Optimalisasi Geometri Lereng Tambang Nikel Menggunakan Metode Probabilistik Pada Hill Pit 05, PT Vale Indonesia Tbk, Sorowako, Kabupaten Luwu Timur, Provinsi Sulawesi Selatan

Abstract

PT Vale Indonesia Tbk evaluates the initial slope design in an effort to ensure the slope is stable and has no potential for landslides by optimizing the single and overall slope geometry. The method used includes a good test method to characterize data, the "Bishop Simplified" border equilibrium method for determining the safety factor value (SoF), How to Cite: Azizi, M. A., Hakim, R. N., Nugraha, A .D. 2019. Optimalisasi Geometri Lereng Tambang Nikel Menggunakan Metode Probabilistik Pada Hill Pit 05, PT Vale Indonesia Tbk, Sorowako, Kabupaten Luwu Timur, Provinsi Sulawesi Selatan. Jurnal Geomine, 7(2): 92-100. and the Probabilistic method using the Monte Carlo Sampling method to multiply data and determine the probability of sliding (PoS). Good test results were obtained for limonite rocks, the best type of distribution for content weights is lognormal, cohesion is gamma and the internal friction angle is normal. Whereas in saprolite rocks, the best type of distribution for fill weight is normal, cohesion is gamma and the inner friction angle is normal. The results of the optimization of a single slope geometry with a slope height of 10 meters with a slope angle of 60 °, resulting in a FK value of 1.52 and a PK of 23.9%. The evaluation results of the initial
design of the overall slope of section I - I 'obtained a height of 58.6 meters slope with a slope angle of 22 ° resulting in a FK value of 1.09 and PK of 52.7%. After redesigning it was found that the slope height was 57.7 meters with a slope angle of 190 resulting in a FK value of 1.36 and a PK of 14.5%.