Study of GFRP Steel Buckling Restraint Braces

Buckling-restraint braces (BRBs) are used extensively in seismic-resistant structures. They consist of a core energy dissipation and external restraining component. A novel glass fiber-reinforced polymer (GFRP) steel BRB is proposed. In the GFRP steel BRB, four GFRP pultruded tubes, which are tied together by GFRP wrapping layers, are used to restrict core steel component buckling instead of conventional steel tube and infilled concrete or mortar. This GFRP steel BRB is extremely lightweight. Techniques for manufacturing GFRP steel BRB were developed for convenient large-scale industrialized production. Quasi-static tests were carried out to validate the performance of the GFRP steel BRB under cyclic loading. The tests focused mainly on energy dissipation capacity and ultimate failure mode of the proposed GFRP steel BRB. The effect of applying additional reinforcements to the GFRP external restraining component on the performance of GFRP steel BRB was also investigated. The performance of the appropriately designed GFRP steel BRB was satisfactory; however, it is prone to damage from local failure of external restraining GFRP components and additional reinforcements may enhance its performance. (C) 2015 American Society of Civil Engineers.