Tunnel segment defect nondestructive testing equipment and method based on impact echo method

Abstract

The invention relates to the technical field of tunnel construction, in particular to tunnel segment defect nondestructive testing equipment based on an impact echo method and a testing method.The testing equipment comprises a knocking detection device, the knocking detection device comprises a fixed mounting plate, a double-blade cam, a driver, a knocking rod, an energy storage part and a detection device, the fixed installation plate is installed on the carrying sliding platform in a sliding mode, the double-blade cam and the knocking rod are rotatably installed on the fixed installation plate, the first end of the knocking rod makes contact with the double-blade cam, the second end of the knocking rod is used for knocking a tunnel segment, and the driver drives the double-blade cam to rotate. The elastic piece is connected between the fixed mounting plate and one end, close to the double-blade cam, of the knocking rod, and the detection device is connected to the fixed mounting plate and is used for collecting sound wave signals. According to the invention, the technical problem that engineering application and accurate detection of internal defects of tunnel segments cannot be realized in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, and in particular to a nondestructive detection device and a detection method for tunnel segment defects based on an impact echo method. Background Art

[0002] Tunnel safety is the top priority of tunnel construction, and the shield segment of the tunnel is the main assembly component of the shield construction and the innermost barrier of the tunnel, which bears the role of resisting soil pressure, groundwater pressure and some special loads. The shield segment is the permanent lining structure of the shield tunnel. The quality of the shield segment is directly related to the overall quality and safety of the tunnel, and affects the waterproof performance and durability of the tunnel. Therefore, it is an important construction step to detect the integrity of the segment during the tunnel construction process, so as to detect defective or damaged segments and replace them.

[0003] Chinese patent CN117723637A discloses a tunnel contact detection system and a periodic shock wave excitation device thereof, and introduces a mechanical knocking device that drives a hammer to achieve periodic up and down reciprocating motion through a crank-connecting rod transmission mechanism and a slider driven by a motor. However, the device is not feasible in the actual working conditions of tunnel segment detection, and it is easy to cause the hammer to get stuck with the struck surface, the knocking is not in place, and effective sound signals cannot be obtained.

[0004] Chinese patent CN113125281A discloses an impact echo method for detecting a firing device, and introduces a knocking device that achieves equal intensity through a handle, an impact spring, a return spring, a height scale line, and a guide device. However, the device easily causes double-clicking and stagnation on the knocking surface, and generates a lot of interference signals to the sound signal, which is not conducive to the accuracy of subsequent results, and has a low degree of automation and intelligence.

[0005] Chinese patent CN112684003A discloses a mobile rapid detection device using an impact echo method, which introduces a simple hand-pushed trolley that drives a chain ball to rotate and collide with a concrete surface under the drive of a motor, and uses a microphone to collect sound signals. However, the steel ball of the device cannot produce an effective impact on the object being struck, which will inaccurate the detection result. Secondly, it cannot be used in the detection of tunnel segments.

[0006] Chinese patent CN112666255A discloses a system and method for rapid detection of shallow delamination of concrete bridge decks, which introduces the use of a drag chain excitation source and an acoustic signal acquisition device mounted on the end of a hand-pushed trolley. The device is only applicable to flat and shallow concrete surfaces and cannot be used on tunnel segments.

[0007] In summary, the existing detection devices all have problems such as knocking stagnation, double-clicking or inadequate knocking. They are only test institutions and cannot be combined with the actual working conditions of the project. Secondly, they cannot adapt to the knocking detection of defects in shield tunnel segments. They are inconvenient to operate and have a low degree of intelligence. The effective sound signal generated by knocking is not good, which will lead to inaccurate detection results or failure to detect defective tunnel segments. It is time-consuming and labor-intensive and cannot adapt to the current inspection and maintenance operation mode. Summary of the invention

[0008] The present invention aims to provide a nondestructive detection device and method for tunnel segment defects based on the impact echo method, so as to solve the technical problem that the detection device in the prior art cannot accurately detect the tunnel segment with defects. The specific technical solution is as follows:

[0009] The present invention provides a nondestructive detection device for tunnel segment defects based on the impact echo method, comprising:

[0010] A detection platform, the detection platform comprising a walking module;

[0011] A carrying sliding platform, wherein the carrying sliding platform is fixed on the detection platform;

[0012] A knocking detection device, which includes a fixed mounting plate, a double-leaf cam, a driver, a knocking rod, an energy storage member and a detection device. The fixed mounting plate is slidably mounted on the carrying sliding platform, the double-leaf cam and the knocking rod are rotatably mounted on the fixed mounting plate, the first end of the knocking rod contacts the double-leaf cam, the second end of the knocking rod is used to knock the tunnel segment, the driver drives the double-leaf cam to rotate, the energy storage member is connected between the fixed mounting plate and one end of the knocking rod close to the double-leaf cam, and the detection device is connected to the fixed mounting plate and is used for collecting sound wave signals.

