Device suitable for detecting geomembrane defects at junction of dam face and reservoir basin

Abstract

The utility model discloses a device suitable for detecting geomembrane defects at the junction of a dam face and a reservoir basin, which comprises two detection plates hinged to each other, the included angle between the two detection plates is adjustable, each detection plate is uniformly connected with a plurality of detection electrodes at intervals, each detection electrode is connected to a data transmitter through a lead, and the data transmitter is connected with the dam face and the reservoir basin. And the data transmitter is wirelessly connected with the computer and is communicated with a power supply through a main lead. The utility model can solve the problem that the detection electrode and the bent geomembrane cannot be fully contacted when the existing detection plate detects the defects of the geomembrane at the junction of the dam surface and the reservoir basin, adopts the two hinged detection plates, and can detect the defects of the geomembrane by adjusting the included angle between the two detection plates according to the angle between the dam surface and the bottom of the reservoir basin. All the detection electrodes on the detection plate are in full contact with the geomembrane at the junction of the dam surface and the reservoir basin, so that full-coverage detection of the defects of the geomembrane at the junction of the dam surface and the reservoir basin can be realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of geomembranes, and in particular relates to a device suitable for detecting geomembrane defects at the junction of a dam surface and a reservoir basin. Background Art

[0002] Geomembrane is a new type of engineering anti-seepage material made of high molecular polymers, which has been widely used in dam anti-seepage and reservoir basin anti-seepage. Subject to the influence of manufacturing process and construction conditions, defects in geomembranes are inevitable. In a geomembrane anti-seepage reservoir with a full reservoir basin, when the geomembrane is laid on the dam surface and the bottom of the reservoir basin, the geomembrane at the junction of the dam surface and the reservoir basin is in a bent state, which is more prone to defects. Therefore, it is necessary to focus on the defects of geomembranes at the junction of the dam surface and the reservoir basin.

[0003] The double electrode method is usually used for defect detection of geomembranes. Its basic principle is that when positive and negative DC electrodes are buried on both sides of the geomembrane, no current loop will be formed when the insulating geomembrane is intact. When there is a defect in the geomembrane, the current flows into the soil layer under the membrane through the defect, forming a local abnormal potential distribution around the defect. The defect point of the geomembrane is inferred by the distribution of electrical parameters such as voltage and current between adjacent electrodes. When the double electrode method is used for defect detection of large-area anti-seepage geomembranes such as dams or reservoirs, in order to shorten the detection time, multiple detection electrodes are often jointly arranged on the detection board for regional detection, which can significantly improve the detection efficiency. However, at the junction of the dam surface and the reservoir, the geomembrane is in a bent state. The commonly used detection board cannot ensure full contact between the detection electrode and the bent geomembrane at the junction of the dam surface and the reservoir, which is easy to cause local loss or deviation of the detection data, resulting in reduced detection accuracy. Therefore, in order to ensure the detection accuracy of geomembrane defects at the junction of the dam surface and the reservoir, a high-precision geomembrane defect detection device suitable for the junction of the dam surface and the reservoir must be developed. Utility Model Content

[0004] The purpose of the utility model is to overcome the problem that conventional detection devices in the prior art cannot ensure sufficient contact between the detection electrode and the bent geomembrane, which easily causes local loss or deviation of geomembrane detection data at the junction of the dam surface and the reservoir basin, resulting in reduced detection accuracy, and to provide a device suitable for detecting geomembrane defects at the junction of the dam surface and the reservoir basin.

[0005] In order to solve the above technical problems, the utility model is implemented through the following technical solutions:

[0006] A device suitable for detecting geomembrane defects at the junction of a dam surface and a reservoir basin, comprising two detection plates hinged to each other, the angle between the two detection plates being adjustable, a number of detection electrodes being evenly spaced and connected to each detection plate, each detection electrode being connected to a data transmitter via a wire, the data transmitter being wirelessly connected to a computer, and the data transmitter being connected to a power source via a main wire.

[0007] By changing the hinge angle of the detection plate to adapt to the angle of the junction between the dam surface and the reservoir basin under different dam slope ratios, the detection electrode of the detection plate can be closely fitted to the surface of the geomembrane at the junction of the dam surface and the reservoir basin, and each detection electrode can fully contact the surface of the geomembrane. The detection electrodes are evenly arranged at each grid node of the detection plate, and the fixed electrodes are buried under the dam top. The detection electrodes and the fixed electrodes are energized to form a complete detection path. The grid line nodes on the detection plate are densely distributed, and the voltage measurement accuracy of each detection electrode is 0.001V. The data transmitter is used to transmit the position and measurement value of each detection electrode to the computer, and the computer automatically generates a potential map, and the location of the geomembrane defect is accurately determined by the potential map.

[0008] Specifically, the two detection boards are both made of insulating material and are plate-shaped structures with a certain thickness.

[0009] Preferably, the upper surface of each detection plate is divided into grid lines, and each intersection node of the grid lines has a detection electrode. The position of each detection electrode is a point with a certain coordinate value, which is convenient for observing and determining the defect position.

