大断面软岩铁路隧道贯通控制要点

Key Points for the Breaking-through of Large-profile Railway Tunnels in Soft Rocks

隧道贯通前后施工中涉及到贯通误差的预计及调整,以及合理的施工方案、科学的施工组织等问题;另外隧道贯通段受力结构复杂,尤其是软弱围岩,经常在贯通后出现围岩收敛过大、初期支护变形开裂等现象,若处理不当,容易造成塌方。文章结合兰渝铁路第I合同段隧道群的施工,介绍了隧道贯通前后的施工控制要点。

Error prediction and adjustment as well as reasonable construction option and organization will be concerned with before and after tunnel breaking through.In addition,it is very complex for the structure at the tunnel breaking-through section.Especially in soft rocks,it is very often to have large convergences and deformations and cracking in primary support before and after the breaking-through of tunnel,liable to result in collapse.The key points of construction before and after the tunnel breaking-through are presented in the paper by taking the construction of tunnel group at Lot I of Lanzhou-Chongqing railway as the background.