Estimation of Effective Stiffness and Plastic Moment of RC Rectangular Shear Walls

Seismic behavior of RC structures requires estimation of their dominant deterioration, collapse mechanism and assessing the possibility of their occurrence. How a structural component or structural system behaves under seismic loading is influenced by behavioral measures. Seismic collapse resistance depends on the strength, stiffness, and deformation capacity of individual structural components and the overall seismic resistance force system. Each of these behavioral measures is related to design parameters and the designer needs to know the relations among behavioral measures and design parameters. In order to illustrate such requirement, the relations for effective stiffness and plastic moment as a function of design parameters have been investigated for RC shear walls using numerical simulations calibrated with published laboratory tests. The summary of OpenSEES numerical simulations for modeling of plastic hinges hysteretic behavior of RC shear walls and estimation of empirical relations among wall hysteretic indices and design parameters are presented. The considered main design parameters are wall dimensions, axial force, reinforcement ratios, and end element design parameters. Through an extensive investigation some empirical relations are developed and their accuracy is also investigated.