Numerical Analysis of Slope Failure Remediation Using Geosynthetic Reinforcement

Abstract

Slope failures often occur due to inadequate shear resistance within soil layers, posing serious risks to infrastructure and transportation corridors. Geosynthetic reinforcement has been widely adopted as an effective and economical solution for improving slope stability; however, its performance needs to be quantitatively verified through numerical modeling. This study aims to evaluate the effectiveness of geosynthetic reinforcement in slope failure remediation using a numerical approach. Field investigation data, including Standard Penetration Test (SPT) and laboratory parameters, were combined with empirical correlations to define the soil model. Numerical analysis was conducted using the GEO5 Slope Stability software to simulate both the existing and reinforced slope conditions. The back analysis of the failed slope yielded a factor of safety (FoS) of 0.93, validating the observed field failure. Reinforcement was designed with woven PET geotextile based on the graphical method by Jewell (1990), applying reduction factors in accordance with FHWA and SNI 8460:2017. The reinforced model achieved a FoS of 8.96 under static loading and 3.62 under pseudostatic loading (kh = 0.18 g), demonstrating significant improvement in slope stability. The results confirm that numerical modeling effectively captures the behavior of reinforced slopes and provides a reliable design framework for remediation of slope failures. The findings have practical implications for geotechnical engineers in optimizing geosynthetic applications for both static and seismic conditions.