Evaluation on Flexural Deformability of Reinforced Concrete Columns with Wing Wall s

Abstract

Tests on reinforced columns with wing wall s were conducted in 2010 to investigate the flexural deformability following the shear tests in the previous years. The effects of the moment-to-shear ratios of loading, the reinforcement details and the width and length of the wing wall s on the flexural deformability were investigated. The specimens with thin wing wall s showed strength decay after the ultimate strength in flexure, due to the compression failure of concrete and buckling of the re-bars at the wall ends under the larger deformation amplitudes, while the specimens with thick wing wall s showed much less strength decay generally. If the edge was well confined, the strength decay was much smaller. All specimens were ductile and stable in flexural failure mode up to the maximum loading drift level. The damage to the column could relatively be relieved owing to the inelastic energy dissipation by the wing wall s. The ultimate strength and deformability are formulated for practical calculation based on a flexural theory and are compared with the test results, by which fair correlations are obtained. A simple formula on the deformability is derived based on the theory, by which the deformability rank of the member may be specified in the current code of seismic design.