The influence of granular base characteristics on upper bound shakedown of pavement structures

In this paper a numerical methodology for determining the upper bound shakedown load is presented. This methodology is used to study the shakedown load of typical pavement sections with granular bases. Results obtained from a matrix of numerical runs are used to establish empirical correlations between shakedown limit (i.e. applied pressure on the surface of the pavement at shakedown) and other system properties. Correlations are also established for the critical response parameters of the pavement components at shakedown. These correlations are used in a sensitivity analysis to determine the relative influence of the base characteristics on shakedown limit. The effect of loss of base modulus and shear strength as a result of increased pore water pressure under saturated conditions of the base is also investigated.