Acoustic emission damage monitoring apparatus and method for a concrete structure

Abstract

The application discloses a kind of acoustic emission damage monitoring device and method of concrete member, belong to acoustic wave detection technical field, including the first acoustic wave receiving sensor and second acoustic wave receiving sensor capable of being installed on the opposite sides of concrete member, still including two fixed plates oppositely arranged, the slide is opened in the fixed plate, the mounting plate is slidably connected in the slide, the screw hole is opened in the mounting plate, the outer sleeve is connected in the screw hole, the first acoustic wave receiving sensor or second acoustic wave receiving sensor is installed in the outer sleeve interior, the outer end of the outer sleeve is fixedly connected with the limit sleeve, the first scale rod is slidably connected in the limit sleeve.The application has the advantages of not needing several additional tools to cooperate, ensuring the vertical alignment of acoustic wave receiving sensor and concrete structure, and precise installation of position, improving the accuracy and reliability of detection data, solving the problems of prior art.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of acoustic wave detection, and particularly relates to an acoustic emission damage monitoring device and method for a concrete member. BACKGROUND

[0002] In the field of construction engineering, structural health monitoring technology assesses and predicts the health status of structures such as concrete members by real-time acquisition of physical parameters such as stress, strain and vibration, and plays a key role in ensuring structural safety and prolonging service life. Among them, the phenomenon that the stress in the local area of the material is concentrated, the energy is quickly released and the transient elastic wave is generated is called acoustic emission (AE), sometimes also called stress wave emission. The deformation and crack propagation of the material under stress are important mechanisms of structural failure. This source directly related to deformation and fracture mechanism is called acoustic emission source. As a passive health monitoring method, acoustic emission technology has the advantages of real-time monitoring, high sensitivity and wide coverage, and is widely used in the health monitoring of metals, composite materials, pressure vessels, bridges and aircraft structures, and can effectively early warn the risk of structural failure.

[0003] However, in the acoustic detection of concrete members, the traditional method has obvious drawbacks. In ultrasonic detection, the sound source is generated by the concrete structure during the damage process, and an acoustic receiving sensor is installed on the side wall of the concrete member to receive ultrasonic signals, but the installation position of the acoustic receiving sensor on the side wall of the concrete member has a significant impact on the detection results. For example, mark the corresponding measuring points on the surfaces of both sides of the member, and require the connecting line of the two points to be perpendicular to the surface, and then fix the acoustic receiving sensor with a clamp or a mechanical hand. This installation process not only requires the cooperation of several additional tools, but also is difficult to ensure the vertical alignment of the acoustic receiving sensor and the concrete structure, and the precise installation of the position, which affects the accuracy and reliability of the detection data, restricts the efficient application of acoustic emission technology in the damage monitoring of concrete members, and an improved monitoring device is urgently needed to solve the above problems. SUMMARY

[0004] In view of the problems in the prior art, the application provides an acoustic emission damage monitoring device and method for a concrete member, which has the advantages of not requiring the cooperation of several additional tools, ensuring the vertical alignment of the acoustic receiving sensor and the concrete structure, and the precise installation of the position, improving the accuracy and reliability of the detection data, and solving the problems of the prior art.

[0005] The application is achieved as follows: a damage monitoring device for acoustic emission of a concrete component, comprising a first acoustic wave receiving sensor and a second acoustic wave receiving sensor capable of being installed on opposite sides of the concrete component, and further comprising two oppositely arranged fixing plates, wherein a sliding channel is formed on each of the fixing plates, a mounting plate is slidably connected in the sliding channel, a screw hole is formed in the mounting plate, an external sleeve is connected to the screw hole, the first acoustic wave receiving sensor and the second acoustic wave receiving sensor are respectively installed in the external sleeve, and a limiting sleeve is fixedly connected to the outer end of the external sleeve, and a first scale rod is slidably connected in the limiting sleeve.

[0006] As preferred, limiting sliding grooves are formed on the upper and lower sides of the sliding channel, a plurality of first limiting blocks are arranged at equal intervals on the upper and lower sides of the mounting plate, the first limiting blocks are U-shaped blocks, one side of each of the first limiting blocks is slidably connected to the limiting sliding groove, and the other side of each of the first limiting blocks is slidably attached to the outer surface of the fixing plate.

