基于正交设计模拟实验的预裂爆破参数优化方法研究

Study on Optimization Method of Pre-splitting Blasting Parameters Based on Orthogonal Design Simulation Experiment

由于爆破施工周围待保护环境的复杂性和爆破扰动等有害效应的无法评估性,需对传统的预裂爆破技术进行更精细的改进和优化。采用基于正交设计的相似材料模拟实验方法对预裂爆破中的不耦合系数、同响孔数、孔距孔径比和有无导向孔四个因素进行分析,确定预裂孔成缝效果最优的起爆方式和爆破参数,并进行模拟实验验证。研究表明:装药不耦合系数取2、孔距取8倍炮孔直径、不设置导向孔、采用延期时间为12 ms的逐孔起爆预裂方式,得到有效半孔率为85.4%、预裂缝宽度为25.4 mm、原岩损伤率为13.5%,爆破效果综合评价最佳。

Due to the complexity of the environment to be protected around the blasting construction and the incapability of evaluating harmful effects such as blasting disturbance,traditional pre-splitting blasting technology needs to be improved and optimized more finely.Similar material simulation experiment method based on orthogonal design is used to analyze four factors in pre-splitting blasting,i.e.uncoupling coefficient,number of simultaneous holes,hole distance to hole diameter ratio and whether or not pilot holes exist.The optimum initiation mode and blasting parameters for pre-splitting hole joint formation effect are determined and verified by simulation test.The results show that the effective half-hole rate is 85.4%,the width of pre-crack is 25.4 mm,the damage rate of raw rock is 13.5%,and the blasting effect is evaluated comprehensively.