Modelling of framed shear walls for non-linear analyses of reinforced concrete buildings

The increased use of shear walls in buildings has necessitated the study for a better understanding of the modelling aspects of a wall and its behaviour under lateral loads. In a framed shear wall, the behaviour of the infill wall panels under lateral loads is governed by shear deformation and the frame-panel interaction. In the present study, a reinforced concrete low-rise multistoreyed building with a centrally located framed shear wall was investigated for two approaches of modelling the non-linear behaviour of the wall. In the first approach, the wall was modelled using multi-layered membrane elements (refined model). In the second approach, the wall was modelled using equivalent column elements (simplified model) with lumped plasticity at the ends. Pushover analysis and incremental dynamic analysis (IDA) were performed using these models. It was observed that the pushover curves and the IDA plots for both the models are reasonably close. From the pushover analyses, the prediction of lateral strength by the simplified model was slightly lower than the refined model due to the idealisation of the equivalent column elements. Nevertheless, the modelling of a framed shear wall using equivalent column elements is adequate in terms of quantifying the lateral stiffness, strength and overall behaviour of the structure under lateral loads, provided the hinge properties are defined properly.