[0007] As preferred, a plurality of limiting grooves are formed on the left side of the sliding channel, a first limiting plate is arranged in each of the limiting grooves, a third acoustic wave receiving sensor is fixedly connected to the first limiting plate, and a plurality of groups of second limiting blocks are fixedly connected to the first limiting plate, wherein one group of the second limiting blocks is clamped in the limiting sliding groove.

[0008] As preferred, the intervals of the first limiting blocks and the intervals of the limiting grooves are equal, the number of the first limiting blocks is equal to the number of the limiting grooves, and the size of the first limiting blocks is smaller than the size of the limiting grooves.

[0009] As preferred, an L-shaped fixing seat is fixedly connected to the end of the fixing plate away from the first limiting plate, a motor is fixedly connected to the L-shaped fixing seat, an output shaft of the motor is fixedly connected to a lead screw, the end of the lead screw is rotatably connected to the fixing plate, a second limiting plate is threadedly connected to the lead screw, the end of the second limiting plate is a semicircular surface, the semicircular surface is concentric with the lead screw, and the semicircular surface is attached to the L-shaped fixing seat.

[0010] A limiting seat is fixedly connected to the side of the second limiting plate away from the lead screw, a second scale rod is slidably connected in the limiting seat, and a fourth acoustic wave receiving sensor is threadedly connected to the second scale rod.

[0011] As preferred, the second limiting plate is fixedly connected to a first clamping block, the first clamping block is perpendicular to the second limiting plate, and the first clamping block is attached to the L-shaped fixing seat when the second limiting plate is arranged horizontally.

[0012] As the preferred of the present application, the second limiting plate is provided with a containing groove, the bottom of the containing groove is fixedly connected with an elastic piece, the elastic piece is fixedly connected with an L-shaped clamping block, and the L-shaped clamping block is slidingly connected to the containing groove.

[0013] The L-shaped clamping block is fixedly connected with a clamping block on one side, and the clamping block can clamp the second scale rod.

[0014] As the preferred of the present application, the first scale rod is slidingly provided with a limiting strip, the limiting strip is fixedly connected with rubber blocks arranged at equal intervals, and the rubber blocks can be clamped in the gaps between the first limiting blocks.

[0015] A method for monitoring damage of a concrete member by acoustic emission, using the acoustic emission damage monitoring device for the concrete member, comprising the following steps:

[0016] The fixed plate is transversely attached to the surface of the concrete member, the height of the fixed plate is measured by using the first scale rod vertically placed and the lower end abutting against the ground, and the height of the two fixed plates respectively installed with the first acoustic wave receiving sensor and the second acoustic wave receiving sensor is kept consistent by comparison and adjustment;

[0017] The first scale rod is rotated to a transverse state by rotating the outer screw sleeve, the position of the mounting plate in the sliding process of the slide is measured by the first scale rod, and the positions of the first acoustic wave receiving sensor and the second acoustic wave receiving sensor in the horizontal direction are determined;

[0018] The outer screw sleeve is screwed into the screw hole by continuously rotating the outer screw sleeve, and the first acoustic wave receiving sensor and the second acoustic wave receiving sensor are attached to the surface of the concrete member, and the installation is completed;

[0019] The damage of the concrete member is monitored by analyzing the signal data of each acoustic wave receiving sensor.

[0020] The step of monitoring the damage of the concrete member by analyzing the signal data of each acoustic wave receiving sensor comprises:

[0021] The acoustic emission signals generated when the concrete column is damaged are collected by each acoustic wave receiving sensor, and a group of intrinsic mode functions and a residual signal are obtained by decomposing and processing the acoustic emission signals;

[0022] The energy values presented in each intrinsic mode function are analyzed, and the effective intrinsic mode functions containing high-frequency energy are extracted; and the Hilbert marginal spectrum is obtained by signal transformation on all effective intrinsic mode functions;

[0023] The acoustic emission signals in the Hilbert marginal spectrum are screened to generate a specific frequency band of the Hilbert marginal spectrum; and the energy value corresponding to the specific frequency band is calculated according to the signal analysis of the specific frequency band.

[0024] Screening and extracting a plurality of acoustic emission signals between specific frequency bands from all acoustic emission signals, analyzing the energy value accumulation of the plurality of acoustic emission signals in any unit time, constructing an energy transformation function, and presenting the change process of the accumulated energy value of the plurality of acoustic emission signals;

[0025] Analyzing the energy value change process presented by the energy transformation function, identifying the mutation value appearing in the energy value accumulation process, and judging the fracture time of the CFRP tendon and strip of the concrete column for the generated mutation value.

