REASONABLE CONSTRUCTION MANAGEMENT IN FILL LOADING WITH VACUUM CONSOLIDATION METHOD BASED ON FEM ANALYSES

摘要

Vacuum consolidation method (VCM) is one of the recent methods for the improvement of soft ground. This method can forcibly drain pore water, and increase ground strength by loading of the vacuum pressure. A fill loading with vacuum consolidation method (FLVCM) is considered to be able to control lateral flow and upheaval of surrounding area during the rapid fill construction. However, the behavior of this combination on the ground deformation is not fully clarified on FLVCM, fill design and site management is depending on the experienced technique. In this study, numerical simulation has been carried out by finite element method (FEM) for the quantitative evaluation of the deformation suppression effect of FLVCM on the soft grounds of ariake clay, Japan. The utility of FLVCM was confirmed from comparison with the observed and the analytical ground deformation. In addition, the numerical simulation have been carried out under the various conditions of vacuum pre- and post-loading pressures and fill speeds, and it is suggested that the reasonable construction management index can be easily obtained by the site measurement of deformation.