Utility of Eccentric Bracing Frames in Seismic-Resistant, Sustainable Steel Building

Abstract

The aim of this chapter is to show the efficacy of eccentric bracing frame (EBF) in steel structure over moment-resisting frame (MRF) and concentric bracing frame (CBF). Eccentric bracing connections in steel structures help in stability of the structural systems against horizontal forces especially in seismic condition and also economize the connection. The EBF is usually assumed to be pin-ended, but the beam–column joints may be designed for pin-ended or for full connectivity. The EBF has several desirable features as a system for resisting seismic forces. The system can be designed for appropriate stiffness and drift control, comparable to that obtained using concentric bracing. The link beam is designed to yield in shear or flexure prior to initiation of buckling or yielding of the bracing member in compression or tension. In this chapter, the behavior of a 2-D steel frame is observed under seismic loading condition. The ductility and brittleness of the frames are compared with respect to time period of vibration and ratio of static base shear vs. dynamic base shear. The superiority of the EBF system is clearly visible than MRF and CBF system comparing the time period of vibration and base shear participation. The EBF system acts as metallic damper in the building fames.