超声冲击与CFRP复合加固焊接接头疲劳性能研究  

Study on fatigue properties of welded joints strengthened by ultrasonic impact and CFRP

作　　者：郑云[1] 初明进[2] 崔涛 李东东 赵寒川 ZHENG Yun;CHU Mingjin;CUI Tao;LI Dongdong;ZHAO Hanchuan(MCC Construction Research Institute Co.,Ltd,Beijing 100088,China;Beijing Advanced Innovation Center for Future Urban Design,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;China Railway Fifth Survey and Design Institute Group Co.,Ltd,Beijing 102600,China)

机构地区：[1]中冶建筑研究总院有限公司,北京100088 [2]北京建筑大学北京未来城市设计高精尖创新中心,北京100044 [3]中铁第五勘察设计院集团有限公司,北京102600

出　　处：《建筑结构学报》2023年第3期113-121,共9页Journal of Building Structures

基　　金：国家重点研发计划(2016YFC0701303)。

摘　　要：采用超声冲击或粘贴CFRP等方法都可以起到加固焊接接头的效果,但仍难以满足部分接头的加固需求,且对两种方法的加固机理研究不足。为此,提出了采用超声冲击和CFRP复合加固的方法,设计了仅超声冲击处理、仅粘贴CFRP和复合加固方法的试件以及一组未处理的对比试件并进行了疲劳加载试验。结果表明:采用三种处理方法均可以有效提升焊接试件的疲劳强度和疲劳寿命;超声冲击处理后对焊接结构焊缝残余应力的消除作用明显,消除率高达200%以上;采用CFRP加固可以阻碍裂纹扩展,但对焊接缺陷改善效果较小;复合加固方法结合超声加固方法和粘贴CFRP方法的优点,既可以通过超声冲击实现应力重分布,又可以通过CFRP高强度高弹性模量的特点阻止裂纹的产生与发展。Ultrasonic impact treatment(UIT) or CFRP bonding can be used to reinforce welded joints, but it is still difficult to meet the reinforcement requirements of some joints, and the research on the reinforcement mechanism of the two methods is insufficient. For this reason, the composite strengthening method of ultrasonic impact and CFRP reinforcement was proposed. The specimens treated only by ultrasonic impact, pasted only by CFRP and composite strengthening, as well as a group of untreated contrast specimens were designed and fatigue loading tests were carried out. The results show that the three treatment methods can effectively improve the fatigue strength and fatigue life of welded specimens. After ultrasonic impact treatment, the residual stress of welds of welded structure can be eliminated significantly, with the elimination rate of more than 200%. CFRP reinforcement can prevent crack growth, but the improvement effect on welding defects is small. The composite reinforcement method proposed in this paper combines the advantages of ultrasonic reinforcement method and CFRP reinforcement method. It can not only realize stress redistribution through ultrasonic impact, but also prevent the generation and development of cracks due to the high strength and high elastic modulus of CFRP.

关 键 词：焊接钢结构 超声冲击 加固 CFRP 疲劳加载试验 疲劳性能 

分 类 号：TU391.03[建筑科学—结构工程]