BEHAVIOR OF WIDE-FLANGE STEEL BEAMS STRENGTHENED WITH CFRP PLATES UNDER BENDING TEST
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Abstract
This study investigates behavior of wide-flange steel beams strengthened with CFRP plates under bending test. A total of six beam specimens were tested under four-point bending. The span length of the test beams was 1800 mm. The variables considered in this study included the number of CFRP layers, the use of end anchorage for the CFRP plates, and the installation of steel stiffeners to control the failure modes of the beams. The test results show that strengthening the bottom flange of the beam with CFRP plates significantly increases the load-carrying capacity and effectively reduces beam deflection in the elastic range. However, the use of CFRP plates alone may lead to local buckling of the top flange or the web before the beam reaches the plastic deformation stage. The installation of steel stiffeners can reduce local buckling and further improve the load-carrying capacity. Meanwhile, the use of end anchorage for the CFRP plates helps prevent premature debonding, resulting in significant improvements in both the load-carrying capacity and the ductility of the beams.
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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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