Seismic Performance Assessment of L-Shaped Reinforced Concrete Columns

This paper presents an experimental investigation carried out on 10 reinforced concrete (RC) columns with L-shaped sections subjected to simulated seismic loadings. The primary objective of the study was to assess the suitability of using L-shaped RC columns in regions of low-to-moderate seismic risk The variables of interest included the axial load, loading direction, and aspect ratio. The specimen performances were analyzed and discussed in terms of crack patterns, hysteretic response, curvature distribution, displacement decomposition, strain profile, and energy dissipation capacity. Results highlighted that the L-shaped columns possessed good seismic resistance, that failure mechanism of L-shaped columns was mainly governed by vertical splitting cracks, and that shear strength of L-shaped columns was not significantly affected by the level of applied axial force and the direction of horizontal force while initial stiffness was considerably affected by aspect ratio. Further analysis showed that ignoring the contribution of flanges, the shear equation (special provisions for walls) in ACI 318-11 yields good estimations of shear strength for the cases of L-shaped columns.