EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS Earthquake Engng Struct. Dyn. 2005; 34:1719–1736 Published online 1 June 2005 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/eqe.506 Seismic demand sensitivity of reinforced concrete shear-wall building using FOSM method Tae-Hyung Lee § and Khalid M. Mosalam ∗; †; ‡ Civil and Environmental Engineering; University of California; 721 Davis Hall; Berkeley; CA 94720-1710; U.S.A. SUMMARY The uncertainty in the seismic demand of a structure (referred to as the engineering demand parameter, EDP) needs to be properly characterized in performance-based earthquake engineering. Uncertainties in the ground motion and in structural properties are responsible for EDP uncertainty. In this study, sensitivity of EDPs to major uncertain variables is investigated using the rst-order second-moment method for a case study building. This method is shown to be simple and ecient for estimating the sensitivity of seismic demand. The EDP uncertainty induced by each uncertain variable is used to determine which variables are most signicant. Results show that the uncertainties in ground motion are more signicant for global EDPs, namely peak roof acceleration and displacement, and maximum inter-storey drift ratio, than those in structural properties. Uncertainty in the intensity measure (IM) of ground motion is the dominant variable for uncertainties in local EDPs such as the curvature demand at critical cross-sections. Conditional sensitivity of global and local EDPs given IM is also estimated. It is observed that the combined eect of uncertainties in structural properties is more signicant than uncertainty in ground motion prole at lower IM levels, while the opposite is true at higher IM levels. Copyright ? 2005 John Wiley & Sons, Ltd. KEY WORDS: FOSM method; sensitivity analysis; shear-walls; reinforced concrete building; bre section modelling 1. INTRODUCTION Probabilisticevaluation of building performance under seismic loading is an important proce- dure for damage and loss estimations in performance-based earthquake engineering (PBEE). For this purpose, uncertainty in the seismic demand of the building (referred to as the ∗ Correspondence to: Khalid M. Mosalam, Civil and Environmental Engineering; University of California; 721 Davis Hall; Berkeley; CA 94720-1710, U.S.A. † E-mail: mosalam@ce.berkeley.edu ‡ Associate Professor. § Doctoral candidate. Contract=grant sponsor: National Science Foundation; contract=grant number: EEC-09701568 Received 29 July 2004 Revised 22 March 2005 Copyright ? 2005 John Wiley & Sons, Ltd. Accepted 12 April 2005