Rock-fill dam panel void recognition device and recognition method

Abstract

The invention discloses a rock-fill dam panel void recognition device and recognition method, and belongs to the technical field of dam safety monitoring of water conservancy and hydropower engineering. The device comprises a rock-fill dam, a signal transmitting and transmitting mechanism and a signal receiving and measuring mechanism, a cushion layer is arranged on an upstream slope surface of a main rock-fill area of the rock-fill dam, a panel is arranged on the upstream slope surface of the cushion layer, one part of the signal transmitting and transmitting mechanism is arranged in the panel, and the other part of the signal transmitting and transmitting mechanism is arranged at the top of the rock-fill dam. One part of the signal receiving and measuring mechanism is arranged in the cushion layer, the other part of the signal receiving and measuring mechanism is located outside the cushion layer, and the two parts are in communication connection. The void deformation of the panel along the line from the construction period to the operation period can be recognized and positioned in time, and the influence of impounded water submerging is avoided; the acoustic signal sensing assembly is good in long-term stability and high in reliability, and the damage rate of the acoustic signal sensing assembly is reduced; the sound wave signal sensing assembly can be pulled out from the protection tube to replace the sound wave sensing optical fiber, and the later maintenance convenience of the sound wave signal sensing assembly is improved.

Description

Technical Field

[0001] The invention relates to a rockfill dam face plate hollowing identification device and identification method, belonging to the technical field of dam safety monitoring of water conservancy and hydropower engineering. Background Art

[0002] Under the influence of unfavorable factors such as excessive deformation of the dam body, uncoordinated deformation of the dam body and the rise and fall of the reservoir water level, the dam face plate may be hollowed out and deformed, which may cause cracks or even fractures, leading to serious leakage in the dam. Therefore, it is necessary to detect whether the face plate is hollowed out in time to ensure the safe operation of the project.

[0003] At present, there are usually two methods to identify whether the panel has hollowing deformation: one is to arrange hollowing meters at the key parts of the typical panel for long-term monitoring, and the other is to use geophysical exploration methods to conduct a comprehensive inspection of the panel regularly using geological radar. Although the hollowing meter can monitor the panel hollowing at the instrument arrangement point for long-term monitoring, it cannot reflect the distribution of hollowing deformation along the panel. The coverage is limited, resulting in the situation that the instrument is not arranged at the hollowing part of the panel and the part where the instrument is arranged is not hollowed in actual engineering application. At the same time, the hollowing meter is composed of two large-scale displacement meters. If one displacement meter is damaged, the whole set of hollowing meters will be scrapped, and there are problems of poor long-term stability and high damage rate of the instrument. The means of regular geophysical inspection are often carried out after the panel is cast and before the water is stored. After it is put into operation, it is difficult to inspect the panel under the reservoir water, and sometimes it is even necessary to empty the reservoir before it can be carried out, and the application conditions are limited. Moreover, geophysical inspection is mostly carried out after abnormal leakage is found in the dam, and long-term and continuous inspection cannot be achieved, and the role of advance warning cannot be played. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a rockfill dam face plate void identification device and identification method.

[0005] The present invention is achieved through the following technical solutions:

[0006] A rockfill dam panel void identification device comprises a rockfill dam, a signal transmitting and emitting mechanism and a signal receiving and measuring mechanism. A cushion layer is provided on the upstream slope of a main rockfill area of ​​the rockfill dam, a panel is provided on the upstream slope of the cushion layer, a part of the signal transmitting and emitting mechanism is provided in the panel, and another part is provided on the dam top of the rockfill dam, a part of the signal receiving and measuring mechanism is provided in the cushion layer, and another part is provided outside the cushion layer, and the two parts are communicatively connected.

[0007] The signal transmission mechanism includes an acoustic signal transmission component and an acoustic signal transmitting component. The acoustic signal transmission component is arranged in the panel, and the upper end of the acoustic signal transmission component extends to the top of the rockfill dam. The acoustic signal transmitting component is placed on the top of the rockfill dam.

[0008] The acoustic wave signal transmission component comprises a floral tube and a geotextile wound around the floral tube.

