Optimization of blasting for high-efficiency and low-damage drivage of large-section production drifts in block caving

Abstract

Abstract Excavating large-section production drifts in block caving mines faces critical challenges regarding surrounding rock stability and drivage efficiency. To address these issues, this study optimizes full-face blasting parameters through coupled numerical simulations and industrial verification. The investigation focuses on the cavity formation mechanism of large-diameter burn cuts and the damage evolution characteristics during full-face blasting. Simulation results indicate that a four-uncharged-hole cut design creates a symmetrical and regular free surface, effectively balancing blasting performance and economic efficiency. Furthermore, an optimal auxiliary hole spacing range is established to minimize damage to the surrounding rock. Field implementation at the -450 m level of the JAMA Mine demonstrated that the optimized scheme resulted in a well-formed roadway profile with an average half-cast factor exceeding 90%. The average advance per round stabilized at 3.31 m, representing a 6.8% improvement over the original scheme. This research establishes a high-efficiency, low-damage blasting technique for deep large-section roadway drivage, providing a valuable reference for similar engineering projects.