Fiber Bragg grating-based performance monitoring of a slope model subjected to seepage
In the past few years, fiber optic sensing technologies have played an increasingly important role in the health monitoring of civil infrastructures.These innovative sensing technologies have recently been successfully applied to the performance monitoring of a series of geotechnical structures.Fiber optic sensors have shown many unique advantages in comparison with conventional sensors, including immunity to electrical noise, higher precision and improved durability and embedding capabilities; fiber optic sensors are also smaller in size and lighter in weight.In order to explore the mechanism of seepage-induced slope instability, a small-scale 1 g model test of the soil slope has been performed in the laboratory.During the models construction, specially fabricated sensing fibers containing nine fiber Bragg grating (FBG) strain sensors connected in a series were horizontally and vertically embedded into the soil mass.The surcharge load was applied on the slope crest, and the groundwater level inside of the slope was subsequently varied using two water chambers installed besides the slope model.The fiber optic sensing data of the vertical and horizontal strains within the slope model were automatically recorded by an FBG interrogator and a computer during the test.The test results are presented and interpreted in detail.It is found that the gradually accumulated deformation of the slope model subjected to seepage can be accurately captured by the quasi-distributed FBG strain sensors.The test results also demonstrate that the slope stability is significantly affected by ground water seepage, which fits well with the results that were calculated using finite element and limit equilibrium methods.The relationship between the strain measurements and the safety factors is further analyzed, together with a discussion on the residual strains.The performance evaluation of a soil slope using fiber optic strain sensors is proved to be a potentially effective approach.
fiber optic sensor fiber Bragg grating (FBG) slope stability geotechnical monitoring model test soil strain measurement
Hong-Hu Zhu Bin Shi Jun-Fan Yan Jie Zhang Cheng-Cheng Zhang Bao-Jun Wang
School of Earth Sciences and Engineering,Nanjing University,Nanjing 210046,Peoples Republic of Chin Department of Geotechnical Engineering,Tongji University,Shanghai 200092,Peoples Republic of China
国际会议
南京
英文
443-454
2014-10-12（万方平台首次上网日期，不代表论文的发表时间）