In order to study the performance of bridges reinforced by prestressed CFRP plates under vehicle load, four reinforced concrete (RC) beams strengthened with prestressed CFRP plates and one unreinforced beam were designed. The reinforced beams adopted two typical prestressed anchor systems. The failure mode, bearing capacity, stiffness degradation and strain change law of the reinforced beam under static and variable amplitude fatigue cyclic loading were investigated through static bearing capacity test and fatigue performance test. A nonlinear finite element model of the test beam was established to simulate the static load test process. Research indicates: Compared with the unreinforced specimens, the cracking load of the RC specimens strengthened with the prestressed CFRP plate is increased by 60%, and the ultimate load is increased by 32% and 50%. The prestressed CFRP plate and the concrete at the bottom of the beam show good synergistic deformation performance. Under the action of variable amplitude fatigue load, the bending stiffness of the strengthened beam generally decreases linearly. The existence of prestress makes the stress distribution of the tension main bar more uniform and improves the fatigue resistance of the concrete beam. Therefore, the prestressed CFRP plate has a significant effect on strengthening reinforced concrete beams. The variable amplitude fatigue load is converted into equivalent constant amplitude fatigue load for life analysis. The fatigue life of the reinforced beam is 8 million times and 12 million times respectively. The safety performance of the two anchoring systems meets the normal use requirements of the structure.

Xingcan Long, Weifeng Li. Static and Fatigue Properties of RC Beams Strengthened with Prestressed CFRP Plates. Academic Journal of Engineering and Technology Science (2023) Vol. 6, Issue 5: 30-40. https://doi.org/10.25236/AJETS.2023.060506.

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