摘要
为了对坚硬厚顶板这种特定地质条件下的冲击地压防治技术进一步细化研究,分析了宽沟煤矿I010203工作面开采过程中上覆坚硬厚顶板冲击地压过程,提出了相应的防冲技术措施,并基于工作面卸压防冲前后微震事件时空变化规律对防治技术进行了效果检验,研究结果表明:B;煤层开采后上覆坚硬厚顶板易在I010203工作面采空区及相邻I010201采空区之间的煤柱区域产生悬顶,不但会造成煤体静载应力集中,而且造成能量积聚,从而产生大量动载,悬顶长度过长时会发生垮落、破断等强动载扰动,当动载荷和静载荷叠加超过临界值时便会造成冲击显现,煤柱集中静载和坚硬顶板破断动载是冲击地压主控因素。根据上述冲击地压分析结果,设计了顶板断顶预裂和煤体超前爆破两种卸压技术措施,并选取卸压前后稳定生产期间的微震事件进行卸压效果对比分析,卸压后微震日总能量和日总频次明显降低,10^(3)~10^(4)J以上微震事件明显减少且微震的空间分布较为分散,顶板附近微震事件明显减少,说明采取的卸压措施效果明显,可有效降低冲击危险性。
In order to further study the rock burst prevention technology under the specific geological conditions of hard-thick roof strata,the rock burst process of the overlying hard-thick roof strata in the mining process of I010203 working face of a mine was analyzed,the corresponding technical measures were put forward,and the effect of the prevention technology based on the temporal and spatial variation law of ME(micro earthquake) events before and after the pressure relief and erosion prevention of the working face was tested.The results show as follows:after the mining of B;coal seam,the overlying hard-thick roof strata was easy to form hanging roof in the goaf of I010203 working face and the coal pillar area between the I010201 goaf.It would cause the static load stress concentration of coal body,and energy accumulation,resulting in a lot of dynamic load.When the length of hanging roof was too long,strong dynamic load disturbance such as caving and breaking would occur,when the superposition of dynamic load and static load exceeded the critical value,rock burst would occur.The concentrated static load of coal pillar and the dynamic load of hard roof strata breaking were the main controlling factors of rock burst.According to the above analysis results of rock burst,two kinds of pressure relief technical measures(roof breaking pre-splitting and advance coal blasting) were designed.The ME events during stable production period before and after pressure relief were selected for comparative analysis of pressure relief effect.It is found that after pressure relief,the daily total energy and frequency of ME events are significantly reduced,and the ME events above 10^(3)~10^(4)J are significantly reduced,and the spatial distribution of ME events is relatively scattered.The ME events near the roof are significantly reduced,which indicates that the pressure relief measures can effectively reduce the rock burst hazard.
作者
孙秉成
兰世瑞
张传玖
李振雷
李红平
杨旭
贾兵兵
SUN Bing-cheng;LAN Shi-rui;ZHANG Chuan-jiu;LI Zhen-lei;LI Hong-ping;YANG Xu;JIA Bing-bing(Kuangou Coal Mine,Shenhua Xinjiang Energy Co.,Ltd.,Hutubi 831200,China;School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《煤炭工程》
北大核心
2022年第3期99-104,共6页
Coal Engineering
基金
国家重点研发计划项目(2016YFC0801408)。
关键词
坚硬厚顶板
冲击地压
顶板卸压
煤体卸压
微震事件
hard-thick roof
rockburst
roof pressure relief
coal body pressure relief
micro earthquake event
