紧邻大型空区的两阶段矿柱回采爆破参数优化与应用

Optimization and application of blasting parameters for two-stage pillar recovery adjacent to large goafs

采用爆破方法对紧邻大型空区的矿柱回采时,需要综合考虑采空区、运营巷道、硐室、设备以及地面建筑物的安全,同时也需确保爆破效果。为保证紧邻大型空区矿柱回采,以白音诺尔铅锌矿3-6#矿体为例,确定铅锌矿RHT模型参数,优化爆破参数并应用于现场。通过静力学试验确定RHT部分主定参数和从属参数,采用SHPB冲击试验和数值模拟对破碎模型参数进一步拟合,确定铅锌矿RHT模型参数。基于该模型,通过数值模拟确定最佳炸药单耗和排间延时,优化爆破设计。工程实施后,分析现场监测数据,验证了优化后的爆破参数合理性和可靠性;爆破后的大块率由原8%降至4%左右,同时地面和井下被保护的对象均未受影响;爆破对采空区顶板、底板及围岩损伤均较小,采空区处于稳定状态。

When using blasting methods to recover pillars adjacent to large goafs,the safety of goafs,operating roadways,chambers,equipment,and ground buildings needs to be comprehensively considered.At the same time,the blasting effect also needs to be ensured.To ensure the pillar recovery adjacent to large goafs,taking the 3-6#ore body of Baiyinnuoer lead-zinc mine as an example,determine the parameters of the lead-zinc ore RHT model,optimize the blasting parameters and apply them on site.Determine some main fixed parameters and subordinate parameters of RHT through static tests,and further fit the parameters of the fragmentation model by using SHPB impact tests and numerical simulations to determine the parameters of the lead-zinc ore RHT model.Based on the model,the optimal explosive unit consumption and delay between rows are determined through numerical simulation to optimize the blasting design.After the project is implemented,analyzing the on-site monitoring data verifies the rationality and reliability of the optimized blasting parameters.The large-block rate after blasting is reduced from the original 8%to about 4%.At the same time,the protected objects on the ground and underground are not affected.The blasting has little damage to the roof,floor,and surrounding rock of the goaf,and the goaf is in a stable state.