Abstract
In concrete pavements, subbase and subgrade are required to provide uniform support for concrete slabs. However, permanent deformation at the top surface of subbase due to plastic strains in granular and soil materials causes loss of the support. The aim of this study is to develop a method for predicting the plastic strains in subgrade and subbase. The VESYS model that describes the plastic strain as a function of the number of load repetitions and elastic strain is employed in this study. The model was incorporated into a 3 dimensional finite element program, Pave3D. Validity of the model was verified from a simulation of results of repeated loading test on a test pavement. Also, the effects of the permanent deformation on the stress and deflection of concrete slab were examined.
