断层岩柱瓦斯超前突出机理数值模拟及防护厚度  

Numerical simulation and its prevention thickness of gas advance-outburst mechanism in faults rock pillar

作　　者：王志荣[1] 王泉更 陈玲霞[1] 李亚坤[1] 

机构地区：[1]郑州大学水利与环境学院,河南郑州450001

出　　处：《河南理工大学学报（自然科学版）》2016年第3期289-296,共8页Journal of Henan Polytechnic University（Natural Science）

基　　金：国家自然科学基金资助项目(41272339)

摘　　要：针对矿井巷道掘进面前方遭遇含瓦斯断层时,安全岩柱内的沉积界面将会遭受气体损伤作用的问题,通过ABAQUS软件的二次开发,基于流-固耦合理论和T-P损伤演化准则的cohesive单元,对豫西大平煤矿21轨道下山一次大型瓦斯突出事故进行数值模拟。计算结果表明：由于受巷道开挖所产生的二次应力与断层带瓦斯压力的共同作用,前方岩柱内两个沉积界面将优先产生损伤软化现象。随着巷道向断层带的推进,气体的侵蚀作用不断加强,沉积界面的损伤急剧增加并向掘进面延伸。当掘进面距离前方断层分别为19,17,15 m时,上层面相应产生6.2,9.7,13.4 m长的损伤裂隙;下层面相应延伸距离较短,仅产生4.1,4.6,4.8 m长的损伤裂隙。与此同时,上层面瓦斯急剧渗透扩展,在掘进面前方1-2 m处开始出现3.5 MPa的孔隙气压升高带。由此可见,界面差异性强的上层面相对较弱的下层面容易损伤,而且损伤后的沉积界面优先产生相应的渗流扩散现象。当损伤沉积界面最终贯通掘进面与断层面之间的岩柱,即裂隙损伤长度达到极限岩柱安全厚度时,瓦斯将突破岩体阻抗并产生冲击地压。When tunnel face of mining meets gas-bearing fault, sediment interface in rock pillar will be damagedby gas. Based on flow-solid theory and cohesive unit of T-P damage evolution standards, numerical simulationof a large scale gas outburst accident in the slant of track 21 of Daping coal mine in Western Henan wasconducted by secondary development of ABAQUS. The results showed that the two sediment interface in rockpillar were first damaged because of the combined effect of gas pressure in fault zone and secondary stresscaused by tunnel excavation. As the tunnel was excavated to fault zone,the erosion of gas turned to be strengthenand the damage of sediment interface increased sharply and extended to the tunnel face, but the damageeffect of different levels were not the same. When the distance between excavation surface and fault zone were 19,17,15 m,the upper level produced corresponding damage cracks which were 6. 2 ,9. 7 ,13.4 m at length,while the cracks in lower level were shorter and the length of them were 4 . 1 ,4 . 6 ,4 . 8 m. At the same time,the gas penetration dramatically extended and high pore pressure zone with a value of 3.5 MPa began to appearat the place 1 -2 m away before excavation surface. The calculation results indicated that the upper level waseasily damaged which it had a strong interface difference and the crack surface after damage. When the cracks are eventually through the rock pillars between tunnel face and fault plate, namely the length of cracks reaches the safe thickness of rock pillars, the gas will break through the impedance of rock and produce impact pressure.

关 键 词：沉积界面 损伤软化 瓦斯渗透扩展 超前突出 岩柱安全厚度 

分 类 号：TD713[矿业工程—矿井通风与安全]