MECHANISCHE SCHILD-VOORTDRIJFWERKWIJZE MET GEBRUIKMAKING VAN EEN SCHUIMMIDDEL.

摘要

In a mechanical shield driving method, a solution containing a foaming agent diluted with water and stored in a tank (11) is agitated by a foam generator (13) together with air from a compressor (14) to thereby generate foam. The foam thus produced is fed via a pipe (15, 16) to at least one of an excavation face and an earth pressure chamber (7) of the mechanical shield machine. The frictional resistance between the cutter head (2) and the excavation face is reduced by the lubricating action of the foam. The excavated muck brought into the earth pressure chamber (7) and the foam are mixed together to form excavated muck containing air bubbles. The mixture has increased fluidity and lowered permeability. The excavation at the cutter face takes place while resisting the earth pressure and ground-water pressure with the excavated muck containing the air bubbles, and at the same time the excavated muck is discharged from the earth pressure chamber by means of a screw conveyor (8).