[0013] A further improvement of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is that the detection device includes a sound collector, a sound collecting device and a connecting rod, the connecting rod is connected between the fixed mounting plate and the sound collector, the outer surface of the sound collector is provided with a sound insulation layer, the sound insulation layer can filter out interference signals, the sound collecting device is fixed at the focus of the sound collector to focus effective sound waves, and the sound collector is close to the second end of the knocking rod.

[0014] A further improvement of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is that the fixed mounting plate is provided with two cam mounting plates arranged opposite to each other, the double-leaf cam is rotatably mounted between the two cam mounting plates through a camshaft, and the driver is driven and connected to the camshaft.

[0015] A further improvement of the tunnel segment defect nondestructive testing equipment based on the impact echo method of the present invention is that the fixed mounting plate is provided with two relatively arranged knock rod mounting plates, and the knock rod is rotatably mounted between the two knock rod mounting plates through a knock rod shaft.

[0016] A further improvement of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is that a knocking head is provided at the second end of the knocking rod, and the knocking head can be replaced according to actual working conditions. However, the knocking head excites defects of different frequencies. An energy storage part is provided in the middle section of the knocking rod, and the energy storage part can drive the small bearing on the first end of the knocking rod through a double-leaf cam, so that the contact is smoother. When the double-leaf cam contacts the first end of the knocking rod and reaches a disengaged state, the energy storage part completes energy storage. When disengaged, the energy storage part forces the knocking head at the second end of the knocking rod to eject and impact the side surface. When the knocking head impacts the side surface for the second time, the double-leaf cam contacts the first end of the knocking rod to prevent the second end of the knocking rod from impacting the side surface multiple times, causing invalid signals to interfere with effective signals and aggravating the difficulty of subsequent data processing and analysis.

[0017] A further improvement of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is that the carrying sliding platform is ring-shaped, the number of the knocking detection devices is multiple, the fixed mounting plate is provided with a sliding drive part, and the multiple knocking detection devices are slidably installed on the arc fixed position of the carrying sliding platform through the fixed mounting plate, and the knocking detection devices can be automatically or manually arranged through the electronic control system.

[0018] A further improvement of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is that the walking module includes at least two moving wheel groups, the moving wheel groups are provided with a braking system and an encoding device, and the detection platform is provided with a driving system for driving the moving wheel groups to rotate.

[0019] A further improvement of the tunnel segment defect nondestructive testing equipment based on the impact echo method of the present invention is that it also includes an electric control system for performing electric control logic, and the electric control system is connected to the drive system and the driver.

[0020] A further improvement of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is that it also includes an operating system, which is connected to the driving system and the knocking detection device.

[0021] The present invention also provides a detection method for the tunnel segment defect non-destructive detection equipment based on the impact echo method as described above, comprising the following steps: controlling the knocking detection device to perform knocking operations through an operating system, the acquisition system receiving the original knocking sound wave signal, using time-frequency analysis technology, and using short-time Fourier transform type analysis signals in different time periods to extract useful features from complex signals, and combining the knocking position information and axial mileage information and simultaneously inputting them into a deep network model to process and analyze the characteristic signals of the knocking position, and finally classifying and counting the types, sizes and burial depths of tunnel segment defects, and giving accurate location information to each defect statistic.

[0022] A further improvement of the tunnel segment defect nondestructive testing equipment based on the impact echo method of the present invention is that it also includes a collection system for collecting pulse signals, video images and sound wave signals of the encoding device, and the collection system is connected to the operating system.

