Yield displacement is an important parameter in appropriately evaluating a seismic capacity of a building. To understand the detailed mechanics of flexural column deformation up to yielding of flexural rebar, deformation characteristics are measured with high resolution in a static loading test of five column specimens. Measured horizontal displacements are, then, separated into three displacement components, i.e., flexural displacement, shear displacement, and anchorage displacement, to find they are well simulated by classical flexural theory based on Bernoulli-Euler assumption, elastic shear theory considering uncracked horizontal section, and elastic deformation theory of stub considering flexural stress transferred from the column, respectively.
