A pressure testing device and test method for aggregate crushing value test

Abstract

The present invention provides a pressure testing device and a testing method for aggregate crushing value testing, which belong to the field of aggregate detection technology. The pressure testing device includes an equipment platform, a pad and a press, three support blocks are fixedly installed on the top of the pad, and a transfer mechanism is provided on the equipment platform, and the transfer mechanism includes a lifting component and a moving component, and the lifting component is used to adjust the height of the moving component. The test method includes: T1: screening the aggregate, removing particles that do not meet the particle size requirements, and weighing aggregate of a specified mass as a test sample; T2: placing the circular mold in the test mold in the circular groove on the chassis, and then pouring the weighed aggregate into the circular groove. The pressure testing device for aggregate crushing value testing provided by the present invention has the advantages of being able to automatically transfer the test mold to a predetermined position in the press, accurately positioning the test mold, being able to automatically impact the aggregate, and being reliable to use.

Description

Technical Field

[0001] The present invention relates to the technical field of aggregate detection, and in particular to a pressure testing device and a testing method for aggregate crushing value testing. Background Art

[0002] The aggregate crushing value test is an important test method for evaluating the mechanical properties of aggregates. It is mainly used to measure the ability of aggregates to resist crushing under gradually increasing loads. It is a key indicator for aggregate quality testing in engineering fields such as roads and construction. The basic process of this test is: the prepared aggregate sample is placed in a test mold of specific specifications, and a specified pressure is applied to the pressure head of the test mold through a press to make the aggregate withstand the compressive load. The crushing value is then calculated based on the change in the aggregate particle grading after crushing to determine the strength and applicability of the aggregate. Before applying pressure, the position of the test mold needs to be adjusted so that the axis of the test mold coincides with the axis of the press head as much as possible. This will make the force on the aggregate more uniform and improve the accuracy of the test results.

[0003] However, existing testing procedures rely on manual placement of the test mold under the press head. After the test mold is placed, the tester must observe the relative position of the test mold and the press head closely after the press head has descended a certain distance. If the deviation is too large, the test mold position must be manually adjusted. This operation method can easily cause mechanical injury to the tester in the event of equipment failure or operational error, posing a significant safety risk. Furthermore, manual observation and adjustment of the test mold position has limited accuracy, making it difficult to ensure accurate alignment of the test mold's axis with the press head's axis. This can lead to uneven force on the aggregate, affecting the accuracy and reliability of the test results.

[0004] Therefore, it is necessary to provide a pressure testing device and test method for aggregate crushing value testing to solve the above technical problems. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a pressure testing device and test method for testing aggregate crushing value, which can automatically transfer the test mold to a predetermined position in a press, accurately position the test mold, automatically impact the aggregate, and use reliable aggregate crushing value.

[0006] In order to solve the above technical problems, the present invention provides a pressure testing device for aggregate crushing value test, including an equipment platform, a pad and a press. The pad is fixedly installed on the top of the equipment platform, and the press is fixedly installed on the top of the pad. Three support blocks are fixedly installed on the top of the pad. A transfer mechanism is provided on the equipment platform, and the transfer mechanism includes a lifting assembly and a moving assembly. The lifting assembly is used to adjust the height of the moving assembly. A positioning placing table is installed on the moving assembly, and the moving assembly is used to move the positioning placing table to above the three support blocks. A positioning groove is provided on the top of the positioning placing table, and the positioning groove is used to place a test mold for the aggregate crushing value test.

[0007] Preferably, a square opening is provided on the pad, a movable carrier is slidably installed in the square opening, the movable assembly is installed on the movable carrier, a screw is rotatably installed in the square opening, the screw passes through the movable carrier and is threadedly connected to the movable carrier, a first motor is fixedly installed on one side of the equipment platform, one end of the screw extends to the outside of the equipment platform and is fixedly connected to the output end of the first motor.

[0008] Preferably, the lifting assembly includes a plurality of fixed columns, a supporting circular plate, an I-beam and a first hydraulic cylinder, the plurality of fixed columns are fixedly mounted on the bottom of the movable carrier plate, the supporting circular plate is fixedly mounted on the bottom ends of the plurality of fixed columns, the I-beam is slidably sleeved on the plurality of fixed columns, the top of the I-beam extends to above the equipment platform, the first hydraulic cylinder is fixedly mounted on the top of the supporting circular plate, and the output end of the first hydraulic cylinder is fixedly connected to the bottom of the I-beam.

