Seismic performance and post-earthquake functional recovery of a modular steel plate shear wall with replaceable shear links

In modular steel plate shear walls (MSPSWs), grid modules arranged along the main diagonal tension-field path can mobilize the steel plate and concentrate inelastic demand in selected modules. However, replacing damaged grid modules after earthquakes remains difficult, and a repairable fuse element has not been explicitly incorporated into such systems. To improve post-earthquake repairability, this study proposes an MSPSW with replaceable shear links (RSL-MSPSW), in which grid modules follow the main diagonal force-transfer path, replaceable shear links are installed at beam mid-span, and a central corrugated steel plate is introduced to promote deformation compatibility among the grid modules. Two 1/3-scale original specimens with different upper grid module configurations were tested under quasi-static cyclic loading. After the first loading stage, damaged shear links were replaced and the repaired specimens were reloaded. The finite element (FE) models of the two original specimens were developed and validated against the test results, and then used to compare the RSL-MSPSW with a conventional SPSW and further examine the response of the proposed system. The test results showed that damage and inelastic deformation mainly developed in the grid module steel plates and shear link webs, while the main frame showed no visible macroscopic damage. The upper grid module configuration influenced the tension strip distribution in the central corrugated steel plate. The FE results showed reasonable agreement with the experimental cyclic response. Compared with the conventional SPSW, the RSL-MSPSW exhibited greater cumulative energy dissipation and a higher ductility index, with inelastic response concentrated mainly in the steel plates and shear links. After shear link replacement, the main lateral-resisting path was progressively restored. At θ = 2.07%, load-carrying capacity and stiffness recovery exceeded 90%, while cumulative energy dissipation recovery reached 65–73%. These results indicate that local replacement of damaged shear links can restore key mechanical performance.