LANDSLIDE HAZARD INVESTIGATION AND SLOPE STABILITY ASSESSMENT OF INDRAPURI HOUSING PEKANBARU, INDONESIA

Abstract

Housing development in Indrapuri, Pekanbaru, located in a hilly area with steep terrain, presents potential landslide hazards due to soil cutting and filling activities. This research is essential to determine whether the housing development at this location is stable from landslide hazards, necessitating a scientific slope stability analysis. The study aims to evaluate the safety factor of cut slopes, analyse landslide hazards based on soil characteristics, and assess the impact of slope height on landslide potential. The research methodology involves slope investigations, soil characteristic testing in field and laboratory settings, and slope stability evaluation using the Fellenius Method. Field investigation results indicate that slope heights vary from 2 m to 5 m, with a slope angle (α) of 68°. The soil shear strength parameter (ø) varies between 21.25° and 64.85°, while cohesion (c) ranges from 43.97 kN/m² to 84.56 kN/m². These parameters can affect slope stability. At the Indrapuri site, variations in soil shear strength and cohesion are likely influenced by geological and environmental factors. Slope stability analysis reveals that the current slope conditions are stable from landslide hazards, with safety factor values ranging from 2.42 to 5.20. These values exceed the minimum threshold for slope stability (SF ≥ 1.25), indicating stable conditions. However, under extreme rainfall conditions or additional loading, the safety factor may decrease significantly and approach the critical limit (SF≤ 1.07), potentially leading to slope failure.