基于FEA与应力在线监测的RTG钢结构疲劳寿命预测  

Fatigue life prediction of RTG steel structures based on FEA and stress online monitoring

作　　者：徐彬 王腾 林明辉 刘媛媛 李芳 XU Bin;WANG Teng;LIN Minghui;LIU Yuanyuan;LI Fang(School of Mechanical Engineering,Shanghai Institute of Technology,Shanghai 201418,China;Center of Engineering Training,Shanghai Institute of Technology,Shanghai 201418,China)

机构地区：[1]上海应用技术大学机械工程学院,上海201418 [2]上海应用技术大学工程训练中心,上海201418

出　　处：《应用技术学报》2024年第3期316-320,共5页Journal of Technology

基　　金：上海市“科技创新行动计划”生物医药科技支撑专项(20S31905500);上海应用技术大学中青年教师科技人才发展基金(ZQ2020-23);上海应用技术大学引进人才科研启动项目(YJ2021-45)资助。

摘　　要：疲劳是轮胎式集装箱门式起重机(RTG)钢结构发生破坏的主要因素之一。针对RTG的工作特点和动力学特性,提出一种适用于RTG钢结构的疲劳寿命预测方法。采用有限元分析(FEA)获取其自重应力,与应力在线监测获取的外载荷应力进行线性叠加,获得其工作过程中的完整的应力谱样本;采用雨流计数法获取S-N特征曲线,基于Miner法则进行时域疲劳寿命预测;采用Welch函数进行快速傅里叶变换,将应力谱样本转换为频域信号,基于Dirlik、ZB模型进行频域疲劳寿命预测。分析结果表明,3种模型的相对误差非常小,时域方法需要大量的应力谱样本,频域方法计算效率更高,3种模型均可应用于工程实际。Fatigue is one of the primary factors responsible for the failure of the steel structure of the rubber tire container gantry crane(RTG).A fatigue life prediction method was proposed based on the working conditions and dynamic properties of RTG.Firstly,finite element analysis(FEA)was adopted to compute stress of gravity,and the entire stress spectrum sample was approached through linear superposition with external load stress obtained from stress online monitoring.Then,rainflow counting method was employed to obtain S-N curve,and time-domain fatigue life prediction was performed based on Miner rules fatigue.Next,the stress spectrum samples were converted into frequency domain signals through the Welch function for fast Fourier transform,and then the fatigue life prediction in frequency domain was conducted based on Dirlik and ZB models.The analysis revealed that the relative errors associated with the three models were minimal.The time-domain approach necessitated the utilization of an extensive array of stress spectrum samples,whereas the frequency-domain technique offered a more computationally efficient alternative.The three models holds significant promise for widespread application in engineering practice.

关 键 词：起重机 疲劳寿命预测 有限元分析 应力在线监测 

分 类 号：TH114[机械工程—机械设计及理论] TH218