This paper presents a design method for the seismic shear strength of RC bridge columns. The design approach is based on the principle tensile stress for the diagonally-cracked concrete column with empirical modifications. The proposed method accounts for the effects of concrete compressive strength, axial load level, shear span-to-depth ratio, longitudinal reinforcement ratio, and displacement ductility ratio. The analytical predicted shear strength results for forty-seven rectangular columns and thirty-eight circular columns are in good agreement with the experimental results. The average ratio between experimental shear strength to predicted strength is 1.21 for circular columns and 1.25 for rectangular columns. The proposed model is compared with the ACI 318-11 and ECP-203 codes, as well as the design approaches of the Caltrans SDC and modified UCSD model. Also, the parametric studies show the reliability of the method for calculating the shear strength of bridge columns with different geometrical and material parameters. |