VACUUM CONSOLIDATION DRAIN METHOD, AND MANDREL FOR SEALING LAYER TO BE BACKFILLED

摘要

PROBLEM TO BE SOLVED: To provide a vacuum consolidation drain method capable of fully performing sealing work for a sealing layer even though a bore hole is formed in the sealing layer after pulling out a mandrel. SOLUTION: A draining member 2 with a water drain hose connected to its top end is poured vertically in a weak stratum 9 by using a backfilling mandrel 14 for the sealing layer. Thereafter, the mandrel 14 for backfilling the sealing layer is pulled out. A mandrel pulling bore hole 13 formed in the sealing layer 10 by the mandrel 14 for backfilling the sealing layer is filled up with a raw material 18 having air tightness such as mud or mud water discharged from a discharge hole 16 of the backfilling mandrel 14 for the sealing layer. COPYRIGHT: (C)2008,JPO&INPIT