Title: Flexural Behavior of Confined Concrete Columns
Author(s): Shamim A. Sheikh and C. C. Yeh
Publication: Journal Proceedings
Appears on pages(s): 389-404
Keywords: axial loads; bending moments, columns (supports); confined concrete; ductility; earthquakes; flexural strength; reinforced concrete; strains; stress block; stress-strain relationships; structural analysis; structural design; tied columns; ties.
An analytical model originally developed for determining the stress-strain curve of confined concrete under concentric compression has been extended to include the effects of strain gradient caused by flexture. The proposed model along with some other models available in the literature is used to predict the behavior of several specimens tested by various researchers including those recently tested at the University of Houston. To simplify the application of the model, a rectangular stress block representing the actual stress-strain curve is proposed. A procedure to determine the dimensions of the stress block is presented. The provisions of Appendix A of the ACI Build-( 318-83) for the confinement steel in ductile frame columns are critically examined.