Evaluation of FEMA440 Equivalent Nonlinear Static Seismic Analysis for Irregular Steel Moment Resisting Frames

Abstract eng:
It is well established that for seismic evaluation, design, and retrofitting of building structures, a simplified design-oriented modeling procedure is more practical. One of well-established procedures is the equivalent nonlinear static procedure summarized in FEMA356 based on nonlinear static pushover analysis using the target displacement predicted by the Coefficient Method (CM). CM utilizes a displacement modification procedure in which several empirically derived factors are used to modify the response of a single-degree-of freedom model of the structure assuming that it remains elastic. FEMA440 has suggested some recommendations for improving the performance of CM leading to a Modified Coefficient Method (MCM). This paper presents a detailed investigation on performance of FEMA440 MCM for estimating frame maximum roof displacement, base shear, and median story drifts of steel moment resisting frames with irregularities in elevation. Results of nonlinear dynamic analyses of 22 irregular frames subjected to a family of 14 ground motions and nonlinear equivalent static analyses of all frames up to the target roof displacement computed by MCM are compared to evaluate the accuracy and conservatism of FEMA440 MCM.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket