Experimental Validation of a Numerical Model for the Dip-Slip Normal Fault Rupture Propagation through Sand Deposits

Abstract

An improved numerical model for the accurate prediction of the fault rupture mechanism through the overlying soil gives confidence to the engineers in sitting the structures near or above faults. In this work, a sophisticated numerical model incorporating a hardening-softening constitutive model with shear band effect is calibrated from the direct shear model test results and validated for the prediction of the behavior of medium dense Fontainebleau sand bed due to quasi-static normal movement of the bed rock of fault with dip angle equals to 60°. The numerical results show satisfactory agreement with the experimental data from centrifuge (115g) and 1g model tests in terms of normalized vertical displacements profile of the ground surface, minimum relative vertical base displacement for the rupture to reach the ground, the average dip angle propagated into the soil as well as the horizontal extent of the deformed surface ground. The effect of the very low stress fields in the 1g tests (scale effect) is discussed.