Eccentricity-Based Optimization Procedure for Strength Design of RC Sections under Compression and In-Plane Bending Moment
Publication: Journal of Structural Engineering
Volume 140, Issue 1
Abstract
The strength design of reinforced concrete (RC) rectangular sections for combined compression and in-plane bending with two levels of reinforcement is indeterminate: three unknowns are to be solved, but with only two equilibrium equations; an additional condition is necessary to solve the problem. The additional condition leads to the finding of a minimum reinforcement-concrete ratio. This paper proposes a new approach based on the equivalent eccentricity of the applied compressive load. Different domains are reported, each of which is associated with given values of eccentricity and axial load. Analytical expressions for the domain boundaries are established, and a simple procedure is described to outline the conditions corresponding to the optimal reinforcement. The main advantage of this procedure is its simplicity, which allows manual computations. Some examples employing reinforcement sizing diagrams illustrate the validity of this approach.
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Acknowledgments
Part of the present work was financed by the Spanish Ministry of Education. The second author is a Spanish government Ph.D. fellow (FPU grant AP 2010-3707). This support is gratefully acknowledged.
References
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© 2013 American Society of Civil Engineers.
History
Received: Jul 3, 2012
Accepted: Dec 17, 2012
Published online: Dec 19, 2012
Published in print: Jan 1, 2014
Discussion open until: Feb 23, 2014
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