Punch-through of spudcan foundation in sand overlying clay

Abstract

Spudcan installation in sand overlying clay is subjected to potential punch-through hazard. Punch-through failure occurs when the applied load exceeds the maximum bearing resistance of the layered soil causing the spudcan to plunge into the underlying clay. To provide a better understanding of the spudcan bearing resistance in sand overlying clay, centrifuge modeling was undertaken to investigate the development of the bearing failure mechanism and bearing resistance-depth profile. The former investigation demonstrated that the failure mechanism changes with spudcan penetration; whereas the latter study established that the spudcan bearing resistance is governed mainly by the bearing pressure ratio between the two layers and the thickness of the sand layer relative to the spudcan diameter. Identifying the limitation of the existing design methods, a novel design framework is proposed to enhance the prediction of the spudcan bearing resistance-depth profile in the layered soil. The proposed framework is validated using experimental results.