[0023] The application of the technical solution of the present invention has the following beneficial effects:

[0024] The structure of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is more reasonable, and the applicability of engineering applications is improved. By adjusting the angle between the knocking device and the measured surface, it can automatically separate from the side after colliding with the side under the action of gravity and the connection rhythm of the first end of the knocking rod and the double-leaf cam, and connect the knocking rod before the second knocking. It is not easy for jamming, virtual contact, double-clicking and other phenomena to interfere with the sound wave signal, and the positioning is more accurate. The data is directly associated with the mileage through pulse triggering collection and calculation of mileage, which is convenient for accurate positioning and later review. The sound collection system is assisted by a sound collector to operate, and a sound insulation layer is wrapped on the outside of the sound collector. The sound wave collection device is arranged at the focal position of the sound collector, which can collect effective sound waves and reduce the consumption of sound waves in the air. The sound insulation layer reduces the entry of external interference signals (especially in tunnels), which can effectively improve the accuracy of the operation results and solve the technical problem that the detection device in the prior art cannot accurately detect defective tunnel segments.

[0025] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0027] Figure 1It is a schematic diagram of the overall structure of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention;

[0028] Figure 2 It is a structural schematic diagram of a detection platform of a tunnel segment defect nondestructive detection equipment based on an impact echo method of the present invention;

[0029] Figure 3 It is a side view of a knock detection device of a tunnel segment defect nondestructive detection equipment based on an impact echo method of the present invention;

[0030] Figure 4 It is a stereoscopic diagram of a knock detection device of a tunnel segment defect nondestructive detection equipment based on an impact echo method of the present invention;

[0031] Figure 5 It is a transverse cross-sectional view of a detection device of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention.

[0032] Among them, 1. detection platform; 2. carrying sliding platform; 3. knocking detection device; 4. electronic control system; 5. acquisition system; 6. operating system; 7. seat; 8. body; 9. rear moving wheel group; 10. driving system; 11. front moving wheel group; 12. braking system; 13. encoding device; 14. auxiliary light; 15. fixed mounting plate; 16. cam mounting plate; 17. knocking rod mounting plate; 18. extension plate; 19. screw; 20. camshaft; 21. bearing; 22. double-leaf cam; 23. drive; 24. knocking rod; 25. contact wheel; 26. contact wheel shaft; 27. knocking rod shaft; 28. copper sleeve; 29. ​​bushing; 30. bearing; 31. knocking head; 32. elastic shaft; 33. energy storage part; 34. detection device; 35. connecting rod; 36. sound collector; 37. sound insulation layer; 38. sound collection device. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] See also Figure 1 to Figure 5 As shown, a non-destructive detection equipment for tunnel segment defects based on the impact echo method comprises:

[0035] The detection platform 1 includes a walking module, a vehicle body 8, and an auxiliary device;

[0036] A carrying sliding platform 2, wherein the carrying sliding platform 2 is fixed on the detection platform 1;

[0037] A knocking detection device 3, which includes a fixed mounting plate 15, a double-leaf cam 22, a driver 23, a knocking rod 24, an elastic member and a detection device 34. The fixed mounting plate 15 is slidably mounted on the carrying sliding platform 2, the double-leaf cam 22 and the knocking rod 24 are rotatably mounted on the fixed mounting plate 15, the first end of the knocking rod 24 contacts the double-leaf cam 22, the second end of the knocking rod 24 is used to knock the tunnel segment, the driver 23 drives the double-leaf cam 22 to rotate, the elastic member is connected between the fixed mounting plate 15 and one end of the knocking rod 24 close to the double-leaf cam 22, and the detection device 34 is connected to the fixed mounting plate 15 and is used to collect sound wave signals.

[0038] Specifically, Figure 3 and Figure 4 As shown, the fixed mounting plate 15 is L-shaped, including a horizontal plate and a vertical plate, and the horizontal plate is vertically fixed to the vertical plate. An elastic shaft 32 is provided near the first end of the knocking rod 24, which is used to connect the first end of the energy storage member 33, and the energy storage member 33 can be an elastic rope, a spring, etc. An opening is provided on the horizontal plate, and two ear plates are extended downward at the positions on both sides of the opening on the horizontal plate, and two vertical strip holes are correspondingly provided on the two ear plates, and a screw 19 is connected between the two strip holes. The second end of the energy storage member 33 is connected to the screw 19, and a scale line is engraved on the ear plate, and the position of the screw 19 on the strip hole can be adjusted according to actual needs, so as to adjust the tightness of the energy storage member 33, and then the scale position of the screw 19 is changed to change the size of the energy storage value of the energy storage member 33 to obtain the size of different knocking forces, and the consistency of the size of each knocking force can be ensured. The present invention can increase video monitoring, intelligent obstacle avoidance system and remote terminal control to realize unmanned operation.

