CFRP布加固钢箱梁的疲劳试验设计研究

The Research of Fatigue Test Design of Steel Box Girder Reinforced with CFRP Sheet

钢箱梁长期运营后,不可避免地出现疲劳裂纹,疲劳裂纹出现后使得钢箱梁运营具有一定的安全隐患。钢箱梁疲劳裂纹处治包括补焊法、钻孔法和CFRP布加固法等,其中CFRP布加固法充分利用了复合材料的优越性,是一种较为有效的加固方法。根据某节段式钢箱梁构件,选择了CFRP布加固材料,确定了CFRP布加固的5个步骤(表面处理、配胶、涂胶、粘贴CFRP布及锚固),并设计了疲劳加固试验的装置和加载方案。通过对加固构件进行疲劳试验,可研究加固构件的疲劳性能,验证加固构件的加固效果,并对疲劳损伤演化过程进行理论分析。

After a long-term operation of the steel box girder,it inevitably occurs in the appearance of fatigue crack,which may take the operation with a certain security risk.Repairing welding,hole drilling and CFRP reinforcement are the main methods to maintain fatigue crack of the steel box girder.Besides,CFRP reinforcement method makes full use of the advantage of composite materials,and it can be regarded as a more effective maintenance method.According to a segmental steel box girder component,the carbon fiber cloth reinforcement material is selected in five links which contain surface modification,mixed gum,rubber coating,paste CFRP sheets and anchorage,are determined and the devices of fatigue test and the test schemes are designed.Through the fatigue test,it points out the fatigue performance of the strengthened members and the effect of the verified reinforcement,which leads to theoretical analysis of the evolution of fatigue damage.