Acoustic emission detection experiment device and method for reinforced concrete slab under impact load effect

Abstract

The invention belongs to the technical field of civil engineering, and particularly relates to an acoustic emission detection experiment device and method for a reinforced concrete slab under the impact load effect, and the device comprises a frame, and the reinforced concrete slab is installed at the bottom of the frame; the weight is vertically and slidably connected to the frame, and the weight falls into the middle of the reinforced concrete slab to form an impact load; the lifting and releasing mechanism is arranged on one side of the frame, is in transmission connection with the heavy object and is used for releasing and lifting the heavy object; the detection assembly comprises a sound detection mechanism, a strain detection part, a displacement detection part and a photographing part; and the control and data acquisition mechanism is electrically connected with the detection assembly and located on one side of the frame. The invention further provides a detection method using the device. According to the method, key data including acoustic emission signals, displacement, deformation and the like can be comprehensively collected from multiple dimensions, and meanwhile, the material performance of the reinforced concrete slab is comprehensively evaluated by measuring the impact force.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering, and in particular relates to an acoustic emission detection experimental device and method for reinforced concrete slabs under impact load. Background Art

[0002] As a structural detection technology, acoustic emission technology is a non-destructive detection technology that can detect and locate damage inside the structure.

[0003] Reinforced concrete slabs are easily damaged under impact loads. Studying the damage caused by impact loads on reinforced concrete slabs will help the structural design of reinforced concrete slabs to ensure the long-term safety and durability of the structure.

[0004] Therefore, in order to facilitate the study of the damage caused by impact loads on reinforced concrete slabs, we propose an experimental device and method for acoustic emission detection of reinforced concrete slabs under impact loads. Summary of the invention

[0005] The purpose of the present invention is to provide an experimental device and method for acoustic emission detection of reinforced concrete slabs under impact loads to solve the above problems.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The experimental device for acoustic emission detection of reinforced concrete slabs under impact loads includes:

[0008] a frame, a reinforced concrete slab being mounted on the bottom of said frame;

[0009] A weight is vertically slidably connected to the frame, and the weight falls on the middle of the reinforced concrete slab to form an impact load;

[0010] A lifting and releasing mechanism is arranged on one side of the frame, the lifting and releasing mechanism is in transmission connection with the weight, and the lifting and releasing mechanism is used for releasing and lifting the weight;

[0011] A detection assembly, including an acoustic detection mechanism, a strain detection unit, a displacement detection unit, and a photographic unit;

[0012] The control and data acquisition mechanism is electrically connected to the detection component, and the control and data acquisition mechanism is located on one side of the frame.

[0013] Optionally, an impact head bracket is fixedly connected to the bottom of the frame, a reinforced concrete slab is fixedly connected to the bottom of the impact head bracket, an impact head is vertically slidably connected to the impact head bracket, a spoke-type force sensor is fixedly connected to the top of the impact head, and the bottom of the impact head is arranged in contact with the center of the surface of the reinforced concrete slab;

[0014] A pipeline for the sliding of the weight is provided in the middle of the impact head bracket, the impact head is located at the bottom end of the pipeline, and the weight hits the top of the impact head through the pipeline;

[0015] The spoke-type force sensor is electrically connected to the control and data acquisition mechanism.

[0016] Optionally, the lifting and releasing mechanism comprises:

[0017] An automatic wire retracting and releasing pulley assembly is arranged on the top of the frame. A steel wire rope is wound around the automatic wire retracting and releasing pulley assembly. One end of the steel wire rope is fixedly connected to the weight, and the other end of the steel wire rope is transmission-connected to a driving unit.

[0018] Optionally, the driving unit includes a winch, one end of the winch is fixedly connected to one end of the steel wire rope, and the winch is electrically connected to the control and data acquisition mechanism.

[0019] Optionally, the top axis of the pipeline is connected to the bottom end of a transparent pipe, and the transparent pipe is vertically slidably connected to the weight.

[0020] Optionally, the inner diameter of the transparent pipe matches the outer diameter of the weight.

