Shear Span–Depth Ratio Effect on Behavior of RC Beam Shear Strengthened with Full-Wrapping FRP Strip
Publication: Journal of Composites for Construction
Volume 20, Issue 3
Abstract
Shear span-to-effective depth ratio () is known to affect the shear behavior of RC members. However, this effect has not been appropriately addressed in existing design guidelines for the fiber-reinforced polymer (FRP) strengthening of RC structures. This paper focuses on the effect of on the behaviors of RC beams shear strengthened with full-wrapping FRP strips. A total of six strengthened beams and six normal beams are tested, with ratios ranging from 1.0 to 3.5. The experimental results indicate that the FRP shear contribution increases initially with the ratio, but decreases when the ratio is beyond 2.5. The FRP strain along the critical shear crack distributes in different manners for different ratios. The authors’ experimental results and the test results from the literature are compared with predictions from available design guidelines. Although some recent design guidelines always provide a safe value, it can be overconservative. Conversely, other recent design guidelines may overestimate the shear-strengthening effectiveness at low span/depth ratios so they have to be used with caution.
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Acknowledgments
The financial support of this study by the National Natural Science Foundation of China (Grant No. 51278305) and the Ministry of Science and Technology for the 973-project (No. 2011CB013604) are gratefully acknowledged. The authors would like to acknowledge the assistance from the staff of the Concrete and Structure Laboratory at the Hong Kong University of Science and Technology. Mr. Hui Song, Miss Xiaoli Ren, and Mr. Yong Yang are also gratefully acknowledged for their contributions in collecting lots of experimental results from the literature and drawing some of the figures for the paper.
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Published In
Journal of Composites for Construction
Volume 20 • Issue 3 • June 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Jan 15, 2015
Accepted: Jul 31, 2015
Published online: Oct 15, 2015
Discussion open until: Mar 15, 2016
Published in print: Jun 1, 2016
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