Seismic zonation of Barcelona based on numerical simulation of site effects

Seismic responses of different sites of Barcelona have been investigated th rough numerical modelling. Geological maps and geotechnical data available from drillings for buildings and infrastructures have been used to determin e the dynamical properties of the soils through different correlations betw een standard geotechnical data and dynamical parameters obtained in other r egions. An estimation of the depth of the Palaeozoic basement has been obta ined through an inversion of a detailed gravity survey. A I-D equivalent li near method has been used to compute complete transfer functions and other spectral responses, such as PSA and PSV for various damping values, with th e purpose of classifying zones with similar behaviour. Given the uncertaint ies associated, with the input data, a Montecarlo's simulation process has been carried out. Four zones, characterized by their corresponding transfer function and by PGA amplifications, are proposed. The numerical results ar e compared with those previously obtained through microtremor measurements, showing that predominant periods derived from Nakamura's technique should be taken carefully.