高预紧力锚杆(索)在大断面复合顶板巷道的应用研究

Application Research of High Pre-tightening Force Bolt(Cable)in Large Section Roadway with Composite Roof

以大断面复合顶板巷道为研究对象,采用围岩探测技术和数值模拟分析,对复合顶板大断面巷道的围岩稳定性控制进行了研究,通过分析原巷道支护存在的问题,提出了高预紧力锚杆(索)支护设计思路,并对巷道支护方案进行了优化。现场试验表明:试验巷道两帮累计移近量570 mm,顶底板累计变形量352 mm,其中,回采期间变形量分别占82.3%和77.2%;锚杆(索)施加高预紧力后,能够有效控制巷道围岩初期产生大变形,使巷道围岩尽快达到平衡状态,充分发挥支护结构的承载作用;巷道能够满足使用要求。

Detection technology and numerical simulation were used to study the stability control of the surrounding rock in large-section roadways with composite roof;on the analysis of the problems in the original roadway support,the design of high pre-tightening bolt(cable)support was put forward and the roadway support plan was optimized.The field test showed that the cumulative convergence of the two sides of the test roadway was 570 mm,and the cumulative deformation of the roof and floor was 352 mm.The deformation during caving accounted for 82.3%and 77.2%respectively.Applying high pre-tightening force to the bolt(cable)can effectively control the large deformation of the surrounding rock at the initial stage and make the surrounding rock reach a balanced state as soon as possible.The supporting structure can give full play to the bearing capacity so that the roadway can meet the requirements.