[0009] The sound wave signal transmitting component comprises a sine wave generator and a speaker, and the speaker is electrically connected to the sine wave generator.

[0010] The signal receiving and measuring mechanism comprises an acoustic signal receiving component and an acoustic signal detecting component. The acoustic signal receiving component is arranged in the cushion layer, and a part of the acoustic signal detecting component is arranged in the acoustic signal receiving component and the other part is arranged outside the acoustic signal receiving component.

[0011] The sound wave signal receiving component comprises a protection tube and a plurality of pickups arranged on the protection tube. All the pickups are arranged in a row in the axial direction of the protection tube, and the pickups are arranged toward a direction close to the panel.

[0012] The protection tube comprises a plurality of coaxially arranged PE tubes, and the pickup is connected to two adjacent PE tubes via a three-way joint.

[0013] The surface of the pickup is covered with geotextile.

[0014] The acoustic signal detection component comprises an acoustic signal sensing component and an acoustic fiber demodulator. The acoustic signal sensing component is arranged in the acoustic signal receiving component, and the acoustic fiber demodulator is communicatively connected with the acoustic signal sensing component.

[0015] The acoustic wave signal sensing component comprises a supporting tube and an acoustic wave sensing optical fiber which is equidistantly spirally wound and fixed on the supporting tube.

[0016] A method for identifying a rockfill dam face plate void identification device comprises the following steps:

[0017] Step 1: Before the panel reinforcement binding construction, place the acoustic signal sensor component into the acoustic signal receiving component, and then install the acoustic signal sensor component and the acoustic signal receiving component together into the cushion layer;

[0018] Step 2: Use an acoustic fiber demodulator to check whether the entire measurement line formed by the acoustic sensing optical fiber is intact, and then locate the position of the microphone to obtain the distance L0 of any microphone on the measurement line on the length of the acoustic sensing optical fiber;

[0019] Step 3: After the panel reinforcement is tied, fix the acoustic signal transmission component to the bottom reinforcement of the panel, and then pour the panel concrete;

[0020] Step 4: When the panel construction is completed, the panel and the cushion layer are well attached and no hollowing deformation has occurred. At this time, the acoustic signal transmitting component is used to send a fixed-frequency sinusoidal sound wave into the acoustic signal transmission component, and within the frequency range of 2000 Hz, the acoustic fiber demodulator is used to read the initial frequency value f0 along the acoustic sensor optical fiber, and then the initial frequency data is denoised and cleaned to obtain the initial frequency curve of the optical fiber before hollowing deformation occurs;

[0021] Step 5: At any time, use the acoustic signal transmitting component to send a sinusoidal sound wave with the same fixed frequency as in step 4 to the acoustic signal transmission component, and use the acoustic fiber demodulator to read the frequency value f along the acoustic sensor optical fiber at any time in real time within the frequency range of 2000 Hz. i , then the real-time frequency data is subjected to denoising and cleaning processing to obtain the real-time frequency curve of the optical fiber;

[0022] Step 6: Compare the real-time frequency curve of the optical fiber with the initial frequency curve of the optical fiber to identify whether the panel has been hollowed out and deformed.

[0023] The method of installing the acoustic wave signal sensing component and the acoustic wave signal receiving component together into the cushion layer in step 1 comprises the following steps:

[0024] Step A: excavating a trench on the upstream slope of the cushion layer, cleaning and leveling the inside of the trench, and manually compacting the bottom of the trench;

[0025] Step B, placing the acoustic signal sensing component and the acoustic signal receiving component into the groove together, and using an acoustic fiber demodulator to check whether the entire measuring line formed by the acoustic sensor optical fiber is intact;

[0026] Step C: backfill the trench with the same material as the cushion layer, and compact and level it.

[0027] In step 6, when the panel is hollowed out and deformed, the real-time distance L of all the pickups within the hollowing deformation range on the length of the acoustic wave sensing optical fiber is measured. i , to further evaluate the scope of the void deformation.

