基于OFDR裸光纤表面粘贴式应变传递的分析及试验研究

Analysis of Surface-Bonded Strain Transfer Using Optical Frequency Domain Reflectometry Bare Fiber

分析了光纤传感器应变传递率的影响因素,进行了粘贴式光纤传感器等强度梁试验。光纤传感器监测结构材料中应变分布的能力取决于材料与光纤之间的键合特性。取粘贴长度和胶体剪切模量两个参数,研究了分布式光纤传感器应变传递的顶端效应。结果表明:延长粘贴的光纤长度或提高胶体的剪切模量,可以使高应变传递段加长。工程应用中应选用剪切模量高的胶黏剂,粘贴长度应在粘贴测量段两端多粘贴5 cm,以保证测量段可以得到相对精确的应变结果。

In this study,the influential factors that impact the strain transfer rate of the optical fiber sensor are analyzed.The fiber sensors’ability to monitor strain distribution in structural materials depends on the bonding characteristic between the material and fiber.The strain transfer tip effect of the distributed fiber sensor is studied;the two parameters,paste length and colloidal shear modulus,are examined to assess the impact on the strain transfer rate.The results show that the strain transfer length can be increased by prolonging the length of the pasted fiber or increasing the shear modulus of the colloid.Adhesive with high shear modulus should be selected in the engineering application,and the paste length(greater than 5 cm)should be pasted at both ends of the paste measuring section to ensure that the strain results are accurate in the measuring section.