Experimental and theoretical study on seismic behavior of non-seismically designed shear walls with moderate shear span-to-length ratios

This study aims to examine the seismic performance of non-seismically designed shear wall with moderate shear span-to-length ratios (SLR) under relatively high axial loads. Four wall specimens with varying parameters, such as shear-to-flexure strength ratio, SLR, and axial load ratio (ALR) are fabricated and tested under cyclic loads. The experimental results, encompassing crack patterns, failure modes, hysteretic behavior, stiffness degradation, energy dissipation, and reinforcing bars strains, are presented and discussed. Digital Image Correlation (DIC) technology is employed for a comprehensive analysis of the crack patterns and deformation components of the tested specimens. The effective stiffness, including both effective flexural and shear stiffness is obtained through a deformation components analysis. These values are compared to the recommended values provided in FEMA 356 and ASCE 41-17. Moreover, the generalized forcedeformation relationships in ASCE 41-17 are evaluated using the experimental results. Subsequently, a novel theoretical model for determining the force-deformation relationship of shear walls, incorporating stiffness degradation and flexural-shear interaction, is proposed and validated with test results. The results demonstrate that the proposed model effectively predicts the relationship between force and displacement.