[0028] The beneficial effects of the present invention are:

[0029] 1. A fixed-frequency sinusoidal sound wave is sent through the sound wave signal transmitting component, the sound wave is transmitted through the sound wave signal transmission component, the sound wave is picked up by the sound wave signal receiving component, the sound wave is sensed by the sound wave signal sensing component, and then the sound wave frequency change is analyzed by the sound wave fiber optic demodulator, so as to realize the timely identification and positioning of the hollowing deformation along the panel from the construction period to the operation period, which is not affected by water storage and flooding; it solves the problem that the traditional hollowing meter monitoring method has limited coverage and cannot monitor the hollowing along the panel line, and the geophysical exploration method cannot give advance warning of hollowing deformation and cannot work underwater.

[0030] 2. Since the acoustic signal sensor assembly is completely enclosed in the protective tube, and the protective tube only has a hole at the pickup, the acoustic frequency f detected by the pickup 拾音器 It will be significantly amplified, which helps to ensure the accuracy of the acoustic signal detection component in identifying the panel's hollowing and deformation.

[0031] 3. The support tube wrapped with the acoustic wave sensing optical fiber is passed through the protective tube to protect the acoustic wave sensing optical fiber, thereby improving the long-term stability and reliability of the acoustic wave signal sensing component and reducing its damage rate. If the acoustic wave sensing optical fiber is damaged later, the support tube and the acoustic wave sensing optical fiber can be pulled out of the protective tube together, and then the acoustic wave sensing optical fiber can be replaced, thereby improving the convenience of later maintenance of the acoustic wave signal sensing component.

[0032] 4. It can not only identify panel hollowing and deformation, but also assess the scope of hollowing and deformation BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The present invention is a schematic diagram of the assembly structure of the cushion layer, panel, acoustic wave signal transmission component, acoustic wave signal receiving component and acoustic wave signal sensing component.

[0034] In the figure: 1- cushion layer, 2- acoustic wave sensing optical fiber, 3- pickup, 4- acoustic wave signal transmission component, 5- panel. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the description.

[0036] like Figure 1 As shown, a rockfill dam panel void identification device described in the present invention comprises a rockfill dam, a signal transmitting and emitting mechanism and a signal receiving and measuring mechanism. A cushion layer 1 is provided on the upstream slope of the main rockfill area of ​​the rockfill dam, a panel 5 is provided on the upstream slope of the cushion layer 1, a part of the signal transmitting and emitting mechanism is provided in the panel 5, and another part is provided on the dam top of the rockfill dam, a part of the signal receiving and measuring mechanism is provided in the cushion layer 1, and another part is located outside the cushion layer 1, and the two parts are communicatively connected.

[0037] The signal transmission mechanism includes an acoustic signal transmission component 4 and an acoustic signal transmitting component. The acoustic signal transmission component 4 is arranged in the panel 5, and the upper end of the acoustic signal transmission component 4 extends to the top of the rockfill dam. The acoustic signal transmitting component is placed on the top of the rockfill dam.

[0038] The acoustic signal transmission component 4 includes a flower tube and a geotextile wrapped around the flower tube. When in use, the flower tube is preferably made of a whole PE pipe. If it must be extended, the joint is sealed and fixedly connected; multiple holes are evenly processed on the PE pipe to form the flower tube, so that when the flower tube transmits sound waves, the sound waves are transmitted to the acoustic signal receiving component through the holes on the flower tube. Geotextile is wrapped around the outside of the flower tube to prevent soil and rocks from entering the flower tube and causing blockage. The projection of the flower tube on the upstream slope of the cushion layer 1 coincides with the projection of the protective tube on the upstream slope of the cushion layer 1.

[0039] The sound wave signal transmitting component comprises a sine wave generator and a speaker, and the speaker is electrically connected to the sine wave generator.

[0040] The signal receiving and measuring mechanism comprises an acoustic signal receiving component and an acoustic signal detecting component. The acoustic signal receiving component is arranged in the cushion layer 1, and a part of the acoustic signal detecting component is arranged in the acoustic signal receiving component and the other part is arranged outside the acoustic signal receiving component.