[0026] CFRP is the abbreviation of Carbon Fiber Reinforced Polymer / Plastic, which is made of carbon fiber as reinforcing material and resin as matrix material, has the advantages of high strength, light weight, corrosion resistance, etc., and is often used for the reinforcement and enhancement of concrete structures, such as tendon or strip to improve the load-carrying capacity and durability of concrete members.

[0027] Compared with the prior art, the beneficial effects of the present application are as follows:

[0028] Firstly, the present application changes the traditional complex clamp or mechanical hand installation method, through the cooperation of the fixing plate, the mounting plate, the outer screw sleeve and the scale rod, the sensor installation process is more convenient, the installation difficulty and operation time cost are reduced. The double measurement of the first scale rod in the vertical and horizontal directions can accurately determine the position and height of the first and second sound wave receiving sensors, effectively ensure the vertical alignment of the two sensors and the concrete structure, and the accurate installation of the position, greatly improve the accuracy and reliability of the detection data.

[0029] Secondly, the outer screw sleeve and the sensor structure can be easily disassembled by unscrewing the outer screw sleeve, which is convenient for the maintenance, replacement and reuse of the sensor in the later stage, improves the practicality and economy of the device. When adjusting the position of the sensor, the sensor is not attached to the surface of the concrete member, which avoids damage to the sensor and the surface of the member during the adjustment process. After the position is determined, the outer screw sleeve is screwed in to realize the attachment, which makes the detection process more scientific and reasonable, and helps to improve the application effect of acoustic emission technology in concrete member damage monitoring. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a first perspective three-dimensional structure schematic diagram of the acoustic emission damage monitoring device for the concrete member provided by the embodiment 1 of the present application;

[0031] Figure 2 is an enlarged structure schematic diagram of part A in the embodiment 1 provided by the present application Figure 1 .

[0032] Figure 3 is a zoomed-in structural schematic view of part B in FIG. 1; Figure 1

[0033] Figure 4 is a zoomed-in structural schematic view of part C in FIG. 1; Figure 1

[0034] Figure 5 is a zoomed-in structural schematic view of part D in FIG. 1; Figure 1

[0035] Figure 6 is a perspective structural schematic view of the second view of the acoustic emission damage monitoring device for the concrete member provided in Embodiment 1 of the present application;

[0036] Figure 7 is a zoomed-in structural schematic view of part E in FIG. 1; Figure 6

[0037] Figure 8 is a top structural schematic view of the acoustic emission damage monitoring device for the concrete member provided in Embodiment 2 of the present application;

[0038] Figure 9 is a sectional structural schematic view of part F-F in FIG. 2; Figure 8

[0039] Figure 10 is a zoomed-in structural schematic view of part G in FIG. 2; Figure 9

[0040] Figure 11 is a perspective structural schematic view of the second view of the acoustic emission damage monitoring device for the concrete member provided in Embodiment 2 of the present application;

[0041] Figure 12 is a zoomed-in structural schematic view of part H in FIG. 2. Figure 11

[0042] ​​​​​​​In the diagram: 1. First acoustic wave receiving sensor; 2. Second acoustic wave receiving sensor; 3. Fixing plate; 4. Slide rail; 5. Mounting plate; 6. Screw hole; 7. External threaded sleeve; 8. Limiting sleeve; 9. First scale rod; 10. Limiting slide groove; 11. First limiting block; 12. Limiting groove; 13. First limiting plate; 14. Third acoustic wave receiving sensor; 15. Second limiting block; 16. L-shaped fixing seat; 17. Motor; 18. Lead screw; 19. Second limiting plate; 20. Limiting seat; 21. Second scale rod; 22. Fourth acoustic wave receiving sensor; 23. First locking block; 24. Receiving groove; 25. L-shaped locking block; 26. Clamping block; 27. Limiting strip; 28. Rubber block. Detailed Implementation

[0043] To further understand the invention's content, features, and effects, the following embodiments are provided, and detailed descriptions are given in conjunction with the accompanying drawings.

[0044] The structure of the present invention will now be described in detail with reference to the accompanying drawings.

