Lateral behaviour of steel plate shear wall with cold-formed steel strips reinforcing door opening

Abstract

Holes in the walls of buildings are occasionally necessary to fulfil buildings’ functional requirements. When a steel plate shear wall (SPSW) is used as the primary lateral force-resistant structural member in a building, the effect of such openings on the mechanical properties of the SPSW is non-negligible. In this study, reinforcement of SPSWs with door openings using prefabricated cold-formed steel (CFS) strips is proposed. The proposed method can improve the mechanical properties of SPSWs with openings without inducing the residual deformation and stress caused by the typical welding reinforcement method. Cyclic loading tests were conducted to analyse the lateral resistance of two perforated SPSW structures reinforced using the proposed method: one SPSW with a door opening in the centre, and another with the door opening positioned at its edge. The test results showed that the openings reduced the lateral stiffness and strength of the structures. Specifically, a 30.84% decline in ultimate strength was observed for specimens with central door opening, while a 32.78% reduction was noted for specimens with edge door opening. Finite element models were derived and evaluated based on these results, and an SPSW with openings reinforced by CFS strips was modelled as equivalent to an SPSW without openings for analysis. The proposed simplified analysis model realises the weakening effect observed in a perforated SPSW by reducing the thickness of the equivalent unperforated SPSW. Finally, the equivalent analysis model (EAM) proposed herein was compared with experimental results, with the errors in yield strength and ultimate strength both within 5%. The results demonstrating that the proposed EAM is accurate and reasonable.