[0010] Preferably, at least one connecting member is fixedly connected to one end of the two detection plates that are hinged to each other. The connecting member includes a connecting tube and a connecting plate. The connecting tube and the connecting plate are fixedly connected. Bolts are inserted into the connecting tubes of the two detection plates, and the tail ends of the bolts are connected to nuts.

[0011] The bolt diameter is as close as possible to but smaller than the inner diameter of the connecting tube, so that the hinge structure is stable and does not loosen; lubricating oil is applied to the bolt before insertion, and the hinge structure of the device can be easily adjusted to a suitable angle according to the angle of the junction between the dam surface and the bottom of the reservoir basin.

[0012] Preferably, the connection between the connecting piece and the detection plate is detachable, a threaded hole is provided on the connecting plate, a matching threaded hole is provided at a corresponding position of the detection plate, and the connecting plate is connected to the detection plate by screws.

[0013] Preferably, the two detection plates have the same width, the length of the sleeve is slightly larger than half of the width of the detection plates, and when the sleeves of the two detection plates are connected end to end, the contact surface is located at the midline of the width direction of the detection plates.

[0014] The beneficial effects of the utility model are:

[0015] The utility model can solve the problem that when the existing detection plate detects geomembrane defects at the junction of the dam surface and the reservoir basin, the detection electrode and the bent geomembrane cannot fully contact each other. Two hinged detection plates are adopted. According to the angle between the dam surface and the bottom of the reservoir basin, the angle between the two detection plates is adjusted so that each detection electrode on the detection plate can fully contact with the geomembrane at the junction of the dam surface and the reservoir basin, thereby realizing full coverage detection of geomembrane defects at the junction of the dam surface and the reservoir basin.

[0016] A plurality of detection electrodes are precisely arranged on the detection board of the utility model according to the grid line nodes, the detection electrodes are densely distributed, the detection accuracy is high, the operation is convenient, and the practicability is strong. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The structure of the device located above the geomembrane at the junction of the dam surface and the reservoir basin is shown;

[0018] Figure 2 The planar structure of the device is shown;

[0019] Figure 3 The connection structure of the detection board 1 and the detection board 2 is shown;

[0020] Figure 4 The structure of the connector is shown;

[0021] Figure 5 The end view structure of the connector is shown;

[0022] Figure 6 The three-dimensional structure of the device is shown;

[0023] Figure 7 The application scenarios of the device are shown;

[0024] Figure numerals: 1, power supply; 2, detection electrode; 3, fixed electrode; 4, detection plate 1; 5, detection plate 2; 6, main wire; 7, bolt; 8, connecting piece 2; 9, connecting piece 1; 10, nut; 11, screw; 12, connecting tube; 13, connecting plate; 14, data transmitter; 15, computer. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods:

[0026] like Figure 1-6 As shown, a device suitable for detecting geomembrane defects at the junction of the dam surface and the reservoir basin includes a detection plate 1 4 and a detection plate 2 5. One end of the detection plate 1 4 and one end of the detection plate 2 5 are hinged to each other. The hinge structure is specifically as follows:

[0027] There is a connecting piece 9 at one end of the detection plate 1 4, and a connecting piece 2 8 at one end of the detection plate 2 5. The structures of the connecting piece 1 and the connecting piece 2 are the same, both including a connecting tube 12 and a connecting plate 13. The connecting tube 12 and the connecting plate 13 are fixedly connected by welding. The connecting tube 12 and the connecting plate 13 can also be an integrally formed structure. A threaded hole is provided on the connecting plate, and a matching threaded hole is also provided at the corresponding position of each detection plate. The connecting plate is installed on the corresponding detection plate together with the connecting tube by means of screws 11, and the axis of the sleeve is parallel to the edge line of the detection plate on which it is located.

[0028] For the convenience of description, Figure 3 The installation position of the connector is described in the up, down, left, and right directions of the middle view.

[0029] Connector 1 is close to the lower edge of detection plate 1, and connector 2 is close to the upper edge of detection plate 2. When the two detection plates are spliced ​​together, the axes of the two sleeves coincide. Bolt 7 passes through the two sleeves in sequence, and a nut 10 is connected to the tail end of bolt 7 to connect detection plate 1 and detection plate 2 together. Because there is a clearance fit between the sleeve and the bolt, the two detection plates can rotate around the bolt 7 through their respective sleeves to change the angle between the two detection plates.

[0030] In order to facilitate fixing the angle between the two detection plates and prevent the two detection plates from being misaligned, that is, the upper edge of detection plate one is flush with the upper edge of detection plate two, and the lower edge of detection plate one is flush with the lower edge of detection plate two, the two detection plates can be designed to have the same width, so that the length of the sleeve is slightly larger than half of the width of the detection plate, that is, when the two sleeves are spliced ​​end to end, the splicing surface is located at half of the width of the measuring plate, and the sum of the spliced ​​lengths is slightly larger than the width of the detection plate. By tightening the nut, the relative rotation between the two detection plates can be limited.

