Numerical analysis of deformation behaviour of quay walls under earthquake loading

In the last 50 years, there have been many incidences of failure of gravity quay walls. These failures are often associated with significant deformation of liquefiable soil deposits. Gravity quay wall failures have stimulated great progress in the development of deformation-based design methods for geotechnical structures. In this paper, the effective-stress analysis method has been used in conjunction with a generalised elasto-plasticity constitutive model implemented into a finite element procedure. Various monotonic and cyclic triaxial paths are simulated in order to demonstrate the capabilities of the constitutive model. The FEM is validated by back analysis of a typical Port Island PC1 caisson type quay wall, which was damaged during the 1995 Hyogoken-Nanbu earthquake. The numerical results are compared with the observed data obtained consisting of seaward displacement, settlement and tilting. In addition, both the influence of permeability, on the generation of pore water pressure and the influence of the relative density of the backfill and foundation layers, on the residual deformation of gravity quay walls are investigated.