A specimen damage real-time detection device and a method thereof

Abstract

The application discloses a kind of specimen damage real-time detection device and method thereof, the detection device includes square hollow test cavity, test cavity is provided with the opening for true triaxial hopkinson bar to pass through, the inside of test cavity is provided with the accommodating space of placing test body;The accommodating space is also provided with square acoustic wave transmitter and square acoustic wave receiver, and a plurality of shock absorbers for fixing acoustic wave transmitter and acoustic wave receiver;Test body is clamped by acoustic wave transmitter and acoustic wave receiver, the opposite surface of acoustic wave transmitter and acoustic wave receiver away from test body is all abutted on the inner surface of test cavity, one end of shock absorber is detachably arranged on the surface of acoustic wave transmitter and / or acoustic wave receiver perpendicular to clamping direction, the other end of shock absorber is detachably arranged on the inner surface of test cavity.The application does not need to unload test body, avoids further damage in rock interior, and can more accurately measure the real damage condition in test body interior.

Description

Technical Field

[0001] This invention relates to the field of acoustic wave detection, and more specifically to a real-time sample damage detection device and method. Background Technology

[0002] Currently, the true triaxial Hopkinson bar test is generally used to study the damage and failure mechanisms and material properties of materials such as rocks. The true triaxial Hopkinson bar test effectively simulates the situation where rocks are subjected to impact loads under confining pressure. First, confining pressure is applied to the test body through a Hopkinson bar, and then an impact bar is used to impact the incident bar, forming an impact load. The impact load generates stress waves that are transmitted to the interior of the test body, causing damage inside the test body. Different rocks have different impact load capacities, and the damage inside the test body cannot be directly obtained. Generally, an acoustic instrument is needed to detect the test body using acoustic waves, and only through measurement can the damage inside the test body be determined.

[0003] True triaxial Hopkinson bar testing can effectively simulate the damage to materials such as rocks under confining pressure and the influence of stress waves. However, to accurately measure the internal damage of the rock, it is necessary to unload the rock and then use an acoustic wave meter to measure the wave velocity within the rock. Because unloading causes an unloading effect, the internal damage state of the rock differs from that before unloading. Therefore, acoustic wave testing after unloading cannot accurately reflect the internal damage state of the rock under impact loading. Furthermore, under cyclic loading, we cannot accurately determine the damage condition of the rock. In addition, to accurately measure the internal damage of the rock using an acoustic wave meter, it is necessary to unload the rock and then measure the wave velocity within it.

[0004] Therefore, there is an urgent need to propose a new detection device and method to solve the above problems. Summary of the Invention

[0005] This invention provides a real-time sample damage detection device and method. This detection device solves the problem in the prior art that the test body needs to be unloaded and then the wave velocity inside the test body needs to be measured by an acoustic instrument in order to accurately measure the damage inside the test body.

[0006] The present invention provides a real-time test sample damage detection device, the detection device comprising a square hollow test cavity, the test cavity having an opening for a true triaxial Hopkinson bar to pass through, and the interior of the test cavity having a space for placing the test sample;

[0007] The accommodating space is also equipped with a square sound wave transmitter and a square sound wave receiver, as well as multiple shock absorbers for fixing the sound wave transmitter and the sound wave receiver.

[0008] The test body is held by the sound wave transmitter and the sound wave receiver. The opposite surfaces of the sound wave transmitter and the sound wave receiver away from the test body abut against the inner surface of the test chamber. One end of the shock absorber is detachably disposed on the surface of the sound wave transmitter and / or the sound wave receiver perpendicular to the clamping direction, and the other end of the shock absorber is detachably disposed on the inner surface of the test chamber.

[0009] The sound wave transmitter and the sound source signal generator are electrically connected via a sound wave transmitting line, and the sound wave receiver and the microcomputer are electrically connected via a sound wave receiving line.

[0010] Furthermore, the true triaxial Hopkinson bar is mounted on a horizontal cross support platform, which includes an X-positive support platform, an X-negative support platform, a Y-positive support platform, a Y-negative support platform, and a central support platform. The test chamber is placed above the central support platform.

[0011] Furthermore, the test chamber includes multiple detachable sub-test chambers.

[0012] Furthermore, the material of the shock absorber is rubber.

[0013] Furthermore, the shock absorber includes a shock absorber body and a shock absorber base that is fixedly connected to the shock absorber body by vulcanization. The shock absorber base has multiple circular holes for fastening screws to pass through, and the test chamber has threaded grooves corresponding to the circular holes at the corresponding positions.

