Softening in Reinforced Concrete Beams and Frames
Publication: Journal of Structural Engineering
Volume 113, Issue 12
Abstract
The softening postpeak load‐deflection relation for cracking reinforced concrete beams and frames is analyzed by layered finite elements. Concrete is assumed to exhibit strain softening in both tension and compression, and the steel reinforcement is elastic‐plastic. The bending theory assumptions are used and bond slip of reinforcement is neglected. It is shown that the model can satisfactorily approximate the existing test results for softening beams and frames. At the same time, the constitutive laws with strain softening, including those of continuum damage mechanics, are shown to lead to spurious sensitivity of results to the chosen finite element size, similar to that documented before for other strain‐softening problems. In analogy to the finite element crackband model, this problem can be overcome if the minimum admissible element size is specified as a cross section property; its suitable value appears to be equal to the beam depth.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 113 • Issue 12 • December 1987
Pages: 2333 - 2347
Copyright
Copyright © 1987 ASCE.
History
Published online: Dec 1, 1987
Published in print: Dec 1987
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