SLOPE STABILITY ANALYSIS OF THE LOW WALL PIT A LANDSLIDE AT PT XYZ IN EAST KALIMANTAN USING THE LIMIT EQUILIBRIUM METHOD.

• Main Author: Apraditu De Oliveira, Johanes
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/85370
• Institution: Institut Teknologi Bandung

In relation to the landslide incident in the low wall pit A area of PT XYZ, a geotechnical study was conducted with the main objective of determining the strength properties of the weak material that indicated as the primary cause of the landslide. The study also aimed to analyze and provide recommendations for remedial slope steps and geometry, as well as to establish a safe and stable low wall life of mine slope geometry that can be implemented. All geotechnical analyses were conducted using the limit equilibrium method using Rocscience Slide 6.0 software, by defining the location of the slip surface on the low wall slope to calculate the factor of safety (FoS) value. Based on the analysis of exploration drilling results, observations, and the company's historical data, it was found that the slope-forming materials in pit A of PT XYZ include topsoil, overburden (OB) piles, swamp material, sandstone, siltstone, claystone, coal, and other thin material layers with strength conditions ranging from extremely low to very low. Then, from the results of the Back Analysis, the strength properties of the weak layer material were obtained, with cohesion (c) of 90 kPa and internal friction angle (?) of 28.5°. The evaluation results also indicate the need for recommendations on remedial actions and a new slope geometry following the landslide incident. In addition, there is an analysis of the slope geometry recommendation options for the low wall of LOM Pit A, where the second recommendation is the best one to implement, with an FoS = 1.157.