Nonlinear Parameters for Granular Base Materials from Plate Tests

Repeated load triaxial tests are widely used to determine nonlinear behavior of unbound granular materials. However, conventional triaxial specimen preparation techniques may not be able to reconstruct the internal structure of a material which has great impact on some of the nonlinear parameters. In addition, it is difficult to reproduce in situ stress conditions in a triaxial cell. In this study, full-scale cyclic and static laboratory plate load tests were performed to investigate the mechanical properties of unbound granular materials. An algorithm was developed to backcalculate nonlinear parameters for prediction of models as a function of bulk stress. Study results demonstrate the pronounced influence of water content on the behavior of unbound granular materials and a generally linear relation between nonlinear parameter K1 and the degree of saturation.