基于巷道围岩塑性区形态变化的变形破坏机理及支护  

Deformation Mechanism and Support of Roadway Based on Morphological Change of Plastic Zone

作　　者：姚琦[1] 冯涛[1] 王卫军[1] 余伟健[1] 袁超[1] 袁越[1] 

机构地区：[1]湖南科技大学煤矿安全开采技术湖南省重点实验室,湖南湘潭411201

出　　处：《矿业工程研究》2017年第2期37-44,共8页Mineral Engineering Research

基　　金：国家自然科学基金资助项目(51434006);湖南省教育厅科研资助项目(15C0551);湖南省煤矿安全开采技术重点实验室开放基金资助项目(201402)

摘　　要：为了研究围岩塑性区形态发展对巷道浅部围岩支护的影响,采用理论分析、数值模拟及现场试验,研究巷道塑性区形态的变化规律,分析巷道支护失效的原因,得出采动影响下的巷道修护建议.研究表明:(1)不同形态的巷道,在相同侧压系数条件下,产生的塑性区形态趋于一致;(2)在侧压系数(λ=0.1~1.0)的范围内,巷道围岩塑性区形态随着λ的减小而逐渐呈现"蝴蝶"形状;(3)在采动影响下,巷道开挖形成的"蝶"形塑性区始终与主应力方向呈相对一致性.针对木孔煤矿+700瓦斯抽放巷在采动影响下,原有塑性区发生了扩展性旋转,导致巷道的上帮部的锚杆锚固端由弹性区转至塑性区内,锚杆出现整体拉出失效,而锚索则是受力过大致其拉断失效.设计"巷道周边加固+部分加长锚杆(索)"作为巷道修帮支护方式,在修帮支护后的6个月巷道变形较小,达到了修帮支护目的.In order to study the influence of the development of plastic zone on the roadway support of shallow surrounding rock, this paper uses the theoretical analysis and numerical simulations and experiments to study the evolution of dynamic pressure roadway of plastic form, analyze the causes of failure of roadway, and set out under the influence of pressure roadway recommendations. Research results show that ： （ 1 ） when the side pressure coefficients are the same, the morphologies of plastic zone of different roadways are the same; （ 2） when the side pressure coefficients ranges from 0？ 1 ？1 .0 ,the morphology of plastic zone are “butterfly” with the decrease of side pressure coefficient; （ 3 ） when the angle between principal stress and horizontal changed, the “butterfly” plastic zone is always consistent with the principal stress direction. Aiming at the ＋700 gas drainage roadway under mine stress in Mukong Coal Mine, by the influence of working face mining above the gas drainage roadway, the original plastic zone of roadway is rotated and extended, resulting in the fact that the bolts of the side near the working face of the gas drainage roadway is in the plastic zone, and the surrounding rock of the roadway side near working face is overall instable. In addition, the cables are pulled off due to the high tensile force. Therefore, the support scheme of lengthening the bolts and cables is proposed, and the roadway deformation in 6 months after the repair and support of roadway is less, which achieves the goal of roadway support.

关 键 词：煤矿开采 塑性区 形态变化 主偏应力 破坏机理 巷道支护 

分 类 号：TD823[矿业工程—煤矿开采]