拱形沿空巷道破坏特征与控制技术

(1.甘肃靖远煤电股份有限公司 魏家地煤矿,甘肃 平川 730923; 2.西安科技大学 能源学院,陕西 西安 710054; 3.西安科技大学 矿山动压研究所,陕西 西安 710054)

拱形断面; 沿空掘巷; 煤柱; 破坏特征; 锚杆

Failure characteristics of roadway driving along goaf with crowned section and its control technology
WANG Qing-dan1,WANG Hong-sheng2,3,LI Lei2,3,ZHAO Si-hai1,CHONG Lei-gang1,LI Pei-cheng1

(1.Weijiadi Coal Mine,Gansu Jingyuan Coal Industry & Electricity Power Co.,Ltd.,Pingchuan 730923,China; 2.College of Energy Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China; 3.Institute of Dynamic Pressure in Mine,,Xi'an University of Science and Technology,Xi'an 710054,China)

crowned section; roadway driving along goaf; coal pillar; failure characteristics; bolt

DOI: 10.13800/j.cnki.xakjdxxb.2019.0107

备注

针对倾斜厚煤层拱形沿空巷道围岩控制难题,以魏家地煤矿2303工作面运输巷为工程背景,采用数值分析的方法,对其围岩应力分布、变形与破坏规律进行了探讨。结果 表明:煤柱内存在水平位移的零分界线,分界线采空区侧煤体破坏形式主要为拉剪混合破坏,另一侧煤体破坏形式主要为剪切破坏,煤柱稳定性差,实体煤帮角应力集中系数高达3.0且作用范围大,顶板岩体沿弱面发生剪切滑移,压剪破坏严重。提出“两区一让”围岩控制技术:短锚索抑制分界线附近煤柱分离,长锚索抑制煤体沿煤岩接触面剪切滑移,并采用木托盘整体让压,数值分析结果表明顶板下沉量减少40%,煤柱帮移近量减少50%,实体煤帮移近量减少44.4%,成功应用于控制实践。

Aiming at the problem of surrounding rock control of arched roadway along inclined thick coal seam,and taking the 2303 working face transportation lane of Weijiadi coal mine as the engineering background,the stress distribution,deformation and failure law of surrounding rock were discussed by numerical analysis method.The results show that there is a zero boundary line of horizontal displacement in the coal pillar,and the main failure mode of the side coal body in the goaf of the boundary line is the tensile-shear mixing failure.The main failure form of the other side coal body is shear failure,and the stability of the coal pillar is poor.The stress concentration factor of the coal-supporting angle is as high as 3.0 and the range of action is large.The shearing slip of the roof rock mass along the weak surface occurs,and the compression-shear damage is serious.The surrounding rock control technology of “two zones and one yield” is proposed:the short anchor cable restrains the separation of coal pillar near the boundary line,and the long anchor cable restrains the shear slip of the coal body along the coal rock contact surface,and the wooden pallet is used to yield.The numerical analysis results show that the roof subsidence is reduced by 40%,the coal pillar convergence is reduced by 50%,and the physical coal convergence is reduced by 44.4%,which has successfully been applied to control practice.