中、欧规范下钢桥面板纵肋与顶板焊接节点疲劳性能评价

Fatigue Performance Evaluation of Longitudinal Rib and Deck Welded Joints of Steel Bridge Deckunder Chinese and European Codes

纵肋与顶板焊接细节是钢桥面板重要的疲劳易损细节,目前研究大多通过S-N曲线对该细节进行疲劳评价,未能考虑初始缺陷影响。文中基于线弹性断裂力学理论,利用ANSYS有限元软件,综合对比了中、欧规范下纵肋与顶板焊接细节疲劳性能。研究表明,中、欧规范2种疲劳工况下,纵肋与顶板焊接细节疲劳裂纹均以张开型裂纹为主,欧洲规范下裂纹扩展速率整体快于国内规范,由Paris公式得到国内规范疲劳寿命为1090万次,欧洲规范疲劳寿命为543万次。

The longitudinal rib and deck welded joints are important fatigue vulnerable details of steel bridge deck.At present,most of the researches use S-N curve to evaluate the fatigue performance of these details,and the effect of initial defects is not considered.In this paper,based on the theory of linear elastic fracture mechanics,ANSYS finite element software is used to comprehensively compare the fatigue properties of the longitudinal ribs and deck welded joints under Chinese and European codes.The research shows that under the two types of fatigue vehicle operating conditions in Chinese and European codes,the fatigue cracks in the longitudinal rib and deck welded joints are mainly opening mode cracks.The crack growth rate under European code is faster than that in Chinese code.According to the Paris formula,the fatigue life under Chinese and European code is 10.9 million timesand 5.43 million times,respectively.