Calculation method of deflection after cracking of RC beams strengthened with CFRP plates under fatigue load

doi:10.19936/j.cnki.2096-8000.20220128.009

Abstract

Abstract: Based on the test data of five specimen beams, the change of mid-span deflection of reinforced concrete beams strengthened with CFRP plates under fatigue load is analyzed. The test results show that under cyclic loading, the bending stiffness of reinforced concrete beams will produce fatigue attenuation, and the sectional curvature will continue to extend, resulting in the continuous increase. The embedded reinforcement method of CFRP plate bottom layer can effectively restrain the decline rate of flexural rigidity of reinforced concrete beams and relieve curvature extension, thus improving their fatigue flexural deformation performance. Finally, by introducing the method of tensile stiffening effect, the calculation model of deflection of beams strengthened with CFRP plates under fatigue load is derived. The calculation results show that the calculated values of the proposed deflection calculation model are in good agreement with the experimental values.

Key words: reinforced concrete beam, CFRP, fatigue load, deflection

CLC Number:

TB332

DENG Lang-ni, LEI Li-zhen, XIE Hong, ZHOU Zheng, LIAO Ling. Calculation method of deflection after cracking of RC beams strengthened with CFRP plates under fatigue load[J]. COMPOSITES SCIENCE AND ENGINEERING, 2022, 0(1): 62-67.

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