[0021] Optionally, the acoustic detection mechanism includes a plurality of acoustic emission sensors, which are used to receive and record acoustic emission signals; the plurality of acoustic emission sensors are fixedly connected to the surface of the reinforced concrete slab, and the acoustic emission sensors are electrically connected to the control and data acquisition mechanism;

[0022] The strain detection unit includes a plurality of strain gauges, which are fixed to the reinforced concrete slab and are used to detect and record strain data, time data, resistance change of the strain gauge and voltage signal data when an impact load acts on the reinforced concrete slab;

[0023] The displacement detection unit includes a displacement meter, a fixed end of the displacement meter is fixedly connected to the frame, a movable end of the displacement meter is in contact with the bottom center of the reinforced concrete slab, and the displacement meter is used to detect the deformation amount of the reinforced concrete slab under the impact load;

[0024] The photographing unit includes a high-speed camera, which is arranged on one side of the frame and is used to photograph changes in the reinforced concrete slab surface and the speed and impact contact time of the heavy object when it impacts.

[0025] The displacement detection unit includes a displacement meter, a fixed end of the displacement meter is fixedly connected to the frame, a movable end of the displacement meter is in contact with the bottom center of the reinforced concrete slab, and the displacement meter is used to detect the deformation amount of the reinforced concrete slab under the impact load;

[0026] The photographing unit includes a high-speed camera, which is arranged on one side of the frame and is used to photograph changes in the reinforced concrete slab surface and the speed and impact contact time of the heavy object when it impacts.

[0027] Optionally, the control and data acquisition mechanism includes:

[0028] A PLC programmable controller, the PLC programmable controller is electrically connected to the acoustic emission sensor, the winch and the spoke-type force sensor, the PLC programmable controller is used to control the rotation of the winch, and the PLC programmable controller is used to receive feedback data from the acoustic emission sensor and the spoke-type force sensor.

[0029] Optionally, the PLC programmable controller is fixed to the ground via a PLC bracket.

[0030] An acoustic emission detection experimental method for reinforced concrete slabs under impact loads, using the above-mentioned acoustic emission detection experimental device for reinforced concrete slabs under impact loads, comprises the following steps:

[0031] Arranging the acoustic detection mechanism on a reinforced concrete slab;

[0032] installing a reinforced concrete slab on the bottom of the frame;

[0033] The control and data acquisition mechanism controls the lifting and releasing mechanism to lift the weight to a specified height, and then releases the weight. The weight impacts the middle of the reinforced concrete slab, and the control and data acquisition mechanism collects feedback data from the acoustic detection mechanism, the strain detection unit, the displacement detection unit and the photographic unit.

[0034] Compared with the prior art, the present invention has the following advantages and technical effects:

[0035] When in use, the acoustic detection mechanism is arranged on the reinforced concrete slab, and the reinforced concrete slab is installed at the bottom of the frame; the lifting and releasing mechanism is controlled by the control and data acquisition mechanism to lift the weight to a specified height, and then the weight is released, and the weight impacts the middle of the reinforced concrete slab, and the control and data acquisition mechanism collects feedback data from the acoustic detection mechanism, strain detection unit, displacement detection unit and photography unit. The present invention can comprehensively collect key data from multiple dimensions, including acoustic emission signals, displacement, deformation, etc., and at the same time, by measuring the impact force, a comprehensive evaluation of the material properties of the reinforced concrete slab is achieved. The control and data acquisition mechanism can control the entire test system, and each instrument can process the control task in real time to realize the automation of the test, and the operator can remotely control it in a safe position. In addition, the photography unit records the dynamic changes of the impact process, and the controllability of the experimental conditions allows the impact energy to be accurately adjusted. Overall, the method and device of the present invention not only improve the accuracy and repeatability of the experiment, but also have significant advantages in safety and economy, because it allows testing in a controlled environment, avoiding risks and losses in actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0037] Figure 1 It is the front view of the present invention;

[0038] Figure 2 It is a left side view of the present invention;

[0039] Figure 3 A top view of the present invention;

[0040] Among them, 1. frame; 2. automatic retractable wire pulley assembly; 3. heavy object; 4. transparent pipe; 5. PLC programmable controller; 6. PLC bracket; 7. impact head bracket; 8. high-speed camera; 9. wire rope; 11. acoustic emission sensor; 12. displacement meter; 13. winch. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] Reference Figures 1 to 3 The present invention discloses an acoustic emission detection experimental device for reinforced concrete slabs under impact load, comprising:

