FLEXURAL BEHAVIOR OF REINFORCED CONCRETE BEAMS STRENGTHENED WITH EXTERNAL POSTTENSION GFRP REBARS
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Abstract
The method of reinforced concrete structures with external posttension has proven to be highly effective. In modern times, fiber-reinforced polymer has replaced traditional prestressed concrete steel strand, addressing concerns related to corrosion and durability. This research aimed to examine the flexural behavior of reinforced concrete beams strengthened using external posttension glass fiber-reinforced polymer tendons. The research focused on determining the appropriate percentage ratio for prestressing. Three beam specimens were tested: one without external prestressing (control beam) and two strengthened using external prestressing glass fiber-reinforced polymer tendons. The concrete beams measured 150 300 2500 millimeter and were prestressed at 20% and 40% of the ultimate tensile stress of GFRP rebars. Test behavior includes Load–deflection curves, crack patterns, and the mode of failure. The results showed that the strengthened beams increased their flexural strength by 41%, and the external prestressing system raised the force that caused the first crack by 86%.
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This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
The published articles are copyright of the Engineering Journal of Research and Development, The Engineering Institute of Thailand Under H.M. The King's Patronage (EIT).
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