急斜煤层残留高阶段煤柱动力失稳机理研究  

Study on dynamic destabilization mechanism of residual high-stage coal pillar in inclined coal seam

作　　者：曹建涛[1] 来兴平[1] 闫瑞兵 

机构地区：[1]西安科技大学能源学院,教育部西部矿井开采及灾害防治重点实验室,陕西西安710054

出　　处：《采矿与安全工程学报》2018年第1期133-139,共7页Journal of Mining & Safety Engineering

基　　金：国家重点基础研究发展计划(973)项目(2015cB251600);国家自然科学基金(煤炭联合基金)重点项目(U1361206)：国家自然科学基金项目(51504184)：博士培育基金项目(2014051)

摘　　要：针对乌东煤矿急斜特厚煤层综放工作面覆层残留高阶段煤柱动力失稳问题,采用变形失稳理论构建了覆层残留高阶段煤柱动力失稳力学模型,运用数值模拟分析了上覆高阶段残留高阶段煤柱动态失稳过程及应力演化规律,揭示了覆层残留高阶段煤柱动力失稳机理,提出了覆层残留高阶段煤柱诱发失稳防治措施,开展了基于微震监测的动力失稳防治效果评估。结果表明:急斜特厚煤层综放工作面推近及推过高阶段煤柱过程中形成的应力持续性高度集中是诱发动力失稳产生的力源;工作面前方的应力增高区与煤柱形成的应力集中区产生叠加效应,应力集中系数最高达到3.7倍;将距高阶段煤柱不同位置时工作面前方支承压力峰值划分为3个区域(平稳区、过渡区、叠加区),确定高阶段煤柱诱发动力失稳危险区在煤柱前方0~60 m。动力失稳防治实践表明:采取煤岩注水、卸压爆破耦合致裂措施对上覆残留高阶段煤柱解危,利用微震监测系统完成解危效果评估,保障工作面安全通过了上覆残留高阶段煤柱的危险区域。According to the dynamic instability problems of residual high stage coal pillar with the character of steep and extra-thick coal seam in the top-coal caving face of Wudong coal mine, the mechanical model of dynamic instability at residual high stage coal pillar is constructed by using deformation instability theory, the numerical simulation is used to analyze the instability process and force evolution in high residual high stage. We reveal the instability mechanism induced by the residual high stage coal pillar and put forward the preventive measures and carry out the control effect evaluation of dynamic instability based on microseismic monitoring. The results show that force source of inducing dynamic instability is the stress concentration with the character of highly persistent caused by the pro- cess of pushing in and pushing the high stage coal pillar; stress increasing zone in front of working face and coal pillar stress concentration zone show the superposition effect, stress concentration coefficient has a maximum of 3.7 times of the in-suit one; the abutment pressure peak is divided into three regions（stable region, transition region and the superposition region） from the high stage coal pillar to the posi- tion of working face, the danger zone of dynamic instability induced by high stage coal pillar is deter- mined in front of the pillar about 0-60 m away. The dynamic instability prevention practices show that the oberlying residual high stage coal pillar was done by the coupled-crack measures of coal injection and pressure relief blasting, the evaluation of controlling effect was completed by using microseismic monitoring system, which ensured the working face mining safely through the risk area of overlying re- sidual high stage coal pillar.

关 键 词：急斜特厚煤层 覆层残留煤柱 剪切滑移破坏 动力失稳 微震监测 

分 类 号：TD823[矿业工程—煤矿开采]