Shaft pithead temporary wall null for non excavation propulsion

摘要

PROBLEM TO BE SOLVED: To finely crush a temporary wall with a shield machine and easily construct a starting/arrival shaft by arranging the temporary wall buried with glass beads in the surface to form a finely crushing layer on a shaft mouth.;SOLUTION: A temporary wall 1 is formed with a finely crushing layer 1a made of resin mortar and buried with many glass beads 2 and a strength securing layer 1b with the required thickness and buried with no glass bead 2, the temporary wall 1 is fitted to the shaft mouth of a starting/arrival shaft, and a water stop device is fitted on the inside. When a shield machine is advanced from the inside of the shaft into contact with the temporary wall 1 through the water stop device, the temporary wall 1 is deflected and finely crushed by means of cracks generated from the glass beads 2, and no problem occurs on the excavation of the shield machine. In the case of an arrival shaft, the shield machine first crushes the temporary wall 1 and enters the shaft through the water stop device. Many grooves may be crossingly formed on the surface of the temporary wall 1 in place of the glass beads 2. The starting/ arrival shaft can be easily constructed.;COPYRIGHT: (C)2000,JPO