CN107794882B - A geomembrane that is convenient for large-area leakage detection and its leakage detection method - Google Patents

Abstract

The invention discloses a geomembrane which is convenient for large-area leakage detection. The electrodes form a pair, each electrode is connected to a corresponding wire, each wire is insulated from each other, and is attached to the surface of a single geomembrane, wherein the wire on each single geomembrane is connected to the circuit through a circuit branch line A bus, each single piece of geomembrane corresponds to a circuit branch line, and the terminal of the circuit bus is connected to the instrument panel and the external power supply; a leakage detection method of the geomembrane is also disclosed. The invention does not need to open the detection equipment all the time during leakage detection, effectively saves energy, and the detection equipment is integrated with the geomembrane, and the measured position can be adjusted only by rotating the shift knob during operation, and the operation and construction are convenient.

Description

A geomembrane that is convenient for large-area leakage detection and its leakage detection method

technical field

The invention relates to a geomembrane leakage detection technology, in particular to a geomembrane which is convenient for large-area leakage detection and a leakage detection method thereof.

Background technique

Geomembrane has the advantages of small permeability coefficient, large elongation rate, good environmental protection benefits (compared to concrete and clay materials), light weight and softness, easy construction, strong regional adaptability, high factory production quality assurance rate, and more convenient operation and maintenance. , In the field of anti-seepage, ranging from roof waterproofing to dam anti-seepage, geomembrane has a wide range of applications. And in recent years, with the development of geomembrane material science and the improvement of geomembrane performance, the application of geomembrane is more extensive, and the scale of use is getting larger and larger. In some large water conservancy projects, such as dams, reservoirs, embankments and other projects, the application prospect of geomembrane is very good. Geomembrane is more and more favored by the majority of engineers due to its advantages of easy construction, short construction period and low cost.

In the application of geomembrane in medium and low dams, the application technology is mature, the experience is rich, and the use effect is very good. Now the geomembrane is being developed for high dam applications. The Nam Ou River hydropower station in Laos, with a dam height of 85 meters, uses exposed composite geomembrane to prevent seepage. There are also many applications of geomembranes in reservoir seepage prevention. Here are just some examples: Liyang pumped storage power station, geomembrane is used for seepage prevention at the bottom of the upper reservoir, with a laying area of 250,000 m ² ; Taian pumped storage power station, The geomembrane at the bottom of the Shang Reservoir is anti-seepage, with a laying area of about 177,000 m ² ; the Datun Reservoir in the northern Lubei section of the eastern route of the South-to-North Water Diversion Project, a total of 5.01 million m ² of PE geomembrane is laid on the reservoir plate to prevent seepage; Mashan Pumped Storage Power Station, the bottom of the reservoir Geomembrane laying area is 235,000 m ² ; for Jurong Pumped Storage Power Station, the geomembrane area at the bottom of the reservoir is 491,000 m ² . It can be seen that in many projects, the use of geomembrane is very large, up to hundreds of thousands of square meters.

In the project using geomembrane in a large area, the problem of leakage detection of geomembrane during construction and operation is very prominent, which may be a very important factor restricting the use of geomembrane in a large area. Although there are many technologies for geomembrane leakage detection, such as: double electrode method, resistivity method (electrode grid method), high voltage direct current method, groundwater monitoring method, diffusion tube method, capacitive sensor method, tracer method, etc. However, these methods are mainly used to detect the leakage of geomembrane in a small area, and cannot effectively solve the leakage detection problem of large-area underwater geomembrane during operation. Although the distributed optical fiber temperature measurement technology can achieve large-scale temperature measurement, on the one hand, it is disturbed by the rising groundwater level, and on the other hand, it is expensive to use in a large area. The detection principle of the electrical method is to use the electrical insulation of the geomembrane and the conductivity of the liquid. If the geomembrane is not damaged, a current loop cannot be formed due to the insulation of the geomembrane, and no signal can be detected; if the geomembrane is damaged, the current will be A current loop is formed through the damage (hole), so that the electrical signal can be detected, and the hole can be located according to the distribution law of the detected signal. This method is currently very active in geomembrane leakage measurement, but no one has effectively applied it to large-area geomembrane leakage detection problems.

In the engineering of large-scale use of geomembrane such as anti-seepage at the bottom of the reservoir, after the reservoir is stored and operated, if the geomembrane is damaged somewhere and causes leakage, it is difficult to measure the damaged location of the geomembrane in time and effectively, which is extremely difficult. The earth limits the large-scale use of geomembrane.

SUMMARY OF THE INVENTION

Objects of the invention: The first object of the present invention is to provide a geomembrane that is convenient for large-area underwater leakage detection, and the second object is to provide a leakage detection method for the geomembrane.

Technical solution: The geomembrane of the present invention, which is convenient for large-area leakage detection, comprises a plurality of single geomembranes seamlessly spliced; the upper and lower surfaces of the single geomembrane are preset with a plurality of electrodes corresponding to two The electrodes form a pair, and each electrode is connected to a corresponding wire, and each wire is insulated from each other and attached to the surface of a single geomembrane, so that the geomembrane, the electrode and the wire become an organic whole. The wires on the single geomembrane are connected to the circuit bus through circuit branch lines, each single geomembrane corresponds to a circuit branch line, and the lines are insulated from each other, and the terminal of the circuit bus is connected to the instrument panel and the external power supply.

