Study of the seismic performance of steel frames in the elliptic bracing

Abstract

This article appraises the seismic performance of a new braced steel structural system called elliptic braced moment resisting frame (ELBRF). Apart from improving the behavior of a structure, ELBRF is found non-problematic for the bracing system in a given architectural space. In this study, a single cycle time has been used for evaluating the proposed ELBRF. Here, methods of seismic design of structures as well as effective parameters in the seismic design of steel braced including ductility factor, overstrength coefficient and behavior factors, which were obtained by using capacity curves, have been presented through an adaptive pushover analysis (APA). Result of the nonlinear analysis showed that the strength and capacity of energy dissipation in the elliptic bracing system (ELBRF) is more than the system of special moment resisting frames (SMRF), coaxial braced frame (CBF) X-Braced, Inverted-V Braced CBF. Likewise, the permitted relative displacement, where the braced frame reaches to step buckling, is more in ELBRF.