Dynamic soil-structure interaction by experimental and numerical modeling

The present paper deals with a coupled dynamic soil-foundation-superstructure interaction (DSSI), investigated by means of a 1-g shaking table test, involving a 5.0x1.0x0.9 m sand deposit and a 1.30x0.95x1.30 m steel frame. The system is subjected to sine-dwell horizontal acceleration time-histories. The system is monitored by numerous accelerometers and displacement transducers. The shaking table test is simulated through numerical FEM analyses, considering for the soil both a linear viscoelastic (LE) constitutive model, still widely used in professional practice, and a sophisticate viscoelasto-plastic with isotropic and kinematic hardening (NL) constitutive model, definitively more appropriate for dynamic analyses. The dynamic response of the system is analysed in the time and frequency domains. The main goals of the paper are: i) to investigate the effects of soil non-linearity and DSSI on soil and structures, that are useful for practical engineering design purposes, in terms of accelerations and displacements in the soil and on the structure; ii) to highlight some crucial aspects of numerical modelling in reproducing shaking table tests on DSSI. The paper is part of a research activity, consisting of numerous tests and related numerical simulations firstly on dynamic soil-foundation interaction (DSFI) and secondly on DSSI