Theorems for Flexural Design of RC Members
Publication: Journal of Structural Engineering
Volume 142, Issue 5
Abstract
Three theorems of the flexural theory for RC members are derived to identify two critical points on a moment–curvature curve: (1) the onset of flexural strength and (2) the onset of the so-called true ultimate curvature. The true ultimate curvature is reached at the exact moment when a RC member loses its integrity. The first two theorems concern the first point and the third relates to the second. Exact analytical solutions of the extreme concrete strain for these two critical points are derived for general RC members, including underreinforced and overreinforced beams and RC columns. The solutions can be used to calculate the exact strength and the corresponding deformation and to evaluate concrete damage at the onset of the two critical points. The analytical results can also be used in practice for the design of RC members, which is particularly useful when precise evaluations of flexural strength and damage conditions at the onset of maximum moment or ultimate displacement are required.
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Acknowledgments
The work that is described in this paper was supported by grants from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project CityU 124113) and the National Natural Science Foundation of China (Grant 51378449).
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Published In
Journal of Structural Engineering
Volume 142 • Issue 5 • May 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Apr 3, 2015
Accepted: Oct 14, 2015
Published online: Dec 18, 2015
Published in print: May 1, 2016
Discussion open until: May 18, 2016
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