Non Linear Finite Element Analysis of Reinforced and Unreinforeced Pavements

In this research a comprehensive finite element program was developed in order to carry out an elasto perfectly plastic analysis of geogrid reinforcement of a model pavement. Qualitative agreement is seen between the numerical results and experiment. The results indicate the influence of geogrid in reduction of vertical deformation of pavements. It is also seen that for strong subgrade, the optimum position of geogrid in base layer is at the level of maximum lateral displacement. This indicates that the main mechanism of geogrid is to restrain soils from lateral displacement through interlocking with the particles. Furthermore, the results show that if deformation of subgrade is concerned (e.g. weak subgrade) the optimum position of geogrid is at the base-subgrade interface due to substantial reduction of horizontal stress transferred subgrade.