Experimental testing and analytical modeling of CFS shear walls filled with LPM

Cold-formed steel (CFS) shear walls filled with lightweight polymer material (LPM) is an efficient structural system which can provide high lateral stiffness and strength to resist lateral loads. Despite the significant advantages, the nonlinear behavior of the CFS shear wall filled with LPM is not fully understood. In this study, a total of seven full-scale CFS shear walls filled with LPM were tested under cyclic loads. The test parameters included different LPM types, X-shaped bracing configurations, sheathing types and wall openings. The failure modes hysteresis curves, envelope curves, feature values, ductility ratio, stiffness and energy dissipation of CFS shear wall with and without filling LPM were systematically compared. The experimental data reveled that this type of shear wall showed higher load carrying and energy dissipation capacities than CFS framing wall without LPM. To assist with the design of CFS shear walls filled with LPM, a modified strut-and-tie model was proposed. The modified strut-and-tie model was validated using the experimental data. The result demonstrates that the proposed model can be utilized to accurately estimate the load carrying capacity of CFS shear walls filled with LPM. The presented experimental and analytical results can be used by engineers to design CFS shear walls filled with LPM for earthquake engineering applications.