System-Level Displacement- and Performance-Based Seismic Design Parameter Quantifications for an Asymmetrical Reinforced Concrete Masonry Building

This paper focuses on analyzing the performance of structural walls comprising the seismic force resisting system (SFRS) in a scaled asymmetrical fully grouted reinforced masonry (RM) building tested under quasi-static loading. The in-plane tensile and compressive strains calculated at the wall toes and the curvature profile along the wall height as well as the contributions of the flexural and the shear deformations to the overall wall displacements were quantified. The component-level (when the walls were tested individually) responses were compared with those at the system level (in a building). In addition, key input parameters for displacement-based seismic design approaches, including stiffness degradation and the trend of the building’s effective period increase as well as the variation of hysteretic damping, were quantified. Moreover, the building energy dissipation levels were compared with those generated during the individual wall tests to quantify the contribution of each component to the overall system-level performance. Finally, within the context of performance-based seismic design, the damage states of the building walls at different loading stages were identified and the damage levels, correlated to the maximum developed crack widths in the walls, were quantified utilizing a digital image correlation-based technique. Based on the analyses conducted, it was observed that wall curvatures and the extent of plasticity from the building test were not consistent with those based on the individual wall tests. In addition, the current test results showed that the total energy dissipation of the building does not only result from the walls aligned along the loading direction, but also from orthogonal walls engaged through the floor slabs as a result of the building twist. Finally, the study is expected to contribute to understanding the system-level performance of RM SFRS in order to facilitate their adoption in the next generation of performance-based seismic design codes in North America.