CFRP粘接加固正交异性钢桥面板界面破坏机理研究

Mechanism of Interface Failure of Orthotropic Steel Bridge Deck Strengthened by CFRP Bonding

对碳纤维增强复合材料(Carbon Fiber Reinforced Polymer,CFRP)粘接加固正交异性钢桥面板界面性能进行了研究。采用考虑损伤因子的疲劳内聚力模型建立CFRP粘接加固正交异性钢桥面板有限元模型,采用二次名义应力准则判断界面损伤起始位置,根据幂法准则判断界面损伤破坏。以安庆长江公路大桥正交异性钢桥面板为研究背景,通过有限元模拟研究CFRP粘接加固正交异性钢桥面板界面破坏情况和应力分布。结果表明:CFRP粘接加固正交异性钢桥面板在盖板-U肋焊缝处首先发生界面破坏,随着荷载循环次数的增大,胶层破坏逐渐向纵肋和桥面板两端延伸,且界面破坏经过弹性阶段、软化阶段和界面破坏阶段3个阶段。

In order to study the interface performance of carbon fiber reinforced polymer(CFRP)bonded orthotropic steel bridge decks,this study used a fatigue cohesion model considering damage factors to establish a finite element model of CFRP bonded orthotropic steel bridge decks.Through finite element simulation,the interface failure analysis and stress distribution of CFRP bonded orthotropic steel bridge decks were studied.Research has shown that interface failure first occurs at the joint between the cover plate and the U-rib of an orthotropic steel bridge deck strengthened with CFRP bonding.As the number of load cycles increases,the adhesive layer failure gradually extends towards the longitudinal rib and both ends of the bridge deck.The interface failure goes through three stages:elastic stage,softening stage,and interface failure stage.