Numerical and experimental investigation on a BRB confined with partially carbon fiber reinforced polymer (CFRP)

摘要

Buckling-restrained braces (BRBs) have been spread widely, especially in high seismic hazard zones due to their excellent energy absorption capacity. BRBs are composed of a main load-carrying steel core restrained with other elements mostly made of concrete and steel casing to preserve it from buckling. Although BRBs provide excellent cyclic behavior, a problem is with their heaviness, which leads to difficulties such as installation and transportation. This study presents a numerical and experimental investigation on a BRB with a new proposed restraining system composed of concrete panels confined with partially carbon fiber reinforced polymer (CFRP) strips to reduce the weight of the brace. Finite element analysis was first verified and then conducted to find the optimum arrangement of CFRP strips. A cyclic test was then performed on a half-scale BRB frame to assess the performance of the brace. The brace remained intact until 2.5% drift and finally failed from the end portion in a 3% drift. In addition to satisfying the requirements of AISC-341, the proposed brace reduces the weight of the brace by at least 30%, depending on the size of the brace.