400 km·h^(-1)高速道岔号码选型与结构优化

Number selection and structural optimization of 400 km·h^(-1)high-speed turnout

基于中国高速铁路进一步提升运营速度的需求,系统研究了400 km·h^(-1)高速道岔号码选型与结构优化方法;基于车辆-道岔耦合动力学仿真,分析了道岔号码与平顺性的关系,并给出了号码选型建议;研究了道岔线型对动力学性能的影响,并考虑既有岔枕通用原则,提出了线型优化方案;建立了客专线18号道岔尖轨转换原型试验平台,研究了尖轨不足位移的影响因素与影响机制,提出了尖轨不足位移的控制方法;基于有限元理论,建立了道岔区轨道刚度计算模型,结合岔区钢轨动位移现场实测数据,提出了岔区轨道刚度目标取值与均匀化方案。研究结果表明:在现有车站布置方案条件下,400 km·h^(-1)高速道岔仍建议选择18号道岔;将400 km·h^(-1)高速道岔相离值增大至28 mm,可显著提升耐磨性能与使用寿命,也可实现岔枕通用;综合考虑系统匹配设计、制造工艺、工电结合要求等多方面因素,建议将第三牵引点至固定端距离减小600 mm,可减小尖轨不足位移,同时最小轮缘槽和第三牵引点牵引力符合规范要求;建议改进高速道岔辙叉结构设计方法,根据实际受力确定心轨弹性变形状态,在此基础上进行连接件与心轨转换设计;建议岔区目标刚度由25±5 kN·mm^(-1)减小为23±3 kN·mm^(-1)。

According to the demand for further improving the operating speed of high-speed railways in China,the number selection and structural optimization methods of a 400 km·h^(-1)high-speed turnout were studied systematically.Based on the vehicle-turnout coupling dynamics simulation,the correlation between turnout number and ride comfort was analyzed,and the suggestions for number selection were given.The influence of turnout linetype on the dynamics performance was studied,the principle of utilizing existing turnout sleepers was considered,and a linetype optimization scheme was proposed.A prototype test platform for the switch rail conversion of the No.18 KEZHUANXIAN turnout was established.The influencing factors and mechanisms of insufficient switch rail displacement were studied,and a control method of the insufficient displacement was proposed.A calculation model of track stiffness in the turnout area was established based on the finite element theory.According to on-site measured data of rail dynamic displacement in the turnout area,a target value and a homogenization scheme for track stiffness were proposed.Research results indicate that under the condition of the existing station layout plan,it is recommended to choose the No.18 turnout as the 400 km·h^(-1)high-speed turnout.The mutual distance of the 400 km·h^(-1)high-speed turnout can be increased to 28 mm,which can significantly improve the wear resistance and service life of the switch rail and can utilize the existing turnout sleepers.By comprehensively considering the system matching design,manufacturing process,combination requirements of track maintenance and electrical divisions,and other factors,it is recommended to reduce the distance from the third traction point to the fixed end by 600 mm,which can reduce the insufficient switch rail displacement.At the same time,the minimum flangeway and the traction force of the third traction point meet the code requirements.In addition,the structural design method of high-speed turnout crossings should be improved,in which the elastic deformation state of the point rail should be determined according to the actual forces,and the connectors and point rail conversion should be designed on this basis.It is also recommended that the target stiffness of the turnout area should be reduced from 25±5 kN·mm^(-1)to 23±3 kN·mm^(-1).