Non linear soil-structure interaction in building affected by earthquake

This report presents the nonlinear calibration of a monitored structure (School Pietro Capuzzi located in Visso, province of Macerata), considering the phenomenon of the ground-structure interaction. In order to estimate the evolution of the model parameters over time, a time-frequency distribution of the records was used for the identification. The fundamental frequency of the ground is available by seismic test at single station HVSR in free field conditions, with which it was possible to reconstruct the stratigraphic profile of the ground until reaching the Bedrock at 40 m. For the process of deconvolution and the search for the seismic input signal, models by literature have been adopted for the stratigraphy, with particular reference to the formulations proposed by Vucetic & Dobry, Seed & Idriss and Rollins. Two different models were considered for the dynamic behaviour: The rate-independent Bouc-Wen for the structure and a rate-dependent model (a modified version of the rate-indipendent Davidenkov model) for the soil. As regards the masses of the structure that come into play in the analysis, they have been estimated with the use of finite elements (FE) models.