LONG-TERM STABILITY ANALYSIS OF PT XYZ COAL MINE HIGHWALL SLOPE

• Main Author: Holy Simanjuntak, Abraham
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/76599
• Institution: Institut Teknologi Bandung

PT XYZ is one of the coal mining companies operating in South Kalimantan Province. PT XYZ intends to evaluate the long-term stability of highwall slopes in the Life of Mine (LOM) design. This study aims to determine the stability of the LOM design slope by considering long-term strength parameters, and provide recommendations for slope repair if there are unsafe slopes from the analysis results. The classification of whether the slope is safe or not is based on the Minister of Energy and Mineral Resources Decree No. 1827K/30/MEM/2018 by calculating the Safety Factor (SF) in static and dynamic conditions and calculating the Probability of Failure (PoF). Preliminary analysis was conducted on the highwall slope design without taking into account the long-term strength. Based on the analysis results, the highwall slope is in a stable condition with static FK ? 1.3, dynamic FK ? 1.5 and PK ? 5%. The analysis is then continued by considering the long-term strength of the rock. The result of the most suitable distribution then became the input parameter to the Slide 6.0 software used to analyze the probability of landslide. The results of the analysis using the longterm strength parameter showed that the slope was in an unsafe condition. Therefore, recommendations are needed to repair the slope so that it can be categorized as safe. The recommended improvements are slope grading and provision of backfill material as inpit dumps. Based on these recommendations, the slope is categorized as safe with static SF values ranging from 1.3-1.389, dynamic SF values ranging from 1.188-1.1.237, and PoF values ranging from 0%- 1.9%.