Experimental Behavior and Design of Rectangular Concrete-Filled Tubular Buckling-Restrained Braces

Abstract

This paper proposes a new design method for concrete-filled tubular buckling-restrained braces (CFT-BRBs) by incorporating the confinement effect on pre-buckling rigidity. A series of experiments are performed to investigate the effects of concrete strength and sectional dimension on the initial stiffness, ultimate strength, and energy dissipation behaviors. Experimental results indicate that the confined concrete plays an important role in the energy dissipating capacity of CFT-BRBs. On the other hand, the sectional dimensions of the steel tube and core are influential factors governing the ultimate failure modes of CFT-BRBs. The findings in study provide technical supports to optimize the design methods for ductile seismic performance of CFT-BRBs in low-rise and high-rise steel buildings.