Vibration serviceability of a GFRP railway crossing due to pedestrians and train excitation
Vibration serviceability of a GFRP railway crossing due to pedestrians and train excitation
复制标题
DOI：
10.1016/j.engstruct.2020.110756
复制
发表时间：
2020-09
影响因子：
5.5
通讯作者：
J. Russell;Xiaojun Wei;S. Z̆ivanović;C. Kruger
中科院分区：
文献类型：
--
作者：
J. Russell;Xiaojun Wei;S. Z̆ivanović;C. Kruger
玻璃纤维增强聚合物（gfrp）是铁路线上人行天桥的热门选择，因为它们对安装或维护造成的干扰很小。然而，由于它们通常比传统材料更轻，硬度更低，因此人们担心它们由于人为行为和列车抖振而产生的动态响应。由于缺乏实验信息，如果在未来的线路上使用这种桥梁，特别是在更高的速度限制下，还需要进一步的数据。本文对一座14.5 m玻璃钢桁架桥在行人荷载和列车振动作用下的响应进行了试验研究。通过冲击锤试验确定了感兴趣的振动模式。测量了一系列人类负载场景以及多个列车通道的振动响应。在所有条件下，振动水平都保持在较低水平，这表明这种特殊类型的玻璃钢桥梁适用于铁路道口，设计师可以在满足振动使用限制的情况下进行进一步优化。然而，考虑到载荷，GFRP桥梁可能比传统结构更容易受到更高行人谐波的影响，并且火车抖振可能是未来高速线路桥梁的设计考虑因素。
Glass Fibre-Reinforced Polymers (GFRPs) are a popular option for pedestrian bridges over railway lines as they cause little disruption for installation or maintenance. However, as they are typically lighter and less stiff than traditional materials there is concern about their dynamic response due to human induced actions and train buffeting. Due to a lack of experimental information, further data is needed if such bridges are to be used on future lines, especially with higher speed limits. This paper presents an experimental investigation of the response of a 14.5 m GFRP truss bridge due to pedestrian loading and train induced vibrations. Vibration modes of interest were identified from impact hammer tests. The vibration responses to a range of human loading scenarios, as well as multiple train passes, were measured. The vibration levels remained low under all conditions, demonstrating that this particular type of GFRP bridge is suitable for railway crossings and that further optimisations may be available to designers while meeting vibration serviceability limits. However, consideration of the loadings suggests GFRP bridges may be more susceptible to higher pedestrian harmonics than traditional structures, and that vibrations from train buffeting are likely to be a design consideration for future bridges over high speed lines.