拱桥吊杆的光纤光栅监测与健康诊断

对拱桥吊杆内力监测光纤光栅(FBG)传感器的波长与应变和温度的关系进行了理论分析,通过标定试验,得到了FBG应变与温度灵敏系数.在四川峨边大渡河拱桥关键性吊杆中成功布设了FBG应变和温度传感器,提出并实施了现役拱桥吊杆FBG传感器的布设工艺以及布设后吊杆的修复方法.利用布设好的FBG传感器成功监测了车辆荷载下吊杆应变历程和温度变化过程、同一车辆荷载对不同长度吊杆的影响.监测结果表明:FBG传感器能够准确地监测车辆荷载大小和温度变化以其可能存在的损伤.

Fiber Bragg Grating Sensor Monitoring Techniques and Health Diagnosis of Arch Bridge Suspenders

The relationship between the wavelength of the arch bridge suspender tension monitoring FBG sensors and the strain and temperature has been studied theoretically, and the sensitivity coefficient is gotten through calibrating experiment. The FBG strain and temperature sensors have been successfully installed in some key suspenders of Sichuan Ebian Dadu river arch bridge. The installation of FBG sensors and suspender repair have been exp-lored in-service arch bridge. The change of suspender strain and temperature,and the effect of the same loading traffic on different length suspender have been monitored under traffic loading with the FBG sensors. The monitoring results show that the FBG sensors can monitor correctly the change of traffic loading and temperature, possible fatigue damages, and FBG sensors are more adaptive to long-term structural health monitoring than the electric strain gauges.