[0044] Frame 1, a reinforced concrete slab is installed at the bottom of frame 1;

[0045] The weight 3 is vertically slidably connected to the frame 1, and the weight 3 falls on the middle of the reinforced concrete slab to form an impact load;

[0046] A lifting and releasing mechanism is arranged on one side of the frame 1, the lifting and releasing mechanism is in transmission connection with the weight 3, and the lifting and releasing mechanism is used for releasing and lifting the weight 3;

[0047] A detection assembly, including an acoustic detection mechanism, a strain detection unit, a displacement detection unit, and a photographic unit;

[0048] The control and data acquisition mechanism is electrically connected to the detection component and is located on one side of the frame 1 .

[0049] When in use, the acoustic detection mechanism is arranged on the reinforced concrete slab, and the reinforced concrete slab is installed at the bottom of the frame 1; the lifting and releasing mechanism is controlled by the control and data acquisition mechanism to lift the weight 3 to a specified height, and then the weight 3 is released, and the weight 3 impacts the middle of the reinforced concrete slab, and the control and data acquisition mechanism collects the feedback data of the acoustic detection mechanism, the strain detection unit, the displacement detection unit and the photography unit. The present invention can comprehensively collect key data from multiple dimensions, including acoustic emission signals, displacement, deformation, etc., and at the same time, by measuring the impact force, a comprehensive evaluation of the material properties of the reinforced concrete slab is achieved. The control and data acquisition mechanism can control the entire test system, and each instrument can process the control task in real time to realize the automation of the test, and the operator can remotely control it in a safe position. In addition, the photography unit records the dynamic changes of the impact process, and the controllability of the experimental conditions allows the impact energy to be accurately adjusted. Overall, the method and device of the present invention not only improve the accuracy and repeatability of the experiment, but also have significant advantages in safety and economy, because it allows testing in a controlled environment, avoiding risks and losses in actual engineering.

[0050] As an optional embodiment, an impact head bracket 7 is fixedly connected to the bottom of the frame 1, a reinforced concrete slab is fixedly connected to the bottom of the impact head bracket 7, an impact head is vertically slidably connected to the impact head bracket 7, a spoke-type force sensor is fixedly connected to the top of the impact head, and the bottom of the impact head is arranged in contact with the center of the surface of the reinforced concrete slab;

[0051] A pipeline for the weight 3 to slide is provided in the middle of the impact head bracket 7, the impact head is located at the bottom end of the pipeline, and the weight 3 hits the top of the impact head through the pipeline;

[0052] The spoke-type force sensor is electrically connected to the control and data acquisition mechanism.

[0053] The reinforced concrete slab is fixed to the impact head bracket 7 according to the experimental requirements. This embodiment adopts the bottom support method of the reinforced concrete slab, and the support is provided at the bottom four corners of the reinforced concrete slab.

[0054] As an optional embodiment, the lifting and releasing mechanism includes:

[0055] The automatic retractable wire pulley assembly 2 is arranged on the top of the frame 1. A steel wire rope 9 is wound around the automatic retractable wire pulley assembly 2. One end of the steel wire rope 9 is fixedly connected to the weight 3, and the other end of the steel wire rope 9 is transmission-connected to a driving unit.

[0056] A frame 1 is constructed, and a crossbar is fixed in the middle of the top of the frame 1, and an automatic wire retracting and releasing pulley assembly 2 is rotatably arranged in the middle of the crossbar.

[0057] The automatic retractable wire pulley assembly 2 comprises at least one pulley, which is rotatably arranged in the middle of the crossbar.

[0058] Before the experiment begins, ensure that all steel tubes, crossbars and frame 1 structures have been adequately reinforced and inspected to withstand the forces and impacts that may occur in the experiment.

[0059] As an optional implementation, the driving unit includes a winch 13, one end of the winch 13 is fixedly connected to one end of the steel wire rope 9, and the winch 13 is electrically connected to the control and data acquisition mechanism.

[0060] As an optional implementation, the top axis of the pipeline is connected to the bottom end of the transparent pipe 4, and the transparent pipe 4 is vertically slidably connected to the weight 3.