[0039] The present invention can use a new energy drive motor to automatically travel, and the detection platform 1 can adaptively run along the rail or track line to perform knocking detection on the internal defects of the tunnel segment. It has the advantages of self-travel, one-time detection of the entire section, convenient operation, flexible operation mode, high intelligence, high detection accuracy, high efficiency, etc. The present invention will solve the current problems of difficulty in manual detection, inconvenient operation of large equipment, and high maintenance cost.

[0040] Preferably, Figure 5As shown, the detection device 34 includes a sound collector 36, a sound collecting device 38 and a connecting rod 35. The connecting rod 35 is connected between the fixed mounting plate 15 and the sound collector 36. The outer surface of the sound collector 36 is provided with a sound insulation layer 37. The sound collecting device 38 is fixed at the focus of the sound collector 36. The sound collector 36 is close to the second end of the knocking rod 24. The connecting rod 35 is mainly used to fix the detection device 34 on the fixed mounting plate 15. The vertical plate of the fixed mounting plate 15 is fixed with an extension plate 18 by bolts. The extension plate 18 is provided with a waist-shaped hole, which can be connected to the waist-shaped hole by bolts to adjust the position with the knocking head 31. In addition, a shaft sleeve 29 is sleeved on the connecting rod 35, and there is damping between the shaft sleeve 29 and the connecting rod 35. The sound collector 36 is fixed to one end of the connecting shaft sleeve. The height and angle position of the detection device 34 can be adjusted by adjusting the connecting shaft sleeve on the connecting rod 35, so that the detection device 34 is in the best position for collecting sound wave signals. The sound collection device is arranged at the focus of the sound collector 36, which can produce an energy-gathering and amplifying effect on the sound wave signal. The sound insulation layer 37 can be used to isolate external noise, reduce the interference of invalid sound waves on the detection data and the difficulty of subsequent data processing, and improve the detection accuracy and the reliability of the entire equipment.

[0041] Preferably, Figure 3 and Figure 4 As shown, the fixed mounting plate 15 is provided with two cam mounting plates 16 arranged opposite to each other, the double-leaf cam 22 is rotatably mounted between the two cam mounting plates 16 via a camshaft 20, and the driver 23 is drivingly connected to the camshaft 20. In this embodiment, the driver 23 is a servo motor, which can drive the double-leaf cam 22 to rotate periodically under the drive of the servo motor. The first end of the knocking rod 24 is provided with a contact wheel shaft 26, and a contact wheel 25 is installed on the contact wheel shaft 26, which contacts the double-leaf cam 22 through the contact wheel 25 to increase and reduce the friction during contact.

[0042] Preferably, the fixed mounting plate 15 is provided with two knocking rod mounting plates 17 arranged opposite to each other, and the knocking rod 24 is rotatably mounted between the two knocking rod mounting plates 17 via a knocking rod shaft 27. Furthermore, a copper sleeve 28 is provided between the knocking rod 24 and the knocking rod shaft 27, and a bearing 21 is provided between the knocking rod 24 and the knocking rod mounting plate 17 to improve the smoothness of the rotation of the knocking rod 24. The distance between the first end of the knocking rod 24 and the knocking rod shaft 27 is smaller than the distance between the second end of the knocking rod 24 and the knocking rod shaft 27.

[0043] Preferably, a knocking head 31 is provided at the second end of the knocking rod 24. The knocking head 31 can be replaced with a suitable size and material of the excitation size according to the required defect type. The knocking head 31 can be replaced with an embedded knocking head 31 with built-in pressure measurement, which is convenient for subsequent data processing, comparison and modeling analysis; the knocking device can use a non-contact excitation source (such as an air cannon) or a catapult collision to recover the impact ball for recycling.

