一种具有温度补偿的'王'字形FBG应变传感器研制

摘要

针对铁轨温度与外载应力实时监测,设计了一种"王"字形FBG应变传感器.该传感器借助一组平行布置但彼此相连的带狭长矩形窗口的基片,将2根FBG悬空粘牢,通过基片的固连和紧贴实现具备温度补偿的应变测量,同时防止啁啾.采用有限元仿真分析传感器的应变和温度特性,并进行基于强度梁的传感器标定;最后,在高速铁路60轨道上进行了实测.仿真与实验结果表明,该传感器既可进行结构温度测量,又能实现铁轨温度补偿后的外载应变测量.%A type of "王" shaped FBG strain sensors was designed for real-time monitoring of the temperature and external strain loadings for the steel rails simultaneously.Two FBG sensors were fixed along split parallel blind slots in a narrow aluminum substrate with rectangular hollow windows for dangling sensing parts. The substrate is contacted with the object. The temperature compensated strain measurement is realized by bonding and sticking of the substrate,and the chirp is prevented simultaneously. The strain and temperature characteristics of the sensor were simulated using ANSYS.And the sensors are calibrated based on the strength beam.Finally,the sensors are applied on the 60 track of high-speed railway.The simulation and experimental results show that the sensors can obtain the temperature independently,but also separate the external loading strains from the temperature.