The development of a novel analytical model to design composite steel plate shear walls under eccentric shear

Composite steel plate shear walls (CSPSWs) are widely used in construction due to their high stiffness and ductility. CSPSWs consist of boundary elements and a steel web plate stiffened with reinforced concrete (RC) panels in the two-sided or one-sided configuration. One-sided configuration, which is more popular, displaces the neutral axis from the centre of the steel plate toward the RC panel. However, no analytical formulation has been yet developed to predict the ultimate shear strength of CSPSW considering such an eccentric shear. In this paper, a new analytical method is first developed to estimate the ultimate shear strength of CSPSWs considering the eccentricity. Then, a 3D finite element (FE) model is developed and verified based on three different experimental studies. The FE model considers reinforcements of RC panel, shear connectors, and the interaction between the steel plate and RC panel. The developed FE models are used to analyse the precision of the proposed analytical method in estimating the ultimate shear strength of CSPSWs. The obtained results show that the presented approach can provide a reasonable estimation of the ultimate shear strength of CSPSWs. It is shown that the presence of torsion due to the eccentricity reduces the ultimate shear capacity. The proposed method predicts the ultimate shear strength more accurately than the AISC method, which does not consider the effect of torsion.