中文摘要：

FRP筋混凝土受弯构件的破坏模式包括混凝土压碎和FRP筋断裂两种模式，FRP筋混凝土受弯构件双筋截面承载力应根据破坏模式进行计算。现有设计规范的截面承载力计算方法均未考虑受压区配置FRP筋的作用。为此，根据混凝土本构模型，利用受压区混凝土抛物线一矩形应力图，推导了FRP筋混凝土受弯构件双筋矩形截面的抗弯承载力计算公式，给出了FRP筋拉断破坏时不需迭代求解的简化计算公式，并将单筋方法计算结果、双筋方法计算结果与其他文献给出的试验结果进行了对比。结果表明，对于混凝土压碎破坏模式，当配筋率较大时，按单筋方法计算的结果与试验值之间误差较大，应考虑受压区FRP筋的贡献。用已有文献提供的6个双筋截面梁的抗弯承载力试验值验证了建议方法预测值的准确性，该计算方法能够满足FRP筋混凝土受弯构件双筋截面承载力的设计要求。

英文摘要：

The failure modes of concrete members reinforced with fiber-reinforced polymer （FRP） bars include concrete crushing and FRP rupture. The flexural capacity of FRP reinforced concrete sections should be calculated according to the failure mode of FRP RC members. The existing guidelines for FRP RC are not given the section bearing capacity calculation method with FRP bars in the compression zone. Consequently, this paper proposes a general methodology for determining the moment capacity of FRP RC sections by utilizing the general parabolic-rectangular diagram for concrete in compression according to the GBS0010 model. To avoid the iterative process, a simplified calculation formula of the moment capacity can be adopted when FRP rupture governs the design. The results from other literatures, the results of the calculation of the single reinforcement method and the results of the two reinforcement methods are compared. The results show that the error between the calculated results and the experimental values is large for the concrete crushing failure mode when the reinforcement ratio is large, and the contribution of FRP bars in the compression zone should be considered. The accuracy of the proposed design method has been verified by comparing the predictions with the experimental results of 6 beams,which are available in the published literature. The design method can be used to calculate the flexural capacity of FRP RC section.