[0044] Preferably, Figure 1 As shown, the carrying sliding platform 2 is annular, the number of the knock detection devices 3 is multiple, the fixed mounting plate 15 is provided with a sliding drive (the sliding drive can be a linear sliding component or a gear rack), and the multiple knock detection devices 3 are slidably installed on the arc position of the carrying sliding platform 2 through the fixed mounting plate 15. The carrying sliding platform 2 can be designed according to the tunnel interface size, the number of knock detection devices 3 can be determined according to the actual situation and the site conditions, the sliding drive can be driven by a motor, and the knock detection device 3 can be automatically and manually adjusted to its corresponding position on the carrying sliding platform 2 by a sliding motor (a camera device can be installed to adjust the position for manual viewing and adjustment), and can be deployed according to the actual site conditions to enhance the adaptability of the equipment. The detection of the same cross section can be completed once, which is more efficient, and a single knock detection device 3 can also be controlled separately to perform detection operations for review and detection. The carrying platform can arrange the knock detection mechanisms 3 in an array form, and can electrically control the relative positions of the knock detection mechanisms 3, adjust the deployment according to actual conditions, avoid some interference points, and be more in line with the actual engineering conditions; secondly, the detection of a cross section can be completed at the same time, which is more efficient.

[0045] Preferably, Figure 2As shown, the walking module includes at least two moving wheel groups, the moving wheel groups are provided with a braking system 12 and an encoding device 13, and the detection platform 1 is provided with a driving system for driving the moving wheel groups to rotate. The detection platform 1 also includes a vehicle body 8, and the walking module is installed at the bottom of the vehicle body 8. A seat 7 is provided on the vehicle body 8, and the seat 7 can carry an operator to remotely operate on site, which is more in line with the actual application of the project. The operator sits on the seat 7 and operates the operating system 6 to complete the forward stop and detection operation of the detection platform 1. The detection platform 1 is the installation and running base of the entire device. The moving wheel group includes a wheel pair and a frame. The driving system can provide driving power for the entire detection equipment. In this embodiment, there are two moving wheel groups, namely the front moving wheel group 11 and the rear moving wheel group 9. The front moving wheel group 11 is equipped with a braking system 12 and an encoding device 13. The braking system 12 can provide a braking function for the entire detection equipment to ensure that the entire equipment stops during the detection operation. The encoding device 13 is used to provide pulse counting for the entire equipment to calculate mileage and locate defects, and secondly for detection system pulse triggering collection. The auxiliary device includes an auxiliary light 14 installed at the front end of the detection platform 1. The auxiliary light 14 can improve the lighting and warning effects for the entire equipment during operation and operation.

[0046] Preferably, an electric control system 4 for performing electric control logic is also included, and the electric control system 4 is connected to the drive system and the driver 23. The electric control system 4 can control the drive system and the brake system 12, the auxiliary light 14, the rotation and stop of the motor, the power supply and communication of the electrical components, etc.

[0047] Preferably, it also includes an operating system 6, which is connected to the drive system and the knock detection device 3. The operating system 6 is used for the running start and stop operation, the auxiliary light 14 start and stop operation, the acquisition system 5 operation, the knock detection mechanism 3 operation, the video monitoring operation, etc. of the invention.

[0048] Preferably, it also includes a collection system 5 for collecting pulse signals, video images and sound wave signals of the encoding device, and the collection system 5 is connected to the operating system 6.

[0049] When in use, the double-leaf cam 22 is driven to rotate by the driver 23, and the knocking rod 24 contacts the double-leaf cam 22 through the contact wheel 25 to reach the highest point, so that the energy storage member 33 stores the maximum energy. When the double-leaf cam 22 is separated from the contact wheel 25, the knocking head 31 is ejected and collides with the detected surface under the action of the release of the energy storage member 33. After the collision, it can be immediately separated by self-generated gravity, and the first end of the knocking rod 24 is brought into contact with the double-leaf cam 22 in advance before the second contact, so as to avoid stagnation, jamming, virtual contact, and double-clicking of the knocking head 31 on the knocking surface, which will interfere with the effective sound waves and reduce the authenticity of the detection results. The detection device 34 installed on the fixed mounting plate 15 will collect the effective echo signal of the impact and store it in the storage card of the acquisition system 5 for subsequent processing and analysis of the detection data, and combined with the positioning of the encoding device, it is concluded that there are internal defects in the tunnel segment at a specific position, as well as the positioning of the internal defects in the tunnel.

[0050] The present invention proposes a detection platform 1 that can run smoothly along the track, which adopts lightweight materials and modular design; it is mainly composed of a front and rear running system, a carrying platform, a circular carrying sliding platform 2, a driving system, a braking system 12, an electronic control system 4, etc., to ensure that the detection platform 1 runs smoothly and adaptively along the track.

