客货混运铁路行车诱发场地与建筑振动实测研究

Field Study on Vibration Impact of Mixed Passenger-Freight Railway Operations on Surrounding Site and Building Structures

摘要: 普速客货混运铁路列车低速进出站时，货运列车产生的低频振动对沿线高层建筑的干扰明显大于纯客运线路。现有轨道交通振动实测研究以地铁和高铁为主，针对普速客货混运场景的分析相对不足。本文以京承铁路北京–怀柔段为对象，2024年3~5月间在昼间开展了28次现场振动测试。沿垂直于线路方向布设了场地监测断面，同时在距线路75 m和270 m的两栋高层建筑内布置楼层测点，记录列车以25~50 km/h进出站时的竖向振动响应。实测发现：货车的优势频段为2~8 Hz，客车则集中在10~30 Hz；低频振动在90~180 m测试范围内衰减速率低于中高频。75 m处建筑出现楼层振动放大，其竖向基频与货运低频激励接近，形成共振，室内Z振级超过居住建筑舒适限值。基于实测结果，建议铁路沿线新建住宅与线路的距离宜大于200 m；受用地条件限制时，需针对性设计低频隔振系统。

Abstract: Field measurements were conducted on the Beijing-Huairou section of Jingcheng Railway to investigate ground and building vibrations induced by mixed passenger-freight trains during low-speed arrival and departure. A total of 28 valid test groups were completed between March and May 2024. Three ground monitoring points were arranged at 90 m, 125 m and 180 m from the track centerline, and floor measuring points were installed in two high-rise buildings located 75 m and 270 m away, respectively. Test results show that freight trains generate dominant vibration in the 2~8 Hz range, whereas passenger trains dominate at 10~30 Hz. Within the 90~180 m range, low-frequency vibration decayed more slowly than mid-to-high-frequency components. Building A at 75 m exhibited significant floor amplification: the 25th-floor Z-vibration level reached 72 dB under freight train excitation, 5 dB above the ground level and exceeding the 65 dB sleep comfort limit specified in JGJ/T 170-2009. The vertical transfer function revealed a structural resonance peak at 6.73 Hz, which falls within the freight train’s dominant frequency band, yielding a 25th-floor transfer rate of 3.58-approximately 6.4 times that under passenger train excitation. At 270 m, Building B met all vibration comfort criteria. Conventional mitigation measures, including structural stiffness adjustment, isolation trenches, polyurethane pads and steel spring-damper bearings, face frequency or scale mismatch issues in the 2~10 Hz range and are unlikely to achieve effective low-frequency isolation. A minimum setback distance of 200 m is recommended for new residential buildings along such railway lines; where land availability is constrained, dedicated low-frequency isolation systems should be developed.