沪宁城际WJ-7B型扣件螺栓轴力衰减规律与复紧周期探讨

高速铁路扣件系统是轨道弹性、轨距、水平调整能力的主要提供者,扣件的可靠性关系到列车运行的安全性和旅客乘车的舒适度等,对于WJ-7B型弹性分开式扣件,其功能的正常发挥很大程度上取决于锚固螺栓的预紧力是否足够。以沪宁城际WJ-7B型扣件系统为例,推导扣件系统螺栓轴力计算方法;结合现场转角测试结果计算锚固螺栓轴力的衰减规律。研究结论为:螺栓轴力稳定在40~60 kN,满足横向力校核结果,在此基础上确定了复紧周期为3~4年。

Approach to Bolt Axial Force Attenuation Law and Re-tight Period of WJ-7B Fastener of Shanghai-Nanjing Intercity Railway

High-speed railway fastening system is the main provider for track elasticity,gauge sustaining and level adjustment. Reliability of fasteners contributes to the safety of trains and passenger comfort.The normal function of WJ-7B indirect holding elastic fastener depends largely on the sufficient preload provided by the anchor bolt. This paper,taking the Shanghai-Nanjing Intercity Railway WJ-7B fastening system as an example,puts forward the method of calculating bolt axial force of the fastening system,draws up the attenuation law of the anchor bolt axial force in accordance with site corner test results. The study concludes that the axial bolt force maintained at 40 kN to 60 kN meets check requirements for lateral force and,therefore,the re-tight period is determined to be 3 to 4 years.