深埋隧洞岩爆防控技术及典型工程应用现状综述

Review on Rockburst Prevention Techniques and Typical Applications in Deep Tunnels

结合岩爆的分类、机制、评价预警方法及防控原则,对深埋隧洞施工期岩爆主动和被动防控措施进行了梳理,重点分析其作用机理、适用范围与防控效果。对比了钻爆法和全断面隧道掘进机(TBM)法施工下岩爆的不同特征规律及防控重点,调研了典型水工隧洞的岩爆防控技术应用情况,包括锦屏二级水电站引水隧洞、引汉济渭工程秦岭隧洞、N-J水电站引水隧洞和滇中引水工程香炉山隧洞。结果表明:岩爆的主动防控措施包括钻孔应力释放、超前应力解除爆破、先导洞、高压喷水、钻孔注水、超前锚杆和预应力锚杆支护;被动防控措施包括喷锚支护、钢支撑、钢筋网(柔性钢丝网);钻爆法的岩爆防控重点是及时封闭支护,TBM法则需通过主动防控规避强烈-极强岩爆;当前大型水工隧洞的岩爆防治普遍采取主动+被动联合防控,主动措施以超前应力释放为核心,被动措施则采取“喷锚网+钢拱架”共同加固围岩,且注重使用快速柔性支护型式;岩爆的动态防控、量化精准防控以及发展更高效的超前应力释放技术和柔性吸能支护体系是值得进一步研究的方向。

The classification,mechanism,evaluation,prediction methods and prevention principles of rockburst are briefly introduced first.On this basis,active and passive prevention and control techniques for rockburst during deep tunnel construction are summarized.In particular,the mechanism,application scope and prevention effects of such measures are highlighted.The differences of rockburst characteristics between drilling and blasting(D&B)method and tunnel boring machine(TBM)method are analyzed,and the applications of rockburst prevention techniques in typical projects are investigated.Such projects include the diversion tunnel of Jinping II hydropower station,the Qinling tunnel of Hanjiang-to-Weihe River Diversion Project,the diversion tunnel of Neelum-Jhelum(N-J)hydroelectric project in Pakistan and Xianglushan tunnel of the diversion project in Central Yunnan.1)Active rockburst prevention techniques include borehole stress release,advanced stress relief blasting,pilot tunnels,high-pressure water injection,advanced anchor bolts and pre-stressed anchor bolts;passive prevention techniques include shotcrete-bolt support,steel support and reinforcement mesh(flexible steel wire mesh).2)Timely closed support and active measures against strong-extremely-strong rockburst are the key points of preventing rockburst induced by D&B method and TBM method,respectively.3)At present,active and passive measures are combined for the rockburst prevention of large hydraulic tunnels.For active prevention,advance stress release is the dominant measure,while for passive prevention,shotcrete-bolt-mesh combined with steel support is adopted together with the use of fast flexible support.4)Dynamic prevention,precise quantitative prevention,and more efficient advanced stress release technology and flexible energy absorption support system are research directions in future.