[0014] Furthermore, the number of shock absorbers on the sound wave transmitter or receiver is multiple pairs, and the axis of each pair of shock absorbers is on a straight line.

[0015] Furthermore, the surfaces of both the sound wave transmitter and the sound wave receiver are coated with petroleum jelly.

[0016] Furthermore, the sound source signal generator and the microcomputer are integrated in the ultrasonic signal generation and processing center, which is connected to an external computer.

[0017] The present invention also provides a method for real-time detection of sample damage, comprising the following steps:

[0018] S1. Turn on the ultrasonic signal generation and processing center to generate an ultrasonic signal. Then, push the Y-axis Hopkinson rod close to the sound wave transmitter and receiver through the hydraulic cylinder so that the sound wave signal can pass through the test body and be received by the sound wave receiver. When the ultrasonic signal generation and processing center can read the wave velocity, record and save the first ultrasonic wave velocity without applying static confining pressure and impact load, and then turn off the sound source signal generator.

[0019] S2. First, open the X-direction high-pressure oil pipe and fill the hydraulic cylinder with oil. By controlling the hydraulic cylinder, push the X-direction Hopkinson rod forward into the test chamber and then act on the test body so that the test body is accurately subjected to static confining pressure. Following the steps of the X-direction above, apply static confining pressure to the Hopkinson rods in the other five directions as well.

[0020] S3. While maintaining static confining pressure on the Hopkinson rods in six directions, the ultrasonic signal generation and processing center is activated again to generate ultrasonic signals. These signals are emitted through the sound wave transmitter, pass through the test body, and are received by the sound wave receiver. The ultrasonic signal generation and processing center then performs relevant processing, records, and saves the second ultrasonic wave velocity after the static confining pressure is applied. By comparing it with the first ultrasonic wave velocity, if the difference is within 5%, proceed to the next step. If the difference is more than 5%, release the static confining pressure, check whether the sound wave transmitter and receiver are aligned, and whether the ultrasonic signal generation and processing center is operating normally. If the check is correct, repeat S1 to S3 until the difference between the second and first ultrasonic wave velocities is within 5%, and then turn off the sound source signal generator.

[0021] S4. Continue to keep the static confining pressure unchanged, apply impact loads to the Hopkinson rods in six directions simultaneously, turn on the ultrasonic signal generation and processing center to generate ultrasonic signals, emit them through the sound wave transmitter, pass through the test body, and be received by the sound wave receiver. Record and save the third ultrasonic wave velocity of the cyclic impact load test, and then turn off the sound source signal generator.

[0022] S5. Shut down the hydraulic system and slowly release the pressure in the cylinder. After all the static confining pressure applied to the Hopkinson rod in six directions is released, turn on the ultrasonic signal generation and processing center to generate ultrasonic signals, record and save the fourth ultrasonic wave velocity after the static confining pressure is released, and then turn off the sound source signal generator.

[0023] S6. By comparing the magnitudes of the third and fourth ultrasonic wave velocities, if the third ultrasonic wave velocity is greater than the fourth ultrasonic wave velocity, it indicates that an unloading effect occurs inside the test body.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. The real-time sample damage detection device of the present invention uses multiple shock absorbers to directly abut the sound wave transmitter and the sound wave receiver at both ends of the test body, without unloading the test body, thus avoiding further damage inside the rock and accurately measuring the actual damage inside the test body.

[0026] 2. The test chamber of the real-time sample damage detection device of the present invention is composed of multiple small chambers spliced ​​together by bolts, which facilitates the assembly of the test body, the sound wave transmitter, the sound wave receiver and the shock absorber;

[0027] 3. The real-time sample damage detection method of the present invention proves the reliability of the detection device. In addition, it can accurately measure the actual damage inside the test body without unloading the test body, thus avoiding further damage inside the rock. Attached Figure Description

[0028] Figure 1 This is a perspective view of the real-time sample damage detection device of the present invention;

[0029] Figure 2 This is a Y-axis view of the real-time sample damage detection device of the present invention;

[0030] Figure 3 This is an X-axis view of the real-time sample damage detection device of the present invention;

[0031] Figure 4 This is a perspective view of the real-time sample damage detection device of the present invention detached from the test chamber;

[0032] Figure 5 This is a perspective view of a single shock absorber in the real-time sample damage detection device of the present invention;

[0033] Figure 6 This is a perspective view of the test chamber of the real-time sample damage detection device of the present invention;

[0034] Figure 7 This is a perspective view of the combination of the real-time sample damage detection device and the Hopkinson bar of the present invention.

