摘要
为研究上分层遗留煤柱对下分层工作面回采的影响,以山东金桥煤矿1304工作面为工程背景,采用FLAC3D模拟软件,研究了煤柱塑性区和支承压力分布及下分层工作面分步回采期间的支承压力演化规律。研究表明:当下分层工作面未采时,两采空区侧向支承压力叠加,在煤柱体边缘形成2个应力集中区,应力集中系数分别为2.2和2.8。煤柱体发生全部塑性破坏形成屈服煤柱,能够支撑覆岩施加的载荷,不易诱发失稳动力灾害。当下分层工作面开采时,煤柱体由两面采空变为三面采空状态,应力集中系数由3.8增至4.5,在强支承压力作用下可能诱发煤柱“蠕-突变”失稳型冲击地压。因此,回采期间应加强煤柱冲击危险监测,并采取大直径钻孔预卸压解危措施。
In order to study the influence of the upper stratified residual coal pillars on the mining of the lower stratified working face,the 1304 working face of Shandong Jinqiao Coal Mine was taken as the engineering background.FLAC3D simulation software was used to study the plastic zone and bearing pressure distribution of coal pillars and the evolution of bearing pressure during the step-by-step mining of the lower layer working face.The research shows that when the stratified working face is not mined,the lateral bearing pressures of the two goafs are superimposed,and two stress concentration zones are formed at the edge of the coal pillar,and the stress concentration factors are 2.2 and 2.8 respectively.The coal column undergoes all plastic failure to form a yielding coal pillar,which can support the load applied by the overburden and is not easy to induce a destabilizing dynamic disaster.When the lower stratified working face is mined,the coal pillars are changed from two-sided mining to three-sided emptying.The stress concentration factor is increased from 3.8 to 4.5,which may induce the“creep-mutation”instability type rock burst of coal pillar under the action of strong supporting pressure.Therefore,during the mining period,the coal pillar impact hazard monitoring should be strengthened,and the large-diameter borehole pre-relieving pressure measures should be taken.
作者
马宁
张臣
贾江锋
丁楠
李小裕
束佳明
MA Ning;ZHANG Chen;JIA Jiangfeng;DING Nan;LI Xiaoyu;SU Jiaming(State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Tai’an 271000,China;College of Mining and Safety Engineering,Shandong University of Science and Technology,Qingdao 266590,China)
出处
《煤矿安全》
CAS
北大核心
2019年第12期192-196,共5页
Safety in Coal Mines
基金
国家自然科学基金资助项目（51704185,51704182）
山东省自然科学基金资助项目（ZR2017BEE045）
关键词
遗留煤柱
支承压力
FLAC3D软件
数值模拟
塑性区
remaining coal pillar
bearing pressure
FLAC3D software
numerical simulation
plastic zone
