Application Study of Distributed Optical Fiber Seepage Monitoring Technology on Embankment Engineering

Abstract

It is very important for embankment engineering to consider the seepage factor. If the potential seepage is not discovered in time and seepage control measures are not appropriate, seepage is very likely to cause damage and deformation, resulting in embankment failure. Based on temperature and seepage fields theories, a temperature–seepage coupled model is established in this paper. It is combined with a distributed temperature sensing (DTS) system to measure the temperature field of the porous media. This approach allows for the inversion of the inner seepage field, realizing the real-time monitoring of embankment health to ensure its safety and long-term operation. According to the coupling analysis on the temperature–seepage fields, for practical engineering, the influence of temperature on the seepage field is small and neglectable. Only the effect of the seepage field on the temperature field is considered. The DTS optical fiber temperature measurement system is widely used in various projects nowadays because of its high stability and efficiency advantages. The optical fiber is sensitive to temperature and can give fast and accurate temperature feedback regarding seepage location. Combined with the Heat Transfer Module in COMSOL, the multi-line heat source method can be used to invert the seepage field according to the temperature field of the porous medium inside the embankment and derive the seepage flow rate of the stable seepage field. For unstable seepage, optical fiber is good at seepage measuring and location detecting. For different practical engineering, a different heating power can be used for different seepage conditions. By monitoring the temperature change, the seepage condition can be inverted which is one of the indicators for evaluating engineering safety.

Keywords

• temperature field
• seepage field
• two-field coupling
• DTS
• finite element method