On the seismic response of a propped r.c. diaphragm wall in a saturated clay

A series of nonlinear dynamic FE simulations have been performed to investigate the seismic performance of a flexible propped retaining wall in a saturated clay. The simulations have been carried out considering different acceleration time histories at the bedrock and two different inelastic soil models: the classical elastoplastic Modified Cam Clay model and the advanced hypoplastic model for clays proposed by Masin (Int J Numer Anal Methods Geomech 29:311-336, 2005) equipped with the intergranular strains extension. The results of the simulations highlight the major role played by the choice of the constitutive model for the soil on the predicted seismic response, in terms of predicted wall displacements and structural loads. In particular, the results show that a key role is played by the model ability to correctly reproduce soil dilatancy as a function of the current stress state and loading history. This has a major impact on the inelastic volumetric deformations accumulated during the undrained seismic shearing and on the development of excess pore water pressures around the excavations.