基于分布式FBG的钢轨动静态载荷监测研究

针对铁道领域钢轨应变监测需求，提出一种基于光纤Bragg光栅（ FBG）传感器的钢轨应变监测系统。从静态载荷监测角度，研究了不同加载位置的FBG传感器中心波长随加载载荷大小变化的关系。从动态载荷监测角度，研究了循环加载状态下的各FBG传感器中心波长偏移量特性。研究表明：在静态载荷作用下，各FBG传感器中心波长偏移量均随加载载荷增大而呈现良好线性变化关系，且传感器对载荷加载距离和角度变化较为敏感。在动态循环载荷作用下，FBG传感器网络能够较好地实现对钢轨应变和温度参量的实时监测。这些研究为钢轨应变与损伤分布式在线监测技术提供了有益借鉴。

Study of monitoring on rail dynamic and static load based on distributed FBG

Aiming at needs of strain monitoring of rail in railway field,a kind of rail strain monitoring system is proposed,which is based on fiber Bragg grating( FBG)sensor. From the point of static load monitoring,relation between center wavelength of FBG sensor and change of loading size is studied,when loading is applied at different positions. From the point of monitoring dynamic load,features of center wavelength offset of every FBG sensor center under the cyclic loading is studied. The study shows that,under the static load,offsets of every FBG center wavelength increases along with the increase of load and shows a good linear relationship,and FBG sensor is sensitive to the distance and angle change of the load. Under the cyclic loading,FBG sensing network can realize the real-time monitoring of rail strain and temperature parameters very well. These studies can provide useful references for distributed online monitoring technology of rail strain and damage monitoring.