Slope Stability Analysis Using Plaxis & Slope/W (Case Study: Bagbagan-Jampangkulon Road Section STA 8+400, STA 8+200, and STA 13+000)

Abstract

The Bagbagan - Jampang Kulon Road Section in Sukabumi Regency faces soil stability challenges primarily driven by natural factors. A safety factor exceeding 1.5 is considered secure. Analyses were performed using PLAXIS (Finite Element Method) and SLOPE/W (Limit Equilibrium Method). For the road section at various points (STA 8+200, STA 8+400, and STA 13+000) under Class I pavement loads (12.5 kN/m), PLAXIS yielded safety factors of SF=1.387, SF=1.315, and SF=1.265, while Class II loads (10 kN/m) produced SF=1.388, SF=1.318, and SF=1.267. SLOPE/W analysis under Class I loads yielded SF=1.295, SF=1.226, and SF=1.015, with Class II loads producing SF=1.297, SF=1.229, and SF=1.017. Minor discrepancies of approximately 8-9% at STA 8+200 and STA 8+400 and 1.2% at STA 13+000 were observed between the two programs. Despite these variances, PLAXIS and SLOPE/W provide reasonably close safety factor results. These differences may be attributed to each program’s distinct assumptions and calculation methods. Overall, both methods underscore the need for reinforcement to enhance slope stability in this critical road section.