COMPLETE STRESS-STRAIN CURVE OF CONCRETE AND ITS EFFECT ON DUCTILITY OF REINFORCED CONCRETE MEMBERS

A relatively simple experimental technique was developed to obtain the entire stress-strain curve of concrete. The experimental curves were obtained for normal weight concrete of compressive strengths up to 11,000 psi and lightweight concrete of strengths up to 8,000 psi. An analytic expression for the stress-strain curve is proposed. The expression has four constants which depend on the properties of both the ascending and the descending portions of the curve. A computerized nonlinear analysis program was developed to predict the structural response of reinforced concrete on the ultimate strength parameters of the concrete compressive zone.