Performance-based plastic design method for buckling-restrained braced frames

This paper presents a performance-based plastic design (PBPD) methodology for the design of buckling-restrained braced frames (BRBFs). The design base shear is obtained based on energy-work balance using pre-selected target drift and yield mechanism. Three low-to-medium rise BRBFs (3-story, 6-story and 9-story) were designed by the proposed methodology and their seismic performance was evaluated through extensive nonlinear time-history analyses using forty ground motions representing the DBE and the MCE hazard levels. Both isotropic and kinematic hardening characteristics of buckling-restrained braces were considered in the modeling of their force-deformation behaviors. All BRBFs considered in this study reached the intended performance objectives in terms of yield mechanisms and target drift levels. Since PBPD is a direct design method, no iterations were carried out to achieve the performance objectives of BRBFs. (C) 2010 Elsevier Ltd. All rights reserved.