Fatigue performance and life prediction of CFRP plate in the RC bridge roof reinforcement

Abstract This paper investigated the fatigue properties and theoretical research on Carbon-Fiber-Reinforced Polymer (CFRP) RC bridge roof with new deck-pavement material. Two deck pavement schemes of CFRP-reinforced specimens were designed and tested. Four-point flexural fatigue tests were carried out on the specimens. The fatigue crack propagation, the deflection development and the CFRP strain under bridge fatigue load were researched. The test results show that the CFRP plate-reinforced specimens crack resistance performance can be improved and can bear the fatigue test load of two million times. Combined with the characteristics of the crack growth rate and fatigue damage accumulation of CFRP plate-reinforced bridge roof specimens, the fatigue life prediction analytical model for CFRP plate reinforced RC bridge roof was obtained. The fatigue life prediction model agrees well with the experimental results. The model proposed in this paper could be applied to predict the fatigue life of the CFRP plate-reinforced RC bridge roofs.

摘要 本研究针对采用新型桥面铺装材料的碳纤维增强聚合物（Carbon-Fiber-Reinforced Polymer，CFRP）加固钢筋混凝土（Reinforced Concrete，RC）桥梁顶板的疲劳性能开展了试验与理论研究。研究设计并完成了两类CFRP加固试件的桥面铺装方案，对试件实施了四点弯曲疲劳试验，探究了桥梁疲劳荷载作用下的疲劳裂纹扩展规律、挠度演化特性及CFRP应变响应。试验结果表明，CFRP板加固试件的抗裂性能得到显著提升，且可承受200万次循环的疲劳试验荷载。结合CFRP板加固桥梁顶板试件的裂纹扩展速率与疲劳损伤累积特征，本研究构建了CFRP加固钢筋混凝土桥梁顶板的疲劳寿命预测解析模型，该模型与试验结果吻合良好。本文提出的模型可用于预测CFRP加固钢筋混凝土桥梁顶板的疲劳寿命。