Theoretical stress-strain model for concrete in steel-reinforced concrete columns

Abstract

This paper investigated the confinement mechanism of steel-confined concrete in steel-reinforced concrete (SRC) columns. Six axially loaded SRC-core columns were tested and the corresponding structural performance data were collected and assessed. Considering the confinement mechanism of both steel-confined and hoop-confined concrete, the concrete in the SRC columns was divided into four regions: highly steel-confined concrete (HSCC), partially steel-confined concrete (PSCC), partially confined concrete (PCC), and unconfined concrete (UCC). Based on Mander’s model, a theoretical stress–strain model for each concrete region was proposed and implemented in an analytical model to predict the mechanical behaviors of axially loaded SRC columns from the results of the tests described in this paper and of previous tests; satisfactory agreement was observed.