Abstract:

In the BafenshanDrainage Reconstruction of Wuhan JiangxiaClear River Discharge Project, due to the narrow and small space of the launch shaft of shield tunnel, shield tunneling equipment assembly and launch tunneling can not be carried on by adopting conventional launching construction technology. In order to solve such problem, the engineering hydrogeology, launchshaft and tunnel structure are analyzed and studied. Some parts of the shield such as subsidiary facilities, temporary ringand slag discharging systemare modified. Temporary propulsion devices are added.Finally a kind of separate construction technology with the combination of partial assembly and partial propulsion is proposed.The construction technique can solve the problems of limited launching space, shield assembly, launching and equipment parts vertical transportation, personal access and so on.The launching process is safe and smooth and the ground settlement meets the requirements, indicating that the effect of the separate launching technology is good.

Key words: narrow and small space, earth pressure balance shield, shield tunnel, modify, separate launching