[0009] Preferably, the moving assembly includes a mounting seat, a transfer plate, a rack, a second motor and a gear, the mounting seat is fixedly mounted on the top of the I-beam, the transfer plate passes through and is slidably mounted on the mounting seat, the rack is fixedly mounted on the top of the transfer plate, the second motor is fixedly mounted on the mounting seat, the gear is fixedly sleeved on the output end of the second motor, and the gear is meshed with the rack, the transfer plate is close to the press and is integrally formed with two front end support bars, two limiting round rods are fixedly mounted on the top of the two front end support bars, and the positioning holding platform is slidably sleeved on the four limiting round rods.

[0010] Furthermore, two positioning blocks are fixedly installed on the top of the pad.

[0011] Furthermore, the movable carrier and the positioning and placing table are also provided with an impact mechanism for impacting the test mold for the aggregate crushing value test. The impact mechanism includes a power assembly and two pushing assemblies. The two pushing assemblies are both installed on the positioning and placing table and are respectively located on both sides of the transfer plate. The power assembly is installed on the movable carrier.

[0012] Preferably, the power assembly includes a rotating shaft, two cams and a third motor, wherein the rotating shaft is rotatably mounted on the top of the movable carrier, the two cams are fixedly sleeved on the rotating shaft, and the phase difference between the two cams is 180°, the third motor is fixedly mounted on the top of the movable carrier, and the output end of the third motor is fixedly connected to one end of the corresponding rotating shaft;

[0013] Any one of the pushing assemblies includes two push rods, a resistance block and two first springs. A smooth hole connected to the positioning groove is provided at the bottom of the positioning platform. The two push rods are slidably installed in the corresponding smooth holes. The resistance block is fixedly installed at the bottom ends of the two push rods. The two first springs are respectively mounted on the two push rods. The top ends of the two first springs are fixedly connected to the positioning platform, and the bottom ends are fixedly connected to the resistance block.

[0014] Furthermore, a pressure control mechanism is installed on the top of the equipment platform, and the pressure control mechanism is used to prevent the circular mold in the test mold from shifting and jumping when the aggregate is impacted;

[0015] The pressure control mechanism includes a lifting plate and two groups of pressure control units, which are respectively installed at the two end positions of the lifting plate. Each group of pressure control units includes three elastic claws distributed in a fan shape. Each of the elastic claws includes a sliding rod, a U-shaped claw and a second spring. The sliding rod passes through and is slidably installed on the lifting plate. The U-shaped claw is fixedly installed on the bottom end of the sliding rod. The second spring is sleeved on the sliding rod. The top end of the second spring is fixedly connected to the lifting plate, and the bottom end is fixedly connected to the U-shaped claw.

[0016] Preferably, a pressure rod is fixedly mounted on one side outer wall of the lifting carrier plate.

[0017] In order to solve the above problems, the present invention also provides a test method for aggregate crushing value test, comprising the following steps:

[0018] T1: Screen the aggregate to remove particles that do not meet the particle size requirements, and weigh the specified mass of aggregate as the test sample;

[0019] T2: Place the round mold in the test mold into the round groove on the bottom plate, and then pour the weighed aggregate into the round groove;

[0020] T3: Shake the test mold left and right 25 times to compact the aggregate, then press the indenter in the test mold into the round mold;

[0021] T4: Place the trial mold in the positioning slot on the positioning table, then start the transfer mechanism to move the trial mold to the predetermined position in the press;

[0022] T5: Start the press and apply pressure to the indenter of the test mold at the set loading rate until the maximum test load is reached and maintain it for the specified time;

[0023] T6: After the specified time is reached, stop loading the press and slowly unload the pressure to return the press head to its initial position;

[0024] T7: Start the transfer mechanism, reset the positioning table to its initial position, and then take out the test mold;

[0025] T8: Pour the crushed aggregate in the test mold into a standard sieve and sieve to separate particles that meet the specified particle size requirements;

[0026] T9: Weigh the mass of the aggregate under the sieve, calculate the crushing value of the aggregate according to the crushing value calculation formula in the test standard, and record the test results.

