Over the past 20 years, there have been at least 10 derailments due to spike fastener fatigue failures in North America. These fatigue failures have been considered a moderate to severe challenge that require manual walking inspections that are both time and labor intensive. These fatigue failures have been found to result from spike overloading due to lateral and longitudinal loads. To date, there has been limited quantification of the vertical, lateral, and longitudinal fastener forces in track. This paper quantifies the effect of fastener type on fastener load to account for various track types and locations. Laboratory experimentation was performed to quantify the stiffness of multiple fastening systems and this data was input into a previously validated analytical model to quantify the effect of stiffness on fastener loading. Additional laboratory experimentation was performed to quantify the relationships between both fastening system type and vertical loading and spike strain. While the laboratory data indicate a significant variance in stiffness between fastening systems, the model results indicate that the load transferred to the fastening system is less sensitive. However, spike strain data indicate the load path was affected by fastener type and vertical load. The characterization of longitudinal stiffness of multiple fastening systems and the relationship to spike load as presented can be used to advance track mechanistic-empirical design and improve rail neutral temperature prediction and track buckling models.

在过去的 20 年中，北美至少有 10 起因道钉紧固件疲劳失效而脱轨的事件。这些疲劳故障被认为是中度到严重的挑战，需要人工步行检查，既费时又费力。已发现这些疲劳失效是由横向和纵向载荷引起的尖峰过载造成的。迄今为止，对轨道中垂直、横向和纵向紧固件力的量化有限。本文量化了紧固件类型对紧固件负载的影响，以考虑各种轨道类型和位置。进行了实验室实验以量化多个紧固系统的刚度，并将该数据输入到先前验证的分析模型中，以量化刚度对紧固件负载的影响。进行了额外的实验室实验以量化紧固系统类型与垂直载荷和尖峰应变之间的关系。虽然实验室数据表明紧固系统之间的刚度存在显着差异，但模型结果表明传递到紧固系统的载荷不太敏感。然而，尖峰应变数据表明载荷路径受紧固件类型和垂直载荷的影响。多个扣件系统的纵向刚度特征以及与所呈现的尖峰载荷的关系可用于推进轨道机械经验设计并改进轨道中性温度预测和轨道屈曲模型。虽然实验室数据表明紧固系统之间的刚度存在显着差异，但模型结果表明传递到紧固系统的载荷不太敏感。然而，尖峰应变数据表明载荷路径受紧固件类型和垂直载荷的影响。多个扣件系统的纵向刚度特征以及与所呈现的尖峰载荷的关系可用于推进轨道机械经验设计并改进轨道中性温度预测和轨道屈曲模型。虽然实验室数据表明紧固系统之间的刚度存在显着差异，但模型结果表明传递到紧固系统的载荷不太敏感。然而，尖峰应变数据表明载荷路径受紧固件类型和垂直载荷的影响。多个扣件系统的纵向刚度特性以及与所呈现的尖峰载荷的关系可用于推进轨道机械经验设计并改进轨道中性温度预测和轨道屈曲模型。