Soil Nail Design Optimization Through Adaptive Slope Stability Analysis Using Improved Limit Equilibrium Method

ABSTRACT Design optimization for automatically generating optimal design results is a promising technique for enhancing the efficiency of design processes and outcomes. However, its development for soil nail reinforced slopes is limited since the traditional slope stability analysis using the limit equilibrium method (LEM) becomes relatively time‐consuming when the LEM is repetitively employed during design optimization. In this article, an improved LEM for slip surfaces within reinforced slopes is developed, which eliminates the need for dense slice division by only aligning several sampling points using Gaussian quadrature. Unlike conventional design methods, wherein soil nails are represented by predetermined fixed point loads, the proposed improved LEM considers them through equivalent point loads adaptively updated according to the slip surface and nail positions to avoid overly conservative design results. Moreover, an adaptive slope stability analysis (ASSA) is proposed for reinforced slopes, offering an effective evaluation of stability without the need to step through all potential slip surfaces. The effectiveness of the proposed method is validated through several examples, demonstrating substantial computational cost savings of 98.5% compared to directly implementing traditional LEM‐based analysis methods in design optimization, as well as material savings of 30% relative to results from manually designing.