Topology Optimization of Horizontal Links in Multi-story Eccentric Braced Frames

In recent years, the adoption of additive manufacturing has become important, primarily driven by an imperative to minimize material usage and mitigate environmental impacts associated with climate change. The integration of topology optimization and additive manufacturing techniques has paved the way for the fabrication of complex geometries that are both cost-effective and material efficient, enabling structures that would be challenging to produce using traditional manufacturing methods. Concurrently, the application of eccentric braced frames with link elements has seen a notable increase, attributed to their enhanced seismic resistance capabilities compared to concentric braced frames. This study integrates topology optimization and AM to design optimized shear links for EBFs that outperform standard HEB European sections. Finite Element Models were developed in Abaqus to simulate both monotonic and cyclic loading scenarios. Pushover and cyclic analyses were performed on single-, two-, and three-story frames to assess the performance of the optimized links. Through pushover analysis, the results show that employing optimized HEB sections leads to a significant reduction in steel volume while simultaneously enhancing both the yielding and ultimate strength of the structure, with some multi-story frames demonstrating a twofold increase in performance over standard designs. Moreover, cyclic performance analysis of models with optimized links underscores a notable increase in the base shear ultimate force with marked improvement in the effective stiffness compared to models with standard sections. However, this was accompanied by a reduction in energy dissipation and the viscous damping coefficient.