Effects of cross-sectional shape on the reliability of RC columns

This paper studies the effects of cross-sectional shape and rebar configuration on the reliability indices of concrete columns. Three sections with rectangular, square and circular shapes are selected. Using the Monte Carlo simulation technique, the statistical parameters for reinforced column resistance are calculated along several load eccentricities using the most recent statistical data available in the literature. The statistical parameters show that the magnitude and the variation of bias factors and the coefficients of variation are not similar for the sections selected. The coefficients of variation of the square and circular sections are greater than that of the rectangular section. The results of reliability analysis indicate the importance of sectional shape, especially at low load eccentricities. In some cases, the effect of cross-sectional shape or reinforcement configuration is found to be more important than the effect of the compressive strength of the concrete. It is recommended to include the shape factor and the reinforcement configuration in the code calibration process for the capacity reduction factors.