Discrete-element modelling of underground tunnel response to reverse fault rupture in sand

Abstract

Using discrete element numerical method (DEM), the present paper aims at simulating the interaction between underground tunnel in sand deposit while a reverse fault rupture propagates from the bedrock to the ground surface. Propagation pattern of fault ruptures and the deformation profiles of the soil at the ground surface are discussed in detail considering the effect of tunnel location and tunnel rigidity. Numerical simulations are verified against a set of centrifuge laboratory experiments. The DEM simulations are compared with a set of finite elements (FEM) numerical models and the efficiency of each method in simulation of fault rupture-tunnel interaction is discussed for the first time. Both DE and continuum numerical models are effective complementary tools capable of providing valuable insight into tunnel-fault rupture interaction mechanisms, however, the findings indicate a better correlation between DEM simulations and the experimental results.