[0031] A number of mounting holes for mounting the detection electrode 2 are evenly spaced on each detection plate. The mounting holes penetrate the upper and lower surfaces of the detection plate (the mounting holes are not shown in the figure). The detection electrode is inserted into the mounting hole. The detection electrode and the mounting hole are interference fit to ensure that the detection electrode will not fall off or pass through the mounting hole during detection. The detection plate is made of insulating material. A wire is connected to the top of each detection electrode, and each wire is connected to a data transmitter 14. The data transmitter 14 integrates the same number of detection elements as the detection electrode, and each detection element has a unique number. Each detection element monitors the voltage and current signals in each detection electrode wire circuit. The data transmitter records the voltage and current signals of each detection element and transmits them wirelessly to the computer 15. The computer automatically receives the detection information and draws a potential diagram. The location of the geomembrane defect is determined based on the potential diagram. The computer is wirelessly connected to the data transmitter. The data transmitter is connected to the power supply 1 through the main wire 6, and the power supply energizes each detection electrode through the main wire and the data transmitter.

[0032] The data transmitter may be Toprie brand, model TP740. Drawing of potential diagram by computer and determination of the defect position of geomembrane according to the potential diagram are both existing technologies.

[0033] The size of the detection plate is designed to be small, 8cm×8cm square plate. The geomembrane is flat within a small range, so each detection electrode can be in close contact with the geomembrane during detection. The upper surface of each detection plate is divided into grid lines, each grid size is 1cm×1cm, and a detection electrode is set at the intersection node of each grid line. The detection electrodes are densely distributed, and the voltage measurement accuracy of each detection electrode is 0.001V. The dam slope ratio on the water storage side is generally small, and the spacing between the two rows of electrodes on both sides of the bolt is less than the spacing of the plane electrodes by 1cm, so there is no need to install electrodes at the junction line to cover the geomembrane at the junction line, and the accuracy is higher.

[0034] When in use, a fixed electrode 2 is buried in the soil below the geomembrane, the fixed electrode is connected to the power supply, the detection plate 2 5 is parallel to the bottom of the reservoir, the detection electrode on the detection plate 2 5 is in close contact with the geomembrane at the bottom of the reservoir, the nut 10 is loosened, and the detection plate 1 4 is slowly lowered until it is parallel and close to the dam surface; the nut 10 is tightened to keep the detection plate 1 4 and the detection plate 2 5 at a fixed angle. Turn on the power supply, energize each detection electrode, and the data transmitter detects, records and sends the monitoring data to the computer.

[0035] like Figure 7As shown, several areas to be detected can be horizontally delineated on the boundary line between the dam surface and the reservoir basin to detect defects in the geomembrane on the boundary line; because the bolts and nuts at the end of the device are slightly longer than the width of the detection plate, the width of a single detection area should be equal to the width of the detection plate, and there is no spacing between each adjacent area, so that after the previous detection is completed, the detection device can be moved to the right by the same distance as the width of the detection plate to start the next detection; the combination of data from several detections is the result of the geomembrane defect test on the boundary line.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device suitable for detecting geomembrane defects at the junction of dam surface and reservoir basin, characterized by: It includes two detection plates hinged to each other, the angle between the two detection plates is adjustable, and each detection plate is evenly spaced and connected with a number of detection electrodes, each detection electrode is connected to a data transmitter through a wire, the data transmitter is wirelessly connected to a computer, and the data transmitter is connected to a power source through a main wire.

2. The device for detecting geomembrane defects at the junction of the dam surface and the reservoir basin according to claim 1 is characterized by: Both detection boards are made of insulating material and are plate-like structures with a certain thickness.

3. The device for detecting geomembrane defects at the junction of the dam surface and the reservoir basin according to claim 1 is characterized by: The upper surface of each detection plate is divided into grid lines, and each intersection node of the grid lines is provided with a detection electrode.

4. The device for detecting geomembrane defects at the junction of the dam surface and the reservoir basin according to claim 1 is characterized in that: At least one connecting member is fixedly connected to one end of the two detection plates that are hinged to each other. The connecting member includes a connecting tube and a connecting plate. The connecting tube and the connecting plate are fixedly connected. Bolts are inserted into the connecting tubes of the two detection plates, and the tail ends of the bolts are connected to nuts.

5. The device for detecting geomembrane defects at the junction of the dam surface and the reservoir basin according to claim 4 is characterized in that: The connecting plate is provided with threaded holes, and the corresponding positions of the detection plate are provided with matching threaded holes, and the connecting plate is connected to the detection plate by screws.

6. The device for detecting geomembrane defects at the junction of the dam surface and the reservoir basin according to claim 4 is characterized by: The two detection plates have the same width, the length of the sleeve is slightly larger than half of the width of the detection plates, and when the sleeves of the two detection plates are connected end to end, the contact surface is located at the midline of the width direction of the detection plates.

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