The connected instrument panel is provided with a plurality of rotary switches, each rotary switch is correspondingly connected to the circuit branch line of each single geomembrane, and the different gears of each rotary switch are correspondingly connected to different pairs on the single geomembrane. electrode.

At the same time, each rotary switch is provided with a positive and negative interface connected with an external power supply.

The purpose of using an external power source to energize a circuit of a pair of electrodes is achieved by rotating to different gears.

In order to make the wire attached to the geomembrane not affect the splicing between the two geomembranes, at the position where the wire passes through the splicing of the two geomembranes, a groove can be reserved for the geomembrane there during production, so that the wire can be embedded in the geomembrane. In the groove of the membrane, the welding of the geomembrane can not be affected.

Further, both sides of the single geomembrane are wrapped with geotextiles to protect the geomembrane.

At the same time, a quick and effective connection between the wires can be achieved through the conversion joint, and the wire is connected to the conversion joint. The conversion joint is composed of a protruding plug and a groove connector, which can realize the rapid and effective connection of the wires during construction.

The leakage detection method of the geomembrane that is convenient for large-area leakage detection includes the following steps:

(1) First, the geomembrane in the area to be detected is divided into multiple detection units by using the idea of breaking into parts, each detection unit consists of multiple single geomembranes, and each detection unit is connected to the instrument panel;

(2) Using the idea from coarse to fine, first make a rough leak judgment on the detection unit, set up a drainage channel in the detection unit, and determine whether the detection unit is leaking by measuring and analyzing the flow velocity and water pressure information in the drainage channel;

(3) Select the detection unit with leakage, and finely judge the leakage position. By connecting the external power supply to the rotary switch corresponding to each single geomembrane in the detection unit in turn, and by rotating the gear shift, select the correct position for the single geomembrane. Voltage is applied to different pairs of electrodes in the geomembrane, and the current test device is used to test whether the measured circuit corresponding to the pair of electrodes generates current, thereby conducting leakage detection. If current is generated, the corresponding pair of electrodes is the leakage position.

The step (2) is specifically as follows: setting a drainage channel such as a blind drain pipe in the detection unit, setting a leak detection device such as a velocity meter or a piezometer in the inside of the drain pipe, and transmitting the measured information by wired or wireless means. The information is transmitted to the information processing terminal, and the information is analyzed by the information processing terminal to determine whether there is leakage in the detection unit.

Beneficial effects: Compared with the prior art, the advantages of the present invention are as follows: (1) First, the geomembrane proposed by this patent has a self-detection function, and the detection equipment is organically combined with the geomembrane in advance during production in the factory. It not only effectively guarantees the quality, but also facilitates the construction; (2) Secondly, this patent uses the idea from coarse to fine, and realizes the detection of large-area geomembrane leakage in two steps, and it is not necessary to open all the detection equipment all the time. , which effectively saves energy; (3) This patent can easily apply voltage to different pairs of electrodes on a single geomembrane simply by rotating the shift knob, and the operation is very convenient.

Description of drawings

1 is a schematic diagram of the geomembrane structure of the present invention that is convenient for large-area leakage detection;

Fig. 2 is a partial enlarged view of the geomembrane of Fig. 1;

FIG. 3 is a plan view of a single geomembrane electrode of the present invention;

Fig. 4 is the cross-sectional schematic diagram of the single-width geotechnical form of the present invention;

5 is a schematic diagram of the circuit bus terminal instrument panel of the present invention;

6 is an enlarged view of the structure of a single geomembrane joint of the present invention;

FIG. 7 is a schematic diagram of a conversion joint at a line connection of the present invention.

Detailed ways

The technical solution of the invention will be further described below with reference to the accompanying drawings.

As shown in Figure 1 and Figure 2, the geomembrane that is convenient for large-area leakage detection includes seamless splicing of multiple single geomembranes 1; the geomembrane adopts 2.0mm thick HDPE geomembrane, and the single geomembrane 1 is wide 5m, 100m long, three rows of geomembrane constitute a detection unit 101, and each row has 5 single geomembrane 1.

As shown in Figures 3 and 4, 8 electrodes 2 are preset on the upper and lower surfaces of each single piece of geomembrane 1, corresponding to two electrodes 2 to form a pair, a total of 4 pairs, and the electrodes are ruthenium-plated titanium sheet electrodes. (diameter 50mm, thickness 1mm), each electrode 2 is connected to a wire 3 correspondingly, and each wire 3 is isolated by an insulating sheath, and attached to the surface of a single geomembrane 1, wherein each single geomembrane The wire 3 on the membrane 1 is connected to the circuit bus 5 through the circuit branch line 4, each single piece of geomembrane 1 corresponds to a circuit branch line 4, each detection unit 101 corresponds to a circuit bus 5, and the terminal of the circuit bus 5 is connected to the instrument panel 6 and an external power supply.

