Seismic performance and design of replaceable links in structural systems: review

Replaceable links are engineered structural fuses designed to absorb and dissipate seismic energy through controlled, inelastic deformation during earthquake events. Acting as sacrificial elements, they are designed to yield preferentially under seismic demands, thereby shielding primary structural members from significant damage. Their defining characteristic of replaceability facilitates rapid post-earthquake functional recovery by enabling efficient removal and installation, which substantially minimises structural downtime. These operational benefits have established replaceable links as a significant and sustained research theme within earthquake engineering over recent decades. This review comprehensively examines their implementation across diverse structural systems, such as eccentrically braced steel frames, moment-resisting frames, shear walls, steel tube structures and steel–concrete composite systems. Through a critical synthesis of experimental studies and numerical simulations conducted by researchers worldwide, various link typologies and their respective performance characteristics are evaluated in this paper. Furthermore, key performance parameters and the factors influencing them are identified. The consolidated insights provide a theoretical basis for optimising the design and application of replaceable links, with the ultimate goal of enhancing structural seismic resilience and mitigating earthquake-induced losses.