Time: May 3, 2017 at 4 pm Place: University of Natural Resources and Life Sciences (BOKU), Seminar room 03, Guttenberghaus (GUTH-SR 03), Feistmantelstraße 4, 1180 Vienna
Soil Structure Interaction (SSI) under Dynamic Loading Conditions
In engineering practice, buildings are often designed considering the base of the structure as fixed to the ground, thus neglecting Soil–Structure Interaction (SSI) effects. Although this assumption can be considered reasonable for low–rise buildings on relatively stiff soils, the effect of SSI becomes prominent for heavy structures resting on relatively soft soils. Soil deformability may lead to an increased overall deformation of the system, with the accumulation of significant irreversible displacements, and to a different distribution of the internal forces, with a net reduction in the structural demand.
The most commonly used method to account for SSI effects is modeling the soil–foundation system with a series of (visco)elastic elements whose stiffness and damping coefficients are defined through equivalent springs and dashpots.
A number of alternative, more effective approaches have been extensively developed during recent years. Among these, the macroelement approach is particularly worth mentioning. It consists in lumping the response of the foundation–soil system into a single computational node, using a single inelastic constitutive equation written in terms of generalized loads and displacements. This allows to effectively reproducing the nonlinear, irreversible and hysteretic response of shallow foundations subject to cyclic/dynamic loading conditions.
Recent formulations, developed in the framework of elastoplasticity and hypoplasticity, include the possibility for the macroelement of: i) reproducing the full–scale behavior of the soil-foundation system starting from small–scale tests, ii) simulating the foundation response under six-dimensional loading paths; iii) modeling the shake-down effects that occur when a structure is subject to a large number of cyclic loads. Applications to real case studies will be presented to show the capability of the approach.
Biography of Prof. Salciarini
Diana Salciarini is an Assistant Professor of Geotechnics at the Department of Civil and Environmental Engineering of the University of Perugia.
She works in the fields of theoretical and computational soil mechanics and modeling of fully coupled multi-physical systems, with a special emphasis on geomechanical applications. The objective of her research is to advance the understanding on multiphase materials under extreme conditions and enhance predictive capabilities for related engineering applications, including but not limited to: rainfall-induced landslides, soil-structure-interaction effects under dynamic/cyclic loading conditions, hydro-thermo-mechanical behavior of energy foundations.
Her research includes: formulation and implementation of advanced models based on the macroelement approach; combined deterministic-stochastic method for natural hazard predictions; and development of finite element analyses for unsaturated THM engineering problems.