As shown in FIG. 5 , the instrument panel 6 is provided with a plurality of rotary switches 601 , and each rotary switch 601 corresponds to a circuit branch line connected to each single piece of geomembrane 1 .

The different gears of each rotary switch 601 are correspondingly connected to different pairs of electrodes 2 on a single geomembrane 1 .

Each of the rotary switches 601 is provided with a positive and negative electrode interface 602 connected to an external power source, and different pairs of electrodes can be adjusted by rotating the shift knob 603 for detection.

As shown in FIG. 6 , the connecting ends of the adjacent single geomembranes 1 are provided with grooves for embedding the wires 3 , and geotextiles 7 are wrapped and covered on both sides of the single geomembrane 1 .

As shown in FIG. 7 , the wire and the end of the wire are connected through a conversion joint 9 , which is formed by a combination of a protruding plug 901 and a groove connector 902 .

The leakage detection method of the geomembrane that is convenient for large-area leakage detection includes the following steps:

(1) Divide the geomembrane in the area to be detected into a plurality of detection units 101, each detection unit 101 includes a plurality of single geomembranes 1, and each detection unit 101 is connected to the instrument panel 6;

(2) The drain blind pipe 8 is arranged in the center of the detection unit 101, and the drain blind pipe 8 passes through the entire detection unit 101. At the same time, the drain blind pipe with smaller diameter is arranged at intervals of 10 m perpendicular to the drain blind pipe, in order to connect the detection unit 101 The leaking water in the area is led to the drainage dead pipe 8 for discharge. A flow meter or a piezometer is installed inside the drainage dead pipe 8, and the measured information of the flow rate and water pressure is transmitted to the information processing terminal, and the information is processed. Analyze to determine whether there is leakage in the detection unit 101;

(3) Select the detection unit with leakage, find the terminal instrument panel corresponding to the detection unit, select the rotary switch 601 corresponding to the single geomembrane 1 in turn, and connect the external power supply to the positive and negative corresponding to the rotary switch 601. At the pole interface 602, rotate the shift knob 603 in turn to apply voltage to different pairs of electrodes on a single geomembrane. If the circuit corresponding to a pair of electrodes is found to have current during power supply, it can be proved that there is seepage in the control range corresponding to the pair of electrodes. leak.

Claims (6)

1. A geomembrane that is convenient for large-area leakage detection is characterized in that: comprising being seamlessly spliced by a plurality of single geomembranes (1); the corresponding positions of the upper and lower surfaces of the single geomembrane (1) are preset. A plurality of electrodes (2) are provided, corresponding to two electrodes (2) to form a pair, each of the electrodes (2) is correspondingly connected to a wire (3), and each of the wires (3) is insulated from each other and attached to the The surface of the single geomembrane (1), wherein the wires (3) on each single geomembrane (1) are connected to the circuit bus (5) through the circuit branch line (4), and each single geomembrane (1) corresponds to A circuit branch line (4), the terminal of the circuit bus (5) is connected to the instrument panel (6) and the external power supply; the connecting end of the adjacent single-piece geomembrane (1) is provided with a recess for embedding the wire (3) The single geomembrane (1) is wrapped with geotextiles (7) on both sides, and the wire and the end of the wire are connected by a conversion joint, which is formed by a combination of a protruding plug and a groove connector. 2. The geomembrane for large-area leakage detection according to claim 1, characterized in that: the instrument panel (6) is provided with a plurality of rotary switches (601), and each rotary switch (601) is correspondingly connected The circuit branch of each single geomembrane (1). 3. The geomembrane convenient for large-area leakage detection according to claim 2, characterized in that: different gears of each rotary switch (601) are correspondingly connected to different pairs of electrodes on a single geomembrane (1). (2). 4. The geomembrane for large-area leakage detection according to claim 2, wherein each rotary switch (601) is provided with a positive and negative electrode interface (602) connected to an external power source. 5. the leakage detection method of the geomembrane that is convenient for large-area leakage detection described in claim 1 or 2 or 3 or 4, is characterized in that: comprise the following steps: (1) Divide the geomembrane in the area to be detected into a plurality of detection units, each detection unit includes a plurality of single geomembranes, and each detection unit is connected to the instrument panel; (2) Set up a drainage channel in the detection unit, and determine whether the detection unit leaks by measuring and analyzing the flow velocity and water pressure information in the drainage channel; (3) Select the detection unit with leakage, by sequentially connecting the external power supply to the rotary switch corresponding to each single geomembrane in the detection unit, and by rotating the gear shift, select the different pairs in the single geomembrane A voltage is applied to the electrodes, and a current test device is used to test whether the measured circuit corresponding to the pair of electrodes generates current, thereby performing leakage detection. 6. The leakage detection method of the geomembrane that is convenient for large-area leakage detection according to claim 5, wherein the step (2) is specifically: a drainage blind pipe (8) is arranged in the detection unit, and the A flow meter or a osmometer is arranged inside the drain blind pipe (8), and the measured information is transmitted to the information processing terminal, and the information is analyzed to determine whether there is leakage in the detection unit.

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