桥梁施工过程的布拉格光纤光栅安全监测技术

为了安全可靠地建好每座大跨桥梁,就要对每座桥的施工过程进行安全监测,传统的安全监测方法是采用电测技术,由于抗电磁干扰性差等原因,测试的数据真实性差。笔者在布拉格光纤光栅的传感原理、室内悬臂梁试验和埋设工艺的研究基础上,成功地在黑大公路牛头山大桥上布设了布拉格光纤光栅应变传感器,为对比布拉格光纤光栅的监测结果,埋设了应变砖测试混凝土的应变,监测了该桥预应力混凝土连续梁先简支后连续施工的全过程,施工监测结果表明:布拉格光纤光栅监测大桥施工结果准确、稳定和可靠,同时证明该光纤光栅测试技术可以用于桥梁施工过程的安全监测且结果明显好于传统的电测技术。

Fiber Bragg Grating Monitoring Technology in Process of Bridge Construction

In order to make every long span bridge being constructed safely and reliably,the construction process of the bridge should be monitored for its safety.Traditional safety monitoring technology adopted the electrical strain gages,however, the electromagnetic anti-interference performance was poor and the authenticity of the test data obtained was rather poor.Based on the principle of Fiber Bragg Grating(FBG) sensing,through the study of indoor calibration and embedding process,FBG sensors were successfully embedded in Niutoushan Bridge of Heida Highway.In order to check the results tested by FBG concrete sensor,strain brick sensors were embedded in the concrete.The whole construction of continuous beam turned from simple beam was monitored.The result indicates that FBG sensor is stable and reliable in monitoring the construction of the bridge.At the same time,the FBG sensor could be used in monitoring the bridge construction and its performance is proved to be apparently better than that by the electrical strain gages.