基底刻槽封装式光纤光栅传感器应变传递影响因素分析

Strain Transfer Factor Analysis of Basal Grooving Encapsulating Fiber Bragg Grating Sensor

光纤光栅传感器大多经过封装后粘贴于被测结构表面使用,而封装基底和粘胶的存在,导致结构的真实应变与光纤光栅感测值之间出现偏差。建立了基底刻槽封装的光纤光栅传感器应变传递力学简化模型,推导出相应的平均应变传递率公式;分别分析了基底的长、宽、厚和基底材料弹性模量对光纤光栅传感器平均应变传递率的影响。结果表明,采用刻槽封装后的光纤光栅传感器平均应变传递率,在有效范围内随着基底长度的增加而增加,随着基底的宽、厚和材料弹性模量的增加而减小,为光纤光栅刻槽封装提供定量的指导。

Fiber Bragg grating（FBG） sensor was mostly pasted on the structure surface to measure the strain after encapsula- ting.However, as the existence of encapsulating basement and viscose, there were some deviations between real strain and FBG sensing value.The simplified strain transfer mechanics model of basal grooving encapsulating FBG sensor was established, and the corresponding average strain transfer ratio formula was deduced.The impact of length, width, thickness and elastic modulus of the base on the average strain transfer rate was analysed.The results show that within the effective range, the average strain transfer rate of basal grooving encapsulating FBG sensor increases with the rise of basement length, decreases with the growth of basement width, thickness and material elastic modulus, providing quantitative guidance for FBG grooving encapsulation.