Numerical analysis of surface foundation subjected to strike–slip faulting: model boundaries, pre-softening volumetric response, parametric study

The paper investigates strike-slip fault rupture propagation through dense sand and its interaction with surface foundations, employing 3D finite element (FE) modelling. Two soil constitutive models (implemented in Abaqus user subroutines) are employed for this purpose: (i) a recently developed simple yet efficient model Mohr–Coulomb yield criterion, which incorporates post-yield isotropic frictional hardening softening (MC–HS model); (ii) the basic version of more sophisticated hypoplastic sand. Both calibrated on basis monotonic triaxial compression tests (and an additional oedometer test model), conducted as part study. numerical predictions comparatively assessed against centrifuge results. In accord tests, free-field analyses MC-HS reveal complex pattern at ground surface, consisting Riedel (R) shears. These surficial manifestation structures helicoidal geometry, attributed to spatial variation shear stresses within overburden due imposed bedrock offset. development R shears is primarily controlled by pre-softening volumetric response dilation. latter underestimated model, thus predicting formation single straight band instead A parametric study validated exploring rupture–soil–foundation interaction. Foundation shown be sensitive (R vs. trace), but mechanism (rotational translational) foundation distress not affected same extent. two-step design strategy outlined, requiring analysis capture pattern, followed minimum four analyses, varying fault-normal fault-parallel location.