Numerical investigation of effect of eccentric decoupled charge structure on blasting-induced rock damage

Abstract

Eccentric decoupling blasting is commonly used in underground excavation. Determination of perimeter hole parameters (such as the blasthole diameter, spacing, and burden) based on an eccentric charge structure is vital for achieving an excellent smooth blasting effect. In this paper, the Riedel-Hiermaier-Thoma (RHT) model was employed to study rock mass damage under smooth blasting. Firstly, the parameters of the RHT model were calibrated by using the existing SHPB experiment, which were then verified by the existing blasting experiment results. Secondly, the influence of different charge structures on the blasting effect was investigated using the RHT model. The simulation results indicated that eccentric charge blasting has an obvious pressure eccentricity effect. Finally, to improve the blasting effect, the smooth blasting parameters were optimized based on an eccentric charge structure. The overbreak and underbreak phenomena were effectively controlled, and a good blasting effect was achieved with the optimized blasting parameters.

Keywords

eccentric charge structure / smooth blasting / rock mass damage / RHT model / parameter optimization

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