[0035] Figure 8 This is a comparison diagram of the wave velocity before the applied stress wave using the detection device of the present invention and a conventional acoustic wave meter;

[0036] Figure 9 This is a comparison diagram of the wave velocity of the detection device of the present invention and a conventional acoustic wave instrument after stress wave application;

[0037] Figure 10 This is a comparison chart of the integrity coefficients of the detection device of the present invention and a conventional acoustic instrument;

[0038] Reference numerals in the attached diagram: 1. Horizontal cross support platform; 11. X-direction positive support platform; 12. X-direction negative support platform; 13. Y-direction positive support platform; 14. Y-direction negative support platform; 15. Central support platform; 2. Test body; 31. Acoustic wave transmitter; 32. Acoustic wave transmitting line; 41. Acoustic wave receiver; 42. Acoustic wave receiving line; 5. Vibration damper; 51. Vibration damper body; 52. Vibration damper base; 521. Circular hole; 6. Test chamber; 61. First sub-test chamber; 62. Second sub-test chamber; 63. Third sub-test chamber; 64. Fourth sub-test chamber; 7. Ultrasonic signal generation and processing center. Detailed Implementation

[0039] The following is in conjunction with the appendix Figures 1-10 The present invention will be further described in detail with reference to specific embodiments.

[0040] like Figures 1-2 As shown, the present invention discloses a real-time sample damage detection device, which includes a square hollow test cavity 6, an opening on the test cavity 6 for a true triaxial Hopkinson bar to pass through, and an accommodating space for placing the test body 2 inside the test cavity 6.

[0041] The space also contains a square sound wave transmitter 31 and a square sound wave receiver 41, as well as four shock absorbers 5 for fixing the sound wave transmitter 31 and the sound wave receiver 41.

[0042] The test body 2 is clamped by a sound wave transmitter 31 and a sound wave receiver 41. The opposing surfaces of the sound wave transmitter 31 and the sound wave receiver 41 away from the test body 2 abut against the inner surface of the test chamber 6. One end of the shock absorber 5 is detachably disposed on the surface of the sound wave transmitter 31 and / or the sound wave receiver 41 perpendicular to the clamping direction, and the other end of the shock absorber 5 is detachably disposed on the inner surface of the test chamber 6.

[0043] The sound wave transmitter 31 is electrically connected to the sound source signal generator through the sound wave transmitting line 32, and the sound wave receiver 41 is electrically connected to the microcomputer through the sound wave receiving line 42.

[0044] The real-time sample damage detection device of the present invention uses four shock absorbers to directly connect the sound wave transmitter and the sound wave receiver to both ends of the test body. This eliminates the need to unload the test body and avoids further damage to the rock interior, thus accurately measuring the actual damage inside the test body.

[0045] like Figure 7As shown, in this embodiment, the true triaxial Hopkinson bar is set on the horizontal cross support platform 1. The horizontal cross support platform 1 includes an X positive support platform 11, an X negative support platform 12, a Y positive support platform 13, a Y negative support platform 14 and a central support platform 15. The test chamber 6 is placed above the central support platform 15.

[0046] like Figure 7 As shown, in this embodiment, the test chamber 6 includes a first sub-test chamber 61, a second sub-test chamber 62, a third sub-test chamber 6, and a fourth sub-test chamber 6, which are detachably connected to each other by bolts. Of course, the number of sub-test chambers can also be other convenient installation quantities. The test chamber of the real-time sample damage detection device of the present invention is composed of multiple small chambers spliced ​​together by bolts, which facilitates the assembly of the test body, the sound wave transmitter, the sound wave receiver, and the shock absorber.

[0047] In this embodiment, the shock absorber 5 is made of rubber, which not only serves a fixing function, but also reduces vibration for the sound wave transmitter and receiver.

[0048] like Figure 4 As shown, in this embodiment, the number of shock absorbers 5 on the sound wave transmitter 31 or the sound wave receiver 41 is one pair, that is, one on each side, located at the center of their sides. However, two or more pairs can also be used. The axes of each pair of shock absorbers 5 are on a straight line. The alignment of the axes ensures the final shock absorption effect.

