Size Effect on Shear Strength of Reinforced Concrete: Is CSCT or MCFT a Viable Alternative to Energy-Based Design Code?
Publication: Journal of Engineering Mechanics
Volume 146, Issue 10
Abstract
After sketching the history of the size effect models for the shear strength of reinforced concrete (RC) in design codes, the energy-based size effect law (SEL), recently incorporated into the American Concrete Institute (ACI) design code articles for beam shear and slab punching, is briefly discussed. A general derivation of the SEL based only on the first principles involving energy conservation and dimensional analysis (or laws of similitude) is presented. Attention is then focused on recent articles that present a severe critique of the SEL and various arguments in support of the Muttoni et al.’s critical shear crack theory (CSCT)—an update of the Collins et al.’s modified compression field theory (MCFT)—that some researchers propose to be introduced into the fib Model Code and the Eurocode as an alternative to the SEL. In a point-by-point analysis, it is shown that this critique and these arguments are incorrect and baseless. It is hoped that the present clarification would lead to progress in design codes, enhancing the safety and efficiency of RC structures.
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Data Availability Statement
Some or all data, models, or code generated or used during the study are available in a repository online in accordance with funder data retention policies. Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
Partial preliminary funding under National Science Foundation (NSF) Grant No. CMMI-2029641 to Northwestern University is gratefully acknowledged.
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Published In
Journal of Engineering Mechanics
Volume 146 • Issue 10 • October 2020
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Feb 13, 2020
Accepted: Mar 19, 2020
Published online: Jul 17, 2020
Published in print: Oct 1, 2020
Discussion open until: Dec 17, 2020
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