[0041] The acoustic signal receiving assembly includes a protective tube and a plurality of microphones 3 arranged on the protective tube, all of which are arranged in a row in the axial direction of the protective tube and are arranged toward the direction close to the panel 5. When in use, the upper end of the protective tube is closed.

[0042] The protective tube includes a plurality of coaxially arranged PE tubes, and the microphone 3 is connected to two adjacent PE tubes through a three-way joint. When in use, the microphone 3 is cylindrical, the bottom of which is connected to the three-way joint, the outer cylindrical surface is closed, and the top has a plurality of holes. The connection between the three-way joint and the PE tube and the microphone 3 is sealed, and the waterproof performance of the connection is not less than 1MPa. The microphone 3 picks up sound waves, which helps to ensure the recognition accuracy of the acoustic signal detection component for the hollowing deformation of the panel 5.

[0043] The surface of the pickup 3 is covered with a geotextile, which prevents soil and rocks from entering the pickup 3 and causing blockage.

[0044] The acoustic signal detection component comprises an acoustic signal sensing component and an acoustic fiber demodulator, wherein the acoustic signal sensing component is arranged in the acoustic signal receiving component, and the acoustic fiber demodulator is communicatively connected with the acoustic signal sensing component. When in use, the acoustic fiber demodulator is communicatively connected with the acoustic sensing optical fiber 2.

[0045] The acoustic wave signal sensing component includes a support tube and an acoustic wave sensing optical fiber 2 that is equidistantly spirally wound and fixed on the support tube. When in use, the support tube is also made of PE tube, and the support tube provides support for the acoustic wave sensing optical fiber 2, which is convenient for the equidistant spiral arrangement of the acoustic wave sensing optical fiber 2. The support tube wound with the acoustic wave sensing optical fiber 2 is inserted into the protective tube, and the protective tube is used to protect the acoustic wave sensing optical fiber 2, thereby improving the long-term stability and reliability of the acoustic wave signal sensing component and reducing its damage rate; if the acoustic wave sensing optical fiber 2 is damaged later, the support tube and the acoustic wave sensing optical fiber 2 can be pulled out of the protective tube together, and then the acoustic wave sensing optical fiber 2 can be replaced, thereby improving the convenience of later maintenance of the acoustic wave signal sensing component.

[0046] A method for identifying a rockfill dam face plate void identification device comprises the following steps:

[0047] Step 1: Before the panel reinforcement binding construction, place the acoustic wave signal sensing component into the acoustic wave signal receiving component, and then install the acoustic wave signal sensing component and the acoustic wave signal receiving component together into the cushion layer 1.

[0048] Step 2: Use an acoustic fiber demodulator to check whether the entire measuring line formed by the acoustic sensing optical fiber 2 is intact, then locate the position of the microphone 3 to obtain the distance L0 of any microphone 3 on the measuring line along the length of the acoustic sensing optical fiber 2.

[0049] Step 3: After the panel reinforcement is tied, fix the acoustic signal transmission component 4 to the bottom reinforcement of the panel 5, and then pour the panel concrete.

[0050] Step 4. When the construction of panel 5 is completed, panel 5 and cushion layer 1 are in good fit and no hollowing deformation has occurred. At this time, the acoustic signal transmitting component is used to send a sinusoidal sound wave of a fixed frequency to the acoustic signal transmission component 4, and within the frequency range of 2000 Hz, the acoustic fiber optic demodulator is used to read the initial frequency value f0 along the acoustic sensing optical fiber 2, and then the initial frequency data is denoised and cleaned to obtain the initial frequency curve of the optical fiber before hollowing deformation occurs.

[0051] Step 5: At any time, use the acoustic signal transmitting component to send a sinusoidal sound wave with the same fixed frequency as in step 4 to the acoustic signal transmission component 4, and use the acoustic fiber demodulator to read the frequency value f along the acoustic sensor optical fiber 2 at any time in real time within the frequency range of 2000 Hz. i , and then perform denoising and cleaning on the real-time frequency data to obtain the real-time frequency curve of the optical fiber.

