摘要
随着我国煤炭资源开采战略西移,西部部分矿井已进入深部开采阶段,邻空巷道冲击失稳频繁发生,严重威胁煤矿安全生产。以新街矿区红庆河煤矿为工程背景,综合运用现场调研、理论分析和数值模拟等方法对新街矿区深部开采邻空巷道受载特征及冲击失稳机制进行研究。建立了初次来压、充分采动阶段工作面前方邻空巷道动静载叠加力学模型;通过精细描述不同阶段静载及扰动动载,提出了基于采空区侧向静载、超前静载及扰动动载的邻空巷道“三载荷”动静叠加原理,并给出了发生冲击失稳的应力判据;揭示了邻空巷道围岩受“三载荷”叠加诱冲机制,即高应力、能量经巷道“顶—帮—底”传递,巷道围岩形成应力集中,能量积聚,达到煤岩体冲击失稳临界值时,诱发邻空巷道冲击失稳。针对工作面上覆厚硬岩层的邻空巷道冲击地压灾害,提出了“切断动载源、降低集中静载应力和恒阻大变形吸能锚杆锚固”的防治措施。研究结果表明:邻空工作面初次来压阶段相邻双工作面采空区顶板形成非对称“T”型结构,亚关键层Ⅰ破断,亚关键层Ⅱ未破断,工作面来压较缓和,邻空巷道围岩所受静载较大,扰动动载较小;周期来压(充分采动)阶段相邻双工作面采空区顶板形成对称“T”型结构,两组亚关键层均破断,邻空巷道围岩所受静载及扰动动载均较大,此时易诱发邻空巷道冲击失稳。
The main mining areas of coal resources are moving to the western China,some western mines reach a deep mining level.The coal burst of gob side roadway occurs frequently,which threatens the safe mine production seriously.In this paper,the characteristics of ground pressure and mechanism of coal burst in the gob side roadway at Xinjie deep mining area is studied by site investigation,theoretical analysis and numerical simulation.The mechanical model of gob side roadway in front of longwall face under the dynamic and static combined loading is established.This model focuses on the initial weighting and full mining stages.The principle of dynamic and static combined loading for the gob side static load,the front abutment pressure and the mining induced dynamic load is proposed by finely describing the static load and mining induced dynamic load in different stages.The stress criterion of coal burst of gob side roadway is provided.The mechanism of coal burst of the gob side roadway is discovered,the high stress and energy will transfer from the roof strata to the rib and floor of roadway,which can result in the stress concentration and energy accumulation.As the stress and energy reaches the threshold value of the coal burst,the coal burst in gob side roadway will occur.Moreover,as far as the coal burst disaster in gob side roadway with thick and hard stratum in the roof,the prevention methods for coal burst are proposed.The method consists of“cutting off the dynamic load sources”,“reducing the static load stress concentration”and“using energy absorption bolt anchorage with constant resistance at large deformation”.The results show that the gob roof of adjacent double longwall faces can form asymmetrical T-type structure when the initial weighting stage in gob side longwall face,the sub-key stratum(SKS)I is broken,but the SKS II is not broken.The roof weighting of longwall face is small,the static load in the surrounding rock of gob side roadway is large,and the mining induced dynamic load is relative small.However,the gob roof of adjacent double longwall faces can form a symmetrical T-type structure at the periodic weighting(full mining)stage.The double sub-key stratums are broken,the static load and mining induced dynamic load are both larger in the surrounding rock of gob side roadway,which can induce a coal burst in gob side roadway easily.
作者
赵毅鑫
周金龙
刘文岗
ZHAO Yixin;ZHOU Jinlong;LIU Wengang(Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources,China University of Mining and Technology (Beijing),Beijing 100083,China;School of Energy and Mining Engineering,China University of Mining and Technology (Beijing),Beijing 100083,China;Research Institute of Emergency Science,China Coal Research Institute,Beijing 100013,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2020年第5期1595-1606,共12页
Journal of China Coal Society
基金
国家重点研发计划资助项目(2016YFC0801401)
国家自然科学基金资助项目(51874312,U1910206)。
关键词
新街矿区
邻空巷道
顶板结构
动静载
冲击失稳
Xinjie mining area
gob side roadway
roof structure
dynamic and static load
coal burst