ANALYSIS OF THE EFFECT OF BLASTING VIBRATION ON SIDEWALL SLOPE STABILITY WITH PSEUDO-STATIC APPROACH AND MAXIMUM AMOUNT OF EXPLOSIVES CHARGE RECOMMENDATIONS

• Main Author: Dirgantara Hadi, Xavier
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/61948
• Institution: Institut Teknologi Bandung

Ground vibration due to blasting is one of the factors that cause slope stability to decrease. Slope stability analysis was carried out on sidewall slopes to obtain static FoS value, dynamic (pseudostatic) FoS, critical peak particle acceleration (PPA), static probability of failure (PoF) value, and the maximum amount of explosive charge. First, an analysis is conducted on the ground vibration monitoring data to obtain an equation of the relationship between the PPA and scaled distance (SD). In slope stability analysis, descriptive statistical analysis is performed to obtain the input parameters in Slide v6.0 software, where the required parameters from these analysis are mean, standard deviation, minimum, maximum, and distribution type on the required rock characteristics data, namely cohesion, internal friction angle, and unit weight in mudstone, sandstone, and carbonaceous mudstone. To obtain the static PoF value, probability of failure analysis is conducted using Monte-Carlo simulation. Based on the slope stability analysis, it was discovered that the slope condition was not safe because the static PoF value is over 5%, so it was necessary to make changes to the slope geometry. After the slope geometry changes, the test is carried out by changing the seismic load (a) until the slope has a minimum dynamic FoS value based on the Minister of Energy and Mineral Resources Decree 1827K/30/MEM/2018. The results of the slope stability analysis show that the slope condition is safe, with a static FoS value of 1.408, static PoF 4,7%, and dynamic FoS 1.1 with the critical a of 0.1 g. The critical PPA value obtained is 0.2 g. Blasting is not recommended at a distance below 150 meters from the sidewall slope. Above that, the maximum amount of explosive charge is 71.4 kg at a distance of 150 meters, 126.87 kg at a distance of 200 meters, 198.23 kg at a distance of 250 meters, and 214.2 kg at a distance of 260 meters and so on.