Analytical Prediction of the Inelastic Response of RC Walls with Low Aspect Ratio

In reinforced concrete shear walls subjected to seismic loads the flexural, web shear and sliding shear mechanisms are activated. The measurements obtained from the tests of 11 wall specimens with aspect ratio 1.0 and 1.5 are used in order to set up analytical models that predict the deformations associated with each mechanism and the corresponding strength. The quantity and arrangement of the reinforcement of the specimens were chosen to ensure a flexural type of failure. It was observed during the tests that the web shear deformation increased until maximum strength was achieved. After the point of maximum strength, web shear deformations decreased, while sliding shear deformations along the base main flexural crack increased. Together with the previously noted web shear and sliding shear deformations, flexural deformations were also measured. The relationships proposed for the description of the strength and the deformation characteristics of these mechanisms derived from appropriately modified existing models along with new ones. The analytically calculated quantities are compared with the experimental measurements and a good match is noted. It is concluded that in shear walls with low aspect ratio sliding shear deformations appear at the base plastic hinge, even in the case where the flexural behavior initially prevails the response. Neglecting of such shear deformations results in underestimating shear forces at the base of other vertical structural elements.