EXPERIMENTAL STUDY ON BUCKLING-RESTRAINED BRACES USING STEEL MORTAR PLANKS : Part 3 Buckling behavior of the core plate

Abstract

It is considered that in the buckling-restrained bracing, its core plate is stiffened with a restraining part to prevent buckling. In reality, however, high-order buckling mode occurs in the core plate, when the buckling strength of the core plate is approximately equal to the yield strength of its cross-section. The results of testing of buckling-restrained braces conducted by the authors indicate that in the final phase of the testing, local deformation occurs in their core plates, and at this point, their load-bearing capacity often starts to decline. In order to understand in full detail the mechanism of buckling observed in the core plates, more specifically, how high-order buckling mode develops into local deformation in some core plates, the authors conduct strain measurement using strain gauges attached to the core plates and analyze the obtained data. The authors also consider the relationship between high-order buckling mode and the performance aspect such as energy absorption rate.