Behavior of shear-dominant thin-walled RC structures

Reinforced concrete (RC) shear-dominant walls can fail suddenly at lower ductility levels, which can lead to catastrophic damage. Accurate modeling of shear-dominant RC walls is therefore essential. In this paper, fiber beam elements, which are proven to be computationally very efficient, were developed to model the behavior of thin-walled RC shear walls. Concrete and steel were considered as separate materials, and are combined at the section level to describe the behavior of the reinforced concrete member. Concrete was modeled as an orthotropic material in which the principal directions of total stresses were assumed to coincide with the principal directions of total strains, thus changing the directions continuously during the loading. The constitutive model follows the Softened Membrane Model (SMM) in which the compressive strength of concrete is reduced as a function of the lateral strain. The model was subsequently used to conduct a series of numerical studies to evaluate the effect of several parameters affecting the nonlinear behavior of the shear dominated wall. These parameters include the aspect ratio, the transverse reinforcement ratio, the axial force, and the concrete compressive strength. These studies resulted in several important conclusions regarding the global and local behavior of wall systems.