Influence of Depth and Position of Vibration-Isolating Slot on Damping Effect of Blasting Vibration

Abstract

The blasting vibration has an impact on the rock and soil around the blasting hole and the nearby structures. The vibration-isolating slot is one of the methods to reduce the damage of blasting vibration. In this paper, the influences of the depth and position of the vibration isolation slot on the PPV (peak particle velocity) attenuation characteristics of the ground vibration and blasting vibration damping effect of the vibration isolation slot at different measuring points are studied systematically by LS-DYNA numerical models. The results show that the damping effect of the vibration isolation slot is realized by reflecting the blasting vibration wave and increasing the propagation paths of the blasting vibration wave. When the measuring points are 5 m∼45 m far away from the vibration-isolating slot, the average vibration damping effect of the vibration-isolating slot is more than 30% and the deeper the depth of the vibration isolation slot, the better the vibration damping effect when the measuring points are 5 m∼15 m far away from the vibration isolation slot. However, when the measuring points are 15 m∼45 m far away from the vibration isolation slot, the vibration damping effect is best when the depth of the vibration isolation slot is 15 m. The vibration damping effect of blasting vibration at the same measuring point is different due to different positions of vibration isolation slot. For the measuring points M3 and M5, with the increasing of the distance between the vibration-isolating slot and the explosion source, the vibration damping effect of the vibration-isolating slot shows an increasing-decreasing-increasing trend; however, it shows a decreasing-increasing-decreasing trend for the measuring point M4.