PERFORMANCE OF AN SDCM COLUMN-SUPPORTED EMBANKMENT
Keywords:
Deep mixing, embankment, SDCM column, simulation, soil stabilizationAbstract
The stiffened deep cement mixing (SDCM) column uses a precast concrete core inserted at the center of a DCM column. This research presents the full-scale behavior of a test embankment built on a soft clay deposit improved by using both DCM and SDCM columns in Bangkok, Thailand. A 0.22 m square and 6 m long concrete pile was selected as a stiff core to create the SDCM column for this study. Both SDCM and DCM columns were subjected to axial compression and lateral load tests to determine the vertical and lateral loads, respectively. A three-dimension finite element analysis was performed to determine the axial load and bending moment in the DCM and SDCM columns. In addition, a stability analysis was also conducted to calculate the factor of safety against the slope failure. The major findings show that the lateral ultimate bearing capacity of the SDCM column and the displacement of improved ground with the column under the embankment loading can be improved by factors of 13 and 1.8, respectively, compared to the DCM column.
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