顶部导洞法TBM卡机脱困技术研究与应用

Research and Application of Top Pilot Tunnel Method Rescue Technology in TBM Jamming

研究目的:TBM已在我国地下工程建设领域中得到广泛应用,但对于复杂地质条件,TBM卡机问题仍十分突出,施工中曾多次遭遇连续卡机、长期卡机、突水涌泥、设备报废、工法改变等不同程度的困难,不但造成工期延误,还使工程建设成本大幅度增加,因此研究复杂地质条件下TBM卡机防控技术以及TBM卡机后的安全快速脱困技术十分必要。高黎贡山隧道全长34538 m,进口采用钻爆法施工,出口采用TBM法施工。TBM施工中,一般地质条件下掘进比较顺利,但遇到断层破碎带、岩性接触带、节理密集带、风化蚀变带、软岩挤压带等复杂地质条件时,仍发生了19次卡机事故,其中正洞8次、平导11次,严重影响TBM的正常掘进,特别是严重卡机时,常规的脱困方法难以奏效,需要研究安全有效的脱困技术,从而保证TBM的正常掘进。研究结论:(1)顶部导洞法是处理TBM卡机的一种有效脱困方法;(2)采用顶部导洞法处理TBM卡机时,导洞净空宽度宜为120 cm、净空高度宜为130 cm,管棚工作间宜在拱部120°范围内设置,管棚直径宜为76 mm,环向间距40 cm,仰角1°~3°,长度宜一次穿越隧道前方破碎带;(3)本研究成果可在类似隧道TBM施工中推广应用。

Research purposes:TBM has been widely used in the field of underground engineering construction in China,but for complex geological conditions,the problem of TBM jamming is still very prominent.During construction,it has encountered difficulties in varying degrees such as continuous jamming,long-term jamming,water and mud inrush,equipment scrapping and construction method change,which not only delayed the construction period,but also greatly increased the project construction cost.Therefore,it is very necessary to study the prevention and control technology of TBM jamming under complex geological conditions and the safe and rapid escape technology after TBM jamming.Gaoligongshan Tunnel is 34538 m in length.The inlet is constructed by drilling and blasting method,and the outlet is constructed by TBM method.During TBM construction,tunneling is relatively smooth under general geological conditions,but when the complex geological conditions such as the fault fracture zone,lithologic contact zone,joint dense belt,weathering alteration belt and soft rock extrusion zone are encountered,there are still 19 times jamming accident including 8 positive holes and 11 flat guide,seriously affecting the normal TBM tunneling,especially serious jamming,the conventional methods are difficult to be effective,so it is necessary to study safe and effective techniques to ensure the normal tunneling of TBM.Research conclusions:(1)The top pilot tunnel method is an effective way to deal with TBM jamming.(2)When the top pilot tunnel method is used to deal with TBM jamming,the headroom width of the pilot tunnel should be 120 cm and the headroom height should be 130 cm.The pipe shed workshop should be set within 120°of the arch.The pipe shed should have a diameter of 76 mm,a circumferential spacing of 40 cm,an elevation of 1°~3°,and the length should pass through the fracture zone in front of the tunnel at one time.(3)The research results can be popularized and applied in TBM construction of similar tunnels.