Abstract:

Regardless of MRT tunnel, subway tunnel or sewer project, the present shield tunneling method has been the mainstream in the soil type ground condition. Although the cost of shield tunneling is expensive, the method is still used in urban tunnel construction by the most contractors because of its minimum impact on the urban living. Generally speaking, shield tunneling is quick if obstacles are not encountered. For slight stuck situation, shield has to be stopped to remove obstacles and for the worest situation, the shield has to be repaired and the schedule may be delayed and the tunnel route may be changed. A case of shield machine encountering obstacles is given in this paper, the construction evaluation of shield, the process from shield inspection to restoration and the influence of tunneling on surrounding enviornment are presented in detail. This article may provide reference for similar projects construction in the future.

Key words: shield machine, shieldbored tunnel, underground obstacle, ground improvement, ground freezing method, repair work