Elastic Design of Slender High-Strength RC Circular Columns Confined with External Tensioned Steel Straps

This article proposes a design approach to calculate the capacity of slender high-strength concrete (HSC) columns confined with a cost-effective Steel Strapping Tensioning Technique (SSTT). The approach is based on results from segmental analyses of slender SSTT-confined circular columns subjected to eccentric loads. A capacity reduction factor analogue to that proposed by Kwak and Kim (2004) accounts for the effect of slenderness in design. P-M interaction diagrams computed using rigorous nonlinear P-∆ analyses are compared to those calculated by the proposed approach to assess its accuracy. The results indicate that the proposed approach predicts conservatively the ultimate capacity of slender HSC circular columns confined using the SSTT, and therefore it can be used in the design of modern reinforced concrete (RC) structures.