In under the artesian of the ground water soil improvement construction method and the packer device null

摘要

PURPOSE: To enable execution and, at the same time, to make it possible to control properly sludge discharge even in pressurized ground water by providing the formation level in a vertical shaft, and controlling the pressure of sludge discharge by means of a pressure controller. ;CONSTITUTION: The ground is excavated to form the formation level 3 in a vertical shaft, the depth from the formation level to the improvement ground is shallowed, and boring work can be easily executed. After that, the pressure of sludge discharge occurring with the cutting by a jet water is controlled, the sludge is discharged while controlling sludge discharge, and grout can be accurately filled into the improvement ground 1 to which high water pressure is applied. In addition, two up and crown stages of packer rings are provided, and a jet of ground water, etc. from the outlet of an injection pipe of the formation level on a position lower than the ground water level is prevented by means of a packer device branching a sludge withrawal pipe provided with a pressure controller 12. At the same time, sludge can be discharged while controlling properly sludge discharge.;COPYRIGHT: (C)1993,JPO&Japio