Title: Improvement of Flexural Behavior of Reinforced Concrete Sections by Combined Use of Different Grade Longitudinal Bars
Author(s): F. Watanabe and K. Ohsumi
Publication: Symposium Paper
Appears on pages(s): 927-940
Keywords: axial loads; columns (supports); cyclic loads; deformation; ductility; flexural tests; loading tests; moment-curvature relationship; reinforced concrete; reinforcing steels; Design
A new method to enhance the moment-curvature relations of reinforced concrete sections in post-yield range of deformation was developed. The point of the idea is to introduce the sequential yielding of different grade longitudinal bars in a section with the progress of section curvature. The section then does not have any negative stiffness up to the yielding of highest grade bars and results in very ductile behavior. To confirm the advantages of the new method, flexural analyses and loading tests were carried out on reinforced concrete columns with different grade longitudinal bars. The results of theoretical calculations and loading tests indicated that the combined use of different grade longitudinal bars can considerably improve the flexural behavior of reinforced concrete sections.