Bearing capacity of clay bed improved by sand compaction piles under caisson loading

Abstract

In the present centrifuge study, model Sand Compaction Piles (SCPs) were installed in-flight in a clay bed. The improved ground was loaded to failure by in-filling a model Perspex caisson in-flight. A method of estimating the increase undrained shear strength (cu) due to the SCP installation process was proposed. The conventional bearing capacity analysis and the proposed modified analysis using the increased cu were compared with the centrifuge test results. It was found that the modified analyses yielded a higher calculated safety factor. The implications are that some savings in terms of sand can be achieved if design is performed utilizing the increased cu.