Behrouz Shafei - MSc Structural Engineering
Pierino Lestuzzi - Lecturer
Masoud Motavalli - Assistant professor
Rasoul Mirghaderi - Assistant professor

Concentrically Braced Frame is a structural system which resists lateral forces by forming a vertical truss system and it has also become one of the most common framing systems in regions of high seismicity. Researches on the behavior of CBFs commenced in the 1960s and now provisions for the analysis , design , and detailing of CBFs have been introduced into seismic regulations and guidelines. Braced framing systems proved popular in regions of high seismicity because materials saving could be achieved with respect to moment-resisting frames and control of frame drift due to high earthquake-induced inertial forces could be efficiently realized. Because of extensive usage of CBFs as the earthquake resisting system in typical steel buildings, and also existence of a variety of mistakes in configuration and design of this system , this paper tries to describe the most important factors which should be considered necessarily in correct design of CBs according to seismic provisions given in AISC (American Institute of Steel Construction) hereafter referred to as AISC-Seismic Provision . This code id one of the most reliable cods which is used widely in consideration of seismic behavior and also design of steel building in areas of high seismicity.

Concentric Braced frame (CBF) , Seismic Provisions , Steel Buildings, Earthquake-Resisting System , Ductility