THE HYSTERETIC BEHAVIOR AND WORKING MECHANISM OF SELF-CENTERING STEEL BUCKLING-RESTRAINED BRACES

A novel self-centering steel buckling-restrained brace (SC-SBRB) is proposed, which is mainly comprised of a buckling-restrained energy-dissipation system and a self-centering system of pre-pressed disc springs in parallel. The fundamental configuration and working mechanism of the SC-BRB are introduced. A restoring force model that accurately describes the unique hysteretic behavior of the SC-SBRB is established. Four solid numerical models of SC-SBRBs with different design parameters are built using ABAQUS finite element software. The hysteretic behavior and self-centering performance of the SC-SBRB under cyclic loading are studied and compared with the calculation results of the restoring force model. The results demonstrate that the SC-SBRB exhibits a stable and full flag-shaped hysteretic response under cyclic loadings, and that the proposed restoring force model is capable of accurately predicting the mechanical properties at different stages. The self-centering performance of the SC-SBRB is gradually exerted as the initial pre-pressed force of disc springs increases, while the residual deformation is reduced simultaneously. The maximum residual deformation ratio of the brace is decreased to 0.039% when the self-centering ratio is 1.0, indicating a good coordination of the self-centering and energy-dissipation performance.