SLOPE STABILITY ANALYSIS AT PT XYZ COAL MINING DISPOSAL IN SOUTH KALIMANTAN PROVINCE

• Main Author: Rahman Amrullah, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/57476
• Institution: Institut Teknologi Bandung

PT XYZ is a mining company that carries out coal mining activities in South Kalimantan Province now days it’s disposal is facing slope failure which occurred at RL+90 to RL+30 on the northern side of disposal. In order to find out the cause of the failure, a back analysis was carried out by conducting slope modeling using field data and Rockscience slide v6.0 software. The results of the back analysis showed that the factors causing the slope failure of PT XYZ's disposal slope were the saturated disposed material condition and the disposed material strength of 85% with a cohesion value of 60.80 kPa. As well as, the presence of weak material on the disposal foundation which triggers the occurrence of non-circular slope failure in the disposal. By using the results of the back analysis, the slope stability analysis applied to the planned disposal show that the design of the disposal slope in unstable conditions with a circular and non-circular failure safety factor value of 0.942 and 0.933, respectively, with probability of failure 67,6% and 73,2%, respectively. In order to meet the slope safety criteria in the Keputusan Menteri ESDM No. 1827/K/MEM/2018, some recommendation of remedial action for the planned disposal are made. By applying the recommendations given, generated value the static safety factor for the potential circular failure and non-circular failure will be 1,299 and 1,325 with a probability of failure 0,4% and 0%. And the dynamic safety factor for the potential circular failure and non-circular failure will be 1,202 and 1,231 with a probability of failure 4,2% and 0,4%.