[0061] As an optional implementation, the inner diameter of the transparent tube 4 matches the outer diameter of the weight 3 .

[0062] As an optional implementation, the acoustic detection mechanism includes a plurality of acoustic emission sensors 11, which are used to receive and record acoustic emission signals; the plurality of acoustic emission sensors 11 are fixedly connected to the top of the reinforced concrete slab, and the acoustic emission sensors 11 are electrically connected to the control and data acquisition mechanism;

[0063] The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 4 is characterized in that: the acoustic detection mechanism comprises a plurality of acoustic emission sensors (11), and the acoustic emission sensors (11) are used to receive and record acoustic emission signals; the plurality of acoustic emission sensors (11) are fixedly connected to the surface of the reinforced concrete slab, and the acoustic emission sensors (11) are electrically connected to the control and data acquisition mechanism;

[0064] The strain detection unit includes a plurality of strain gauges, which are fixed to the reinforced concrete slab. The strain gauges are used to detect and record strain data, time data, resistance change of the strain gauges and voltage signal data when the impact load acts on the reinforced concrete slab;

[0065] The displacement detection unit includes a displacement meter 12, the fixed end of the displacement meter 12 is fixedly connected to the frame 1, and the movable end of the displacement meter 12 is in contact with the bottom center of the reinforced concrete slab. The displacement meter 12 is used to detect the deformation amount of the reinforced concrete slab under the impact load;

[0066] The photographing unit includes a high-speed camera 8, which is arranged on one side of the frame 1. The high-speed camera 8 is used to shoot the changes in the reinforced concrete slab surface and the speed and impact contact time of the heavy object 3 when it impacts.

[0067] Strain gauges are attached to the surface of reinforced concrete slabs and the designed positions of internal steel bars. Strain gauges are used to understand the stress distribution of the structure under impact loads and evaluate the overall response of reinforced concrete slabs under impact loads.

[0068] The displacement detection unit includes a displacement meter 12, the fixed end of the displacement meter 12 is fixedly connected to the frame 1, and the movable end of the displacement meter 12 is in contact with the bottom center of the reinforced concrete slab. The displacement meter 12 is used to detect the deformation amount of the reinforced concrete slab under the impact load;

[0069] The photographing unit includes a high-speed camera 8, which is arranged on one side of the frame 1. The high-speed camera 8 is used to shoot the changes in the reinforced concrete slab surface and the speed and impact contact time of the heavy object 3 when it impacts.

[0070] Furthermore, the installation position of the acoustic emission sensor 11 is not fixed, and the acoustic emission signal can be received under different working conditions according to the experimental design. In this embodiment, preferably, four acoustic emission sensors 11 are fixedly connected to the reinforced concrete slab at equal intervals in the circumferential direction.

[0071] Before starting the experiment, make sure that the spoke force sensor has been calibrated and can accurately measure the force generated when the weight 3 falls.

[0072] The high-speed camera 8 should be set to clearly capture every detail of the impact process, including the fall of the weight 3, the impact moment and the subsequent dynamic changes.

[0073] As an optional implementation, the control and data acquisition mechanism includes:

[0074] PLC programmable controller 5, PLC programmable controller 5 is electrically connected with the acoustic emission sensor 11, the winch 13 and the spoke-type force sensor, the PLC programmable controller 5 is used to control the rotation of the winch 13, and the PLC programmable controller 5 is used to receive feedback data from the acoustic emission sensor 11 and the spoke-type force sensor.

[0075] As an optional implementation, the PLC programmable controller 5 is fixed to the ground via a PLC bracket 6 .

[0076] Ensure that all devices are properly connected to the PLC programmable controller 5 and that the PLC programmable controller 5 has been configured to synchronously record the data of the force sensor, acoustic emission sensor 11 , strain gauge and displacement meter 12 .

[0077] An acoustic emission detection experimental method for reinforced concrete slabs under impact loads, using the above-mentioned acoustic emission detection experimental device for reinforced concrete slabs under impact loads, comprises the following steps:

[0078] Arranging the acoustic detection mechanism on the reinforced concrete slab;

[0079] Install the reinforced concrete slab at the bottom of frame 1;

[0080] The lifting and releasing mechanism is controlled by the control and data acquisition mechanism to lift the weight 3 to a specified height, and then the weight 3 is released. The weight 3 impacts the middle of the reinforced concrete slab, and the control and data acquisition mechanism collects feedback data from the acoustic detection mechanism, strain detection unit, displacement detection unit and photography unit.

