ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, D.C. Charmpis, N.D. Lagaros, Y. Tsompanakis (eds.) Rethymno, Crete, Greece, 13–16 June 2007 SEISMIC HAZARD ASSESSMENT OF HISTORIC RESIDENTIAL BUILDINGS UTILIZING IN-SITU MEASUREMENTS Günther Achs 1 , Helmut Wenzel 1 , and Christoph Adam 2 1 VCE Vienna Consulting Engineers Hadikgasse 60, 1140 Vienna, Austria e-mail: {achs,wenzel}@vce.at 2 University of Innsbruck, Faculty of Civil Engineering Technikerstraße 13, 6020 Innsbruck, Austria e-mail: christoph.adam@uibk.ac.at Keywords: Combined Experimental - Numerical Analysis, Finite Element Model Update Procedure, System Identification. Abstract. In this paper a simple and economically competitive procedure for the seismic as- sessment of historic buildings is proposed. The approach is based on a combination of ex- perimental investigation with successive numerical analysis. The dynamic parameters of the building such as natural frequencies and mode shapes are determined from in-situ measure- ments. A simplified mechanical model, where the mass is lumped to the story levels, repre- sents the building. The distributed stiffness of the model is identified by a finite element modal update procedure utilizing the experimentally determined characteristics. A pushover analysis yields the capacity curve, and a capacity spectrum is utilized to determine the performance point. Consequently, the seismic vulnerability of the original object can be evaluated. Struc- tural changes (mass, stiffness) of projected reconstructions are considered in a modification of the mechanical model, and seismic assessment is performed as for the original structure.