[0049] In this embodiment, as Figure 5 As shown, the shock absorber 5 includes a shock absorber body 51 and a shock absorber base 52 fixedly connected to the shock absorber body 51 by vulcanization. The shock absorber base 52 has multiple circular holes 521 for fastening screws to pass through. Corresponding threaded grooves are provided in the test chamber 6 at corresponding positions. Both ends of the shock absorber body 51 utilize shock absorber bases 52, facilitating the installation of the shock absorber.

[0050] In this embodiment, the surfaces of both the sound wave transmitter 31 and the sound wave receiver 41 are coated with petroleum jelly to improve the transmission of ultrasonic signals.

[0051] In this embodiment, as Figure 1 As shown, the sound source signal generator and microcomputer are integrated inside the ultrasonic signal generation and processing center 7, which is mounted on a fixed bracket (not shown in the figure). This ultrasonic signal generation and processing center 7 is connected to an external computer wirelessly or via wired connection. The microcomputer generates wave velocities, and the external computer integrates the wave velocities from multiple tests to generate a wave velocity diagram, as shown below. Figures 8-10 As shown.

[0052] In this embodiment, as Figure 1 and 6 As shown, the first sub-test chamber 61 is located in the first quadrant of the horizontal plane containing the X and Y axes, the second sub-test chamber 62 is located in the second quadrant, the third sub-test chamber 63 is located in the third quadrant, and the fourth sub-test chamber is located in the fourth quadrant. They are assembled into a large cube using bolts. The openings along the X and Z axes are square, allowing passage of the Hopkinson square rod. The opening along the Y axis is T-shaped, allowing passage of both the Hopkinson square rod and the sound wave receiving line 42 and the sound wave emitting line 32.

[0053] Four shock absorbers 5 are connected to the two ends of the sound wave transmitter 31 and the sound wave receiver 41 respectively using screws. Each sub-test chamber has threaded holes on its inner surface for connecting the shock absorbers 5. The first sub-test chamber 61 and the second sub-test chamber 62 are first fixed with surface bolts. Then, the shock absorbers 5 and the sound wave receiver 41 are fixedly connected as a whole to the corresponding positions on the inner surfaces of the first sub-test chamber 61 and the second sub-test chamber 62. The first sub-test chamber 61, the second sub-test chamber 62, the shock absorbers 5, and the sound wave receiver 41 constitute the first chamber. Then, the third sub-test chamber 63 and the fourth sub-test chamber 64 are connected in a similar way. The third sub-test chamber 63, the fourth sub-test chamber 64, the shock absorbers 5, and the sound wave transmitter 31 constitute the second chamber. Next, the sound wave transmitter 31 is connected to the sound source signal generator through a sound wave transmitting line, and the sound wave receiver 41 is connected to the microcomputer through a sound wave receiving line. Check if the testing device is operating normally. If it is not operating normally, it needs to be adjusted and repaired.

[0054] After the test is running normally, first place the test body 2 on the Z-negative axis Hopkinson rod, and adjust the Z-negative axis Hopkinson rod to the height inside the test chamber. Align the first and second cavities with the test body 2, so that the test body 2 is located in the center position inside the test chamber 6. The surfaces of the sound wave transmitter 31 and the sound wave receiver 41 that contact the test body 2 are coated with Vaseline. At the same time, the sound wave emitting line 32 and the sound wave receiving line 42 also pass out from the Y-axis. Finally, connect the first and second cavities with bolts. After the test chamber 6 and its internal devices are installed, align the Hopkinson rods in other directions with the corresponding openings of the test chamber 6, so that the Hopkinson rods on the Y-axis and Z-axis abut against the four surfaces of the test body, and the Hopkinson rods in the positive and negative X-axis abut against the sound wave receiver 41 and the sound wave transmitter 31, respectively.

[0055] The present invention also provides a detection method for a real-time sample damage detection device, comprising the following steps:

[0056] S1. Turn on the ultrasonic signal generation and processing center to generate an ultrasonic signal. Then, push the Y-axis Hopkinson rod close to the sound wave transmitter 31 and the sound wave receiver 41 through the hydraulic cylinder so that the sound wave signal can pass through the test body 2 and be received by the sound wave receiver 41. When the ultrasonic signal generation and processing center can read the wave velocity, record and save the first ultrasonic wave velocity without applying static confining pressure and impact load, and then turn off the sound source signal generator.

