Seismic Behavior of Shear-Critical Reinforced High-Strength Concrete Columns

An experimental investigation has been conducted to examine the seismic behavior of seven shear-critical, high-strength concrete columns and one normal-strength concrete column. The effects of compressive strength of concrete, shear span-to-depth ratio, axial-load ratio, and transverse reinforcement amount on shear capacity, ductility capacity, energy dissipation, and stiffness degradation were critically examined. Test results indicate that increase in shear span-to-depth ratio and confinement effectiveness, and reduction in axial load, resulted in increase of energy dissipation capacity and ductility. Compared with the test results, predictions of shear strength from three available models may not be directly applicable to the shear-critical, high-strength concrete columns, whereas the calculated values by the truss-arch model considering the condition of deformation compatibility are shown to be consistent with the test data.