[0045] Example 1

[0046] like Figures 1 to 7 As shown in the figure, an acoustic emission damage monitoring device for concrete components provided by an embodiment of the present invention includes a first acoustic wave receiving sensor 1 and a second acoustic wave receiving sensor 2 that can be installed on opposite sides of the concrete component, and two fixing plates 3 arranged opposite to each other. A slide rail 4 is provided on the fixing plate 3, and an mounting plate 5 is slidably connected in the slide rail 4. A screw hole 6 is provided inside the mounting plate 5, and an external threaded sleeve 7 is connected to the screw hole 6. The first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 are respectively installed inside the corresponding external threaded sleeve 7. A limit sleeve 8 is fixedly connected to the outer end of the external threaded sleeve 7, and a first scale rod 9 is slidably connected in the limit sleeve 8.

[0047] In use, first, the fixing plate 3 is horizontally attached to the surface of the concrete component. Using the vertically placed first scale rod 9 with its lower end resting on the ground, the height of the fixing plate 3 can be accurately measured. By comparison and adjustment, the two fixing plates 3, which respectively mount the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2, are kept at the same height. Next, the outer threaded sleeve 7 is rotated to make the first scale rod 9 rotate to the horizontal position. At this time, the first scale rod 9 can accurately measure the position of the mounting plate 5 during the sliding process of the slide rail 4, thereby accurately determining the horizontal position (i.e., left-right position) of the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2. After the position is determined, the outer threaded sleeve 7 is rotated further, and the outer threaded sleeve 7 screws into the threaded hole 6, causing the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 to adhere to the surface of the concrete component, completing the installation. After measurement, the operation can be reversed. If disassembly is required, the outer threaded sleeve 7 is rotated in the reverse direction to unscrew it, allowing the outer threaded sleeve 7 and the sensors and other structures mounted on it to be removed together. The operation is convenient.

[0048] It should be noted that when adjusting the positions of the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2, the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 are not in contact with the surface of the concrete component. After the positions are determined, the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 can be made to be in contact with the surface of the concrete component by screwing in the outer threaded sleeve 7.

[0049] Furthermore, the slide rail 4 has limiting grooves 10 on both its upper and lower sides, and the mounting plate 5 has several equidistant first limiting blocks 11 on both its upper and lower sides. Each first limiting block 11 is a U-shaped block, with one side slidably connected to the limiting groove 10 and the other side slidably attached to the outer surface of the fixing plate 3. The limiting grooves 10 on both sides of the slide rail 4 and the first limiting blocks 11 on the upper and lower sides of the mounting plate 5 form a sliding guide structure. The first limiting blocks 11 are equidistantly distributed and embedded in the limiting grooves 10. When the mounting plate 5 slides horizontally along the slide rail 4, the first limiting blocks 11 move along the grooves, ensuring the smoothness of the mounting plate 5's sliding and limiting the vertical displacement of the mounting plate 5 through the cooperation of the first limiting blocks 11 and the grooves. This prevents displacement during sensor installation and provides a stable mechanical reference for subsequent precise adjustment.

[0050] Further, the left side of the slide 4 is provided with a plurality of limiting grooves 12, wherein the limiting groove 12 is provided with a first limiting plate 13, the third sound wave receiving sensor 14 is fixedly connected to the first limiting plate 13, a plurality of groups of second limiting blocks 15 are fixedly connected to the first limiting plate 13, and one group of the second limiting blocks 15 is clamped in the limiting sliding groove 10. The first limiting plate 13 can be installed in different limiting grooves 12, so that it can be suitable for concrete members of different sizes. Since the third sound wave receiving sensor 14 is fixed to the first limiting plate 13, the position of the third sound wave receiving sensor 14 can be determined by the installation position of the second limiting plate 19. The installation position of the second limiting plate 19 can be determined by which second limiting block 15 is clamped in the limiting sliding groove 10. In summary, the first limiting plate 13 is clamped in the limiting groove 12 on the left side of the slide 4 through the second limiting block 15 thereon, and can be installed according to the size of the concrete member, realizing the adaptability of the device to members of different thicknesses. The third sound wave receiving sensor 14 is fixed to the first limiting plate 13, and its position is determined by the clamped limiting groove 12. The equidistant arrangement of the second limiting block 15 not only forms mechanical limiting for the first limiting plate 13, but also can directly read the transverse coordinates of the transmitter by observing the clamped position, having the functions of positioning and measurement.

