多级爆破卸压技术防治冲击地压机理及其应用

Application and Mechanism of Mine Strata Pressure Pumping Prevention with Multi Stage Blasting Pressure Releasing Technology

以复杂地质条件和开采条件影响的强冲击危险性矿井为研究对象,在顶板、底板和煤层实施多级爆破卸压技术防治冲击地压灾害。采用理论分析、数值模拟和现场试验相结合方法,分析了多级爆破卸压技术的防治冲击地压机理及效果。数值模拟结果表明,实施多级爆破卸压措施后,超前支承压力峰值位置从距煤壁19 m提高到23 m,应力集中系数从1.35降低到1.10;侧向支承压力峰值位置从距巷帮6 m增加到13 m,应力集中系数从1.35降低到1.18。现场试验结果表明,实施多级爆破卸压后钻孔应力和钻屑量明显降低,电磁辐射强度明显增加,支架工作阻力最大下降45%。研究结果表明,多级爆破卸压技术通过切断顶板、底板与煤层之间的应力传递通道,同时使煤层中的高应力区向深部转移,有效降低了煤岩体中的应力和工作面冲击危险性,取得了很好的防治冲击地压效果。

Based on a mine with high strata pressure pumping dangers affected by the complicated geological condition and the mining con-dition as a study object,a multi stage blasting pressure releasing technology conducted from roof,floor and seam was provided to prevent the mine strata pressure bumping disaster.The method combined with a theoretical analysis,numerical simulation and site test were applied to analyze the mine strata pressure bumping prevention mechanism and effect of the multi stage blasting pressure releasing technology.The numerical simulation results showed that before and after the multi stage blasting pressure releasing conducted,a location distance of an ad-vance support pressure peak to the coal wall was increased from 19 m to 23 m and the stress concentration coefficient was reduced from 1. 35 to 1. 10.The location distance of a lateral support pressure peak to the gateway sidewall was increased from 6 m to 13 m and the stress concentration coefficient was reduced from 1.35 to 1.18.The site results showed that after the multi stage blasting pressure releasing con-ducted,the stress and drilling cutting value of the borehole were obviously reduced,electromagnetic radiation intensity was obviously in-creased and the working resistance of the powered support was reduced by 45% in maximum. Therefore,with a cutting off of the stress transmission channels from the roof,floor and seam,the multi stage blasting pressure releasing technology could make a high stress zone in the seam displacing forward to the deep area of the seam,could effectively reduce the stress in the coal and rock masses and the bumping danger of the coal mining face.The good mine strata pressure bumping prevention effect was obtained.