市域铁路车场线50 kg/m钢轨9号有砟道岔优化设计研究

Research on the Optimized Design of 50 kg/m Rail No.9 Ballasted Turnout for Urban Railway Depot Lines

针对既有50 kg/m钢轨9号有砟道岔常见问题,将高速和重载铁路道岔设计创新成果应用于市域铁路车场线50 kg/m钢轨9号有砟道岔研发中,采取系列优化措施提升道岔性能,建立道岔辙叉和尖轨薄弱环节的有限元分析模型,开展受力性能强度检算。结果表明:新型50 kg/m钢轨9号有砟道岔采用相离25 mm、R200 m的相离半切线型单圆曲线平面线型,道岔全长28.848 m,前长13.118 m,后长15.730 m,冲击角为0°49′9″;新型道岔基于CZ2209型道岔,在平面线形、转辙器、辙叉、护轨、岔区扣件系统等方面进行了系列改进优化,提高了道岔性能,减少了后期养护维修工作量;辙叉在薄弱位置的竖向位移在2 mm以内,横向位移在1 mm以内,应力峰值为326.338 MPa,辙叉强度能满足使用要求,且具有一定强度储备;在准静态荷载、疲劳荷载作用下,尖轨顶宽5~50 mm各断面处的应力均在容许限值范围内,强度满足要求,且具备较大安全余量。

In response to common problems with the existing 50 kg/m rail No.9 ballasted turnout,innovative design achievements for high-speed and heavy-duty railway turnouts are applied to the research and development of the 50 kg/m rail No.9 ballasted turnout for urban railway yard lines.A series of optimization measures are taken to improve the performance of the turnout,and a finite element analysis model is established for the weak links of the turnout frog and switch rail,and the strength calculation of the stress performance is carried out.The results show that the new 50 kg/m rail No.9 ballasted turnout adopts a phase separated semi tangent single circular curve plane shape with a phase separation of 25 mm and R200 m.The total length of the turnout is 28.848 m,with a front length of 13.118 m and a rear length of 15.730 m,and an impact angle of 0°49′9″.The new turnout is based on the CZ2209 turnout and has undergone a series of improvements and optimizations in the plane shape,switch,frog,guard rail,and switch area fastening system,which improves the performance of the turnout and reduces the workload of later maintenance and repair.The vertical displacement of the frog at weak positions is within 2 mm,the lateral displacement is within 1 mm,and the stress peak is 326.338 MPa.The strength of the frog can meet the requirements for use and has a certain strength reserve.Under quasi-static and fatigue loads,the stress at each section of the pointed rail top width of 5~50 mm is within the allowable limit,and the strength meets the requirements with a large safety margin.