Realistic modeling of seismic input in urban areas: A UNESCO-IUGS-IGCP project

The estimation of realistic seismic input can be obtained from the computat ion of a wide set of time histories and spectral information, corresponding to possible seismotectonic scenarios for different source and structural m odels. Such a data set can be very constructively used by civil engineers i n the design of new seismo-resistant structures and in the reinforcement of the existing built environment, therefore supplying a particularly powerfu l tool to the prevention efforts of Civil Defense. The availability of real istic numerical simulations enables us to estimate the amplification effect s in complex geological structures exploiting the available geotechnical, l ithological, geophysical parameters, topography of the medium, tectonic, hi storical, paleoseismological data, and seismotectonic models. The realistic modeling of the ground motion is a very important source of knowledge for the preparation of groundshaking scenarios which represent a valid and econ omical tool in seismic microzonation.