Laboratory Studies on Slope Stability Monitoring Using Distributed Fiber-Optic Sensing Technologies

The advances in distributed fiber optic sensing (DFOS) technologies enable automatic, remote and long-distance slope monitoring and early-warning of potential geological disasters. Compared with conventional geotechnical instruments, the fiber optic sensors have a number of advantages such as higher accuracy and repeatability, better durability, and enhanced integration capability. In this paper, the quasi-distributed Fiber Bragg Grating (FBG) and fully-distributed Brillouin Optical Time-Domain Analysis (BOTDA) sensing technologies are applied for monitoring of slope stability problems in laboratory model tests. The sensing principles and the implementation methods are introduced, followed by two case studies. The fiber optic sensors were embedded in the model slopes for strain monitoring of a soil mass during seepage and surcharge loading, respectively. The reliability of the DFOS based slope monitoring systems has been verified through the analyses of the strain monitoring results.