采区坚硬岩层动力灾害致灾能量演化及充填弱化机理研究  

Energy evolution and backfilling weakening mechanism of hard rock strata causing dynamic disasters in coal mining

作　　者：周楠 李泽君 张吉雄 李百宜 闫浩 ZHOU Nan;LI Zejun;ZHANG Jixiong;LI Baiyi;YAN Hao(School of Mines,Key Laboratory of Deep Coal Resource Mining,Ministry of Education,China University of Mining and Technology,Xuzhou,Jiangsuu221116,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China)

机构地区：[1]中国矿业大学矿业工程学院,深部煤炭资源开采教育部重点实验室,江苏徐州221116 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116

出　　处：《采矿与安全工程学报》2023年第5期1078-1091,共14页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(52130402)。

摘　　要：坚硬岩层变形破断是引起工作面动力灾害的主要原因之一,充填弱化坚硬岩层致灾能量是防治坚硬顶板型动力灾害的有效手段。为进一步研究采区坚硬岩层动力灾害致灾能量演化及充填弱化机理,以内蒙古某矿八采区为例,采用理论分析与数值模拟相结合的方法,分析了采区坚硬岩层破断特征和不同开采方案下的动力致灾能量演化规律,得到了采区多工作面开采坚硬岩层动力灾害危险性及充填弱化因素。研究表明:高位坚硬岩层断裂尺寸由采区走向与倾向开采长度共同决定;采区第2个工作面开采时,坚硬岩层动力灾害危险性明显增加;当充填体与顶板同侧未接触面积小于或等于1个工作面时,充填开采可以有效减小煤体与坚硬岩层的积聚能量,弱化采区坚硬岩层动力灾害,不同充填方案弱化动力灾害效果排序为:全采全充>采3充2(间隔工作面充填)>采3充2(连续工作面充填)>采3充1(中间工作面充填)>采3充1(两侧工作面充填)。Deformation and breakage of hard rock strata is one of the main causes for dynamic disasters in longwall panel mining,and the use of backfilling to weaken the disaster-caused energy is an effective method for the prevention of hard roof related dynamic disasters.In order to further study the energy e-volution and backfilling weakening mechanism of hard rock strata causing dynamic disasters in coal min-ing district,taking the eighth mining area of a coal mine in Inner Mongolia as an example,a combina-tion of theoretical analysis and numerical simulation was adopted to analyze the fracture characteristics of hard rock strata in coal mining district and the energy evolution caused by the dynamic disaster in differ-ent mining plans.The risk potential of hard rock strata causing dynamic disasters in multiple working faces and the associated influencing factors of backfilling weakening was obtained.The research shows that the fracture size of high-overburden hard rock strata is codetermined by the strike of mining area and the inclined mining length.In the mining process of the second longwall panel in a mining district,the risk degree of dynamic disasters caused by hard rock layers significantly increases.When the contactless area between the filling body and the roof in the same side is less than or equal to the width of one longwall panel,backfilling mining can effectively reduce the energy accumulation of the coal seam and the hard rock strata,which could weaken or migrate the hard rock strata causing dynamic disaster.The weakening effects of the dynamic disaster from different backfilling schemes are ranking in:full mining>3 full mining within 2 backfilling(interval backflling)>3 full mining within 2 backfilling(continuous backfilling)>3 full mining within 1 backfilling(backfilling in the middle)>3 full mining within 1 backfilling(backfilling in two sides).

关 键 词：坚硬岩层 破断尺寸 动力灾害 充填开采 数值模拟 

分 类 号：TD821[矿业工程—煤矿开采]