介绍导洞法的概念及其作用,分析导洞法的特点及其适用条件。以2座已建成运营的单洞双线铁路隧道和1座施工图设计阶段的双洞6车道高速公路隧道共3座地质差异较大的特长隧道为依托,主要进行以工期关键工序——挖掘和初期支护为研究对象的工期方案模拟,并比对模拟方案工期与实际或施工图设计工期。认为： 1）软弱破碎围岩比例高的单洞隧道应慎重采取TBM导洞法。2）仅用1台TBM单向导洞法取代工期性辅助导坑对单洞特长隧道而言是不可行的;在单洞特长隧道建设中,2台TBM相向实施TBM导洞法是可行的,但须具备设置辅助导坑的条件,辅助导坑宜按无轨双车道断面设置。3）在双洞特长隧道建设中,双洞各用1台TBM相向平行导洞法则有望取代工期性辅助导坑;双洞特长隧道实施TBM导洞法,在工期、成本(投资)、不良地质应对方面有明显优势。4）川渝地区广泛分布的泥岩、砂岩、砂质泥岩、泥质砂岩及其互层地层具有实施TBM导洞法的天然地质优势。最后对TBM导洞法的应用前景进行了展望。

In this paper, the concept and effect of pilotheading method are presented, and the characteristics and applicable conditions of pilotheading method are analyzed. The construction schedules of 3 tunnels located in different geological conditions are simulated in terms of excavation and primary support, and comparison and contrast is made between simulated construction schedules and actual/designed construction schedules. Conclusions drawn are as follows: 1) TBM pilotheading method is not suitable for singletube tunnels located in soft, weak and fractured strata; 2) Instead of other construction galleries, TBM pilotheading method may be adopted for singletube tunnels. 3) Twin TBM pilotheading method is suitable for twintube extralong tunnels, which has advantages in terms of construction schedule, cost and coping with unfavorable geological conditions; 4) TBM pilotheading method is suitable for the construction of tunnels in Sichuan and Chongqing area. Finally, the application of TBM pilotheading method is prospected.