含软弱夹层综放工作面煤帮大变形机理及其控制  

Mechanism and control of large deformation of coal wall in fully mechanized top-coal caving face with weak interlayer

作　　者：惠凡光 潘兴松 孔祥玉 王阁 孙启果 周宝龙 HUI Fanguang;PAN Xingsong;KONG Xiangyu;WANG Ge;SUN Qiguo;ZHOU Baolong(Dongtan Coal Mine,Yankuang Energy Group Co.,Ltd.,Jining 273500,China;Taishuo Strata Control Technology Co.,Ltd.,Taian 271000,China)

机构地区：[1]兖矿能源集团股份有限公司东滩煤矿,山东济宁273500 [2]泰安泰烁岩层控制科技有限公司,山东泰安271000

出　　处：《煤矿安全》2023年第9期137-146,共10页Safety in Coal Mines

摘　　要：含软弱夹层煤帮常出现大变形问题,影响巷道的正常使用。以东滩煤矿3308工作面轨道巷为研究背景,综合采用现场实测,数值模拟,理论分析等手段,分析含软弱夹层巷道帮部的大变形特征,基于莫尔-库仑强度准则研究其失稳机理,得到煤柱发生剪切破坏的判据表达式,探讨围岩力学参数对大变形的影响规律。结果表明:两帮水平位移的峰值在软弱夹层处,软弱夹层是煤帮发生大变形的关键因素;含软弱夹层煤帮发生大变形对锚杆所产生的轴向拉力不足以使锚杆(索)杆体发生破坏,锚杆(索)承载能力的丧失可能由于锚固区黏聚力低或尾部脱锚;通过提高围岩内摩擦角和黏聚力可使剪切带范围减小甚至避免发生剪切破坏。基于研究成果,提出了锚索注浆改性、摩擦让压锚杆适应大变形及锚杆尾部增锚、限位抗剪锚杆补强的支护原则并进行了工程验证。Large deformation often occurs in the coal wall with weak interlayer,which affects the normal use of the roadway.Based on the research background of the track channel of 3308 working face in Dongtan Coal Mine,the large deformation characteristics of the side of the roadway with weak interlayer are analyzed by means of field measurement,numerical simulation and theoretical analysis,and its instability mechanism is studied.The criterion expression of the shear failure of the coal pillar is obtained,and the influence law of the surrounding rock mechanical parameters on the large deformation is discussed.The results show that the peak value of the horizontal displacement of the two sides is at the weak interlayer,which is the key factor for the large deformation of the coal side;the axial tension produced by the large deformation of the coal wall with weak interlayer on the anchor rod is insufficient to destroy the anchor rod(cable)body.The loss of the bearing capacity of the anchor rod(cable)may be due to the low cohesion of the anchorage zone or the tail detachment of the anchor;by increasing the internal friction angle and cohesion of surrounding rock,the range of shear band can be reduced and even the specific plane can be sheared.Based on the research results,the supporting principles of grouting modification of anchor cable,adaptation of pressure bolt by friction to large deformation,adding anchor at the end of bolt,and reinforcement of shear bolt with limited position are proposed and verified by engineering.

关 键 词：软弱夹层 大变形 失稳机理 剪切破坏 综放工作面 

分 类 号：TD322[矿业工程—矿井建设]