Direct displacement-based seismic design of steel concentric braced frame structures

Abstract

The direct displacement-based design (DDBD) procedure is well developed and used for designing reinforced concrete moment resisting frame structures, wall structures and bridges. However, there is limited number of studies available on designing steel concentric braced frame (CBF) structures using DDBD approach. Therefore, it is necessary to develop a DDBD procedure for CBF structures. On this regards, this paper proposes a DDBD procedure for steel CBF structures. The proposed procedure utilises the yield displacement shape derived on the basis of tensile yielding of the braces, and the equivalent viscous damping equation of the system proposed by Wijesundara et al (2011) as a function of system ductility and non-dimensional slenderness ratio for steel CBF structures. Finally, the performance of four steel CBF structures designed according to the proposed DDBD procedure is studied using non-linear dynamic response of the structures. The results show that the performance of CBF structures is in good agreement with the design considerations.