Numerical investigation of the impact of rock mass properties on propagation of ground vibration

Abstract

Ground vibrations induced by the blasting of explosives can cause damage to the slope stability of mines. The important indicators of rock mass such as the geological discontinuities, physical and mechanical properties of rock can affect the creation and prediction of blast damage. This paper aims to assess the simultaneous effects of the above properties. For that purpose, peak particle velocity as the indicator of damage at two rock slopes was examined through a three-dimensional distinct element code (3DEC). The developed model simulated the dynamic pressure of detonation and provided useful results for analysis. The qualitative analysis demonstrated how significant it is to incorporate the rock mass properties in the model. Moreover, a statistical analysis was performed to quantify the effects of these properties. Therefore, the distance from blast, dip/direction of discontinuities, blast damage factor (Hoek–Brown failure criterion) and Geological Strength Index have the most influences on the slope damage, respectively. The moment failure analysis of 3DEC explained the Shear–Tension and Shear–Shear failures associated with the rock mass damage caused by blasting. The dip/direction of discontinuities plays a major role in the control or propagation of dynamic pressure and should be considered in blast damage control. If necessary, artificial discontinuities such as pre-splitting should be employed for better control and use of the favorable effects of geological discontinuities.