Shear Strength Components in Reinforced Concrete Members
Publication: Journal of Structural Engineering
Volume 143, Issue 9
Abstract
The shear strength () of reinforced concrete (RC) beams consists of two parts: shear resistance of concrete () and contribution of the transverse reinforcement (). Previous experimental results can only give the total shear strength of a beam. Until now, no existing experimental means could measure the two aforementioned contributions separately with reasonable accuracy during the test of RC beams. This paper reports an experimental method that is able to quantify the two parts in conventional shear tests of RC beams. This was achieved by measuring the strains along the full length of each stirrup in the shear span without disturbing the bond. Thus, the variation in and can be recorded during a beam test. Preliminary tests using this method on particular beams show that not all the shear reinforcement intersecting a critical diagonal crack yields at the onset of shear strength. Both and are not at their maximum values when the shear strength is reached in a beam. The value of is not constant under increasing deformation: it first increases and slightly drops after it reaches a peak, followed by a relatively stable plateau until final shear failure. The variation in with respect to member deformation does not match the predictions of existing models.
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Acknowledgments
The work described in this paper was fully supported by a grant from the National Natural Science Foundation of China (Grant No. 51378449). Undergraduate students Chan Hong Lam, Kwok Ka Chun, and Ho Yuen Ng took part in the experimental tests as part of their final-year projects. Their significant contributions to the work are acknowledged.
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Published In
Journal of Structural Engineering
Volume 143 • Issue 9 • September 2017
Copyright
©2017 American Society of Civil Engineers.
History
Received: Aug 5, 2016
Accepted: Feb 24, 2017
Published online: May 13, 2017
Published in print: Sep 1, 2017
Discussion open until: Oct 13, 2017
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