Novel approach for the destress blasting in hard rock underground copper mines

Abstract

The present study investigates the possibility of developing a novel method for reducing seismicity and rockbursts in deep underground mines based on modifying drilling and blasting patterns. The main goal was to develop and implement firing patterns for multi-face production blasting, which allow increasing the capability of inducing stress relief in the rock mass, manifested in the seismic event. This method may improve stability control in underground workings, and mitigate risks associated with the dynamic effects of rock mass pressure compared with currently used methods. Thus, the seismic energy may be released immediately after blasting in a controlled way. For this purpose, underground tests using modified blasting patterns and precise electronic detonators were carried out. Vibration data recorded from the multi-face blasting in the considered trial panels were assessed in the scope of amplitude distribution. Results of trials have proven that the method is promising and should be further developed to improve the effectiveness of rockburst prevention in deep hard rock mines.