【作者】 李健；

【导师】 孙传喜； 谭竑；

【作者基本信息】 大连交通大学 ， 车辆工程（专业学位）， 2021， 硕士

【摘要】 钢轨联接件鱼尾板又叫铁道接头夹板,它是两根钢轨进行对接的一个重要零件,它的作用是连接两根钢轨并使其平稳过渡。鱼尾板的材料力学性能会影响列车运行的平稳性、安全性。鱼尾板的失效或者断裂会加剧轨道的磨损,破坏轨道接头联结系统的正常工作状态,也会导致车辆结构其它零部件的破坏,严重危及列车的行车安全。因此,鱼尾板的力学性能是影响车辆安全运行的一个重要因素,对鱼尾板的力学研究是铁路发展过程中不可或缺的一部分。本文基于有限元理论,对60kg/m钢轨所配套的鱼尾板进行了接触力学分析,根据力学分析的结果,对60kg/m钢轨鱼尾板进行优化设计。依据模型的非线性接触理论,对鱼尾板进行有限分析模型的建立。对鱼尾板有限元模型进行接触性能分析,分析得出鱼尾板的内部应力大小、表面接触等效应力的分布情况和鱼尾板形变量位移情况。计算结果表明:在钢轨直线段中,钢轨会受到垂向载荷以及很小的横向载荷作用,鱼尾板的接触应力和位移量随着速度的增加而缓慢增长;在钢轨曲线区段上,钢轨同时受到横向载荷和垂向载荷的综合作用,鱼尾板的接触应力和位移量也随速度增大而缓慢增长。应力集中分布在钢轨和鱼尾板的接触区以及鱼尾板螺栓孔周围区域。本文考虑了轨缝大小的变化对鱼尾板应力分布的影响。由于外界环境温度发生变化,轨道会发生热胀冷缩现象,本文就我国东北地区冬夏两季温度变化为例,在冬季,钢轨发生收缩,轨缝值变大;在夏季,钢轨发生膨胀,轨缝值会减小。根据轨缝计算公式,分析不同轨缝值:8mm、12mm、16mm和20mm工况下鱼尾板的应力分布情况。根据计算结果显示:鱼尾板的最大等效应力值随着轨缝的变大而显著增长。本文针对鱼尾板的结构进行优化,选择对鱼尾板的螺栓孔形状进行改变,研究分析了螺栓孔处的应力变化,以防止该区域裂纹的产生与延展。通过计算结果表明:在螺栓孔形状改变后,鱼尾板整体的最大应力值下降并不十分明显,只下降了大约2.4%,但螺栓孔处最大应力值下降却尤为明显,大约下降了30.4%,达到了很好的优化效果。优化后的鱼尾板相比较优化前更加不容易萌生裂纹,延长其使用寿命,达到优化目的。更多还原

【Abstract】 Fishtail plate,also known as rail joint splint,is an important part for two rails to butt joint.Its function is to connect two rails and make them transition smoothly.The mechanical properties of fishplate material will affect the stability and safety of train operation.The failure or fracture of fishplate will aggravate the wear and tear of track,destroy the normal working state of track joint connection system,and also lead to the damage of other parts of vehicle structure,seriously endangering the safety of train operation.Therefore,the mechanical properties of fishplate is an important factor affecting the safe operation of vehicles,and the mechanical research of fishplate is an indispensable part in the process of railway development.In this paper,based on the finite element theory,the contact mechanics analysis of fishplate of 60kg/m rail is carried out.According to the results of the mechanical analysis,the fishplate of 60kg/m rail is optimized.According to the nonlinear contact theory of the model,the finite analysis model of fishplate is established.The contact performance of the finite element model of fishplate is analyzed,and the internal stress,surface contact equivalent stress distribution and deformation displacement of fishplate are obtained.The results show that: in the straight section of rail,the rail will be subjected to vertical load and small transverse load,and the contact stress and displacement of fishplate increase slowly with the increase of speed;In the rail curve section,the rail is subjected to both lateral and vertical loads,and the contact stress and displacement of fishplate increase slowly with the increase of speed.The stress concentration is distributed in the contact area between rail and fishplate and around the bolt hole of fishplate.In this paper,the effect of rail gap size on stress distribution of fishplate is considered.Due to the change of the external environment temperature,the track will expand and contract.This paper takes the temperature change in winter and summer in Northeast China as an example.In winter,the rail shrinks and the rail gap becomes larger;In summer,the rail expands and the rail gap decreases.According to the calculation formula of rail gap,the stress distribution of fishplate under different rail gap values: 8mm,12 mm,16mm and20 mm is analyzed.The results show that the maximum equivalent stress of fishplate increases significantly with the increase of rail gap.In this paper,the structure of fishplate is optimized,and the shape of bolt hole of fishplate is changed.The stress change of bolt hole is studied and analyzed,so as to prevent the generation and extension of cracks in this area.The calculation results show that: after the change of bolt hole shape,the maximum stress value of fishplate decreases not very obviously,only by about 2.4%,but the maximum stress value of bolt hole decreases significantly,about 30.4%,which achieves a good optimization effect.Compared with before optimization,the fishplate after optimization is more difficult to crack,which can prolong its service life and achieve the purpose of optimization.更多还原