Ricerc@Sapienza

Predicting the seismic site effects in complex real case histories is a non-trivial scientific and technical task. In fact, it requires the overall geometry of the problem (i.e. surface and underground) to be properly described and combined to adequate soil models, accounting for the peculiar aspects of the dynamic soil behaviour. These latter should include the dependency of the initial stiffness on the stress state and its non-linear evolution with strain amplitude, together with the corresponding one of the damping ratio.

This paper critically examines the numerical predictions of the seismic site response of both ideal and real cases as obtained by means of mono- and multi-dimensional Finite Element (FE) approaches. Ideal case-studies are first considered, aiming at validating the adopted numerical approach against existing analytical or simple numerical solutions. Then a three dimensional model of the Bovino urban area, located in southern Italy, was generated taking into account the real site conditions.

This paper describes a numerical approach for the analysis of the seismic ground response and the dynamic soil-structure interaction accounting for the three components of an earthquake motion. The investigation was performed with reference to the case-history of Lotung (Tai-wan), where the seismic response of a nuclear power plant model as well as that of its founda-tion soil were measured during several earthquakes occurred at the site.