Enhancing the cyclic performance of shear links using longitudinal stiffeners

Shear links constitute the most crucial part of eccentrically braced frames. Their main responsibility is to dissipate the earthquake input energy away from the main structural members; therefore, keeping them responding within the elastic stage. However, the rotation capacity of vertical shear links directly influences the allowable interstorey drift of the eccentrically braced frame and the energy dissipation capacity. To enhance their rotation capacity and performance, transverse stiffeners in vertical shear links are proposed to be replaced with longitudinal stiffeners in this research. A numerical study is conducted, using Ansys Workbench, on fourteen shear links with different parameters to investigate their cyclic behaviour. The considered parameters are the stiffener configuration (transverse or longitudinal), web thickness, stiffeners number, stiffeners thickness, flanges width, and web aspect ratio. The influence of these parameters on the failure mode, hysteretic response, me-chanical parameters (strength, rotation capacity, etc.), ductility, cyclic web shear buckling, and energy dissi-pation is analysed and discussed. The results demonstrate that longitudinally stiffened shear links surpass conventional transversely stiffened ones in terms of strength, overstrength, rotation capacity, ductility, web shear buckling resistance, and energy dissipation. Additionally, it is found that the current design provisions of EN 1998-1 cannot accurately predict the yield shear strength of longitudinally stiffened shear links. Moreover, numerous remarks involved with the influence of different parameters on the cyclic performance of longitudinally stiffened shear links are presented and discussed.