基于卸支耦合的冲击地压煤层卸压爆破参数优化

Optimization of blasting parameters for rock burst coal seam based on pressure release and support coupling

针对目前参数设计不合理的卸压爆破常常导致支护围岩损伤破坏、降低防冲效率的实际问题,提出了卸压支护耦合思想,并建立其数学模型,推导出最优卸压强度的表达式,分析其主要影响因素,由此,提出了基于卸压支护耦合的煤层爆破参数优化方法。研究结果表明:最优卸压强度与卸压和支护前的初始状态无关,与卸压和支护对冲击危险性的影响权重、卸压和支护与冲击危险性之间的相关参数、卸压和支护之间的转化系数有关;最优爆破方案为卸压效果较好并且对支护损伤较小的爆破方案,依此将古山煤矿爆破卸压方案优化为孔深为12 m,药量为6 kg。现场实践表明该优化方法应用效果良好,既能够确保优化结果的实用性,还可以大幅减少现场工程量,提高优化效率。

Pressure release blasting of unreasonable parameters often damages surrounding rock supports,which reduce the anti-impact capability of supporting rocks.This paper presents a method to optimize parameters of blasting coal seams.The method was based on theory of pressure release and support coupling.A mathematical model was established to derive the optimum intensity of unloading pressure.The factors that influenced the optimum unloading pressure were then analyzed.The study indicated that the optimum intensity of unloading pressure had no correlation with the initial state before unloading and supporting.However,the weighted influence that the pressure release and supporting had on the risk of outburst,the correlation coefficient between pressure release and supporting and risk of outburst,and the conversion coefficient between pressure release and supporting had effects on the optimum intensity of unloading pressure.The optimization method was established a blasting plan for Gushan Coal Mine to achieve the goal of best effect of pressure release and least damage of supporting rock.The results showed that the optimum hole length was 12m and the optimum mass of explosive per hole was 6kg.The field practice implementing these optimum blasting parameters indicates that this optimized blasting plan has an excellent pressure release effect and reduces the damage of supporting,while a high work efficiency is maintained.