Abstract
The present study investigated and elucidated the liquefaction characteristics of sand-clay layered ground under sequenced earthquake motions by performing a series of shaking table tests. In particular, we evaluated the influence of aftershoks on the liquefaction. Futhermore, we examined the effects of two different compaction methods, namely, sand compaction pile and compaction grouting, on the liquefaction in sand-clay layered ground. The resuts demonstrate that the CPG-induced sand densification and increase in the horizontal effective stress contributed to surpressing liquefaction. By contrast, the application of the SCP is found to work effectively in light of the three distinct mechanisms involving densification, stress enhancement, and partial drainage through the sand pile penetrating the clay layer. These findings are important for the rational liquefaction assessment and its countermeasures of sand-clay layered ground.
