基于光纤光栅传感的管路损伤测量与定位

Research on damage measurement and orientation of pipeline based on fiber Bragg grating sensing

利用光纤光栅传感技术,以频率法进行损伤识别为基础,研究运用光纤光栅传感器测量管路损伤前后各阶频率变化率的比值进行损伤定位的方法.以不锈钢管为研究对象,通过伯努利-欧拉梁理论求得管路曲率模态振型,应用光纤光栅和加速度计分别测量管路损伤前后的固有频率,并求得各阶频率的变化率.结果表明:与加速度计的测量值比较,光纤光栅由于其质量更轻,对被测对象影响更小,测量值更为准确;另外,根据实测数据,使用频率变化率的比值可以很好地识别管路的损伤位置.

Based on fiber grating sensing technology and damage identification of frequency domain method,the method for damage orientation of pipeline was researched,which utilized fiber Bragg grating（FBG）sensor to measure the ratio of frequency change rate before and after damage of pipeline.A stainless steel tube was researched,and curvature mode shape of pipeline was calculated through the theory of Bernoulli-Euler beam.Frequency was measured utilizing FBG sensors and the accelerometer before and after damage of pipeline,and frequency change rate was calculated.The results show that compared to the accelerometer,the FBG measurement results are more accurate with a negligible mass,and according to measured data of FBG,the damage location of pipeline can be identified well utilizing the ratio of frequency change rate.