纤维增强复合筋超静定混凝土梁的抗弯性能

Flexural Behaviour of Indeterminate Concrete Beams Reinforced with FRP Bars

采用改进的局部变形模型,对纤维增强复合筋超静定混凝土梁的抗弯性能进行研究。首先提出一个模型并将其性能与由FRP筋加固的简支及连续混凝土梁的试验结果进行对比。然后将模型应用到FRP筋连续梁中来预测弯矩分布,以及弯曲裂缝的形态,包括裂缝间距和裂缝宽度。尤其是该模型具有在梁中的高应变区确定变形的能力。基于理论分析结果,通过比较FRP筋增强的梁与普通钢筋混凝土梁,阐述了混凝土梁的延性和超载性能。所有的结果和相关解释均取决于某些特定假设和模型中的输入参数,尤其取决于FRP筋和混凝土之间的粘结性能。

This paper presents a theoretical study of the flexural behaviour of indeterminate concrete beams reinforced with fibre reinforced polymer （FRP） bars using a local deformation model developed by the authors. The model is firstly presented and its performance compared with tests on simply supported and continuous concrete beams reinforced with FRP bars. A detailed theoretical investigation is then conducted by applying the model to continuous beams reinforced with FRP bars in order to predict the bending moment distribution, as well as the progressive formation of flexural cracks and associated crack spacings and crack widths. Of particular interest is the ability of the model to determine the deformations in highly stressed regions in the beam. Based on the theoretical results, comments are made as to the ductility and overload behaviour of concrete beams reinforced with FRP bars in comparison to Concrete beams reinforced with steel bars. All results and associated comments are dependent on certain assumptions and are dependent on the input parameters used in the model. The results are found to be particularly dependent on the bond characteristics between the FRP bar and surrounding concrete.