恶劣环境影响下FRP加固锈蚀混凝土梁受力性能研究

Reiforcement corrosion in reinforced concrete structures has become the main threaten to the durablility of concrete structures. Fiber composite material (FRP) has proved great potential in structure reinforcement. Based on research results of FRP reinforced concrete structures and concrete durability, the failure mechanism of FRP reinforced corroded concrete's interfacial bond and adhesion degradation law as well as experimental study and finite element analysis are refered to in this project to study the mechanical behavior of FRP reinforced corroded concrete beams under the influence of artificial seawater. In this project, interface bonding performance tests of FRP reinforced corroded concrete are carried out to reveal the stress degradation law of interfacial bond between diffrent materials and establish the interfacial bond-slip constitutive relation of FRP reinforced materials, corroded reinforcement and concrete, taking environmental factors into consideration. Refering to experiment and parameter analysis results, the bending and shear failure mechanism of FRP reinforced corroded concrete beams are studied, deformation coordination relationships between reinforced FRP, corroded steel bars and concrete are built and shear calculation models are established. Calculation method of bearing capacity that is reasonable and convenient for engineering application is put forward and relevant construction measures are improved. This research has great theoretical and engineering significance on improving the reinforcing and repairing method of corroded concrete structures.

钢筋混凝土结构中钢筋的锈蚀引已成为威胁混凝土结构耐久性的主要灾害，纤维复合材料（FRP）已被证明在结构加固领域有着巨大的潜力。本项目基于FRP加固混凝土结构及混凝土结构耐久性的研究成果，从FRP加固锈蚀混凝土界面粘结的破坏机理与粘脱退化规律入手，结合试验研究和数值模拟分析，研究人工海水环境影响下FRP加固锈蚀混凝土梁的受力性能。本项目拟进行FRP加固锈蚀混凝土界面粘结性能试验，揭示不同材料之间的界面粘结应力退化规律，建立考虑环境因素影响的FRP加固材料、锈蚀钢筋与混凝土界面粘结滑移本构关系；结合试验和多参数分析结果，探索FRP加固锈蚀混凝土梁的抗弯、抗剪破坏机理，建立加固后的FRP、锈蚀钢筋与混凝土之间的变形协调关系及抗剪计算模型；提出合理且便于工程应用的承载力计算方法，完善相关的构造措施。本研究对完善锈蚀混凝土结构加固维修方法具有重要的理论和工程意义。

钢筋混凝土结构中钢筋的锈蚀和构件损伤引已成为威胁混凝土结构耐久性的主要灾害，FRP已被证明在结构加固领域有着巨大的潜力。本项目基于FRP加固混凝土结构及混凝土结构耐久性的研究成果，从FRP加固锈蚀混凝土界面粘结的破坏机理与粘脱退化规律入手，通过大量的试验研究和数值模拟分析，研究了FRP加固既有损伤钢筋混凝土构件的受力性能。本项目进行53个FRP加固锈蚀混凝土界面粘结性能试验，揭示不同材料之间的界面粘结应力退化规律，建立考虑环境因素影响的FRP加固材料、锈蚀钢筋与混凝土界面粘结滑移本构关系，并与已有的研究进行了对比，验证了项目组提出的本构关系的精确性；进行14个既有损伤混凝土构件自身及其加固后的受力性能试验研究，探索了FRP加固锈蚀钢筋混凝土构件的破坏机理，提出了采用折减系数考虑既有混凝土构件损伤的承载力计算方法，并完善相关的构造措施。