Evaluating the performance of soil nailing in slope stability under complex conditions

Abstract

Soil nailing has become a widely adopted slope stabilisation technique for enhancing the structural integrity of soil and rock masses, especially in earthquake and landslide-prone areas. It has effectively stabilised both natural and man-made slopes by preventing erosion, settlement, and other forms of failure, as well as reinforcing existing foundations. In this paper, to investigate the effect of soil nailing on slope stability, a two-dimensional finite element method (2D-FEM) has been used to simulate four different slope conditions: Case-I (no surcharge, no nails), Case-II (surcharge without nails), Case-III (surcharge with nails), and Case-IV (nails without surcharge). This study has introduced a numerical framework that has examined plastic equivalent deviatoric strain, plastic strains along the x- and z-planes, and plastic shear strain to comprehensively assess displacement behaviour under varying conditions. The results have shown significant reductions in displacements along the xdirection (dx), z-direction (dz), and resultant displacement magnitude (|d|), particularly in Cases III and IV. Furthermore, the analysis has taken into account several environmental scenarios: (A) without groundwater table (GWT) and seismic loading, (B) with GWT but no seismic loading, (C) without GWT but with seismic loading, and (D) with both GWT and seismic loading. Across all scenarios, the use of soil nails has significantly increased the factor of safety (FOS), whereas increasing the slope angle from 30° to 90° relative to the horizontal plane has resulted in a decrease in FOS, indicating a critical balance between slope inclination and stability. Overall, this study has demonstrated the effectiveness of soil nailing in enhancing slope resilience and has provided comprehensive insights into its performance under diverse environmental and loading conditions.