Site Effects Evaluation in Monumental and Civil Residence Buildings in the Urban Area of Catania

Aim of present paper is to evaluate the local seismic response in sites located in the urban area of Catania, where either monumental buildings or edifice for civil residence are erected. Both reinforced concrete and masonry buildings were taken into account, as well as several churches. For each building the natural frequency and the site response was evaluated using ambient noise measurements and analysing the time series through spectral ratio H/V technique. Tests were performed estimating to what extent the presence of a building may affect the microtremor measurements in the evaluation of seismic response linked to local lithological conditions. The oscillations transmitted to the ground by the buildings don't seem however to significantly influence the evaluation of the local seismic response. The site response was also evaluated using theoretical models. Moreover, displacement, velocity and acceleration parameters in the free field of each peculiar site were determined using a 1-D non-linear code. A good agreement between the experimental results and the modelling was observed.