[0051] Preferably, the interval of the plurality of first limiting blocks 11 is equal to the interval of the plurality of limiting grooves 12, the number of the plurality of first limiting blocks 11 is equal to the number of the plurality of limiting grooves 12, and the size of the plurality of first limiting blocks 11 is smaller than the size of the plurality of limiting grooves 12. Through this setting, when measuring, the first limiting block 11 cannot pass through the limiting groove 12 when the first limiting plate 13 is located in one of the limiting grooves 12, at which time the mounting plate 5 will not be detached. Conversely, when the measurement is completed and the limiting plate is removed, at this time the first limiting block 11 can pass through the limiting groove 12, at which time the mounting plate 5 and the first sound wave receiving sensor 1 and the second sound wave receiving sensor 2 thereon can be removed. In summary, the equidistant interval, equal number and size difference of the first limiting block 11 and the limiting groove 12 form an interlocking mechanism: when the first limiting plate 13 is clamped in a certain limiting groove 12, the first limiting block 11 is limited by the number of limiting grooves 12 and cannot be removed, ensuring that the mounting plate 5 will not be accidentally detached from the slide 4 during detection; after detection is completed, by adjusting the first limiting plate 13 to a specific position (such as the gap between the limiting grooves 12), the first limiting block 11 can smoothly pass through the groove body, realizing the quick disassembly of the mounting plate 5, balancing the structural stability and operational convenience.

[0052] Further, one end of the fixed plate 3 away from the first limiting plate 13 is fixedly connected with an L-shaped fixing seat 16, the L-shaped fixing seat 16 is fixedly connected with a motor 17, the output shaft of the motor 17 is fixedly connected with a lead screw 18, the end of the lead screw 18 is rotatably connected to the fixed plate 3, the lead screw 18 is threadedly connected with a second limiting plate 19, the end of the second limiting plate 19 is a semicircular surface, and the semicircular surface is concentric with the lead screw 18, and the semicircular surface is attached to the L-shaped fixing seat 16; the side of the second limiting plate 19 away from the lead screw 18 is fixedly connected with a limiting seat 20, the limiting seat 20 is slidably connected with a second scale rod 21, and the second scale rod 21 is threadedly connected with a fourth acoustic receiving sensor 22.

[0053] In use, the motor 17 on the L-shaped fixing seat 16 drives the lead screw 18 to rotate, driving the second limiting plate 19 to move linearly along the lead screw 18, realizing vertical height adjustment. In the initial state, the second limiting plate 19 and the second scale rod 21 are vertically arranged, and the scale rod bottom touches the ground to assist in measuring the height of the fixed plate 3; after the height is determined, the position of the second scale rod 21 can be adjusted according to the position of the third acoustic receiving sensor (by sliding the second scale rod 21 in the limiting seat 20), and then the position of the fourth acoustic receiving sensor 22 is determined, and then the second limiting plate 19 is rotated to the horizontal state, and the second scale rod 21 is synchronously rotated to the horizontal state. The fourth acoustic receiving sensor 22 is connected with the scale rod through threads, can be fine-tuned and fixed along the scale rod, ensures that the axes of the receiving and transmitting sensors are aligned, and receives signals. It should be noted that only one fourth acoustic receiving sensor 22 can be used as needed.

[0054] Further, the second limiting plate 19 is fixedly connected with a first clamping block 23, the first clamping block 23 is perpendicular to the second limiting plate 19, and when the second limiting plate 19 is horizontally arranged, the first clamping block 23 is attached to the L-shaped fixing seat 16. The first clamping block 23 is vertically fixed to the second limiting plate 19, one side of the first clamping block 23 is pressed against the surface of the concrete member when the second limiting plate 19 is vertically downward, forming a mechanical clamping force to assist the fixed plate 3 to adhere to the concrete member; when the second limiting plate 19 is rotated to the horizontal state for positioning of the fourth acoustic receiving sensor 22, one side of the first clamping block 23 is attached to the L-shaped fixing seat, thereby determining the horizontal position of the second limiting plate 19.

[0055] Further, a limiting strip 27 is slidably arranged on the first scale rod 9, equidistantly arranged rubber blocks 28 are fixedly connected to the limiting strip 27, and the rubber blocks 28 can be clamped in the gaps between the first limiting blocks 11.

