Seismic Vulnerability Evaluation of Existing Buildings

A study of building seismic vulnerability evaluation methods in the U.S. and Japan lead to a constructive critique of the FEMA-178. Research is formulated to extend FEMA-178 so that types of construction which have not yet experienced damaging earthquakes may be reliably evaluated. An element-level analytical model accurately simulating the critical response and failure mechanisms of the soil-foundation-structure in its current state emerges as a key. Developing such a model may prove difficult in case a facility has unusual and/or irregular attributes as well as damage and/or deterioration. Researchers efforts to construct and experimentally identify a 3D analytical model of a 27-story RC flat-plate building with closed thin-walled core systems are described. Forced-excitation modal testing is explored and is shown to be a reliable tool. It is exemplified that structural identification as well as other nondestructive evaluation tools may become essential for reliably evaluating seismic vulnerability of construction which have not yet revealed all of their “weak-links”.