盖挖逆作法在城市隧道中的应用

近几年来,一种"盖挖逆作法"施工新技术正被逐渐运用并趋于成熟。该工法适用于多层地下结构工程的施工,在对工程有特殊要求,或用传统方法施工满足不了要求而又十分不经济的情况下采用。海河隧道靠近海河处最大基坑开挖深度达到26.6 m,为滨海新区第一深基坑,隧道主体结构位于软土地基上,采用盖挖逆作法进行基坑开挖,有效地降低了风险。利用大型有限元软件ABAQUS全过程模拟海河隧道岸边段深基坑开挖过程,揭示了支护结构的受力及变形情况。

Application of Cover-Excavation Reverse Construction Method in Urban Tunnel

In recent years,a new construction technology of cover-excavation reverse construction method is gradually been using and is becoming ripe.This construction method is suitably used for the construction of the multi-layer underground structure projects,and used under the conditions of the projects with the special requirements or the tradition construction methods not able to satisfy the requirements and also not very economized.The excavation depth of the largest foundation pit for Haihe Tunnel closing to Haihe River is 26.6 m.It is the first deep pit in Binhai New Area.The main structure of tunnel is located on the soft soil subgrade.The use of cover-excavation reverse construction method for the excavation of the pit can effectively reduce the risk.The large finite element software ABAQUS is used to simulate the whole process of the deep pit excavation at the bank section of Haihe Tunnel,which opens out the stress and deformation of the supporting structure.