FRP补强疲劳损伤钢结构裂纹扩展研究

Fatigue Damaged Crack Growth of Steel Structure Strengthened With FRP Patches

钢结构在服役过程中,因超载、疲劳等原因会引起损伤累积,极大地影响了结构的安全使用。对纤维增强复合材料(FRP)补强钢结构张开型裂纹疲劳扩展进行了实验研究。比较了不同的钢结构表面处理方式对FRP与钢结构粘接接头剪切强度的影响,根据剪切强度选择最佳表面处理工艺。对FRP补强后钢结构试样进行疲劳实验,与未补强试样的结果加以对比。结果表明,用FRP增强后钢结构FRP增强区疲劳裂纹扩展速率得到抑制、疲劳循环次数得到了提高。

The cumulative damage of the steel structure occurred by overload,fatigue and other reasons in service may deteriorate the safety of the structure seriously.The edge-opened fatigue crack propagation of steel structure strengthened with fiber reinforced plastic(FRP) composite is studied experimentally.The influence of surface preparation of steel specimen on the shearing strength of the bonded joint of steel structure and the FRP patches is investigated,and the optimum preparing technique is decided.The fatigue tests for steel structure strengthened with FRP patches are carried out,the results are compared with that of steel structure without strengthening.The experiments results indicate that after strengthened with FRP patches,the propagation rate of fatigue crack is lowered,and the fatigue cycle number is increased.