CONTROL METHOD OF FREEZING OF GROUND IN IN-SITE GROUND FREEZING SAMPLING METHOD

摘要

PROBLEM TO BE SOLVED: To shorten a freezing time by a method wherein an auxiliary freezing means is juxtaposed together with a freezing pipe up to a required depth section from the lower-end site of a guide pipe to a lower section, a refrigerant is circulated to the freezing pipe and the freezing of the ground is promoted, and the auxiliary freezing means is worked and the freezing of the ground in a region just under the guide pipe is accelerated in a duplex manner. ;SOLUTION: An auxiliary freezing means 11 is juxtaposed together with a freezing pipe 2 to a required depth section from the lower-end site of the guide pipe 1 installed to the ground surface section of an in-site ground to a lower section, concretely a section within a range of depth H₂, in which the progress of freezing is delayed. A refrigerant is circulated through the freezing pipe 2 to promote the freezing of the ground, and the auxiliary freezing means 11 is worked and the freezing of the ground in a region just under the guide pipe 1 is accelerated in a duplex manner. Accordingly, the freezing of the region just under the guide pipe is promoted comparatively quickly, and a freezing time can be shortened.;COPYRIGHT: (C)1997,JPO