STRENGTH AND DUCTILITY ENHANCEMENT OF REINFORCED HSC COLUMNS CONFINED WITH HIGH-STRENGTH TRANSVERSE STEEL

Abstract

High-strength steel as transverse reinforcement is seldom used for confining steel in high-strength concrete columns. The behavior of structural components as a consequence of the use of a combination of high-strength concrete and steel is still not well known. To obtain an accurateductility of high-strength concrete confined columns, it requires an analytical stress-strain model of confined concrete which is capable of describing an actual strength and ductility behavior. In this paper, an analytical stress-strain relationship for confined high-strength concrete is proposed. The model is found to provide a reasonably good prediction of the available experimental data of circular and square high-strength concrete column specimens confined by high-strength transverse steel with various configurations. The proposed model is based on the extensively obtained data from tests of column specimens subjected to concentric compression loading. The model can also be used for concrete columns confined by spirals or circular hoops, rectilinear hoops, crossties, and combinations of these reinforcements.