深部回采巷道锚固失效分析及支护对策  

Analysis of bolting failure in deep mining roadway and support countermeasures

作　　者：宁义国 马双文 CAO Chen NING Yiguo;MA Shuangwen;CAO Chen(Lvjiatuo Mining Company,Kailuan Co.,Ltd.,Tangshan 063107,China;College of Mining,Liaoning Technical University,Fuxin 123000,China;School of Civil,Mining and Environmental Engineering,University of Wollongong,Wollongong 2522,Australia)

机构地区：[1]开滦能源化工股份有限公司吕家坨矿业分公司,河北唐山063107 [2]辽宁工程技术大学矿业学院,辽宁阜新123000 [3]伍伦贡大学土木、采矿与环境学院,新南威尔士伍伦贡2522

出　　处：《煤炭科学技术》2021年第8期23-29,共7页Coal Science and Technology

基　　金：深部岩土力学与地下工程国家重点实验室开放基金资助项目(SKLGDUEK1927)。

摘　　要：针对深部回采巷道围岩变形导致锚杆支护失效的问题,提出通过改善锚杆受力状态、改变锚杆锚固方式、优化杆体形状,减少锚杆破断的方法,在此基础上,设计了1种新外形结构的螺纹钢锚杆。进行了实验室拉拔试验,结果表明:矿用右旋锚杆、左旋锚杆和大肋间距高强锚杆的平均拉拔力为136.9、106.1、147.6 kN,且大肋间距高强锚杆吸能效果更好。在现场试验前,先对回风巷的围岩结构进行探测,包括顶板钻孔窥视和松动圈测试,依据围岩结构探测结果,确定最终的巷道支护方案。回风巷采用原支护方案和大肋间距高强锚杆全锚支护2种方案支护,并对顶板离层和锚杆受力进行实时监测,试验结果表明:大肋间距高强锚杆支护的巷道顶板最大下沉量较原支护方案减小36.4%,顶板离层量较原支护方案降低24.1%;顶板和两帮锚杆受力的结果显示大肋间距高强锚杆支护较原支护方案锚杆受力更小,两种支护方案顶板锚杆受力最大值分别为442.9 MPa和78.1 MPa,改进方案较原支护方案降低了82.4%;其回采期间,全锚大肋间距高强锚杆支护方案与原支护方案相比,支护失效锚杆数量明显减少,这都表明全长锚固的大肋间距高强锚杆更有利于维护巷道的稳定。Aiming at the problem of bolt support failure caused by surrounding rock deformation in deep mining roadway,a method was proposed to reduce the bolt breakage by improving the bolt stress state,changing the anchoring mode and optimizing the shape of rod body.On this basis,a new rebar anchor rod with a new shape and structurewas designed.Laboratory tests show thatthe average pull-out force of the right-hand bolt,the left-hand bolt and the high strength bolt with large rib spacings are 136.9 kN,106.1 kN and 147.6 kN,andthe large-rib spacing high-strength bolts absorb energy better result.Before the field test,the surrounding rock structure of the return air roadway was detected,including roof drilling and loose circle testing.The final roadway support scheme was determined according to the detection results of surrounding rock structure.The original supporting scheme and full bolt supporting scheme were adopted for the return roadway,and the roof separation and bolt stress were monitored in real time.The test results show that the maximum roof subsidence of roadway supported by high-strength bolt with large rib spacing is reduced by 36.4%compared with the original support scheme,and the roof separation amount is reduced by 24.1%compared with the original support scheme.The results of the stress on the roof and two side bolts show that the stress of high-strength bolt with large rib spacing is smaller than that of the original support scheme,and the maximum stress of roof bolt is 442.9 MPa and 78.1 MPa respectively,and the improved scheme is reduced by 82.4%compared with the original support scheme.At the same time,compared with the original support scheme,the failure of bolt support is significantly reduced,which indicates that the full-length anchored high-strength boltwith large rib spacingis more conducive to maintain the stability of roadway.

关 键 词：锚杆支护 锚固方式 巷道变形 深部回采 

分 类 号：TD353[矿业工程—矿井建设]