智能光纤技术在简支转连续梁桥施工中的应用

Monitoring in the Construction of Continuous Beam Turned from Sample Beam on FBG

在研究光纤传感器原理的基础上 ,进行了室内标定和布设工艺的研究 ,并在简支转连续梁施工的黑大公路牛头山大桥上布设了光纤光栅应变传感器 ,监测了预应力箱形梁张拉过程的钢筋应变历程 ,以及单梁静载试验的钢筋和混凝土的应变。通过近 12个月的施工全过程观察 ,实践证明光纤传感器读数稳定 ,性能可靠 ,可以用于桥梁长期监测 ,作用明显优于传统的电阻应变片。

Indoors standardization and layout techniques were studied based on the analysis of the principle for fiber Bragg grating (FBG) sensors. The FBG sensors have been successfully installed in the prestressed box girder during the construction of continuous beam turned from sample beam in Niutoushan River Bridge of Heida road. Single beam dead load test was made for strain of steel and concrete. The fact that the FBG strain sensors have withstood the ordeal for more than one year proves that their durability and stability can satisfy the need of health monitoring for bridges, and that the performance of FBG strain sensor is superior to that of electric strain gauge.