DETERMINATION OF SECURE VIBRATION OF EXPLOSION TO MAINTAIN THE SLOPE STABILITY OF HIGHWALL COAL MINING PT. XYZ

• Main Author: Paranova, Marceleno
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/49029
• Institution: Institut Teknologi Bandung

PT. XYZ is a coal mining company in Indonesia that uses the open pit mining method. Mining activities are carried out by drilling and blasting. The results of the blasting activity are vibration. Vibration can affect slope stability because it is a factor that increases the driving force that can trigger landslides. So, it is necessary to calculate the limit of vibration to maintain slope stability. First, the normality test was carried out on rock data of cohesion, friction angle and unit weight for each lithology using SPSS. Furthermore, rock data were taken for the average value, standard deviation, relative maximum and relative minimum. The mine slopes were then modeled and their stratigraphy using the Rocscience Slide v6.0. The calculation is done by changing the Seismic Load (a) until the slope has minimum Safety Factor based on the Decree of the Minister of Energy and Mineral Resources 1827 of 2018. PPV formula is obtained using Blastware from field measurement data. The results from this study are the maximum PPV value, limit of Scaled Distance and the PPA formula based on Lucca (2003) and field measurements. The maximum PPV and Scaled Distance values are 33.49 mm/s and 8.66 m/kg0,5. The PPA formula based on Lucca (2003) and field measurements are PPA (g) = 0.009 x PPV (mm/s) and PPA'(g) = 0.014 x PPV (mm/s). PT. XYZ was declared safe because the PPV from the blasting was below the maximum PPV and the Scaled Distance was above 8.66 m/kg0,5. The PPA equation based on Lucca (2003) and field measurements has differences because the constant formula Lucca (2003) still depends on the frequency which in this study assumes the frequency is 14 Hz.