[0051] The present invention proposes a knocking detection mechanism 3, which is driven by a motor servo to control the knocking frequency. The knocking head 31 is a spherical knocking head 31 (the size of the spherical knocking head 31 can be replaced according to the detection requirements to meet different defect requirements). The knocking device is driven by a double-blade mechanism to drive the knocking rod 24 to eject and hit the concrete surface to be tested. After the knocking head 31 hits the concrete, it quickly separates from the concrete surface under the action of gravity, and makes the first end of the knocking rod 24 contact with the double-leaf cam 22 in advance before the second contact, which will not cause stagnation and double-clicking, and avoid the influence of echo interference waves and invalid waves.

[0052] The present invention proposes a data acquisition device, which is mainly composed of a sound collector 36 and a device for receiving sound waves, and collects effective signals to improve detection accuracy and reliability.

[0053] The fully automatic electric control system 4 of the present invention mainly includes automatic travel and braking of the detection platform 1, sliding of the knocking device, automatic knocking of the knocking device, data collection, etc. The present invention is easy to operate and can complete the detection of a ring section at one time without occupying public resources.

[0054] The operating system controls the detection platform to run to the detection position. The knocking detection device is controlled by the operating system to run along the annular slide rail to a pre-set position for layout, covering the detection of the entire cross-sectional area of ​​the tunnel. The on-site adjustment can be made through video images according to actual conditions to avoid interference areas; the knocking collection device is automatically controlled by the collection system 5, and the second end of the knocking rod 24 is driven by the double-leaf cam to knock on the surface of the tunnel segment. The collection system 3 focuses, amplifies and collects the knocking sound waves, and stores the collected data in the memory card of the host server of the electronic control system 4. The detection data is associated with the number of encoder pulses to facilitate subsequent defect analysis and precise positioning of the defect position. After completing the detection operation in the first area, the trolley can automatically or controlledly run to the second area for detection operations.

[0055] The present invention also provides a detection method for the tunnel segment defect nondestructive detection equipment based on the impact echo method as described above, comprising the following steps: controlling the knocking detection device (3) to perform a knocking operation through an operating system (6), receiving the original knocking sound wave signal through a collection system (5), using time-frequency analysis technology (the existing technology of a branch of bionics, using computer image visual analysis technology, by separating the background and the target in the scene and then analyzing and tracking the target in the camera scene), especially short-time Fourier transform (short-time Fourier transform, or short-termFourier transform, STFT, which is the existing technology) type analysis signal frequency information in different time periods, this method helps to extract useful features from complex signals, and combines the knocking position information (the coordinates of the knocking detection device on the tunnel segment section) and the axial mileage information (encoder pulse count) and simultaneously inputs them into a deep network model to process and analyze the characteristic signal of the knocking position, and finally classifies and counts the type, size and burial depth of the tunnel segment defects, and gives accurate position information to each defect statistic, which is convenient for subsequent inspection and maintenance operations. The deep network model can adopt deep neural network (DNN), convolutional neural network (CNN) or long short-term memory network (LSTM) as needed.

[0056] The structure of the tunnel segment defect nondestructive detection equipment based on the impact echo method of the present invention is more reasonable, and the applicability of engineering applications is improved. By adjusting the angle between the knocking device and the measured surface, the first end of the knocking rod 24 can be connected with the double-leaf cam 22 under the action of gravity, and it can automatically separate from the side after colliding with the side, and connect the knocking rod 24 before the second knocking. It is not easy for the phenomenon of jamming, virtual contact, double-clicking, etc. to interfere with the sound wave signal, and the positioning is more accurate. The data is directly associated with the mileage through pulse triggering collection and calculation of mileage, which is convenient for accurate positioning and later review. The sound collection system 5 is assisted by the sound collector 36, and a sound insulation layer 37 is wrapped on the outside of the sound collector 36. The sound wave collection device is arranged at the focal position of the sound collector 36, which can collect effective sound waves and reduce the consumption of sound waves in the air. The sound insulation layer 37 reduces the entry of external interference signals (especially in tunnels), which can effectively improve the accuracy of the operation results and solve the technical problem that the detection device 34 in the prior art cannot accurately detect defective tunnel segments.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A non-destructive testing device for tunnel segment defects based on the impact echo method, characterized in that: include: A detection platform (1), the detection platform (1) comprising a walking module; A carrying sliding platform (2), wherein the carrying sliding platform (2) is fixed on the detection platform (1); A knocking detection device (3), the knocking detection device (3) comprising a fixed mounting plate (15), a double-leaf cam (22), a driver (23), a knocking rod (24), an energy storage component and a detection device (34), the fixed mounting plate (15) being slidably mounted on the carrying sliding platform (2), the double-leaf cam (22) and the knocking rod (24) being rotatably mounted on the fixed mounting plate (15), the first end of the knocking rod (24) being in contact with the double-leaf cam (22), the second end of the knocking rod (24) being used for knocking a tunnel segment, the driver (23) driving the double-leaf cam (22) to rotate, the energy storage component being connected between the fixed mounting plate (15) and one end of the knocking rod (24) close to the double-leaf cam (22), and the detection device (34) being connected to the fixed mounting plate (15) and being used for collecting sound wave signals.

