ANALYSIS OF GEOSYNTHETIC REINFORCED STONE COLUMNS IN SOFT CLAY

摘要

The paper presents the findings of a series of numerical studies on the behaviour of geosynthetic encased stone columns in very soft clay deposits and surcharged by embankment type loading. Observed settlement of a trial embankment built on very soft clay strengthened with stone columns indicated that the stone columns were not adequately effective in reducing settlement. Earlier work showed that the very softy clay could not provide adequate confining stress to the stones. For this reason, an alternative concept utilizing geosynthetic encasement was examined numerically. As the primary issue is the development of settlement with time after the completion of stone column installation, a fully coupled analysis was performed. To reduce the computational effort, a unit cell idealization was adopted. This study showed that the use of geosynthetic encasement has the potential of significantly enhancing the effectiveness of stone colunms in very soft clay and the simplified analysis presented in earlier work is valid.