Hysteretic Behavior and Multi-Wave Buckling of Assembled Buckling-Restrained Braces Wrapped with Fiber Clothes

To rapidly repair the damaged buckling-restrained brace serving as energy absorption member during earthquake, the assembled method of wrapping the component with FRP cloth is proposed. In this research, a series of cyclic tests on six assembled buckling-restrained brace (ABRB) wrapped with three kinds of FRPs (carbon fiber, glass fiber and basalt fiber) were performed. The tested results show that all the specimens show excellent hysteretic performance and similar damage mode, namely core unit fracture, whilst short specimens show better ductility, but worse energy dissipation ability than the long specimen. A parametric analysis is performed based on a finite element model validated against the test result. The effects of the gap and friction force between core unit and infilled concrete and the thickness of FRP cloth are analyzed. The modes of multi-wave buckling of core units are exhibited, and the influence of multi-wave buckling on component performance is evaluated. Based on the test and simulation analysis, CFRP is suggested to be used in the wrapped buckling-restrained brace.