具初始裂纹的起重机焊接构件疲劳裂纹扩展实验和疲劳寿命估算  

作　　者：唐远辉 张克强[2] 汪可[2] 陈庆旭 施敏懿 

机构地区：[1]中国核动力研究设计院第一研究所,成都614100 [2]中国核动力研究设计院,成都614100

出　　处：《科技视界》2020年第11期152-155,共4页Science & Technology Vision

摘　　要：起重机构件因设计制造缺陷或在疲劳交变应力作用下易萌生裂纹,构件因存在初始裂纹大大降低其疲劳性能和使用寿命。文章以起重机典型结构形式箱型焊接构件为研究对象,搭建箱型(预制初始裂纹)试件疲劳裂纹扩展实验平台,开展Q 345钢材料焊缝处疲劳裂纹扩展特性研究,结合有限元分析软件Ansys计算裂纹应力强度因子,用实验测量计算Q 345钢焊材的两个重要裂纹扩展参数,在此基础上建立具初始裂纹起重机焊接构件疲劳剩余寿命数值估算方法。Initial crack widely exits in the welded crane members.These cracks are induced by defect of design and manufacturing and effect of alternate fatigue stress.The fatigue performance and remaining life of welded components which have initial crack is significantly reduced.In the paper the typical box-type welded components of crane are discussed.Based on fatigue propagation experiment of box-type specimen with initially prefabricated crack,the fatigue propagation feature of weld area of Q345 steel is studied.Meanwhile finite element software Ansys is used to calculate the stress intensity factor.Combining experimental data and calculated result of stress intensity factor,two important propagation parameters of Q345’s weld area are acquired.The experiment result can be applied to evaluate the remaining fatigue life of welded crane members with initial crack.

关 键 词：焊接构件 初始裂纹 疲劳扩展实验 应力强度因子 有限元 疲劳剩余寿命 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]