Distributed optical fiber testing method for porous medium structure seepage

Abstract

The invention discloses a distributed optical fiber testing method for porous medium structure seepage. The method comprises the steps of: (1) constructing a porous medium structure model groove; (2) forming a uniform and steady seepage field; (3) conducting temperature monitoring on the target optical fiber embedded in the model groove; (4) carrying out ohmic heating operation on the target optical fiber; (5) measuring the temperature rise curves of different heating power under the steady seepage condition; (6) constructing a heat transfer equation of a total heat transfer coefficient of the optical cable; (7) representing the heat transfer between optical fiber and a seepage containing saturated porous medium by the total heat transfer coefficient; (8) measuring the temperature rise curves of different heating power under the condition of different seepage rates; and (9) monitoring the seepage rate. The method provided in the invention establishes an empirical relationship mathematical model of the seepage rate total heat transfer coefficient, accurately pinpoints the linear correlation between the seepage rate and an average total heat transfer coefficient, and reliably guarantees the monitoring precision.

Description

technical field [0001] The invention relates to a distributed optical fiber test device and method for percolation of a porous medium structure. Background technique [0002] The main problems faced by earth-rock dam projects in my country are leakage, piping, collapse, cracks, landslides, damage to slope protection, erosion and cavitation, etc. According to statistics, more than one-third of the damage in earth-rock dam projects is due to different degrees of seepage Leakage and various problems derived from leakage, more than 90% of embankment collapses are caused by leakage damage. [0003] A large amount of engineering experience shows that it is of great significance to strengthen the real-time positioning and quantitative monitoring of seepage and seepage deformation of earth-rock dams to ensure the safe operation of the project. The seepage problem of earth-rock dams has the characteristics of time-space randomness and concealment, and the initial magnitude is small. ...

AI Technical Summary

Problems solved by technology

However, the theory of this technology in the application of seepage monitoring is still immature, especially the quantitative relationship model between the temperature rise of optical fiber heating, seepage flow velocity, ambient temperature, and heating power has not been established. It is of great significance to develop seepage monitoring methods and devices

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