基于准分布式FBG阵列的大型机械结构应变监测研究

Research on Strain Monitoring Technique of Large-scale Mechanical Structure Based on Quasi-distributed FBG Array

针对机械加工制造中大型机械结构部位、尤其是壁板类零件在工况中受强过载容易造成结构强度失效等问题,采用准分布式光纤布拉格光栅(FBG)阵列对常见板状结构局部应变进行准分布式监测研究。在对应变传感器理论分析的基础上,结合波分复用技术,在一根光纤上接入9支FBG构成传感阵列,使其分布在板状结构表面。通过有限元理论分析与局部加载试验验证,证明了准分布式FBG传感阵列对大型机械结构进行应变监测的可行性。研究结果为结构健康监测提供了一种可靠的应变监测方法,为进一步研究准分布式FBG阵列的位置布局提供了有利的试验依据。

For large mechamcal structure parts m mechamcal manulacturing,especlally the panel parts which are easy to cause major problems such as structural strength failure under strong in overload conditious, this paper presents a method to monitor the local strain of common plate structure with the quasi-distributed fiber Bragg grating （FBG） array. Based on fiber Bragg grating （FBG） strain sensor theoretical analysis,the quasi-distributed sensing array with 9 FBGs is used to mo- nitor the local strain of plate-like structure by wavelength division multiplexing technology. It is proved that strain of large- scale mechanical structure monitored by the quasi-distributed FBG sensing array is feasible through finite element analysis and local loading experiments. The study result provides a reliable strain monitoring method in structural health monitoring and a favorable experimental basis for the position layout of quasi-distributed FBG array.