Development of replaceable core all-steel buckling-restrained braces

This paper presents a replaceable core all-steel buckling-restrained brace (BRB). In this proposed BRB, as the encasing system composed of steel members alone without any filling material can be separated into two pieces by unfastening bolts, the damaged core plate inside the BRB can be easily replaced with the new one after an earthquake event. Two-directional slots at the end connections circumvent assembly and disassembly problems of the BRBs into the frames under residual drift. Pursuant the seismic performance of the proposed BRB, ten core plates, five encasement systems and one set of connection plates were produced and a total of ten full-scale subassemblage testing was performed. The connection set was used ten times and each encasing system was used two times. Based on the test results, all specimens exhibited stable behavior up to 4 % axial strain and the cumulative inelastic axial strain was computed as 744 for Specimen 1 and 643 for others. As a result of experimental and numerical studies, the seismic performance of the proposed BRBs, both in their first use and in the second use, satisfy AISC 341-22 requirements.