The cracking moment of concrete beams reinforced with glass fiber-reinforced polymer (GFRP) bars is an important index for measuring the anti-cracking capacity, and which is also an important parameter to calculate the crack width, deflection and mechanical properties of concrete beams reinforced with GFRP bars. Based on the calculation method for cracking moment of RC beams, combined with tensile strain relationship of concrete, the method of calculating the cracking moment of concrete beam reinforced with GFRP bars which is connected with the calculation method of cracking moment of reinforced concrete beam is deduced. To study the influence rule of reinforcement ratio of GFRP bars and the concrete strength on cracking moment, the experiments on flexural capacity of 14 concrete beams reinforced with GFRP bars were carried out. The accuracy of the proposed calculation method has been verified by comparing the predictions with the experimental results. The results show that the design method can be used to calculate the cracking moment of GFRP RC double reinforcement section beams.

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