The research presented here seeks to advance nonlinear analysis of reinforced concrete flexure-controlled walls to improve understanding of the earthquake behavior of these components as well as to provide tools to support performance assessment. Previous research shows that fiber-type force-based beam-column elements can provide accurate simulation of the cyclic response, including drift capacity, of walls exhibiting flexure-controlled response. Accurate simulation of drift capacity and flexural failure modes requires regularization of concrete material response in compression and specification of a strain at which reinforcement loses strength due to buckling. For walls with high shear stress demand, which are not shear critical and exhibit flexural rather than shear failure, shear influences the flexural failure mode. Flexural walls with high shear exhibit a compressive-shear failure that is less ductile than a compression- or tension-controlled flexural failure. Compression-shear interaction and the compression-shear failure mode cannot be captured by the fiber-type beam-column element model. Here, flexure-shear interaction and compression-shear failure are investigated using continuum analysis. The results of continuum analyses indicate that high shear stress demands result in a diagonally oriented strut across the wall height that elongates the compression zone beyond that determined by a plane-sections-remain-plane analysis; elongation of the compression zone is exacerbated by increased wall cross-sectional aspect ratio. This response mechanism results in walls with high shear stress demands being vulnerable to web and boundary element crushing, which induce the compression-shear failure and compromise drift capacity.
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