APLICATION OF PROBABILISTIC APPROACH IN ROCK SLOPE STABILITY ANALYSIS FOR NORTH WALL INSTABILITY AREA (FAILURE #79) AT PT NEWMONT NUSA TENGGARA

• Main Author: SANTOSO (NIM : 22110001), EKO
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/21909
• Institution: Institut Teknologi Bandung

In rock slope stability analysis is compromised by a variety of problems. One of arises from uncertainty and variability in rock and rock mass properties. Hence, assessment of performance of slopes cannot be accurately predicted. Traditional slope stability analysis have been made on the basis of the allowable Faktor of Safety (FOS) and used single value estimates for each parameter in the slope stability equations. Probabilistic method offers a more systematic way to treat uncertainties at parameters used for slope stability analysis and give an alternative to FOS approach, namely Probability of Failure (POF). <br /> <br /> <br /> <br /> <br /> The main objective of this research is to applay probabilistic approach in rock slope stability analysis. The research began with process of characterization of rock and rock mass properties that used as input in rock stability analysis, then continuing to calculate the probabilty of failure. Limite Equilibrium Method (LEM) and Finite Element Method (FEM) are used to calculate the probability of failure. It does so using two probabilistic approaches: the monte carlo simulation method and Point Estimate Method (PEM). The case study of this research is in north instability area of pit Batu Hijau PT Newmont Nusa Tenggara. <br /> <br /> <br /> <br /> <br /> Results of probabilistic analysis for the current study give the average value of POF more than 50 %, this indicate that slope are not stable and big possibility to failure. based on the acceptable criteria POF for inter-ramp that slope will stable at POF &#8804; 25 % (SRK, 2010). The research recommended to reduce the actual slope geometry from ( H = 210 m and IRA = 45°) become H = 135 m with slope angle (IRA = 41°), this new slope geometry have POF = 24.62 %.