The effect of axle load on pavement performance

It is shown that the effect of axle load magnitude on pavement life cannot be accurately assessed without taking into account many factors including pavement strength. The same can be said for load equivalency factors. Empirical methods for determining the effect of axle load are restricted in effectiveness to the pavements producing the data. The source of variability for axle load response originates from material properties and from the structure of the pavement. This paper uses the mechano lattice predictive system to demonstrate theoretically how halving an axle load can produce markedly different pavement behaviour. This is due to the varying build up of residual stresses and strains resulting from the non uniform plastic behaviour of the component pavement layers. It seems therefore that a fresh approach is needed in assessing the effect of axle load on pavement performance (A).