Shear Deformations of RC Beams under Service Loads
Publication: Journal of Structural Engineering
Volume 143, Issue 1
Abstract
Shear deformations of reinforced concrete (RC) beams are not negligible after shear cracking. However, unlike the well-established procedure for calculating bending deformations of cracked beams, the calculation of shear deformations is still ignored in codes of practice due to a lack of practical models. This study aims to develop a practical approach for estimating instantaneous shear deformations of RC beams under service loads. Based on the truss analogy, an explicit equation for evaluating the yield shear stiffness of fully diagonally cracked beams is derived. It is discovered that the shear retention factor (ratio of the yield shear stiffness to the initial elastic shear stiffness) is approximately the cubic root of the shear-reinforcement ratio. An analytical approach for evaluating the degradation of effective shear stiffness and the development of shear deformation is proposed. Two restrained I-beams with thin webs are tested. This test and shear-deformation tests available in the literature are used to validate the analytical approach.
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Acknowledgments
This study was supported by National Natural Science Foundation of China (51408116 and 51278120), Natural Science Foundation of Jiangsu Province (BK20140630), Priority Academic Program Development of Jiangsu Higher Education Institutions, and Transportation Science and Technology Project of Jiangsu Province (2014Y01). Their financial support is greatly appreciated. The authors also thank Kaiqi Zheng from Southeast University, Nanjing, China, for his valuable suggestions.
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Published In
Journal of Structural Engineering
Volume 143 • Issue 1 • January 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Jul 26, 2015
Accepted: Jul 14, 2016
Published online: Aug 16, 2016
Published in print: Jan 1, 2017
Discussion open until: Jan 16, 2017
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