2. The nondestructive testing equipment for tunnel segment defects based on the impact echo method according to claim 1 is characterized in that: The detection device (34) comprises a sound collector (36), a sound collecting device (38) and a connecting rod (35); the connecting rod (35) is connected between the fixed mounting plate (15) and the sound collector (36); a sound insulation layer (37) is provided on the outer surface of the sound collector (36); the sound collecting device (38) is fixed at the focus of the sound collector (36); and the sound collector (36) is close to the second end of the knocking rod (24).

3. The tunnel segment defect nondestructive testing equipment based on the impact echo method according to claim 1 is characterized in that: The fixed mounting plate (15) is provided with two cam mounting plates (16) arranged opposite to each other, the double-leaf cam (22) is rotatably mounted between the two cam mounting plates (16) via a cam shaft (20), and the driver (23) is drivingly connected to the cam shaft (20).

4. The nondestructive testing equipment for tunnel segment defects based on the impact echo method according to claim 1 is characterized in that: The fixed mounting plate (15) is provided with two knocking rod mounting plates (17) arranged opposite to each other, the knocking rod (24) is rotatably mounted between the two knocking rod mounting plates (17) via a knocking rod shaft (27), and a knocking head (31) is provided at the second end of the knocking rod (24).

5. The tunnel segment defect nondestructive testing equipment based on the impact echo method according to claim 1 is characterized in that: The carrying sliding platform (2) is annular, the knock detection devices (3) are multiple in number, a sliding drive member is provided on the fixed mounting plate (15), and the multiple knock detection devices (3) are slidably mounted on the arc position of the carrying sliding platform (2) through the fixed mounting plate (15).

6. The tunnel segment defect nondestructive testing equipment based on the impact echo method according to claim 1 is characterized in that: The walking module comprises at least two moving wheel groups, the moving wheel groups are provided with a braking system (12) and an encoding device (13), and the detection platform (1) is provided with a driving system for driving the moving wheel groups to rotate.

7. The nondestructive testing equipment for tunnel segment defects based on the impact echo method according to claim 6 is characterized in that: It also includes an electric control system (4) for performing electric control logic, wherein the electric control system (4) is connected to the driving system and the driver (23) as well as the knocking and collection of the knocking detection device (3).

8. The tunnel segment defect nondestructive testing equipment based on the impact echo method according to claim 6 is characterized in that: It also includes an operating system (6), wherein the operating system (6) is connected to the driving system and the knock detection device (3).

9. The tunnel segment defect nondestructive testing equipment based on the impact echo method according to claim 8 is characterized in that: It also includes a collection system (5) for collecting pulse signals, video images and sound wave signals of the encoding device, and the collection system (5) is connected to the operating system (6).

10. A detection method using the tunnel segment defect nondestructive detection equipment based on the impact echo method as claimed in claim 9, characterized in that: The method comprises the following steps: controlling a knocking detection device (3) to perform a knocking operation through an operating system (6); receiving an original knocking sound wave signal through a collection system (5); using a time-frequency analysis technique and a short-time Fourier transform type to analyze the frequency information of the signal in different time periods, so as to extract useful features from complex signals; and combining the knocking position information and the axial mileage information and inputting them into a deep network model to process and analyze the characteristic signal of the knocking position. Finally, the type, size and burial depth of the tunnel segment defects are classified and counted, and accurate position information is given to each defect statistic.

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