Experimental Investigation of Steel Braces Installed with Intentional Eccentricity Using Gusset Plate Connections

The present paper proposes an improved design of conventional buckling braces (CBBs) by introducing intentional eccentricity along the brace length. The proposed brace is named the Brace with Intentional Eccentricity (BIE). Due to the inherent action moment caused by the eccentrically applied axial force, the BIE bends uniformly form small story drifts and sustains tri-liner behavior under tension, while under compression moves smoothly into the post-buckling behavior. BIE provides independent design of strength and stiffness, large post-yielding stiffness and high ductility by delaying the appearance of mid-length local buckling. The present experimental study consists of three specimens subjected to cyclic flexural load protocol with variable intensities from 0.10% to 4.0% story drift angle. Gusset plate connections designed to accommodate inelastic rotations were used to connect the bracing members in the loading frame. Different values of the applied eccentricity were tested and comparisons with a CBB were made to examine and evaluate various aspects of the BIE cyclic behavior.