[0056] The rubber blocks 28 on the limiting strip 27 of the first scale rod 9 realize positioning switching at different rotation angles:

[0057] Vertical state (initial installation): the rubber block 28 is clamped in the gap between the first limiting block 11 on the lower side and is attached to the fixed plate 3, and the scale rod is fixed in the vertical direction by using friction, which prevents the installation plate 5 from sliding and limits the first scale rod 9 to be in a vertical state, thereby improving the accuracy of detection.

[0058] Horizontal adjustment (horizontal positioning): the first scale rod 9 is rotated by 90°, the rubber block 28 is separated from the gap between the first limiting block 11, the restriction on the installation plate 5 is removed, and the installation plate 5 is allowed to slide freely along the slide 4. At this time, the first scale rod 9 can be used to accurately determine the left and right positions of the installation plate 5.

[0059] Working state (positioning completed): the first scale rod 9 is rotated by another 90° (cumulative 180°), the rubber block 28 is clamped in the gap between the first limiting block 11 on the upper side, and the outer sleeve 7 is screwed into the threaded hole 6 (0.5 thread pitch). Through the double action of the threaded pre-tightening force and the friction force of the rubber block 28, the position of the installation plate 5 is firmly locked, and displacement is avoided when the sensor is attached to the surface of the component.

[0060] Example 2

[0061] Different from example 1, this example does not use the first clamping block 23, but uses the following structure:

[0062] Referring to Figures 8-12 , the second limiting plate 19 is provided with a receiving groove 24, the bottom of the receiving groove 24 is fixedly connected with an elastic member, the elastic member is fixedly connected with an L-shaped clamping block 25, and the L-shaped clamping block 25 is slidingly connected in the receiving groove 24. One side of the L-shaped clamping block 25 is fixedly connected with a clamping block 26, and the clamping block 26 can clamp the second scale rod 21.

[0063] When the second limiting plate 19 is vertically downward, one side of the L-shaped clamping block 25 is pressed against the surface of the concrete component, forming a mechanical clamping force, which assists the fixed plate 3 in attaching to the concrete component. When the second limiting plate 19 is turned to a horizontal state for positioning the fourth acoustic wave receiving sensor 22, the L-shaped clamping block 25 and the L-shaped fixed seat are attached, the L-shaped clamping block 25 is pressed downward and at the same time presses the elastic member (such as a spring), and finally one side of the L-shaped clamping block 25 is attached to the L-shaped fixed seat, thereby limiting the second limiting plate 19 to a horizontal position. Moreover, in this process, the clamping block 26 is lowered, thereby clamping the second scale rod 21, and the position of the fourth acoustic wave receiving sensor 22 can be fixed.

[0064] Example 3

[0065] A method for monitoring the acoustic emission damage of a concrete component, which is suitable for the acoustic emission damage monitoring device of the concrete component, comprises the following steps:

[0066] The fixed plate 3 is transversely attached to the surface of the concrete member, the height of the fixed plate 3 is measured by the first scale rod 9 vertically placed and the lower end of which is grounded, and the height of the two fixed plates 3 respectively mounting the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 is kept consistent by comparison and adjustment;

[0067] The first scale rod 9 is rotated to the transverse state by rotating the outer screw sleeve 7, the position of the mounting plate 5 in the sliding process of the slide 4 is measured by the first scale rod 9, and the positions of the first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 in the horizontal direction are determined;

[0068] The first acoustic wave receiving sensor 1 and the second acoustic wave receiving sensor 2 are attached to the surface of the concrete member by continuing to rotate the outer screw sleeve 7, the outer screw sleeve 7 is screwed into the screw hole 6, and the installation is completed;

[0069] The damage of the concrete member is monitored by analyzing the signal data of each acoustic wave receiving sensor.

