Experimental study on distributed optical fiber heated-based seepage behavior identification in hydraulic engineering

Abstract

The theoretical analysis and physical experiment on seepage behavior identification with distributed optical fiber temperature sensor system (DTS) are implemented. The distributed optical fiber-based approaches monitoring the seepage velocity and phreatic line in embankment dam or dike engineering are proposed. Firstly, the physical heat transfer process between optical fiber and porous material is analyzed. The basic principle identifying seepage behavior according to optical fiber temperature is presented. Secondly, a DTS-based test platform identifying seepage behavior in embankment dam or dike engineering is developed. Thirdly, the heat transfer coefficient in heat transfer theory is adopted to describe the heat transfer between optical fiber and saturated porous material. The experimental analysis for the relationship between overall heat transfer coefficient (i.e., the ratio of heating power and temperature rise) and seepage velocity is implemented. The mathematical model representing above relationship is built and an empirical method is given to monitor the seepage velocity in hydraulic engineering. Fourthly, the effect of moisture content on optical fiber temperature rise is analyzed by the experiment. The optical fiber arrangement plan is designed to monitor the phreatic line in embankment dam or dike engineering, the method is proposed to determine the position of phreatic line.