Academic Journal of Engineering and Technology Science, 2023, 6(5); doi: 10.25236/AJETS.2023.060506.
Xingcan Long, Weifeng Li
Nanjing Vocational Institute of Transport Technology, Nanjing, 211188, China
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.
fatigue performance; fatigue test; finite element analysis; prestressed CFRP plates; reinforcement; fatigue life analysis
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.
 Farghal O A. Fatigue behavior of RC T-beams strengthened in shear with CFRP sheets[J]. Ain Shams Engineering Journal, 2014, 5(3):667-680.
 Meneghetti L C, Garcez M R, Filho L C P D S , et al. Fatigue life of RC beams strengthened with FRP systems[J]. Structural Concrete, 2014, 15(2):219-228.
 Sherif El-Tawil, Cahit Ogunc, Ayman Okeil, et al. Static and fatigue analyses of RC beams strengthened with CFRP laminates [J]. Journal of Composites for Construction, 2001, 5(4):258-267.
 Garden H N, Hollaway L C. An experimental study of the failure modes of reinforced concrete beams strengthened with prestressed carbon composite plates [J]. Composites Part B Engineering, 1998, 29(4): 411-424.
 Ru Haifeng, Zhang Qian, Liang Chunxiang. Experimental study on fatigue stiffness of reinforced concrete beams strengthened with CFRP sheets [J]. Journal of Railway Engineering, 2008, 117(6): 52-55.
 Lin Yudong, Zong Zhouhong, Zhang Meizhen. Experimental study on flexural behavior of RC and PPC beams strengthened with prestressed CFRP Plates [J]. Chinese Journal of highway, 2013, 26(4): 109-118.
 Zhao Shaowei, Su Wei, Zhang Xiaobin.Experimental study on rectangular beams strengthened with prestressed CFRP [J]. Architectural Science, 2017, 33(3): 59-64.
 Peng Hui, Shang Shouping, Zhang Jianren. Study on fatigue behavior of flexural specimens strengthened with prestressed CFRP [J]. Journal of Civil Engineering, 2009, 42(8): 42-49.
 Zhang Xiaobin. Experimental study on fatigue of reinforced concrete beams strengthened with prestressed CFRP Plates [D]. Hebei University of Technology, 2016.
 Deng Lanni, Yu zhaohang, Liao Ling. ANSYS analysis of steel beams strengthened with prestressed CFRP Plates Based on spring rigid domain [J]. Journal of Guangxi University (Natural Science edition), 2014, 39(1): 38-42.
 Cheng Jun. Study on fatigue behavior of concrete continuous beams with externally prestressed CFRP Tendons [D]. Southeast University, 2017.
 Huang Kainan. Numerical simulation of fatigue behavior of RC Beams Strengthened with prestressed CFRP in humid and hot environment [D]. South China University of Technology, 2019.
 Heffernan P J, Erki M A. Fatigue behavior of reinforced concrete beams strengthened with carbon fiber reinforced plastic laminates [J]. Journal of Composites for Construction, 2004, 8(2):132-140.
 Zhang Ke, Ye Lieping, Yue Qingrui. Fatigue life analysis of concrete beams strengthened with prestressed CFRP [J]. Industrial Building, 2008, 38(7):107-112.