Mapping soil effects in Barcelona, Spain, through an integrated GIS environment

Maps of soil response for the city of Barcelona have been for the first tim e obtained through a GIS environment that integrates the different procedur es for soil response estimation within a single tool. These maps constitute part of the results of the local scale application of the computer prototy pe for seismic risk assessment that was developed within the European proje ct SERGISAI. The approach involves: collection of available data relevant t o local geology, implementation of geotechnical models, estimation of the r eference seismic action, generation of synthetic strong-motion time histori es, and soil response calculation through 1D analytical method. The resulti ng predictive hazard maps of predominant period and amplification ratio del ineate potential variations on ground shaking and constitute a first approx imation towards an integrated approach to Barcelona urban area microzonatio n. Analysis of the observed differences, when comparing the analytical resu lts in this study with previous empirical studies, provides a useful feedba ck to establish site dependence suitability and reliability of methods, to extract information on at-present inaccessible parameters needed for the ch aracterisation of physical properties of soil, and also to delimit those ar eas where further in-depth survey research is needed for a proper seismic h azard assessment. (C) 2000 Elsevier Science Ltd. All rights reserved.