Incorporating the AUS criterion into the limit equilibrium method to study the undrained seismic bearing capacity of strip footings on anisotropic slopes

This study employed the limit equilibrium method (LEM) to assess the undrained seismic bearing capacity of strip footings adjacent to anisotropic slopes. A pseudo-static approach was employed, incorporating horizontal and vertical acceleration coefficients to simulate seismic forces. The anisotropic undrained shear strength (AUS) criterion was adopted for capturing anisotropy in shear strength; however, its application within the LEM introduced some complexity. This complexity arose from the need to solve a system of nonlinear equations. As a result, the Newton method was used to solve the equations efficiently, ensuring accurate results while maintaining computational stability. The results showed a strong correlation between the failure mechanisms predicted by the Finite Element Limit Analysis (FELA) method and the predefined failure mechanisms in the present study. Additionally, the findings emphasise the significant impact of anisotropy ratio on undrained seismic bearing capacity, with reductions of up to 33% observed in some cases.