[0052] Step 6: Compare the real-time frequency curve of the optical fiber with the initial frequency curve of the optical fiber to identify whether the panel 5 is hollowed out and deformed. When the panel 5 is hollowed out and deformed, the panel 5 at the hollowed-out part is separated from the cushion layer 1, so that the sound wave will be significantly changed when it propagates through the pickup 3 to the sound wave sensing optical fiber 2. At this time, by comparing the changes in the real-time frequency curve of the optical fiber with the initial frequency curve, it can be identified whether the panel 5 is hollowed out and deformed.

[0053] The method of installing the acoustic wave signal sensing component and the acoustic wave signal receiving component together into the cushion layer 1 in step 1 comprises the following steps:

[0054] Step A: dig a trench on the upstream slope of the cushion layer 1, clean and level the inside of the trench, and compact the bottom of the trench manually. When in use, the width of the trench × depth = 50 cm × 50 cm, and the length is determined according to the length of the protective tube.

[0055] Step B: Place the acoustic wave signal sensing component and the acoustic wave signal receiving component together in the groove, and use an acoustic wave optical fiber demodulator to check whether the entire measuring line formed by the acoustic wave sensing optical fiber 2 is intact.

[0056] Step C: backfill the trench with the same material as the cushion layer 1, and compact and level it.

[0057] In step 6, when the panel 5 is hollowed out and deformed, the real-time distance L of all the pickups 3 within the hollowing deformation range on the length of the acoustic wave sensing optical fiber 2 is measured. i , to further evaluate the range of the hollow deformation. For example, when there is only one pickup 3 within the hollow deformation range, the hollow deformation range is generally less than twice the distance between two adjacent pickups 3 when there is no hollow deformation; when there are two or more pickups 3 within the hollow deformation range, first measure the real-time distance L of all pickups 3 within the hollow deformation range on the length of the acoustic wave sensing optical fiber 2 i , and then calculate the real-time distance L between any two adjacent pickups 3 within the empty deformation range i Calculate the difference, finally add up all the differences and evaluate the range of the hollow deformation accordingly. Specifically, when the sound wave signal detection unit detects that the sound wave frequency suddenly changes at two or more consecutive pickups 3, it means that these pickups 3 are in the same hollow deformation range.

Claims

1. A rockfill dam face plate void identification device, characterized in that: The invention comprises a rockfill dam, a signal transmitting and signal receiving mechanism, wherein a cushion layer (1) is provided on the upstream slope of the main rockfill area of ​​the rockfill dam, a panel (5) is provided on the upstream slope of the cushion layer (1), a part of the signal transmitting and signal receiving mechanism is provided in the panel (5), and another part is provided on the top of the rockfill dam, and a part of the signal transmitting and signal receiving mechanism is provided in the cushion layer (1), and another part is provided outside the cushion layer (1), and the two parts are communicatively connected.

2. The rockfill dam face plate void identification device according to claim 1, characterized in that: The signal transmission mechanism comprises an acoustic signal transmission component (4) and an acoustic signal emission component. The acoustic signal transmission component (4) is arranged in the panel (5), and the upper end of the acoustic signal transmission component (4) extends to the top of the rockfill dam. The acoustic signal emission component is placed on the top of the rockfill dam.

3. The rockfill dam face plate void identification device according to claim 2, characterized in that: The acoustic wave signal transmission component (4) comprises a floral tube and a geotextile wrapped around the floral tube.

4. The rockfill dam face plate void identification device according to claim 2, characterized in that: The sound wave signal transmitting component comprises a sine wave generator and a speaker, and the speaker is electrically connected to the sine wave generator.

5. The rockfill dam face plate void identification device according to claim 1, characterized in that: The signal receiving and measuring mechanism comprises a sound wave signal receiving component and a sound wave signal detecting component. The sound wave signal receiving component is arranged in the cushion layer (1), and a part of the sound wave signal detecting component is arranged in the sound wave signal receiving component and another part is arranged outside the sound wave signal receiving component.

