Abstract:

Prior to reaching the arrival shaft, Qianwan subsea shielddriven tunnel in Shenzhen has a 358mlong portion situated in hard rocks which have an average uniaxial compressive strength of 98MPa and a maximum uniaxial compressive strength of 108MPa. Due to the fact that there would be great difficulities for the mentioned tunnel portion to be bored by the shield machine and in order to reduce the construction risks and to develop the supporting technology for the long distance advancing of slurry shield machine in hard rocks, researches are made. As a result, it is determined that the mentioned tunnel portion is excavaed by means of drill+blast method, which is followed by primary reinforcement of the tunnel portion, advancing of the shield machine without load through the tunnel portion together with simultaneous segment lining and backfill grouting. In the end, great success is achieved for the advancing of the shield machine through the completed drill+blast tunnel portion. The article presents the advancing technology of shield machine through completed drill+blast tunnel portion.

Key words: shield machine mined tunnel  , advance