FBG应变传感器应力疲劳极限传感寿命评估方法  

Evaluation Method of Ultimate Sensing Life for Stress Fatigued FBG Strain Sensors

作　　者：舒岳阶[1,2] 吴俊[2] 周世良[2] 周远航[2] 

机构地区：[1]重庆交通大学内河航道整治技术交通行业重点实验室,重庆400074 [2]重庆交通大学西南水运工程科学研究所,重庆400016

出　　处：《光子学报》2018年第1期100-105,共6页Acta Photonica Sinica

基　　金：国家自然科学基金(No.51508059);内河航道整治技术交通行业重点实验室开放基金(No.NHHD-201502);宁波市交通运输科技项目(No.201704)资助~~

摘　　要：光纤光栅应变传感器在应力疲劳作用下不可避免地出现性能衰退,为了评估其极限传感寿命,从光纤光栅传感原理出发,理论推导了应力疲劳作用引起的满度相对误差表达式,以工业仪表精确度等级作为传感器的极限状态阈值,提出了基于等强度梁的极限传感寿命测试方法.利用该方法评估了高桩码头结构健康监测应用环境中光纤光栅应变传感器的极限传感寿命,以满度相对误差变化4%作为极限失效阈值,对4支传感器进行了1.32亿应力疲劳实验.当疲劳至1.32亿次时,2支传感器达到极限传感寿命,1支传感器接近极限传感寿命,即极限传感寿命约为1.32亿次.实验结果表明,提出的方法能有效地测试不同结构健康监测需求下,光纤光栅应变传感器的应力疲劳极限传感寿命.The performance degradation of fiber Bragg grating strain sensors is unavoidable under stress fatigue, in order to assess the ultimate sensing life of fiber Bragg grating sensors, the full scale relative error expression of stress fatigue effect is deduced from the principle of fiber Bragg grating, and the industrial instrument accuracy class is used as the limit state threshold of the sensor. And then a method based on the beam of constant strength is put forward to test the ultimate sensing life. The ultimate sensing life of fiber Bragg grating in high pile wharf structural health monitoring application is assessed by this method, the failure threshold of full scale relative error is set as 4%, 4 fiber Bragg grating sensors suffer from 132 million times alternate strain, when the fatigue number reach to 132 million times, 2 sensors reach the ultimate sensing life, 1 sensor proximity reach the limit. That is, the maximum sensing life is 132 million times. Experimental results show that the proposed method can effectively test the ultimate sensing life of stress fatigued fiber Bragg grating strain sensors in different structural health monitoring application.

关 键 词：光纤光学 极限传感寿命 应力疲劳 光纤光栅 满度相对误差 等强度梁 

分 类 号：TN253[电子电信—物理电子学]