Response and Permanent Deformation Modelling of an Instrumented Flexible Pavement Structure

Abstract

A flexible test road structure was built and tested in an Accelerated Pavement Test to investigate its performance behaviour for a validation in a mechanistic performance scheme. Halfway through the test, water was introduced to estimate the influence increased moisture content would have on the behaviour of the structure. The raised water level had a significant effect on the behaviour of the structure with decreased resilient modulus and increased rate of accumulation of permanent deformation. Numerical analyses using the multi-layer elastic method (ERAPAVE) as well as finite element analysis (PLAXIS 3D, version 2) have been carried out to simulate the pavement responses, with the material properties based on field and laboratory testing. Thereafter, based on the numerical analyses the observed accumulation of permanent deformation of the unbound layers was modelled using work hardening material models. Generally good agreement was established between the measurements and calculations.