Title: Trilinear Moment-Curvature Relationship for Reinforced Concrete Beams

Author(s): W. A. M. Alwis

Publication: Structural Journal

Volume: 87

Issue: 3

Appears on pages(s): 276-283

Keywords: beams (supports); bending; computer programs; deflection; cracking (fracturing); deformation; moment-curvature relationship; reinforced concrete; structural analysis; Design

DOI: 10.14359/3060

Date: 5/1/1990

Abstract:
A trilinear moment-curvature curve is constructed by depicting each of uncracked, cracked, and yielded behavior of reinforced concrete beams as linear segments. This curve and Branson's well-known formula for effective stiffness are qualitatively related to each other, and as a result the difference between predictions by the two modules is inherently bounded. Moment-curvature and load-deflection curves derived by Branson's formula and a recent nonlinear model by Bazant and Oh have been compared with those produced by the trilinear model for several example beams. Good agreement is observed among these models. The main advantage of the trilinear model is in computer applications related to analysis and design of reinforced concrete beams and frames.