[0057] S2. First, open the X-direction high-pressure oil pipe and fill the hydraulic cylinder with oil. By controlling the hydraulic cylinder, push the X-direction Hopkinson rod forward into the test chamber and then act on the test body so that the test body is accurately subjected to static confining pressure. Following the steps of the X-direction above, apply static confining pressure to the Hopkinson rods in the other five directions as well.

[0058] S3. While maintaining static confining pressure on the Hopkinson rods in six directions, the ultrasonic signal generation and processing center is activated again to generate ultrasonic signals. These signals are emitted through the sound wave transmitter 31, pass through the test body 2, and are received by the sound wave receiver 41. The ultrasonic signal generation and processing center then performs relevant processing, records and saves the second ultrasonic wave velocity after the static confining pressure is applied. By comparing it with the first ultrasonic wave velocity, if the difference is within 5%, the next step is continued. If the difference is more than 5%, the static confining pressure is released, and the alignment of the sound wave transmitter 32 and the sound wave receiver 42 is checked, as well as the normal operation of the ultrasonic signal generation and processing center. If the checks are correct, S1 to S3 are repeated until the difference between the second and first ultrasonic wave velocities is within 5%, and then the sound source signal generator is turned off.

[0059] S4. Continue to keep the static confining pressure unchanged, apply impact loads to the Hopkinson rods in six directions simultaneously, turn on the ultrasonic signal generation and processing center to generate ultrasonic signals, emit them through the sound wave transmitter 31, pass through the test body 2, and be received by the sound wave receiver 41, record and save the third ultrasonic wave velocity of the cyclic impact load test, and then turn off the sound source signal generator.

[0060] S5. Shut down the hydraulic system and slowly release the pressure in the cylinder. After all the static confining pressure applied to the Hopkinson rod in six directions is released, turn on the ultrasonic signal generation and processing center to generate ultrasonic signals, record and save the fourth ultrasonic wave velocity after the static confining pressure is released, and then turn off the sound source signal generator.

[0061] S6. By comparing the magnitudes of the third and fourth ultrasonic wave velocities, if the third ultrasonic wave velocity is greater than the fourth ultrasonic wave velocity, it indicates that an unloading effect occurs inside the test body 2.

[0062] The real-time sample damage detection method of the present invention proves the reliability of the detection device, and that an unloading effect does exist after the static confining pressure is removed.

[0063] Following steps S1 to S6 above, the test object 2 in this embodiment is granite, and the test results according to the detection method of the present invention are shown in Table 1 below.

[0064] Table 1. Granite Test Results

[0065] Wave speed (m / s) 5261 5309 4631 4357

[0066] As shown in Table 1 above, the damage to granite can be evaluated by ultrasonic wave velocity. The higher the wave velocity, the better the rock damage; the lower the wave velocity, the worse the rock damage.

[0067] As shown in Table 1, the difference between the first and second ultrasonic wave velocities is small, indicating that the detection device of this invention provides reliable results under static confining pressure. Comparing the second and third ultrasonic wave velocities, it is evident that the wave velocity of the granite decreases after applying an impact load, indicating internal damage. Comparing the third and fourth ultrasonic wave velocities, the difference is 5.98%, which is greater than 5%, showing a slight decrease in wave velocity after the confining pressure is released. This indicates that the granite experiences an unloading effect after the confining pressure is released, leading to some internal damage. Therefore, compared to existing detection methods, the detection method of this embodiment can verify the reliability of the detection device. Furthermore, it eliminates the need to unload the test object, avoiding further damage to the rock, and accurately measures the actual internal damage of the test object.

[0068] In this embodiment, the detection device of the present invention was compared with a conventional acoustic instrument under the same conditions.

[0069] The microcomputer processes the data to obtain a single data point. Each time an impact load of 0.3 MPa is applied, different data points for the test specimen can be obtained. Based on the data of the test specimen under different conditions, the real-time damage status of the specimen can be obtained.

[0070] The data processing method in the microcomputer of this invention is based on the existing integrity coefficient K. i The formula is as follows:

[0071]

[0072] Where K i Let be the integrity coefficient after the i-th impact;

[0073] V0 is the velocity of the sound wave received by the microcomputer before the first impact load.

[0074] Vi Let be the velocity of the sound wave received by the microcomputer after the i-th impact load.

