基于矿震活动规律的重复采动高位硬厚岩层冲击机制探讨  

Rock burst mechanism and tremors law of high and thick strata of hard rock during repeated mining

作　　者：王树立[1] 张开智[2] 蒋金泉[3] 朱光丽[1] 俞海玲[1] 

机构地区：[1]山东科技大学矿业与安全工程学院,山东青岛266590 [2]贵州理工学院矿业工程学院,贵州贵阳550003 [3]山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地,山东泰安271002

出　　处：《岩石力学与工程学报》2016年第A02期4172-4179,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51374139;51564004;51574155)~~

摘　　要：针对高位硬厚岩层条件、多煤层开采下煤层强矿震频发问题,以鲍店煤矿十采区200 m超厚高位红层砂岩为工程实例,分析重复采动高位硬厚岩层矿震活动规律及冲击机制。矿震活动规律表明:相比于上煤层而言下煤层开采引起的能量小于104 J的微震事件明显减少,但对开采活动影响较大的能量高于105 J的强矿震事件大大增加;矿震活动总体表现出较弱的规律性,但工作面两侧边界的强矿震事件明显多于中部区域,且工作面采空区侧的强矿震事件远多于实体煤侧。在分析高位硬厚岩层初次破断运动特征的基础上,结合3下煤层开采期间的微矿震活动,提出高位硬厚岩层条件下、重复采动工作面分区域冲击机制:中部由于沉降空间加大,竖向载荷突变造成断裂岩块间剪应力超限,导致原铰接平衡岩块失稳冲击的"剪切滑落型";两侧边界由于岩层移动线外扩,产生高集中应力压实下部垮落岩层导致岩块侧向滑移冲击的"滑移沉降型";2种冲击机制相互交叉、相互促进,"滑移沉降型"冲击在重复采动高位硬厚岩层诱发的动力响应中起主导作用。Aiming at tremors with large energies during repeated mining induced by instability of super-thick strata,using 200 m red beds as an engineering project in Baodian Coal Mine,rock burst and tremors law of high and thick strata of hard rocks were analyzed. The tremors law show that micro-seismic events which energy below 104 J cut down observably compared to upper coal seam,on the contrary,strong rock burst which energy higher than 105 J effecting mining seriously increased observably. In generally the micro-seismic show out no obvious laws,but strong rock burst appearing at boundary sides observably larger than that in middle zone,and show the same laws in gob side compared with the coal side. Based on tremors law and analyzing characters of reds beds during the first fractured,putting forward two rock burst mechanism in different zone. First,in the middle of working face,because of subsidence space enlarged,vertical load will change suddenly caused shearing strength between rock blocks exceeding limits,finally break stable articulated and balance structure,formed type of shear and slip. Second,at boundary sides,the external expansion of strata movement line caused highly-concentrated stress area,and following cause compaction of fractured strata,finally induced rock burst,formed type of slip and backfill. Two mechanisms give a positive function to each other. The type of slip and backfill act predominant in strong rock burst.

关 键 词：采矿工程 重复采动 高位硬厚岩层 剪切滑落 滑移沉降 强矿震 

分 类 号：TD32[矿业工程—矿井建设]