Seismic Analysis and Evaluation of Y-shaped EBF with an Innovative SSL-SSBC

During severe earthquakes, the ductility and energy dissipation capacity of shear links in Y-shaped eccentrically braced frames (EBFs) are crucial to achieve desirable seismic performance and structural safety. In this study, an innovative SSL-SSBC combining the advantages of a shear slotted bolted connection (SSBC) and a very short shear link is developed to improve the seismic performance of Y-shaped EBFs. Finite element (FE) analysis methods are first validated through comparison with existing experimental results for slotted bolted connection and very short shear links. Further, FE simulations of the SSBC, very short shear link with shear slotted bolted connection (SSL-SSBC), and Y-shaped EBF are conducted to determine their mechanical behavior systematically. The FE results demonstrate that a reasonable SSBC can effectively increase the ductility and energy dissipation capacity through friction slipping, allowing the SSBC to maintain elastic behavior throughout the entire range of seismic loading, while the very short shear link in the SSL-SSBC could undergo severe damage to dissipate seismic energy. As expected, the SSL-SSBC is capable of working as both a shear dissipation damper and a metallic ductile damper in the Y-shaped EBF. This study also clearly identifies that no yielding or damage of the very short shear links occurs during small and medium earthquakes, and the deformation and damage of the very short shear link can be minimized during severe earthquakes, allowing the seismic resilience capacity of the Y-shaped EBF to be dramatically enhanced.