METHOD OF STABILIZING WORKING FACE OF MUDDY EATER TYPE SHIELD EXCAVATION

摘要

PROBLEM TO BE SOLVED: To prevent mud from escaping from the working face through clogging in the recess of the working face by blending a water absorption polymeric material into muddy water in a working face stabilization method for stabilizing the working face with muddy water pressure. ;SOLUTION: On the way a mud feeding pipe 44 in a tunnel 36, there is provided each thickener tank 50 and clogging material tank 52 of containing a water absorption polymer material, and by performing viscosity control on the way of the mud feeding pipe 44, control is carried out stably for the working face. After determining the particle size of salt resistance water absorption polymeric material used for a clogging material and dispersing once the water absorption polymer material in an organic solvent to be a suspension liquid, it is mixed into muddy water. Such water absorption polymeric material improved in its salt resistance is employed as the clogging material, so that a clogging function can be exhibited suitably without lowering the magnification of water absorption for a long period of time even in muddy water with relatively high salt density.;COPYRIGHT: (C)1997,JPO