采用小直径TBM进行长大隧道导洞施工的讨论

介绍采用小直径开敞式TBM进行超前平导施工的意义、目的和国外采用小直径TBM进行超前导洞施工的实例；分析国内采用小直径开敞式TBM进行超前导洞施工的可行性；总结进行超前导洞施工时选择开敞式TBM的考虑因素。得出以下结论：利用小直径开敞式TBM进行长大隧道超前导洞施工，符合国家对基本建设的环保和安全的要求；当前的综合国力和施工技术水平也具备了相应的条件；选择小直径TBM时应考虑其特点，并满足“快速掘进、探明地质、支持正洞”的要求。

Discussion on Construction of Pilots of Long and Large Cross-section Tunnels Bored by Small-diameter TBMs

The significance and targets of pilot tunnels constructed by small-diameter open TBMs are presented,cases of pilot tunnels constructed by small-diameter open TBMs abroad are listed,the feasibility to build pilot tunnels by small-diameter open TBMs is analyzed and factors to be considered in the selection of small-diameter open TBMs in the construction of pilot tunnels are summarized.Conclusions drawn are as follows： 1） The concept to build pilot tunnels by small-diameter open TBMs meets the requirements of the state for the infrastructure construction in terms of environment protection and safety;2） The comprehensive national capability and the construction technologies have reached the relevant requirements;3） The features of small-diameter open TBMs should be taken into full consideration and the requirements of rapid boring,geology probing and assistance to the main tunnel construction should be satisfied.