The inclusion of sensors in railway track components will permit the automated and real-time monitoring of track behaviour and traffic conditions; necessary for adopting preventive maintenance strategies. In this sense, this paper assesses the applicability of three different sensor types, commonly used for engineering applications, to be included into rail pads to thus provide smart components with sensing properties to monitor railway tracks. Various types of accelerometer, piezoresistive and piezoelectric sensors were evaluated to determine their viability for smart rail pads. Results demonstrated that piezoelectric devices showed a linear correlation between signal output and stress levels on pads, in contrast to piezoresistive panels which presented a logarithmic response, and clearer signal pulses than the other sensors to detect changes in loading conditions or track response. Therefore, piezoelectrics presented the highest implementation potential for this application, considering its low cost and clearer ability to monitor variations in traffic and/or track state.

在铁路轨道组件中包含传感器将允许自动和实时监控轨道行为和交通状况；采取预防性维护策略所必需的。从这个意义上说，本文评估了通常用于工程应用的三种不同传感器类型的适用性，它们被包含在轨道垫中，从而提供具有传感特性的智能组件来监控铁路轨道。评估了各种类型的加速度计、压阻式和压电式传感器，以确定它们在智能轨道垫上的可行性。结果表明，压电设备显示出信号输出和垫上的应力水平之间的线性相关性，与呈现对数响应的压阻面板相反，和比其他传感器更清晰的信号脉冲，以检测负载条件或跟踪响应的变化。因此，考虑到压电材料的低成本和更清晰的监测交通和/或轨道状态变化的能力，压电技术在该应用中具有最高的实施潜力。