Fiber optic bending loss sensor for application on monitoring of embankment dams

Abstract

We propose a fiber optic sensor system based on fiber bending loss and Optical Time Domain Reflectometry (OTDR) to application on monitoring of embankment dams. The sensing system was developed to monitor indirectly the water level penetration on the embankment dam by measuring the water pressure. The bend loss sensor performance was assessed concerning the number of fiber loops involved, the pump wavelength and temporal width of the pulse. Sensor system link is proposed to have a number of at least six sensors stages totally independent each other, in such a way that each stage can be developed to monitor a specific situation. In order to protect the sensor stage against environmental damage and to match the mechanical properties of the fiber and the water, we proposed a special packaging based on silicone rubber.