Behaviour of pile groups in liquefying soil

This paper presents a simplified method of analysis for pile groups founded in liquefying soil. The method involves two main steps. First an effective stress based ground response analysis is carried out to obtain the maximum ground displacements along the pile and the degraded soil modulus over the depth of soil deposit. Next a dynamic analysis is carried out for a single pile in the group assuming that each pile in the group behaves in the same way during the earthquake loading. The method has been verified using centrifuge data, where soil liquefaction has been observed in laterally spreading ground. It is demonstrated that the new method gives good estimate of pile behaviour, despite its relative simplicity.