Hysteretic model for steel–concrete composite shear walls subjected to in-plane cyclic loading

• Experimental results of 32 specimens are analyzed.
• Equations for the stiffnesses and loads are derived through a mechanics based model.
• Reduction factors for the Young’s moduli of concrete and steel are calibrated according to the experimental results.
• A quadri-linear backbone with negative post-peak stiffness and associated hysteretic rules are suggested.

Steel–concrete composite (SC) shear walls are being widely used as an alternative to reinforced concrete walls. Investigations on seismic behavior of SC walls have been conducted to develop design specifications for safety-related nuclear facilities. However, there is a lack of hysteretic models that can be used to predict structural performance as the structure approaches collapse. This paper presents (a) the analysis of experimental results of 32 SC wall specimens, and (b) the derivation and calibration of a quadri-linear backbone with negative post-peak stiffness and associated hysteretic rules. Different cross section shapes and loading configurations were used to test the SC wall specimens. Based on the experimental results, equations for stiffnesses and loads are derived from a mechanics based model, and basic hysteretic rules are employed to describe the response of SC walls subjected to in-plane cyclic loading. Calibrations are conducted to suggest the reduction factors for the Young’s moduli of concrete and steel that reflect the plasticity extension and damage accumulation.