ANALYSIS OF VIBRATION EFFECT ON SURFACE BLASTING TOWARDS THE STABILITY OF TUNNEL # 4 THE INDONESIA-CHINA HIGH SPEED RAILWAY PROJECT, PURWAKARTA

• Main Author: Maulana, Yuga
• Format: Theses
• Language: Indonesia
• Subjects: Pertambangan dan operasi berkaitan
• Online Access: https://digilib.itb.ac.id/gdl/view/51995
• Institution: Institut Teknologi Bandung

The blasting activity of a quarry mine that is above the surface of tunnel # 4 of the IndonesiaChina High Speed Railway has the potential to disrupt the stability of the tunnel if the tunnel is active. Therefore a prediction is needed to determine the maximum limit of explosives that can be used in the quarry mine. Vibration prediction is carried out by two different methods, there are the scale distance method and the artificial neural network that using previously measured blasting vibration measurement data. The results obtained are that the prediction using artificial neural network has a higher level of confidence and the value of the standard error of estimate is the smallest compared to the equations using the scale distance method with a value of 93% and 0.87. Therefore, the prediction of explosives was continued using an artificial neural network and obtained a value of 43 kg for a peak particle velocity of 20 mm / s at a distance of 21 m. These results are used as data for surface blasting simulations to see the stability of the roof and tunnel walls with a 3-dimensional numerical model using the finite element method. Simulation modeling is done by simulating blasting, namely loading the blast load 3 times / event. The peak particle velocity results on the model show a figure of 20.34 mm / s on the roof of the tunnel, and also show that the stability of tunnel # 4 after 3 blasting times is still in the safe category. This is indicated by the very small decrease in the safety factor of the roof, right and left walls of the tunnel with the final values above 1 respectively, which are 6.09, 4.48, and 3.69. Likewise, the results of the strain that occurred on the roof and tunnel walls after 3 blasting times were 0.01 and 0.03%, these values were still below the maximum allowable stretching value.