Uniaxial confinement model for normal- and high-strength concrete columns

This paper presents a new confinement model based on strain compatibility and transverse force equilibrium. This new approach is capable of predicting the effectiveness of transverse reinforcement, which is key in modeling the behavior of high-strength concrete confined with high-yield-strength steel. The model is validated on test results from more than 200 circular and square large-scale columns tested under slow and fast concentric loading. In addition, results from about 50 square and circular large-scale columns tested under constant axial load and reversed cyclic bending were also used in the assessment of the model adaptability to seismic-type loading. All the predictions are in very good agreement with the experimental results. The model is especially effective in assessing the effectiveness of high-yield-strength steel.