The effect of soil–foundation–structure interaction on the wind-induced response of tall buildings

• The work contributes in studying the soil–foundation–structure–interaction effects.
• Tall buildings founded on rigid rafts and subjected to wind loading are considered.
• Two different approaches are adopted: a (pseudo-)elastic model and a macroelement.
• The macroelement accounts for the irreversible behavior of the soil–foundation system.
• The forces and moments distribution predicted by the two models are very different.

The aim of this work is to provide a contribution towards the qualitative and quantitative assessment of soil–foundation–structure interaction effects on the dynamic response of tall buildings founded on relatively rigid rafts, and subjected to wind loading. The mechanical response of the soil–foundation system is modeled using two different approaches: in the first, the (visco)elastic system response is defined in terms of impedance coefficients; in the second, an inelastic, 6 DOF macroelement recently proposed for shallow foundations on coarse-grained soils is adopted. The macroelement approach allows to account for the non-linear and irreversible behavior of the soil–foundation system, and to consider the experimentally observed coupling between the different degrees of freedom in the inelastic regime. The results of a series of numerical simulations highlight the importance of considering SFSI effects in the analysis, and allow to identify the effects of the different constitutive assumptions made for the soil–foundation system. In particular, it is found that the permanent displacements and rotations accumulated at the foundation level in the inelastic simulations can give rise to significant permanent displacements at the building top. Moreover, significant differences are observed on the predicted forces and moments distribution at the building base for the two SFSI approaches considered.