Stiffness Nonlinearities of SCP-inserted Clay Specimens with Various Replacement Ratios in Triaxial Compression Tests

Abstract

The sand compaction pile (SCP) method is one of the widely used ground improvement techniques for the embankment constructed on the soft clay. The behavior of SCP-improved ground becomes very complex due to the differences in the stiffness and strength of the SCP and the original soft ground. Since the behavior of the SCP-improved ground greatly affects the performance of the embankment, it is crucial to understand the mechanical behavior of the SCP-improved ground under the field conditions. Thus, in this study, triaxial compression tests after K 0 consolidation are performed on the SCP-inserted clay specimens to characterize the stiffness nonlinearity for the SCP-improved ground. Based on the stress-strain behaviors of SCP-inserted clay specimens with different replacement ratios, the secant Young's modulus is obtained with strain level. The initial stiffness value and stiffness degradation patterns are greatly affected by the replacement ratio showing similar trends with those of the major component of the SCP-inserted clay specimen.