PEER has just published Report No. 2015/12 titled “Shear-Flexure Interaction Modeling for Reinforced Concrete Structural Walls and Columns under Reversed Cyclic Loading”. It was authored by Kristijan Kolozvari, Kutay Orakcal and John Wallace.
A novel analytical model that captures interaction between axial/flexural and shear responses in reinforced concrete (RC) walls and columns under reversed-cyclic loading conditions has been developed and implemented in the computational platform OpenSees. The proposed modeling approach incorporates RC panel behavior described with a constitutive fixed-strut-angle panel model into a two-dimensional Multiple-Vertical-Line-Element-Model (MVLEM) formulation. The coupling of axial and shear responses is achieved at the macro-fiber (panel) level, which further allows coupling of flexural and shear responses at the model element level. New classes added to the existing OpenSees library include: baseline MVLEM element with uncoupled axial/flexural and shear behavior, Shear-Flexure-Interaction MVLEM element, two-dimensional material model based on the fixed-strut-angle constitutive RC panel model, uniaxial material model for concrete, and uniaxial material model for steel. Applications of the analytical models to quasi-static analysis of RC walls and columns, with comparisons of the analytical and experimental load-deformation responses, are presented. In addition, a dynamic analysis example for a building wall-frame system using the proposed shear-flexure-interaction model is provided. Response comparisons reveal that the implemented analytical models capture well the experimentally measured behavior of RC structural walls and columns. Based on the comparisons presented, model capabilities are assessed and potential model improvements are identified.