Skripsi
ANALISIS KESTABILAN LERENG MENGGUNAKAN LIMIT EQUILIBRIUM METHODS DENGAN PENDEKATAN KLASIFIKASI MASSA BATUAN PADA PIT. ZA DI PT. BUKIT ASAM TBK, LAHAT, SUMATERA SELATAN
Administratively, the research area is located in the PT. Bukit Asam Tbk precisely at PIT ZA, Sirah Pulau Village, East Merapi District, Lahat Regency, South Sumatra Province. This study aims to analyze geological conditions, engineering geology and the value of safety factors and the probability of avalanches in the research area. In addition, this study aims to recommend an ideal slope design if there are slopes with safety factor values and avalanche probability under stable conditions. The methods used in research are geological mapping, rock mass classification analysis, kinematics analysis and boundary equilibrium analysis. Geological mapping is carried out to collect data in the form of both primary data and secondary data. The results of the primary data will be carried out rock mass classification analysis and kinematics analysis while secondary data will be carried out boundary equilibrium analysis. Rock mass classification analysis is carried out to determine the value of rock mass strength (Rock Mass Rating) and slope stability assessment using Rock Mass Rating Classification. Kinematics analysis was carried out to determine the potential and type of avalanche using Slope Mass Rating (SMR) data. Boundary equilibrium analysis is performed to determine the safety factor index (FK) and avalanche probability (PK). Based on the results of field observations and data analysis, there are three landforms in the study area, namely plateau landforms, concavomorphic landforms, and convexomorphic landforms. The research area is included in the Muara Enim Formation which is composed of claystone, siltstone, and tufaan sandstone lithology with coal inserts. The geological structure that developed in the study area is the descending fault on Fault 1 and Fault 2. Fault 1 according to the classification of Fossen (2010) with the results of Vertical Dip Slip Fault and Rickard (1972) with the results of Right Normal Slip Fault then on fault 2 according to the classification of Fossen (2010) with the results of Vertical Dip Slip Fault and Rickard (1972) with the results of Normal Slip Fault. The results of the boundary equilibrium analysis show that the safety factor and probability of avalanche in four sections, three of which are on the highwall side and one section on the lowwall side. Then after analysis, there are two stable slopes, namely section B-B' with a safety factor value of 1.332 with an avalanche probability value of 5.09% and section C-C' in IB B-C with a safety factor value of 2.030 with an avalanche probability of 1.39%. There are also unstable slopes in three other sections, namely section A-A' with a safety factor value of 0.867 and the probability value of avalanche is 22.59%, then in section C-C' under C with a safety factor value of 1.125 and with the probability value of avalanche is 23.58% and in section D-D' with a safety factor value of 0.922 and with an avalanche probability value of 14.83%. Then in the study area there are two types of rock classifications with Rock Mass Rating weighting at 4 observation locations and 3 locations are obtained that are in class IV or including Good Rock and 1 location that is in class III or including Fair Rock, while in the Slope Mass Rating weighting two classes are obtained, namely class III with normal description and class II with good description. Based on the slope stability analysis, an ideal slope recommendation was obtained in the section which was carried out when the value of the safety factor and probability was below stable according to the company, which was below 1.25. On the intermediate slope add a bench with a width of 20 meters, 30 meters for the width of the ramp, and a height of 8 meters and an angle of 30 ° to strengthen the slope. The results of the re-design itself are that section A-A' has a safety factor value of 1.292 with an avalanche probability of 8.21%, section C-C in Under C has a safety factor value of 1.441 with an avalanche probability of 5.54%, and in section D-D' has a safety factor value of 1.255 with an avalanche probability of 7.52%.
Inventory Code | Barcode | Call Number | Location | Status |
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2407003125 | T145024 | T1450242024 | Central Library (Reference) | Available but not for loan - Not for Loan |