Influence of vertical load models on flexible pavement response-an investigation

摘要

This paper aims to illustrate the influence of moving loads on pavement analysis, namely their characteristics and time distribution. Firstly, a state-of-the-art load model for pavement analysis is presented. Components of traffic load (contact stresses), their magnitude and time distribution, the tyre-pavement contact area and the characterization of a moving load according to dynamic and static formulations are introduced. Secondly, a study of the influence of load models (uniform vs. non-uniform distribution and non-moving vs. moving load) for pavement analysis by modelling a flexible pavement with the finite element method (FEM) is performed. The structure is modelled with DIANA software (TNO 2005), considering bituminous layers as a viscoelastic material and granular layers and foundation as a linear elastic material. The study reaches the conclusion that pavement response presents different evolutions, during loading time, depending on whether we choose a uniform or non-uniform time distribution load. Considering non-uniform distribution, the maximum value of pavement response can be much higher than those calculated for uniform distribution. It was also confirmed that the moving load character influence decreases not only with pavement depth, but also with distance from the point where the load is applied.