METHOD OF CONSOLIDATION GROUND IMPROVEMENT BY UTILIZING SIPHON EFFECT OF GAS-LIQUID TWO-PHASE DOWNFLOW

Abstract

  The vacuum consolidation method, which uses vacuum pressure generated by vacuum pumps, has recently been drawing attention as a remarkable method of consolidation ground improvement. The method has the advantages to enable rapid construction of embankment avoiding shear failure of foundation, and bulk attenuation of clayey soil in disposal sites, etc. In this study, a new method is proposed to utilize vacuum pressure by the siphon effect in a water-filled vertical pipe for the vacuum consolidation method. Especially, gas-liquid two phase downflow is realized within a vertical drainpipe in the condition of intensive negative pressure that dissolved oxygen is evaporated. The effects of proposed method for ground improvement are verified by conducting laboratory and field experiments.