[0075] First, test body 2 is installed inside the detection device of this invention. The Hopkinson rods along the X and Y axes are then installed within the device using hydraulic cylinders, and a confining pressure of 1 kN is applied. Ordinary acoustic transducers are installed at both ends of the Z-axis of test body 2, while the acoustic transmitter 31 and receiver 41 of the detection device of this invention are installed along the X-axis. Both acoustic transducers are turned on, and data is recorded. After the entire device has stabilized for 10 seconds, a stress wave is applied to the test body through the Hopkinson rods along the X and Y axes. After the device has stabilized for another 10 seconds, the data from both acoustic transducers are recorded again. Finally, the confining pressure is removed, another test body 2 is reinstalled, and the above steps are repeated.

[0076] In this embodiment, a total of five experiments were conducted, and the data obtained are shown below.

[0077] Table 2 Comparison of wave velocities between the detection device of the present invention and a conventional acoustic instrument under loading conditions.

[0078]

[0079] Table 2 above records the wave velocity comparison and integrity coefficient of the five test objects before and after the stress wave is applied, and gives the difference between the detection device of the present invention and the ordinary acoustic instrument. Difference 1 is the difference in wave velocity before the stress wave is applied, difference 2 is the difference in wave velocity after the stress wave is applied, and difference 3 is the difference in integrity coefficient between the two acoustic instruments.

[0080] As can be seen from the data in the table, the difference between the detection device of the present invention and the ordinary acoustic instrument is within 5%. This shows that the data measured by the detection device of the present invention and the ordinary acoustic instrument in the same test body are basically consistent. Therefore, the data obtained by the detection device of the present invention has a high degree of reliability.

[0081] Comparison test of the detection device of the present invention with the wave velocity of a conventional acoustic instrument measured after unloading.

[0082] First, test body 2 is subjected to acoustic wave testing using a conventional acoustic instrument, and the data is recorded when unloaded. Then, test body 2 is installed in the detection device of this invention. The Hopkinson rods along the X, Y, and Z axes are installed in the device using hydraulic cylinders, and a confining pressure of 1 kN is applied, while simultaneously recording the data when unloaded. After the entire device has stabilized for 10 seconds, a stress wave is applied to the test body through the Hopkinson rods along the X, Y, and Z axes. After the device stabilizes, the wave velocity and integrity coefficient after applying the stress wave are recorded using the detection device of this invention. Finally, the confining pressure is removed, and the wave velocity of test body 2 is measured again using a conventional acoustic instrument. This data is recorded, and the integrity coefficient is calculated. Then, another test body 2 is installed, and the above steps are repeated.

[0083] A total of five experiments were conducted, and the data obtained are shown in Table 3 below:

[0084] Table 3 Comparison of wave velocity between the detection device of the present invention and a conventional acoustic instrument

[0085]

[0086] From Tables 2-3 above and Figures 8-10 As shown, before the stress wave was applied, the wave velocities measured by this device and the ordinary sonic logging instrument were basically the same. However, after the stress wave was applied using the triaxial Hopkinson bar, the wave velocity measured in situ by this device differed from the wave velocity measured by the ordinary sonic logging instrument after unloading by approximately 10%, while the difference in the integrity coefficient of the test body was about 20%. This indicates that there is a significant unloading effect after the test body is unloaded in the triaxial Hopkinson test, resulting in secondary damage to the test body after unloading. The ordinary sonic logging instrument cannot obtain the in-situ rock damage information.

[0087] The above-described invention merely illustrates implementation methods of the present invention and should not be construed as limiting the scope of the invention patent, nor as imposing any form of limitation on the structure of the embodiments of the present invention. It should be noted that those skilled in the art can make various changes and improvements without departing from the concept of the embodiments of the present invention, and these all fall within the protection scope of the embodiments of the present invention.

Claims

1. A real-time test sample damage detection device, the detection device comprising a square hollow test cavity (6), the test cavity (6) having an opening for a true triaxial Hopkinson bar to pass through, and the interior of the test cavity (6) having a space for placing a test body (2); characterized in that The accommodating space is also provided with a square sound wave transmitter (31) and a square sound wave receiver (41), as well as a plurality of shock absorbers (5) for fixing the sound wave transmitter (31) and the sound wave receiver (41). The test body (2) is held by the sound wave transmitter (31) and the sound wave receiver (41). The opposing surfaces of the sound wave transmitter (31) and the sound wave receiver (41) away from the test body (2) abut against the inner surface of the test chamber (6). One end of the shock absorber (5) is detachably disposed on the surface of the sound wave transmitter (31) and / or the sound wave receiver (41) perpendicular to the holding direction. The other end of the shock absorber (5) is detachably disposed on the inner surface of the test chamber (6). The sound wave transmitter (31) is electrically connected to the sound source signal generator through the sound wave transmitting line (32), and the sound wave receiver (41) is electrically connected to the microcomputer through the sound wave receiving line (42). The test chamber (6) includes multiple detachable sub-test chambers; The material of the shock absorber (5) is rubber; The shock absorber (5) includes a shock absorber body (51) and a shock absorber base (52) which is fixedly connected to the shock absorber body (51) by vulcanization. The shock absorber base (52) has multiple round holes (521) for fastening screws to pass through. The test chamber (6) has a threaded groove corresponding to the round holes (521) at the corresponding position.

