摘要
针对山西某矿工作面上方存在厚硬岩层,在工作面回采后不易垮落极易引发冲击地压事故的问题。采用理论分析及数值模拟试验的方法,分析了工作面回采过程中采场应力分布、围岩变形特征及塑性区发育规律。提出采用深孔预裂爆破的方法对采场上覆坚硬岩层进行弱化处理。采用数值模拟试验的方法,对比分析了单孔及扇形孔的弱化效果,最终确定在工作面布置扇形孔进行断顶卸压,并在3202工作面进行现场试验。现场微震监测数据显示:对顶板坚硬岩层进行扇形孔爆破断顶后,微震事件数量明显减少,微震事件能量也明显降低,卸压效果显著。
Regarding the issue that a thick and hard rock stratum exists above the working face of a mine in Shanxi,which is unlikely to collapse after the working face is mined and is highly prone to triggering rock burst accidents.In this paper,theoretical analysis and numerical simulation tests are employed to analyze the stress distribution in the stope,the deformation characteristics of surrounding rocks,and the development law of the plastic zone during the working face mining process.A method of deep-hole pre-splitting blasting is proposed to weaken the hard overlying rock strata of the stope.Through numerical simulation tests,the weakening effects of single holes and fan-shaped holes are compared and analyzed.Finally,it is determined to arrange fan-shaped holes in the working face for roof cutting and pressure relief,and field tests are conducted in the 3202 working face.The field micro-seismic monitoring data shows that after the fan-shaped hole blasting for roof cutting of the hard roof strata,the number of micro-seismic events is significantly reduced,and the energy of micro-seismic events is also significantly decreased,indicating a remarkable pressure relief effect.
作者
宁杰松
NING Jiesong(Jiaojiazhai Coal Mine,Xuan'gang Coal and Electricity Co.,Ltd.,Jinneng Holding Mining Industry Group,Xinzhou 034115,China)
出处
《煤》
2026年第3期66-70,共5页
Coal
关键词
坚硬顶板
爆破断顶
扇形孔
断顶卸压
hard roof
blasting cutting roof
scallop hole
roof cutting and pressure releasing
