Underwater tunnel construction machine - has leading side of foremost tunnel section sealed to prevent entry of water

摘要

After the foremost tunnel section (5) has left the starting shaft, a diving bell (8, 21) with a connected sluice (13) is placed in front of this tunnel section and fixed to it. Within the working chamber of the bell precise footings or earthworks are formed in stages for the advance and support of successive tunnel sections (5, 6). Within the bell a sliding surface (17) is placed on the footings and is made of e.g. bentonite. The bell itself is attached to the foremost tunnel section and can move vertically relative to it. Preferably the foremost tunnel section itself forms a sluice for the entry of the diving bell.