Lateral Boundary Effect in Centrifuge Tests for Spudcan Penetration in Uniform Clay

Abstract

The effect of the centrifuge strongbox boundary on the penetration resistance of a spudcan foundation in uniform clay has been studied using Large Deformation FE analysis. Both smooth and rough strongbox boundaries were considered with various strongbox sizes. The spudcan penetration resistance and soil flow mechanisms were analysed. It was observed that, when the strongbox size was reduced, the spudcan penetration resistance was decreased for a smooth boundary and increased for a rough boundary. The depth of cavity formed above the spudcan during its penetration, in most cases, was determined by the soil flow around mechanism without cavity wall failure. However, cavity wall failure could be initiated when a smooth strongbox boundary was very close to the spudcan. The strongbox boundary effect on the spudcan penetration resistance can be avoided when the distance of the strongbox boundary to the spudcan centre is larger than 1.5 times of spudcan diameter for a rough boundary; or 2 times of spudcan diameter for a smooth boundary.