Investigation of the Concentric Bracings Response Equipped with Lateral Restricted Local Fuse under Cyclic Loading

Abstract

Concentric bracings (CB) are one of the most prevalent lateral load bearing systems in steel structures. These bracings have a remarkable lateral stiffness and strength, but their compressive buckling prevents them from being ductile and absorbing optimal energy. Consequently, in recent decades, researchers have conducted extensive studies to improve the concentric bracing behavior, which resulted in the development of different design and execution methods for concentric bracings. In this paper, by using numerical and experimental studies, a new method is proposed to improve the behavior of concentric bracings. In this method, a local fuse (LF) is used along the brace. This fuse is restrained by auxiliary elements (AE) to prevent its local buckling under compressive load. This makes the brace behaves in a similar manner in both tensile and compressive cyclic loads, resulting in ductile behavior and high-energy absorption. In this study, by using numerical results, an investigation is done for proper position of the fuse along the braces and its optimal shape and length. In addition, an analytical study has been performed comparing the structural behavior of concentric braces with LF-AE braces. The results have been demonstrated that LF-AE braces have better performance than concentric braces.

Keywords

• steel structures
• concentric brace
• local fuse
• ductility
• energy dissipation capacity
• loading capacity