Slope Stability Assessment Using a New Finite-Element Analysis with Emphasis on <i>K</i>₀ and <i>&#x3bd;</i> Mutual Influence on the Initial Stress Field

Abstract

A novel finite-element (FE) procedure for analyzing slope stability was recently developed and encoded into a Fortran computer code S4DINA 2.0. This innovative approach involves a gradual increment in the principal stress deviator in a specific way until an unstable condition is reached. In the original version of S4DINA 2.0, the initial stress field was assessed using the gravity loading procedure (GLP), which has various limitations. This paper introduces the fictitious excavation method (FEP) as an alternative procedure for estimating initial stresses. After incorporating the FEP into S4DINA 2.0, a parametric investigation was conducted to explore the effect of the coefficient of soil pressure at rest (K0) and Poisson’s ratio (ν) on the GLP and FEP, which used three selected slope examples. The evolution of the factor of safety (FOS), as determined by the stress deviator increasing model (SDIM), was examined for ν for a variety of soil friction angles (ϕ′). The findings of this paper were documented in detail. The inclusion of K0 as an inherent soil property in the GLP was unfeasible due to the formulation nature of the GLP. In addition, when this method is used, the resulting FOS might significantly deviate from the accurate result in numerous instances. However, in scenarios where K0 exceeds one, the FEP remains the exclusive solution, and when K0 is less than one, selecting the FEP with an appropriate ϕ′ value is the best choice for achieving a rigorous FOS.