基于PDEM的正交异性钢桥面板焊接节点时变疲劳可靠度评估  

Time-dependent fatigue reliability assessment for welded joints of orthotropic steel bridge decks based on the probability density evolution method

作　　者：郝静 卢海林 陈龙[3] HAO Jing;LU Hailin;CHEN Long(School of Civil Engineering and Architecture,Wuhan Institute of Technology,Wuhan 430074,China;Hubei Provincial Engineering Research Center for Green Civil Engineering Materials and Structures,Wuhan Institute of Technology,Wuhan 430074,China;China Railway 11th Bureau Group No.1 Engineering Co.,Ltd.,Xiangyang 441104,China)

机构地区：[1]武汉工程大学土木工程与建筑学院,武汉430074 [2]武汉工程大学绿色土木工程材料与结构湖北省工程研究中心,武汉430074 [3]中铁十一局集团第一工程有限公司,湖北襄阳441104

出　　处：《振动与冲击》2024年第18期87-95,共9页Journal of Vibration and Shock

基　　金：湖北省高等学校优秀中青年科技创新团队计划(T2020010)。

摘　　要：提出了基于概率密度演化方法的正交异性钢桥面板焊接节点时变疲劳可靠度评估方法,并以润扬大桥顶板-U肋焊接节点为对象开展应用研究。首先,基于S-N曲线和Miner准则,构建了可同时考虑疲劳性能退化和荷载效应增长的钢桥面板焊接节点疲劳极限状态函数,并导出其概率密度演化方程。然后,采用有限差分法求解该方程,据此得到概率密度演化曲面,进而建立其时变疲劳可靠度评估方法。最后,通过工程实例验证了所提方法的可行性和准确性,并探讨了疲劳性能退化和荷载效应增长对该节点时变疲劳可靠度的影响规律。研究表明:与Monte Carlo法相比,该方法不仅精确高效,还能捕捉概率密度演化信息;疲劳性能退化和荷载效应增长会显著影响钢桥面板焊接节点的疲劳寿命。A time-dependent fatigue reliability assessment method based on the probability density evolution method was proposed for orthotropic steel deck welded joints,and applied in the example of a welded rib-to-deck joint in the Runyang Bridge.Firstly,based on the S-N curve and Miner’s criterion,the fatigue limit state function of the welded joint in steel deck with consideration of the degradation of the fatigue behavior and growth of loading effect was established,and the probability density evolution equation was derived.Then,the equation was solved by the finite difference method to obtain the corresponding probability density evolution surface,and then a time-dependent fatigue reliability assessment method for that was presented.Finally,the feasibility and accuracy of the proposed method was verified through the engineering example,and the influences of degradation of the fatigue behavior and growth of loading effect on the time-dependent fatigue reliability of the welded joint were discussed.The results reveal that the proposed method is of preferable computational precision,efficiency,and can capture the probability density evolution information by comparison with the Monte Carlo method.Degradation of the fatigue behavior and growth of loading effect significantly affect the fatigue life of the welded joints in orthotropic steel decks.

关 键 词：时变疲劳可靠度 正交异性钢桥面板 概率密度演化方法 疲劳性能退化 荷载效应增长 

分 类 号：U448.36[建筑科学—桥梁与隧道工程] U441.4[交通运输工程—道路与铁道工程]