[0070] The step of monitoring the damage of the concrete member by analyzing the signal data of each acoustic wave receiving sensor includes:

[0071] The acoustic emission signals generated when the concrete column is damaged are collected by each acoustic wave receiving sensor, and a group of intrinsic mode functions and a residual signal are obtained by decomposing and processing the acoustic emission signals;

[0072] The energy values presented in each intrinsic mode function are analyzed, and the effective intrinsic mode functions containing high-frequency energy are extracted; and the Hilbert marginal spectrum is obtained by signal transformation on all effective intrinsic mode functions;

[0073] The acoustic emission signals in the Hilbert marginal spectrum are screened to generate a specific frequency band of the Hilbert marginal spectrum; and the energy value corresponding to the specific frequency band is calculated according to the signal analysis of the specific frequency band;

[0074] A number of acoustic emission signals between the specific frequency bands are screened and extracted from all acoustic emission signals, the energy value accumulation of the number of acoustic emission signals in any unit time is analyzed, an energy transformation function is constructed, and the change process of the accumulated energy value of the number of acoustic emission signals is presented;

[0075] The energy value change process presented by the energy transformation function is analyzed, and the sudden change value appearing in the energy value accumulation process is identified; and the fracture time of the CFRP tendon and strip of the concrete column is judged according to the generated sudden change value.

[0076] For details, please refer to the acoustic emission damage monitoring method for internal CFRP tendon and strip fracture disclosed in CN119715811A, which will not be repeated here.

[0077] The working principle of the present application is as follows:

[0078] First, the fixed plate 3 is transversely attached to the surface of the concrete member. The height of the fixed plate 3 can be accurately measured by using the first scale rod 9 which is vertically placed and the lower end of which is grounded. By comparison and adjustment, the heights of the two fixed plates 3 respectively installed with the first sound wave receiving sensor 1 and the second sound wave receiving sensor 2 are kept consistent. Then, the first scale rod 9 is rotated to the transverse state by rotating the outer screw sleeve 7. At this time, the first scale rod 9 can accurately measure the position of the installation plate 5 during the sliding process of the slide 4, so as to accurately determine the positions (i.e. left and right positions) of the first sound wave receiving sensor 1 and the second sound wave receiving sensor 2 in the horizontal direction. After the positions are determined, the outer screw sleeve 7 is continuously rotated, and the outer screw sleeve 7 is screwed into the screw hole 6, thereby driving the first sound wave receiving sensor 1 and the second sound wave receiving sensor 2 to be attached to the surface of the concrete member, and the installation is completed.

[0079] It should be noted that the relational terms herein such as first and second, and the like are used solely to distinguish one from another entity or action, without necessarily requiring or implying any such actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0080] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions, and alterations can be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. An acoustic emission damage monitoring device for a concrete structure comprising a first acoustic wave receiving sensor (1) and a second acoustic wave receiving sensor (2) mountable on opposite sides of a concrete structure, characterised in that: Also include two fixed plate (3) relative to the settings, the fixed plate (3) is provided with a slide (4), the slide (4) is slidably connected with the mounting plate (5), the mounting plate (5) is provided with a screw hole (6), the screw hole (6) is connected with the outer sleeve (7), the first sound wave receiving sensor (1) and the second sound wave receiving sensor (2) are respectively installed in the corresponding outer sleeve (7) inside, the outer end of the outer sleeve (7) is fixedly connected with a limiting sleeve (8), the limiting sleeve (8) is slidably connected with a first scale bar (9); The slide (4) is provided with a limiting sliding groove (10) on the upper and lower sides, the mounting plate (5) is provided with a plurality of first limiting blocks (11) which are equally spaced on the upper and lower sides, the first limiting block (11) is a U-shaped block, one side of the first limiting block (11) is slidably connected to the limiting sliding groove (10), and the other side is slidably attached to the outer surface of the fixed plate (3); The slide (4) is provided with a plurality of limiting grooves (12) on the left side, wherein the limiting groove (12) is provided with a first limiting plate (13), the first limiting plate (13) is fixedly connected with a third sound wave receiving sensor (14), and the first limiting plate (13) is fixedly connected with a plurality of groups of second limiting blocks (15) which are equally spaced, wherein one group of the second limiting blocks (15) is clamped in the limiting sliding groove (10); The spacing of a plurality of first limiting blocks (11) and the spacing of a plurality of limiting grooves (12) are equal, and the number of the first limiting blocks (11) and the number of the limiting grooves (12) are equal, and the size of the first limiting block (11) is smaller than the size of the limiting groove (12); The fixed plate (3) is fixedly connected with an L-shaped fixing seat (16) away from the first limiting plate (13), the L-shaped fixing seat (16) is fixedly connected with a motor (17), the output shaft of the motor (17) is fixedly connected with a lead screw (18), the end of the lead screw (18) is rotatably connected to the fixed plate (3), the lead screw (18) is threadedly connected with a second limiting plate (19), the end of the second limiting plate (19) is a semicircular surface, and the semicircular surface is concentric with the lead screw (18), and the semicircular surface is attached to the L-shaped fixing seat (16); The second limiting plate (19) is fixedly connected with a limiting seat (20) away from the lead screw (18), the limiting seat (20) is slidably connected with a second scale bar (21), and the second scale bar (21) is threadedly connected with a fourth sound wave receiving sensor (22).

