract