复杂地质条件下TBM卡机原因及脱困措施研究

Study on the Cause of TBM Jam and Its Relief Measures under Complex Geological Condition

为解决高黎贡山隧道正洞断层破碎带TBM无法掘进的难题,针对掌子面围岩呈泥沙状、盾体周边围岩破碎的问题,提出采用超前地质预报的方法进行地质探测。首先判断前方围岩地质特性,然后采取化学注浆的方法对盾体周边及掌子面进行注浆加固。针对露出护盾的破碎围岩、刀盘出现超量出渣的问题,提出盾尾破碎围岩加强初期支护、刀盘底部清渣及刮渣口进行加密的方法来进行应对处理;进一步就破碎围岩处理问题提出采用小导洞扩挖、掌子面化学注浆的方法对破碎岩体及刀盘前方的破碎围岩进行处理,通过实践验证,采取上述方法可以有效地实现TBM脱困。TBM脱困方法可为TBM在破碎地层掘进中提供有效的规避措施,也可为其他类似工程处理TBM卡机问题提供借鉴。

In order to solve the problem that TBM can’t be excavated in the fracture zone of the main tunnel of Gaoligongshan Tunnel, an advanced geological prediction method is proposed for geological exploration in view of fact that the surrounding rock of the face is sandy and the surrounding rock of the shield body is broken,. First, the geological characteristics of the surrounding rock in front of the shield body are judged, and then chemical grouting method is adopted for the surrounding rock of the shield body. Grouting reinforcement is carried out on the tunnel face. Aiming at the problem of excessive slag discharged from the broken surrounding rock and the cutter head exposed to shield, the methods of strengthening the initial support of the broken surrounding rock at the tail of shield, clearing slag at the bottom of the cutter head and reinforcing the scraper are put forward. Furthermore, the problem of treating the broken surrounding rock is solved by using small pilot tunnel expansion and excavation. The chemical grouting method on the tunnel face is used to treat the fractured rock mass and the fractured surrounding rock in front of the cutter head. Practices prove that the above-mentioned methods can effectively realize TBM extrication. TBM relief method can not only provide effective evasive measures for TBM in fractured stratum excavation, but also provide reference for other similar projects to deal with TBM stuck.