Fault rupture propagation in soil with intercalation using nonlocal model and softening modulus modification

Fault rupture propagation is more complex in the overlying soil with intercalation than in homogeneous soil, and it is challenging to simulate this phenomenon accurately using the finite element method. To address this issue, an improved nonlocal model that incorporates softening modulus modification is proposed. The methodology has the advantage that the solutions are independent of both mesh sizes and characteristic lengths, while maintaining objective softening rates of materials. Using the proposed methodology, a series of numerical simulations are conducted to investigate the effects of different mechanical parameters, such as elastic modulus, friction angle and dilation angle of the soil within the intercalation, as well as the impact of geometries, such as the depth and thickness of the intercalation, on the fault rupture progress. This study not only provides significant insights into the mechanisms of fault rupture propagation, specifically in relation to intercalations, but also shows a great value in promoting the current research on fault rupture.