Soil dam seepage monitoring device

Abstract

The invention relates to a soil dam seepage monitoring device. A seepage temperature difference probe equipped with a heater, an upstream thermistor and a downstream thermistor is pre-embedded in a soil dam the seepage condition of which is to be monitored, a heating power supply switch is opened to heat the heater before monitoring, and after heating, if no seepage is monitored, the upstream thermistor and the downstream thermistor have consistent temperature rise and zero temperature difference owing to the symmetrical installation relation thereof, and a two-wire 4-20mA transmitter circuitoutputs 4mA, and if seepage is monitored, the seepage lowers the temperature of the upstream thermistor and raises the temperature of the downstream thermistor, the temperature difference between thetwo depends upon the seepage, i.e. the severer the seepage is, the larger the temperature difference is, and the corresponding two-wire 4-20mA transmitter circuit outputs the correspondingly increased current so as to indirectly determine the presence of seepage and the degree of the seepage. The device featured by directional monitoring is merely sensitive to the seepage jeopardizing the safety of dam and avoids erroneous alarm under the situation of general rainwater seepage, besides, the reliability is high and the adaptability is good.

Description

Technical field: [0001] The invention relates to a seepage monitoring device for soil dams, in particular to a device for monitoring seepage of soil dams through temperature changes. Background technique: [0002] According to statistics at home and abroad, more than 40% of dam failures are caused by seepage problems. Therefore, seepage has become one of the main contents of dam safety monitoring, and many complex detection devices have also been invented, including: Transient Electromagnetic Method (TEM) Dike leakage detectors; earth conductivity meters (frequency domain electromagnetic method, FEM); laying piezometers (pore water pressure gauges); ground penetrating radars and fiber optic sensors that simultaneously measure temperature and stress developed in recent years, etc. Nevertheless, the only one that can be rapidly popularized and widely used at present is the leakage water temperature detection method. The working principle is: when the permeability coefficient ...

AI Technical Summary

Problems solved by technology

However, due to the use of the natural temperature difference between water and soil, the size of the leakage temperature difference is directly affected by the external temperature change, resulting in changes in detection sensitivity, resulting in high or low reliability. The best period is from July to October in summer and autumn.

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