Experimental Testing and Design of High Performance Shear Links for Eccentrically Braced Frames

Steel links inside Eccentrically Braced Frames (EBFs) can be classified as either short, intermediate or long. The more commonly used short links yield primarily in shear and dissipate incoming energy inside the web of the link. Advances in shear link research and industry practice, particularly the increased use of bolted links, have allowed greater freedom in the design of the link section, as the section used can be decoupled from the collector beam section. Seven shear link specimens were tested inside a full scale EBF set up, and were subjected to AISC’s 2005 shear link loading protocol. Increasing levels of rotation were applied to links of varied cross-sections and intermediate stiffener spacings. Links with low web aspect ratios performed to a higher rotation than past research would have suggested, and when intermediate stiffeners were removed, they performed to an even higher rotation. Recommendations for design are presented, including a relaxation of the stiffener spacing equations when web aspect ratio criteria are met. A provision is also included to allow greater rotational ductilities in EBF frames with low web aspect shear links.