6. The rockfill dam face plate void identification device according to claim 5, characterized in that: The sound wave signal receiving component comprises a protective tube and a plurality of microphones (3) arranged on the protective tube, wherein all the microphones (3) are arranged in a row in the axial direction of the protective tube, and the microphones (3) are arranged in a direction close to the panel (5).

7. The rockfill dam face plate void identification device according to claim 6, characterized in that: The protective tube comprises a plurality of coaxially arranged PE tubes, and the pickup (3) is connected to two adjacent PE tubes via a three-way joint.

8. The rockfill dam face plate void identification device according to claim 6, characterized in that: The surface of the pickup (3) is covered with geotextile.

9. The rockfill dam face plate void identification device according to claim 5, characterized in that: The acoustic signal detection component comprises an acoustic signal sensing component and an acoustic fiber demodulator. The acoustic signal sensing component is arranged in the acoustic signal receiving component, and the acoustic fiber demodulator is communicatively connected with the acoustic signal sensing component.

10. The rockfill dam face plate void identification device according to claim 9, characterized in that: The acoustic wave signal sensing component comprises a support tube and an acoustic wave sensing optical fiber (2) which is equidistantly spirally wound and fixed on the support tube.

11. A recognition method for a rockfill dam face plate void recognition device according to any one of claims 1 to 10, characterized in that: The following steps are involved: Step 1: Before the panel reinforcement binding construction, the acoustic wave signal sensing component is placed in the acoustic wave signal receiving component, and then the acoustic wave signal sensing component and the acoustic wave signal receiving component are installed together in the cushion layer (1); Step 2: Use an acoustic fiber demodulator to check whether the entire measuring line formed by the acoustic sensing optical fiber (2) is intact, and then locate the position of the microphone (3) to obtain the distance L0 of any microphone (3) on the measuring line along the length of the acoustic sensing optical fiber (2); Step 3: After the panel reinforcement is tied, the acoustic signal transmission component (4) is fixed to the bottom reinforcement of the panel (5), and then the panel concrete is poured; Step 4: When the construction of the panel (5) is completed, the panel (5) and the cushion layer (1) are well attached and have not yet been deformed. At this time, a fixed-frequency sinusoidal sound wave is sent to the sound wave signal transmission component (4) by using the sound wave signal transmitting component, and within the frequency range of 2000 Hz, an acoustic fiber demodulator is used to read the initial frequency value f0 along the acoustic wave sensing optical fiber (2), and then the initial frequency data is subjected to denoising and cleaning processing to obtain the initial frequency curve of the optical fiber before hollowing and deformation; Step 5: At any time, use the acoustic signal transmitting component to send a sinusoidal sound wave with the same fixed frequency as in step 4 to the acoustic signal transmission component (4), and use the acoustic fiber demodulator to read the frequency value f along the acoustic sensor optical fiber (2) at any time in real time within the frequency range of 2000 Hz. i , then the real-time frequency data is subjected to denoising and cleaning processing to obtain the real-time frequency curve of the optical fiber; Step 6: Compare the optical fiber real-time frequency curve with the optical fiber initial frequency curve to identify whether the panel (5) has been hollowed out and deformed.

12. The identification method of the rockfill dam face plate void identification device according to claim 11, characterized in that: The method of installing the acoustic wave signal sensing component and the acoustic wave signal receiving component together in the cushion layer (1) in step 1 comprises the following steps: Step A, excavating a trench on the upstream slope of the cushion layer (1), cleaning and leveling the inside of the trench, and manually compacting the bottom of the trench; Step B, placing the acoustic wave signal sensing component and the acoustic wave signal receiving component together into the groove, and using an acoustic wave optical fiber demodulator to check whether the entire measuring line formed by the acoustic wave sensing optical fiber (2) is intact; Step C: backfill the trench with the same material as the cushion layer (1), and compact and level it.

13. The identification method of the rockfill dam face plate void identification device according to claim 11, characterized in that: In the step 6, when the panel (5) is deformed by hollowing out, the real-time distance L of all the pickups (3) within the hollowing out deformation range on the length of the acoustic wave sensing optical fiber (2) is measured. i , to further evaluate the scope of the void deformation.

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