Shear Strength Model for Reinforced Concrete Bridge Columns with Multispiral Transverse Reinforcement

Abstract

A shear strength model is proposed for reinforced concrete bridge columns with multispiral transverse reinforcement. The proposed model consists of a proposed discrete computational shear strength model for multispiral reinforcement and shear strength models for concrete and axial load adopted from the literature. The proposed discrete computational model calculates shear strength from each discrete location of the interception between the shear crack and multispiral reinforcement. Furthermore, the model considers the critical location of the shear crack, shear crack angle, direction of shear, and effect of the compression zone. The proposed model together with the Caltrans SDC model, Sezen’s model, and Priestley’s model are used to predict the shear strength of multispiral columns tested in the literature. Comparison between the prediction and test result shows that the proposed shear strength model produces the best prediction in terms of the mean and standard deviation of the ratio of experimental to predicted shear strength. Based on analysis and test observations, equations to estimate the compression depth of multispiral columns at the ultimate condition and the shear crack angle are proposed to be used in the proposed discrete computational shear strength model.