Experimental study on assembled buckling-restrained braces wrapped with carbon fiber

Abstract:

The assembled bucking-restrained braces (BRB) wrapped with carbon fiber were proposed to improve the repairability and corrosion resistance. The damaged inner core element can be replaced by cutting the fiber material to make the outer restrained components separated, which makes the inner core to be replaced easily after earthquake, and the proposed assembled BRB can also improve the corrosion resistance of outer steel tube. Four assembled BRB specimens were tested by quasi-static tests, and different loading schedules and constraint ratios were considered. The results show that new assembled BRBs could undergo fully-reversed axial yielding cycles nearly without loss of stiffness and strength, and the ductility and energy absorption capacity are large enough. The carbon fiber cloth successfully connects outer confined elements and effectively resists the lateral thrust exerted by inner core. Multi-wave buckling phenomenon occured in the inner core element, and deformation appeared in wrapped material under compression load. The hysteretic curves of BRBs “jump” in the compression stage. The hysteretic behavior and energy dissipation capacity of BRBs get worse with more obvious multi-wave buckling. The new assembled BRB has good hysteretic behavior and provides a new way to realize assembling of BRBs.