基于光纤传感技术的大型船闸人字门形变监测方法研究

Study on application of new optical fiber sensing technology in structural health monitoring of large ship lock

摘要:

为解决船闸人字门长期满负荷工作可能带来的结构安全问题，提出了一种基于新型光纤光栅(FBG)传感技术的人字门结构在线监测方法。采用304不锈钢和激光焊接工艺对传感器进行封装，解决了传感器在50m水深环境下的防水、耐压和成活率问题；通过对人字门结构进行建模与仿真，弄清门体受力分布及应力集中区，为传感器的敷设提供理论支撑；通过对闸门运行时的应力应变、塌拱度、裂纹等信息进行监测与分析，可为人字门结构安全评估提供数据支撑。实验结果表明，光纤光栅防水传感器在水下成活率高，具有良好的稳定性和重复性，其动态数据能够准确反映闸门开关过程、不同季节水位带来的应力变化。

Abstract:

In order to solve the structural safety problem of miter gates, a new on-line monitoring method based on fiber Bragg grating (FBG) sensing technology is proposed. The sensor is packaged by 304 stainless steel and laser welding technology, which solves the problems of water-proof, pressure-proof and survival rate of the sensor in 50m water depth. By modeling and simulating the structure of the miter gate, the stress distribution and stress concentration area of the gate body can be accurately understood, which provides theoretical support for the laying of sensors. The monitoring and analysis of the stress-strain, arch collapse, cracks and other information during the operation of the gate can provide data support for the safety assessment of the gate structure. The experimental results show that the fiber Bragg grating waterproofing sensor has high survival rate under water and good stability and repeatability, its dynamic data can accurately reflect the gate switching process, the stress changes caused by different seasonal water levels.