基于分布式光纤感测技术的路基边坡失稳过程试验研究

Experimental Study on Failure Process of Subgrade Slope Based on Distributed Optical Fiber Sensing Detection Technology

为了探究路基边坡在附加荷载作用下的变形失稳模式,开发了一套边坡模型试验装置和包含分布式光纤传感技术的测试系统。在边坡内部不同高度植入了应变感测光纤、FBG应变和温度传感器以实时获取边坡模型内部应变分布和发展信息。试验结果表明:基于FBG应变传感器和OBR技术的应变监测数据反映了边坡失稳的过程,与边坡表面位移的观测结果十分一致,根据应变发展信息将路基边坡失稳破坏的过程划分为三个阶段。此外,根据每条监测线路的最大应变位置,定出边坡潜在滑动面的准确位置。

In order to explore the deformation failure mode of subgrade slope under the action of additional load,a test unit for slope model and a testing system including distributed optical fiber sensing technology were developed.Strain sensing fibers and FBG strain and temperature sensors were embedded into slope at different heights to obtain the real-time data of strain distribution and development inside the slope model.The test result shows that the strain monitoring data based on FBG strain sensors and OBR technology reflects the slope failure process,and is consistent with the observation of slope surface displacement;according to the strain development data,the failure process of subgrade slope is divided into three stages.In addition,according to the location of maximum displacement on each monitoring line,the potential sliding plane is positioned accurately.