摘要
深部综采工作面多关键层-煤柱系统失稳型冲击地压是鄂尔多斯深部矿区常见的冲击地压类型,目前现场没有统一成熟的治理方案,冲击显现仍时有发生,以鄂尔多斯深部矿区门克庆矿3102工作面为工程背景,采用理论分析、数值模拟、现场实测等方法,对深部综采工作面多关键层-煤柱系统失稳诱冲机理进行研究,探讨了深部多关键层-煤柱系统的空间结构演化规律,研究了区段煤柱承载多关键层加载模式,分析了多关键层-宽煤柱系统的变形与应力转化函数关系,推导了多关键层-宽煤柱系统的失稳冲击工程判据。揭示了深部多关键层-煤柱系统失稳诱冲机理:当煤柱两侧采空区后,低位“ILZ”和面内“DLZ”破断关键岩层组加载至宽煤柱使其压缩变形,之后采场“DLZ”关键岩层组挠曲甚至破断,转移应力加载区段煤柱上,当其承载应力超过失稳阈值时即发生整体失稳冲击。数值模拟研究了不同缩面宽度条件下的采场区段煤柱应力大小与分布特征变化规律,随着区段承载煤柱宽度的增加,应力分布特征由平台型过渡至马鞍形,应力集中程度和整体冲击危险水平持续降低,现场实测验证了120 m区段煤柱的防冲安全性。
The instability type of rock burst in the multi key strata coal pillar system of the deep fully mechanized mining face is a common type of rock burst in the deep mining area of Ordos.Currently,there is no unified and mature treatment plan,and the rock burst stll occurs from time to time.The 3102 working face of a coal mine in the deep mining area of Ordos was taken as the engineering background,and theoretical analysis,numerical simulation,and on-site measurement were conducted,to study the rock burst mechanism induced by instability of the multi key strata coal pillar system.The spatial structural evolution law of the deep multi key strata coal pillar system was explored,the loading mode of the district coal pillar bearing multi key strata was studied,the deformation and stress transformation function relationship of the multi key strata wide coal pillar system was analyzed,and the engineering criterion for instability induced rock burst of the system was derived.The instability induced rock burst mechanism of the deep multi key strata coal pillar system was revealed:when both sides of the coal pillar is mined out,the low level"ILZ"and in-plane"DLZ"key broken rock group is loaded on wide coal pillar and lead to the compression deformation.Afterwards,the"DLZ"key rock group in the stope flexes or even breaks,transferring stress to the loading section of the coal pillar.When its bearing stress exceeds the instability threshold,the overall instability rock burst occurs.Numerical simulation was conducted to study the changes in stress magnitude and distribution characteristics of coal pillars in different shrinkage width conditions in the mining area.As the width of the bearing coal pillars in the section increases,the stress distribution changes from a platform-shape to a saddle-shape,and the degree of stress concentration and overall rock burst risk level continue to decrease.Field measurements have verified the anti-burst effect of the 120 m district coal pillar.
作者
杨光宇
陈学慧
周宏伟
YANG Guangyu;CHEN Xuehui;ZHOU Hongwei(CCTEG Coal Mining Research Institute Co.,Ltd.,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization,Beijing 100013,China)
出处
《煤炭工程》
北大核心
2024年第5期121-128,共8页
Coal Engineering
关键词
多关键层
煤柱
冲击地压
整体失稳
微震监测
multiple key strata
coal pillar
rock burst
overall instability
microseismic monitoring
