END DETAILING EXPERIMENTAL STUDY ON THE SEISMIC PERFORMANCE OF ALL-STEEL TUBULAR BRBS

Abstract

To clarify the effects of end details on the seismic performance of a new type of All-Steel Tubular Buckling  Restrained  Brace  (AST-BRBs)  constructed  by  placing  a  steel  tube  as  a  core  member within another steel tube as an external restraint (pod), an experimental study was conducted. Seismic behaviors of six  specimens  (two non-pod  and four pod specimens) with three different end  detail  specifications  were  studied  under  cyclic  loads.  The experimental results show that AST-BRBs with end portions sent through a tube gradually increase in diameter with a lid welded to the end support plate. In addition to satisfying specified requirements, compared with the non-pod  specimen,  the  specimen  with  a  pod  can  dissipate  over 13times  more  energy  and  offers  a compressive bearing capacity of more than 2.2 times that of a nominal load capacity. Therefore, the seismic performance of this type of BRBis satisfactory and, due to their low cost, can be used as a suitable alternative to conventional bracing in engineering applications and steel structures.