Testing of Buckling-Restrained Braces with Replaceable Steel Angle Fuses

Abstract

This research focuses on a new type of buckling-restrained brace (BRB) with replaceable steel angle fuses. The proposed BRB offers ease of postearthquake examination of fuse damage, convenient and prompt replacement of damaged fuses, and reuse of the buckling restraining elements. To investigate seismic behavior of the proposed BRB, seven brace specimens are tested. The test parameters varied in these specimens include fuse design, fuse material, debonding material, and loading protocol. Test results show that the proposed BRB can exhibit stable hysteretic behavior up to fairly high fuse strain levels. Failure modes of the specimens are found to be ruptures of the angle fuses, as expected. The compression strength adjustment factors and the cumulative plastic deformations of the specimens are found to satisfy the requirements specified by the current U.S. seismic design provisions for structural steel buildings. Moreover, the authors demonstrate that specimens repaired through fuse replacement remain satisfactory in following tests. Furthermore, rupture failures of the proposed BRB can be captured by the modified Park–Ang damage measure.