IMPROVING METHOD AND DEVICE FOR GROUND UNDER EXISTING STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide a method and a device effective as a countermeasure against liquefaction for maintaining functions of an existing structure of which functions need to be constantly maintained. SOLUTION: A small diameter excavation hole is formed in a runway 2 on the ground 1 of an airfield (airport) where a compaction grouting Denver system is applied by means of an on-vehicle type boring machine 14. Next, a solidified and stacked body 41 of soil mortar of no fluidity and low slump is continuously fed under pressure to be laminated by an on-vehicle special pressure-feeding pump. Peripheral ground is compacted and hardened to be compressed and tightened for reducing gaps in the ground 1 for improving strength and rigidity. Generation of irregularities or liquefaction in the runway 2 by an earthquake such as a severe earthquake to cause trouble in aviation security facilities is thus prevented to achieve functions of the security facilities.