Abstract
This paper presents a detailed study on flexural strengthening of RC beams with externally bonded technique using carbon fiber-reinforced polymer laminate. The different strengthening methods used in this work are externally bonded laminate (EBL), externally bonded laminate with anchorage (EBLA), and externally bonded prestressed laminate with anchorage (EBPLA). All the beams were designed for under-reinforced condition. Totally, eight beams were cast; out of this, two beams were control beams. Strengthened beams were divided into three sets (EBL, EBLA, and EBPLA) of two beams each. The work was mainly concentrated on the improvement of ultimate load carrying capacity by delaying the debonding failure. The experimentation was done using two-point loading condition. The result shows that the ultimate load for all the strengthened beams was improved when compared to control beams. The beams strengthened with EBPLA technique show maximum increase in ultimate load, i.e., 73.91% with reference to control beams. All the control and strengthened beams satisfy the serviceability requirement. The comparative study was done on the theoretical and experimental results to check the efficiency of different strengthening codes.
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Acknowledgements
The experimental programme was conducted at Structural Engineering Laboratory of Civil Engineering Department, Bangalore Institute of Technology, Bangalore. We convey our sincere thanks to R & M International Pvt. Ltd., for sponsoring the complete prestressing setup and also laboratory staff members for their assistance throughout the Experimental Program.
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Jeevan, N., Reddy, H.N.J. & Prabhakara, R. Flexural strengthening of RC beams with externally bonded (EB) techniques using prestressed and non-prestressed CFRP laminate. Asian J Civ Eng 19, 893–912 (2018). https://doi.org/10.1007/s42107-018-0071-y
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DOI: https://doi.org/10.1007/s42107-018-0071-y