Electronic Theses and Dissertation

Penelitian ini bertujuan untuk menganalisis kestabilan lereng berdasarkan metode klasifikasi massa batuan, metode ini menentukan nilai faktor keamanan, serta mengintegrasikan metode numerik dan empirik. Permasalahan utama dalam penelitian ini meliputi kondisi massa batuan, nilai faktor keamanan lereng di PT Semen Padang, serta pengaruh faktor eksternal terhadap kestabilan lereng. Data yang digunakan terdiri dari data primer berupa struktur batuan (diskontinuitas) dan data sekunder meliputi geometri lereng, Digital Elevation Model (DEM), serta sifat fisik dan mekanik batuan. Metode yang digunakan adalah pendekatan empirik dengan Rock Mass Rating (RMR) dan Slope Mass Rating (SMR), serta pendekatan numerik menggunakan metode kesetimbangan batas (Bishop’s Simplified Method) melalui software Rocscience Slide. Analisis dilakukan pada kondisi kering, basah, jenuh, dan pengaruh peledakan dengan pendekatan pseudostatik. Hasil penelitian menunjukkan nilai RMR sebesar 59 dan SMR sebesar 42 yang mengindikasikan massa batuan berada pada kelas III (fair–normal). Nilai faktor keamanan diperoleh sebesar 1,6 kondisi kering dan 1,4 kondisi basah yang memenuhi standar Kepmen ESDM No. 1827 K/30/MEM/2018, sedangkan nilai 1,1 pada kondisi jenuh berada pada batas minimum. Faktor utama yang mempengaruhi kestabilan lereng adalah tekanan air pori dan getaran peledakan yang meningkatkan gaya penggerak serta menurunkan kekuatan geser massa batuan.

Kata Kunci: Kestabilan lereng, Rock Mass Rating (RMR), Slope Mass Rating (SMR), faktor keamanan, Bishop’s Simplified Method.

This study aims to analyze slope stability based on rock mass classification, determine the factor of safety, and integrate numerical and empirical approaches. The main issues addressed in this study include rock mass conditions, the factor of safety of slopes at PT Semen Padang, and the influence of external factors on slope stability. The data used consist of primary data in the form of rock structure (discontinuities) and secondary data including slope geometry, Digital Elevation Model (DEM), as well as physical and mechanical properties of the rock. The methods applied include empirical approaches using Rock Mass Rating (RMR) and Slope Mass Rating (SMR), as well as a numerical approach using the limit equilibrium method (Bishop’s Simplified Method) through Rocscience Slide software. The analysis was conducted under dry, wet, saturated conditions, and blasting effects using a pseudostatic approach. The results show that the RMR value is 59 and the SMR value is 42, indicating that the rock mass is classified as Class III (fair–normal). The factor of safety values obtained are 1.6 under dry conditions and 1.5 under wet conditions, which meet the standard of the Decree of the Minister of Energy and Mineral Resources No. 1827 K/30/MEM/2018. Meanwhile, a value of 1.1 under saturated conditions is at the minimum threshold. The main factors affecting slope stability are pore water pressure and blasting-induced vibrations, which increase driving forces and reduce the shear strength of the rock mass. Keywords: Slope stability, Rock Mass Rating (RMR), Slope Mass Rating (SMR), factor of safety, Bishop’s Simplified Method.