缆索内置光纤光栅传感器胶接植入试验研究

Experimental Study on the Embedding Method of Built-in FBG Sensor in Bridge Cable by Structural Adhesive-Bonding for Monitoring Cable Force

为实现光纤光栅传感器胶接固定于桥梁缆索钢丝以监测缆索索力,利用胶接结构的剪切测试、钢丝疲劳测试和循环加卸载测试分别对光纤光栅传感器支座与钢丝间胶接结构的剪切性能、疲劳可靠性以及胶接光纤光栅传感器的测试性能进行评估。试验发现:光纤光栅传感器支座与桥梁缆索钢丝间的胶接结构具有较大的剪切载荷,且200万次疲劳载荷对其胶接结性能影响较小;胶接固定于钢丝上的光纤光栅传感器可测出钢丝加卸载的滞回效应,并每个循环加、卸载的波长和钢丝承载载荷关系呈线性且分别重合。结果表明:内置光纤光栅传感器的胶接固定结构具有良好的剪切力学性能和疲劳可靠性,可保证其光纤光栅传感器的测试具有良好的准确、稳定、可靠性。

To achieve the application of adhesive-bonding fibre Bragg grating sensors with steel wire of bridge cable for monitoring the cable force,the shear test was performed for the adhesive-bonded seat of FBGs with steel wire and the effect of fatigue load on the adhesive-bonded structure was investigated. Based on the mechanical properties of the adhesive-bonded seat of FBGs with steel wire,the measurability of FBGs in the adhesive-bonded structure was assessed by the loading-unloading cyclic test. The results showed that the adhesive-bonded FBG seats with steel wire had a great shear load,and 200 million fatigue cycle of steel wire had little influence on its residual shear load. The FBG sensor by adhesive-bonded with steel wire could detect the hysteretic effect of steel wire at the loading and unloading phases,and there was a good linear relationship between wavelength from the FBG sensor and load at steel wire. These results indicated that the adhesive-bonded FBG sensor with steel showed a good shear and fatigue properties,which could ensure that the adhesive-bonding FBG sensor had a good accuracy,stability and reliability.