2. The device for real-time detection of sample damage according to claim 1, characterized in that: The true triaxial Hopkinson bar is set on a horizontal cross support platform (1). The horizontal cross support platform (1) includes an X positive support platform (11), an X negative support platform (12), a Y positive support platform (13), a Y negative support platform (14), and a central support platform (15). The test chamber (6) is placed above the central support platform (15).

3. The device for real-time detection of sample damage according to claim 1, characterized in that: The number of shock absorbers (5) on the sound wave transmitter (31) or sound wave receiver (41) is multiple pairs, and the axis of each pair of shock absorbers (5) is on a straight line.

4. The real-time sample damage detection device according to claim 1, characterized in that: The surfaces of the sound wave transmitter (31) and the sound wave receiver (41) are both coated with petroleum jelly.

5. The real-time sample damage detection device according to claim 1, characterized in that: The sound source signal generator and microcomputer are integrated in the ultrasonic signal generation and processing center (7), which is connected to an external computer.

6. The detection method using the real-time sample damage detection device as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Turn on the ultrasonic signal generation and processing center to generate an ultrasonic signal. Then, push the Y-axis Hopkinson rod close to the sound wave transmitter (31) and the sound wave receiver (41) through the hydraulic cylinder so that the sound wave signal can pass through the test body (2) and be received by the sound wave receiver (41). When the ultrasonic signal generation and processing center can read the wave velocity, record and save the first ultrasonic wave velocity without applying static confining pressure and impact load, and then turn off the sound source signal generator. S2. First, open the X-direction high-pressure oil pipe and fill the hydraulic cylinder with oil. By controlling the hydraulic cylinder, push the X-direction Hopkinson rod forward into the test chamber and then act on the test body so that the test body is accurately subjected to static confining pressure. Following the steps of the X-direction above, apply static confining pressure to the Hopkinson rods in the other five directions as well. S3. While maintaining static confining pressure on the Hopkinson rods in six directions, the ultrasonic signal generation and processing center is turned on again to generate ultrasonic signals. These signals are emitted through the sound wave transmitter (31), pass through the test body (2), and are received by the sound wave receiver (41). The ultrasonic signal generation and processing center then performs relevant processing, records and saves the second ultrasonic wave velocity after the static confining pressure is applied. By comparing it with the first ultrasonic wave velocity, if the difference is within 5%, the next step is continued. If the difference is more than 5%, the static confining pressure is released, and the alignment of the sound wave transmitter (32) and the sound wave receiver (42) is checked, as well as the normal operation of the ultrasonic signal generation and processing center. If the check is correct, S1~S3 are repeated until the difference between the second ultrasonic wave velocity and the first ultrasonic wave velocity is within 5%, and then the sound source signal generator is turned off. S4. Continue to keep the static confining pressure unchanged, apply impact loads to the Hopkinson rods in six directions simultaneously, turn on the ultrasonic signal generation and processing center, generate ultrasonic signals, emit them through the sound wave transmitter (31), pass through the test body (2), and be received by the sound wave receiver (41), record and save the third ultrasonic wave velocity of the cyclic impact load test, and then turn off the sound source signal generator. S5. Shut down the hydraulic system and slowly release the pressure in the cylinder. After all the static confining pressure applied to the Hopkinson rod in six directions is released, turn on the ultrasonic signal generation and processing center to generate ultrasonic signals, record and save the fourth ultrasonic wave velocity after the static confining pressure is released, and then turn off the sound source signal generator. S6. By comparing the magnitudes of the third and fourth ultrasonic wave velocities, when the third ultrasonic wave velocity is greater than the fourth ultrasonic wave velocity, it indicates that an unloading effect occurs inside the test body (2).

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