2. A device for acoustic emission damage monitoring of a concrete member as claimed in claim 1, wherein: The second limiting plate (19) is fixedly connected with a first clamping block (23), the first clamping block (23) is perpendicular to the second limiting plate (19), when the second limiting plate (19) is horizontally arranged, the first clamping block (23) is attached to the L-shaped fixing seat (16).

3. A device for acoustic emission damage monitoring of a concrete structure as claimed in claim 1, wherein: The second limiting plate (19) is provided with a receiving groove (24), the bottom of the receiving groove (24) is fixedly connected with an elastic member, the elastic member is fixedly connected with an L-shaped clamping block (25), and the L-shaped clamping block (25) is slidably connected to the receiving groove (24). The L-shaped clamping block (25) is fixedly connected with a clamping block (26) on one side, and the clamping block (26) can clamp the second scale rod (21).

4. A device for acoustic emission damage monitoring of a concrete member as claimed in claim 2 or 3, wherein: A limiting strip (27) is slidably arranged on the first scale rod (9), and equidistantly arranged rubber blocks (28) are fixedly connected to the limiting strip (27), and the rubber blocks (28) can be clamped in the gaps between the first limiting blocks (11).

5. A method of acoustic emission damage monitoring of a concrete structure, characterized by, The acoustic emission damage monitoring device for the concrete member of any one of claims 1-4 comprises the following steps: The fixed plate (3) is transversely attached to the surface of the concrete member, the height of the fixed plate (3) is measured by the first scale rod (9) vertically placed and the lower end of which is grounded, and the height consistency of the two fixed plates (3) respectively installed with the first acoustic wave receiving sensor (1) and the second acoustic wave receiving sensor (2) is maintained by comparison and adjustment; The first scale rod (9) is rotated to a transverse state by rotating the outer screw sleeve (7), the position of the mounting plate (5) in the sliding process of the sliding rail (4) is measured by the first scale rod (9), and the positions of the first acoustic wave receiving sensor (1) and the second acoustic wave receiving sensor (2) in the horizontal direction are determined; The first acoustic wave receiving sensor (1) and the second acoustic wave receiving sensor (2) are attached to the surface of the concrete member by continuing to rotate the outer screw sleeve (7), and the outer screw sleeve (7) is screwed into the screw hole (6), and the installation is completed; The damage of the concrete member is monitored by analyzing the signal data of each acoustic wave receiving sensor.

6. A method of acoustic emission damage monitoring of a concrete member as claimed in claim 5, It is characterized in that: Among them, The step of monitoring the damage of the concrete member by analyzing the signal data of each acoustic wave receiving sensor comprises: The acoustic emission signals generated when the concrete column is damaged are collected by each acoustic wave receiving sensor, and a group of intrinsic mode functions and a residual signal are obtained by decomposing and processing the acoustic emission signals; The energy values presented in each intrinsic mode function are analyzed, and the effective intrinsic mode functions containing high-frequency energy are extracted; the Hilbert marginal spectrum is obtained by signal transformation of all effective intrinsic mode functions; The acoustic emission signals in the Hilbert marginal spectrum are screened to generate a specific frequency band of the Hilbert marginal spectrum; and the energy value corresponding to the specific frequency band is calculated according to the signal analysis of the specific frequency band; A number of acoustic emission signals between the specific frequency bands are screened and extracted from all acoustic emission signals, the energy value accumulation of the number of acoustic emission signals in any unit time is analyzed, an energy transformation function is constructed, and the change process of the cumulative energy value of the number of acoustic emission signals is presented; The energy value change process presented by the energy transformation function is analyzed, and the sudden change value appearing in the energy value accumulation process is identified; and the fracture time of the CFRP tendon and strip of the concrete column is judged according to the generated sudden change value.

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