满载运煤敞车超常低周疲劳刚柔耦合评估新方法  

Novel method for assessing extraordinary low-cycle fatigue of laden coal gondola cars using the rigid-flex coupling simulation technique

作　　者：靳世英 朴思扬 聂春戈[2] 张俊林 李向伟 朴明伟[1] JIN Shiying;PIAO Siyang;NIE Chunge;ZHANG Junlin;LI Xiangwei;PIAO Mingwei(School of Mechanical Engineering,Dalian Jiaotong University,Dalian 116028,China;Zhan Tianyou College(CRRC College),Dalian Jiaotong University,Dalian 116028,China;Dalian R&D Center,CRRC Qiqihar Rolling Stock Co.,Ltd.,Dalian 116045,China)

机构地区：[1]大连交通大学机械工程学院,辽宁大连116028 [2]大连交通大学詹天佑学院(中车学院),辽宁大连116028 [3]中车齐齐哈尔车辆有限公司大连研发中心,辽宁大连116045

出　　处：《振动与冲击》2024年第22期70-80,共11页Journal of Vibration and Shock

基　　金：国家重点研发计划(2020YFB1200200ZL-02)。

摘　　要：备用传力路径变化不确定性使准静态应变能成为决定平面心盘旁承接口耦合程度的最重要影响因素之一,既有方法丧失了小位移线弹假设的应用前提。根据这一相关性发现,提出了刚柔耦合疲劳损伤评估新方法。为了攻克散料运输铁路货车刚柔耦合仿真难题,采用了实体单元及边界共节点处理技术。在正常AAR5级谱和局部扭曲叠加谱激励输入下满载运煤敞车刚柔耦合仿真分析表明:上旁承运行荷载增大迫使车体结构扭曲产生不高于2 Hz的低频敏感响应。钩缓冲击座附近焊缝疲劳损伤评估结果与现场塑性破坏完全吻合。由于局部刚度不足,短竖梁补强设计也很难奏效。借鉴通用敞车耳板铆接的设计经验,合理制定了具有针对性的结构补强方案,使满载运煤敞车不会再发生上述塑性破坏。The uncertainty of alternative load path variation makes the quasi-static strain energy become one of the most important factors determining the coupling extent on the interface of flat center plate and side-bearings.The application premise of existing methods is thereby no longer applicable because of the small displacement and linear elasticity assumption.In view of this consideration,a novel method for assessing fatigue damage was proposed using the rigid-flex coupling simulation technique.In order to overcome the difficulty in rigid-flex coupling simulations of rail freight cars for bulk material transportation,the solid elements were adopted and co-node treatment was introduced at the boundary.Under the excitation of both normal AAR5 spectrum and local twist superimposed spectrum,the results of rigid-flex coupling simulations and analyses for laden coal gondola cars indicate that an increase in the operating loads of upper side-bearings makes the distortion of carbody structure produce a low-frequency sensitive response of not higher than 2 Hz.The fatigue damage assessment results of the welds around the impact seat of hook and buffer are well consistent with the on-site inspected plastic failure phenomenon.Due to the insufficient local stiffness,the reinforced design of short vertical struts is also difficult to prove effective.Drawing on the experience of riveting design for ear plates in general gondola cars,a targeted structural reinforced design was reasonably formulated to prevent the laden coal gondola cars from the once more occurring of foregoing plastic damage.

关 键 词：满载运煤敞车 刚柔耦合仿真技术 模态结构应力恢复 焊缝疲劳损伤评估 超常低周疲劳 

分 类 号：U272.2[机械工程—车辆工程]