Numerical analysis of perforated steel fuse in timber-braced frames

The inherently brittle nature of timber limits its effectiveness in seismic applications, particularly in high-rise structures where ductility is essential for energy dissipation. Although timber-braced frames (TBFs) offer a potential solution, current design standards lack specific provisions for their implementation. Unlike steel bracing, which relies on buckling in compression and yielding in tension to improve system ductility, timber bracing requires well-designed connections that yield at the brace ends to dissipate energy, while the brace itself remains elastic. One practical approach to achieving this involves integrating yielding fuses, such as perforated steel plates, to enhance ductility and localize damage in replaceable components during seismic events. This study investigates the role of perforated steel plates as seismic fuses in TBFs, focusing on flexural yielding mechanisms, particularly through long slot-shaped perforations. A comprehensive numerical parametric study was conducted to assess key factors influencing the performance of these plates. Results indicate that increasing the perforation length to 100 mm improves the ultimate deformation up to 26 mm but reduces load capacity. However, this reduction can be mitigated by increasing the number of link elements. By optimizing both slot length and the number of links, a 50 % increase in ultimate deformation was achieved without compromising load capacity compared to previous studies.