[0081] The test process refers to the following steps:

[0082] 1) Build the experimental framework 1 of required height according to the experimental design;

[0083] 2) installing an acoustic emission sensor 11 on the reinforced concrete slab according to the experimental design position to receive and record the acoustic emission signal;

[0084] 3) Install strain gauges on the reinforced concrete slab according to the experimental design position to record the strain information of the slab surface under impact load;

[0085] 4) Install a displacement meter 12 at the bottom of the reinforced concrete slab to record the deformation of the slab under the impact load;

[0086] 5) A high-speed camera 8 is placed on the right side of the frame 1 to record the impact speed, impact contact time and deformation of the reinforced concrete slab surface;

[0087] 6) Install a spoke-type force sensor on the contact surface between the weight 3 used for impact and the reinforced concrete slab to obtain the accurate force during impact;

[0088] 7) Connect each device to the PLC programmable controller 5;

[0089] 8) Using the steel wire rope 9 to fix the weight 3 on the automatic retractable wire pulley assembly 2;

[0090] 9) A transparent pipe 4 is fixed on the falling path of the weight 3, i.e., above the impact position, to ensure that the impact position does not deviate;

[0091] 10) The wire rope 9 is operated by the system to pull the weight 3 to a predetermined height. After the weight 3 is stable, the wire rope 9 is released, and the weight 3 impacts the spoke-type force sensor through the transparent pipe 4;

[0092] 11) Use the PLC programmable controller 5 to receive and record the test data of each device.

[0093] (S1) Build the experimental device: 1) Build the frame 1; 2) A horizontal bar is fixed in the middle of the top of the frame 1; 3) An automatic retractable wire pulley assembly 2 is fixed in the middle of the top horizontal bar; 4) A weight 3 is set and suspended on the automatic retractable wire pulley assembly 2 by a steel wire rope 9; 5) A spoke force sensor is installed at the bottom of the weight 3; 6) A transparent straight tube with a diameter slightly larger than the weight 3 is fixed between the weight 3 and the reinforced concrete slab, at the upper part of the falling path of the weight 3, i.e., the impact position; 7) The reinforced concrete slab is fixed at the center of the bottom of the frame 1 as required; 8) According to the experimental design, the acoustic emission sensor and the strain gauge are fixed around the impact position of the reinforced concrete slab; 9) A displacement meter 12 is installed at the bottom of the reinforced concrete slab; 10) A high-speed camera 8 is placed on one side of the frame 1; 11) The PLC programmable controller 5 is configured and each device is connected to the PLC programmable controller 5;

[0094] (S2) According to the experimental design, the PLC programmable controller 5 is used to control the entire test system, perform a cyclic same load impact test or a load increasing impact test, and receive test data of each device;

[0095] (S3) Receive and record the acoustic emission signal through the acoustic emission sensor 11; record the stress distribution and overall response of the board surface under the impact load through the strain gauge; record the deformation of the board under the impact load through the displacement meter 12 installed at the bottom; record the dynamic changes such as the speed, impact contact time and board surface deformation during the impact through the high-speed camera 8; obtain the accurate force during the impact through the spoke force sensor; and ensure that the impact position does not shift through the transparent pipe 4. Use the PLC programmable controller 5 to control the entire test system and receive the experimental data of each device.

[0096] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0097] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. Experimental device for acoustic emission detection of reinforced concrete slab under impact load, characterized by: include: A frame (1), a reinforced concrete slab mounted on the bottom of the frame (1); A heavy object (3) is vertically slidably connected to the frame (1), and the heavy object (3) falls on the middle of the reinforced concrete slab to form an impact load; A lifting and releasing mechanism is arranged on one side of the frame (1), the lifting and releasing mechanism is in transmission connection with the weight (3), and the lifting and releasing mechanism is used for releasing and lifting the weight (3); A detection assembly, including an acoustic detection mechanism, a strain detection unit, a displacement detection unit, and a photographic unit; A control and data acquisition mechanism is electrically connected to the detection component, and the control and data acquisition mechanism is located on one side of the frame (1).

2. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 1 is characterized in that: An impact head bracket (7) is fixedly connected to the bottom of the frame (1), a reinforced concrete slab is fixedly connected to the bottom of the impact head bracket (7), an impact head is vertically slidably connected to the impact head bracket (7), a spoke-type force sensor is fixedly connected to the top of the impact head, and the bottom of the impact head is arranged in contact with the center of the surface of the reinforced concrete slab; A pipeline for the sliding of the weight (3) is provided in the middle of the impact head bracket (7), the impact head is located at the bottom end of the pipeline, and the weight (3) hits the top of the impact head through the pipeline; The spoke-type force sensor is electrically connected to the control and data acquisition mechanism.

3. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 2 is characterized in that: The lifting and releasing mechanism comprises: An automatic wire retracting and releasing pulley assembly (2) is arranged on the top of the frame (1), a steel wire rope (9) is wound around the automatic wire retracting and releasing pulley assembly (2), one end of the steel wire rope (9) is fixedly connected to the weight (3), and the other end of the steel wire rope (9) is transmission-connected to a driving unit.

4. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 3 is characterized in that: The driving part comprises a winch (13), one end of the winch (13) is fixedly connected to one end of the steel wire rope (9), and the winch (13) is electrically connected to the control and data acquisition mechanism.

5. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 2 is characterized in that: The top axis of the pipeline is connected to the bottom end of a transparent pipe (4), and the transparent pipe (4) is vertically slidably connected to the weight (3).

6. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 5 is characterized in that: The inner diameter of the transparent pipe (4) matches the outer diameter of the weight (3).

7. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 4 is characterized in that: The acoustic detection mechanism comprises a plurality of acoustic emission sensors (11), and the acoustic emission sensors (11) are used to receive and record acoustic emission signals; the plurality of acoustic emission sensors (11) are fixedly connected to the surface of the reinforced concrete slab, and the acoustic emission sensors (11) are electrically connected to the control and data acquisition mechanism; The strain detection unit includes a plurality of strain gauges, which are fixed to the reinforced concrete slab and are used to detect and record strain data, time data, resistance change of the strain gauge and voltage signal data when an impact load acts on the reinforced concrete slab; The displacement detection unit comprises a displacement meter (12), the fixed end of the displacement meter (12) is fixedly connected to the frame (1), the movable end of the displacement meter (12) is in contact with the bottom center of the reinforced concrete slab, and the displacement meter (12) is used to detect the deformation amount of the reinforced concrete slab under impact load; The photographic unit comprises a high-speed camera (8), which is arranged on one side of the frame (1) and is used to photograph changes in the reinforced concrete slab surface and the speed and impact contact time of the heavy object (3) when it impacts.

8. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 7 is characterized in that: The control and data acquisition mechanism includes: A PLC programmable controller (5), wherein the PLC programmable controller (5) is electrically connected to the acoustic emission sensor (11), the hoist (13) and the spoke-type force sensor, the PLC programmable controller (5) is used to control the rotation of the hoist (13), and the PLC programmable controller (5) is used to receive feedback data from the acoustic emission sensor (11) and the spoke-type force sensor.

9. The acoustic emission detection experimental device for reinforced concrete slabs under impact load according to claim 8, characterized in that: The PLC programmable controller (5) is fixed on the ground via a PLC bracket (6).

10. An acoustic emission detection experimental method for reinforced concrete slabs under impact load, using the acoustic emission detection experimental device for reinforced concrete slabs under impact load according to any one of claims 1 to 9, characterized in that: The steps include: Arranging the acoustic detection mechanism on a reinforced concrete slab; Installing a reinforced concrete slab at the bottom of the frame (1); The control and data acquisition mechanism controls the lifting and releasing mechanism to lift the weight (3) to a specified height, and then releases the weight (3). The weight (3) impacts the middle of the reinforced concrete slab, and the control and data acquisition mechanism collects feedback data from the acoustic detection mechanism, the strain detection unit, the displacement detection unit and the photographic unit.

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