Analisis stabilitas lereng dengan perkuatan gravity wall dan cantilever wall di Desa Sukaraharja, Cianjur, Jawa Barat

Sukaraharja Village in Cianjur, West Java, possesses a sloping topography prone to failure, primarily triggered by high rainfall, which has demonstrably caused landslides that interrupt vital access and compromise public safety. Based on the preliminary analysis indicating that the existing slope's Safety Factor (SF) is below the required safety limit (SF < 1.5), this research aims to analyze the slope stability and design an effective reinforcement solution. The main focus of the study is to compare the structural effectiveness of the gravity wall and the cantilever wall. The research method employed a comprehensive slope stability analysis by integrating actual soil parameter data obtained from field sampling and laboratory tests, including soil classification (ML and OH) and soil shear strength parameters. Stability analysis was conducted using two approaches: the Fellenius method and the Finite Element Method (FEM) with the aid of PLAXIS 2D V21 software. Reinforcement evaluation was performed in detail, covering external, internal, and global stability checks, tested under two loading conditions: without seismic load and considering pseudo-static seismic load. The existing slope analysis results were categorized as unsafe, with SF values of 1.111 (Fellenius) and 1.057 (PLAXIS 2D V21). Following the implementation of reinforcement, stability significantly increased beyond the required minimum safety limit. For the non-seismic loading condition, the gravity wall reinforcement successfully raised the SF to 2.288, while the cantilever wall provided an SF of 2.157. Although under seismic loading conditions both structures showed SF values close to the critical limit (SF gravity wall = 1.295 and SF cantilever wall = 1.310), both the gravity wall and cantilever wall are recommended as effective and efficient reinforcement options for landslide mitigation in Sukaraharja Village because both have satisfied the stability requirements in accordance with SNI 8460:2017.