摘要
采用大型有限元软件分析WJ-7型扣件弹条在列车运行下所引起的铁轨对弹条的冲击,建立详细的扣件系统有限元模型,基于车辆轨道耦合动力学理论下分析WJ-7型扣件弹条在安装过程中的受力,以及列车冲击荷载作用下的受力特性。分析静力与冲击力下的应力大小与位置,在不同冲击力作用下发现弹条的最大应力发生在与铁垫板接触的部位,最大应力为1 853 MPa。10kN的扣压力下的静力分析,弹条的最大应力同样发生在与铁垫板接触的部位,最大应力为1 765MPa。弹条与绝缘块接触部位为了实现固定钢轨的作用受到的冲击随着冲击力的增大位移也不断增加,同时两臂向上翘起且变形越来越明显,弹条的弹程随扣压力的增大呈线性增加趋势。随着列车的反复通过,弹条容易在这区域萌生裂纹最终裂纹扩展导致弹条发生疲劳断裂。数值分析结果与现场多处弹条断裂破坏位置吻合,分析结果可为以后弹条的设计、优化、安全提供参考依据。
In order to analyze the impact of the railway track of the WJ-7rail fastening clip by the high speed running,using the FEA Midas finite element software to establish the finite element model of the fastener system.Based on the theory of vehicle track coupling dynamics,analysising of the stress characteristics of WJ-7type fastener bullet strip during installation and under the influence of train impact load.Comparing to the stress position and size under static and impact stress or different impact force.Elastic bar in impact force of 1kn,2Kn and 3kn,which is found maximum stress occurs at the contact site of elastic bar and iron backing plate.The maximum stress is 1 853 MPa.In the 10 kN buckle pressure of the static analysis,elastic strip maximum stress also occurred at the contact with the iron plate part,the maximum stress for 1765 MPa.With the passage of the train,the elastic strip is easy to crack propagation in this region and the final crack propagation leads to fatigue fracture.The numerical analysis results are consistent with the location of multiple elastic strip breakage and the results can provide reference for the design,optimization and safety of the elastic strip in the future.
引文
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