边界载荷反求法分析推耙机的焊接结构疲劳

发布时间：2018-09-09 10:27

【摘要】：针对工程装备焊接结构模型复杂、计算数据庞大导致的疲劳寿命难以预测问题,该文将带有缺陷的局部结构体分离出来单独进行分析,采用有限元和应力解析计算方程获得测试应力(应变)和结构体边界载荷之间的关系,以便反求得到局部结构体的外载荷,进而应用降维多轴疲劳损伤模型开展局部结构体裂纹扩展寿命的研究。以存在多条焊缝的推耙机H形架横梁为对象设置初始裂纹来模拟焊接缺陷,基于测试数据确定横梁的等效边界载荷并进行疲劳寿命计算,预测得到的H形架横梁使用寿命与工程实际寿命误差在5%以内,说明该方法是切实可行的。该研究可为工程结构设计及制造精度控制提供参考。
[Abstract]:As the welding structure model of engineering equipment is complex and the fatigue life is difficult to predict due to the huge calculation data, the local structure with defects is separated out and analyzed separately in this paper. The relationship between the measured stress (strain) and the boundary load of the structural body is obtained by using the finite element method and the stress analytic equation, so that the external load of the local structural body can be obtained. Then the crack propagation life of local structures is studied by using the reduced dimension multiaxial fatigue damage model. In order to simulate the welding defects, the initial cracks were set up in the H-shaped frame crossbeam of a rake machine with multiple welds. The equivalent boundary load of the beam was determined based on the test data and the fatigue life was calculated. The predicted error between the service life of the H-shaped beam and the actual life of the project is less than 5%, which shows that the method is feasible. The research can provide reference for engineering structure design and manufacturing precision control.
【作者单位】：浙江大学机械工程学院;山推工程机械股份有限公司;中国北方车辆研究所;
【基金】：国家自然科学基金(51175457,51475416) 中央高校基本科研业务费专项资金(2014QNA4003)
【分类号】：TG405

【二级参考文献】