Seismic-resistant CFS walls braced with pre-tensioned UHS steel bars: Design and construction of a building mockup

• Published in: Thin-walled structures 2025-03, Vol.208, Article 112818
• Main Authors: Fiorino, Luigi, Campiche, Alessia, Tartaglia, Roberto, Landolfo, Raffaele
• Format: Article
• Language: English
• Subjects: Case study; Cold-formed steel; Numerical modelling; Seismic design; UHS steel bracing
• ISSN: 0263-8231
• DOI: 10.1016/j.tws.2024.112818

•The paper presents the design and the construction of a real mock-up two-story exhibition building having a load bearing cold-formed steel (CFS) structure, where the lateral force resisting system (LFRS) is represented by an innovative hybrid wall made of CFS studs and tracks laterally braced by ultra-high strength (UHS) steel pretensioned diagonal bars.•The resisting walls were dimensioned starting from a proper design procedure and an analytical model developed to evaluate both the elastic stiffness and resistance of the introduced solution. The effectiveness of the adopted analytical model was validated against the experimental results performed in a previous publication.•Starting from the experimental results on the individual walls, an advanced numerical model was developed and validated. The non-linear performance of the designed and erected structure were investigated by means of push-over analyses performed on the 3d model of the entire structure.•The results of the static non-linear analyses show that all the structural elements behave in elastic range up to the plastic deformation within the UHS bars. A limited overstrength and ductility, mainly due to the UHS bar over resistance and the ultimate elongation, was observed in all the performed push-over analyses.•The light weight steel (LWS) solution introduced can also be used in high seismic areas, entrusting all the lateral resistant to the UHS bars, while all the others structural elements work for gravity loads while remaining in the elastic range. The paper presents the design and the construction of a real mock-up two-story exhibition building having a load bearing cold-formed steel (CFS) structure, where the lateral force resisting system (LFRS) is represented by an innovative hybrid wall made of CFS studs and tracks laterally braced by ultra-high strength (UHS) steel pretensioned diagonal bars. The hybrid CFS wall represents the result of the Italian research project, named ECCELSA, aimed to develop a CFS LFRS wall capable to be used where high resistance capacity is required, as in the case of medium-to-high seismic areas or medium-rise buildings. From the design and construction point of view, the real mock-up building presented in this paper appears to best satisfy the high safety, durability and eco-efficiency standards required by the building construction market. In order to verify the effectiveness of the design procedure adopted, a refined numerical model was developed and validat