DYNAMIC STABILITY OF SIDEWALL SLOPE DUE TO BLAST VIBRATION AT PT XYZ COAL MINE USING NEWMARK METHOD

• Main Author: Risky Herdinata, Ayes
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/61941
• Institution: Institut Teknologi Bandung

PT XYZ is a mining company that requires blasting for overburden removal. PT XYZ performs Signature Hole Analysis to forecast the vibration characteristics caused by blasting operations. The Newmark method is applied to analyze the slope stability of PT XYZ Sidewall Life of Mine slope using the vibration prediction data. Slope stability analysis is used to determine the maximum amount of explosive charge that can explodes simultaneously while the slope remains stable. The seismic wave profile that produces the critical SRF value is determined to be the maximum value so that the slope remains stable. Meanwhile, the maximum number of explosions is determined from the relationship between the maximum number of explosions and the Scaled Distance. Slope stability analysis with the Newmark method will result in permanent displacement. Permanent displacement is classified according to the impact on the slope. Permanent displacement of up to 5 mm is considered to make the slope unstable, while permanent displacement of up to 50 mm will cause the slope to failure. The calculation of the permanent displacement is carried out using Slide2 software with the SRF value gradually increased at 0.01 intervals until it reaches a critical SRF with variations of the Scaled Distance. Furthermore, the relationship between critical SRF and Scaled Distance is carried out to determine the maximum amount of explosive charge so that the slope remains stable. Maximum number of blasts before the slope undergo a failure is determined by making a relationship between the maximum number of blasts and the Scaled Distance. Based on the slope modeling with the pre-determined scenario, the maximum explosive charge limit per delay time at a certain distance must meet the Scaled Distance requirement of more than 17.50 m/kg0.5. Thus, for the distance of the slope and the blasting location of 148 meters, it is recommended that the maximum amount of explosives that explode simultaneously is 71.4 kg and it is recommended for 125.3 kg amount of explosives at a distance of more than 209 meters. Furthermore, the limit for the maximum amount of blasting experienced by the slope follows the equation: Maximum Number of Blast = 0.0067xSD2.82 with a minimum Scaled Distance that meets the requirements of 5.90 m/kg0.5.