基于分布式光纤传感的隧道模型应变沉降研究

Research on Strain Settlement of Tunnel Model Based on Distributed Optical Fiber Sensing

以有机玻璃为模型材料,设计和制作了隧道模型结构,使用电阻应变片和分布式传感光纤作为监测手段,对该隧道模型进行荷载对比试验,结果表明分布式光纤不仅实现隧道模型结构上连续的分布式应变测量,而且测量结果与应变片相一致。同时采用二次积分法,将分布式传感光纤得到的应变量换算成沉降值,与百分表测值进行比对,得到的沉降量与实测结果存在较小的误差,说明分布式光纤传感技术在隧道应变、沉降监测中的可行性。

The tunnel model structure is designed and fabricated by using plexiglass as the model material. The load strain test is carried out by using the strain gauge and the distributed sensing fiber as the monitoring means. The results show that the distributed fiber not only realizes the continuity of the tunnel model structure. Distributed strain measurement, and the measurement results are consistent with the strain gauge. At the same time, the secondary integral method is used to convert the strain amount obtained by the distributed sensing fiber into the settlement value, and compare it with the measured value of the dial gauge. The obtained settlement amount has small errors with the measured result, indicating. The feasibility of distributed optical sensing technology in tunnel strain and settlement monitoring is illustrated.