Numerical Simulations and Parametric Study of SDCM and DCM Piles under Full Scale Axial and Lateral Loads

A new kind of reinforced Deep Cement Mixing (DCM) pile namely; Stiffened Deep Cement Mixing (SDCM) pile is introduced to mitigate the problems due to low flexural resistance, quality control problem and unexpected failure of the DCM pile. The SDCM pile consists of a DCM pile reinforced with concrete core pile. Previously, a full scale pile load test and a full scale embankment loading test were successfully conducted in the field. To continue the study on the behavior of SDCM and DCM piles, the 3D finite element simulations using Plaxis 3D Foundation Software Version 1.6 were conducted in this study. The simulations of full scale pile load test consisted of two categories of testing which are the axial compression andthe lateral loading. For DCM C-1 and C-2 piles simulations were conducted for the clay-cement cohesion, C_DCM, as 300 kPa and 200 kPa as well as the clay-cement modulus, E_DCM, as 60,000 kPa and 40,000 kPa. For the SDCM piles, the simulation results show that increasing length ratio, L_core/L_DCM, increased the bearing capacity with small effect from the sectional area ratio, A_core/A_DCM, for the axial compression loading. On the other hand, increasing the sectional area ratio, A_core/A_DCM, significantly influenced the ultimate lateral resistance while the length ratio, L_core/L_DCM, has little effect on the ultimate lateral load capacity when the length of concrete core pile is longer than 4.0 m.