Validity Of Static Procedures In Performance-Based Seismic Design

The introduction of a performance-based design philosophy in FEMA-273 (1997) for seismic rehabilitation of buildings marks a significant departure from traditional seismic design. Two types of analysis methods for estimating seismic demands in building structures, which can be broadly classified as linear and nonlinear procedures, are outlined in the document. This implies that an engineer can make reliable estimates of deformation demands using either one of these analysis methods. This paper is an attempt to confirm or demystify the validity of linear and nonlinear static procedures in arriving at reasonable estimates of deformation demands in relatively regular building structures. Two structures: an existing 6-story steel building and a 7-story reinforced concrete building are used as case studies to evaluate the different analytical procedures. It is concluded that commonly-utilized static procedures, including those recommended in FEMA-273, are generally inadequate and substantially enhanced procedures are needed if static methods are to be successfully used in performance-based seismic evaluation of structures. Copyright 2004 ASCE