Slope Stability Analysis Against Landslides Using the Bishop Method (Case Study: Katapop II, Salawati District, Sorong Regency)

Retno Puspa Rini; Asrul Saputra; Muhammad Wisnu Winata

Authors

Retno Puspa Rini Civil Engineering, Muhammadiyah University of Sorong, Pendidikan Street, Sorong, Papua Barat Daya
Asrul Saputra Civil Engineering, Muhammadiyah University of Sorong, Pendidikan Street, Sorong, Papua Barat Daya
Muhammad Wisnu Winata Civil Engineering, Muhammadiyah University of Sorong, Pendidikan Street, Sorong, Papua Barat Daya

Keywords:

Slope Stability, Bishop Method, Safety Factor (SF), Soil Characteristics

Abstract

Sorong Regency has hilly and mountainous topography, making it prone to landslides, especially on steep slopes during periods of high rainfall. Landslides in this area can damage infrastructure and threaten human safety. These conditions highlight the importance of slope stability analysis to identify potential landslides and mitigation efforts to minimize disaster impacts. This study aims to analyze slope stability under saturated and unsaturated conditions and to determine the soil characteristics in Katapop II, Sorong Regency. The method used was the Bishop method utilizing GeoStudio software and manual calculations to validate the Safety Factor (SF) values. Based on the calculation results, the slopes in Katapop II were categorized as unstable under saturated conditions, with safety factors (SF) of 0.798 from the software analysis and 0.53 from manual calculations. Under unsaturated conditions, the safety factors (SF) were 2.69 from the software analysis and 2.70 from manual calculations, indicating stable conditions. The soil characteristics were identified as clay according to the AASHTO classification system, inorganic clay according to the USCS classification system, and silt loam according to the USDA classification system.

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