为了解决循环荷载作用下纤维增强复合塑料(FRP)加固钢筋砼桥梁构件疲劳性能问题,根据FRP抗弯加固钢筋混凝土梁的疲劳试验资料,建立FRP加固梁式构件疲劳寿命预测模型、钢筋峰值应变累积并模型和构件挠度累积模型,并与既有相关模型的预测精度进行比较.研究结果表明:以钢筋峰值应变和挠度作为基于变形的疲劳性能指标,不仅可以与传统的基于应力的指标相似的精度预测FRP加固构件承受的循环荷载次数,还可与结构监测系统信息结合,实现疲劳失效预警.
In order to figure out the fatigue behavior of fiber-reinforced polymers(FRP)strengthened reinforce concrete bridge girders under the cyclic loading,the fatigue life prediction model,the steel peak strain accumulation model,and the member deflection increment model for reinforced concrete(RC)girder strengthened with FRP were established on basis of the experimental data of flexural strengthening.The accuracies of these models were compared with those of the present available models.The results indicate that the steel peak strain accumulation model and deflection increment model can be used for fatigue life prediction with similar accuracy as the traditional stress based index.Furthermore,the above mentioned deformation based models are recommended for fatigue failure alert as the strain and deflection can be easily achieved by a structure monitoring system.