[0027] Compared with related technologies, the pressure testing device and test method for aggregate crushing value testing provided by the present invention have the following beneficial effects:

[0028] The present invention provides a pressure testing device for aggregate crushing value testing. By arranging a moving mechanism, a supporting block, and a positioning block, the horizontal and vertical positions of a test mold can be ensured to be accurately located, so that the axis of the test mold does not deviate too much from the axis of the pressure head of a press, and the test mold placement accuracy is high. At the same time, the tester can place the test mold in the positioning groove of the positioning holding table on the right side of the equipment platform, and the test mold is sent into the press by the transfer mechanism. There is no need to approach the press when applying pressure, thereby avoiding safety risks during operation and having the advantage of high safety.

[0029] The present invention provides a pressure testing device for aggregate crushing value testing, which is provided with an impact mechanism composed of a power component and two push components, and the phase difference of the two cams on the power component is 180 degrees. During the cyclic rotation, the push rods and the resisting blocks on the two push components are alternately pushed up, which can realize left and right cyclic impact on the aggregate in the test mold, so that the aggregate is automatically and evenly compacted under the action of gravity and impact force, and there is no need for test personnel to manually perform the impact operation, which can greatly reduce the labor intensity of the test personnel and avoid problems such as uneven manual impact force and position deviation, which is conducive to improving the consistency of aggregate density and test accuracy; combined with the setting of the pressure control mechanism, during the impact process, the pressure control mechanism exerts an elastic holding force on the circular mold through the cooperation of the U-shaped claw and the second spring, which does not affect the impact movement of the circular mold while limiting the displacement and jumping of the circular mold, thereby effectively improving the reliability of the device;

[0030] The present invention provides a test method for aggregate crushing value test. The test method is carried out by using the above-mentioned pressure test device for aggregate crushing value test, which can effectively reduce manpower input and improve the accuracy of test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic structural diagram of a first embodiment of a pressure testing device for aggregate crushing value testing provided by the present invention;

[0032] Figure 2 for Figure 1 The structural diagram of the transfer mechanism shown;

[0033] Figure 3 for Figure 2 The assembly diagram of the transfer plate and the positioning and placing table shown;

[0034] Figure 4 for Figure 1 The schematic diagram of the positioning holding table shown is placed on the support block;

[0035] Figure 5 A schematic structural diagram of a second embodiment of a pressure testing device for aggregate crushing value testing provided by the present invention;

[0036] Figure 6 for Figure 5 Schematic diagram of part of the structure shown;

[0037] Figure 7 for Figure 5 The structural diagram of the pressure control mechanism shown;

[0038] Figure 8 for Figure 7 The distribution diagram of the elastic claw members shown;

[0039] Figure 9for Figure 5 The schematic diagram of the cooperation between the power assembly and the two push assemblies shown;

[0040] Figure 10 for Figure 5 The schematic structural diagram of the push assembly shown;

[0041] Figure 11 for Figure 5 The schematic diagram of the pressure control mechanism shown is in working state.

[0042] Numbers in the figure: 1. Equipment platform; 2. Pad; 3. Press; 4. Support block; 5. Positioning block; 6. Moving carrier; 7. Screw; 8. First motor; 9. Fixed column; 10. Support circular plate; 11. I-bench; 12. First hydraulic cylinder; 13. Mounting seat; 14. Transfer plate; 141. Front end support bar; 15. Positioning holding platform; 16. Rack; 17. Second motor; 18. Gear; 19. Push rod; 20. Resistance block; 21. First spring; 22. Rotating shaft; 23. Cam; 24. Third motor; 25. Support frame; 26. Second hydraulic cylinder; 27. Lifting carrier; 28. Slide rod; 29. ​​U-shaped claw; 30. Second spring; 31. Guide rod; 32. Pressure rod. DETAILED DESCRIPTION

[0043] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0044] First embodiment

[0045] Please refer to Figures 1-4 In the first embodiment of the present invention, the pressure test device for aggregate crushing value test includes: an equipment platform 1, a pad 2 and a press 3. The pad 2 is fixedly installed on the top of the equipment platform 1, and the press 3 is fixedly installed on the top of the pad 2. The structure of the press 3 adopts the conventional design of the hydraulic press in the prior art. Three support blocks 4 are fixedly installed on the top of the pad 2. The three support blocks 4 are distributed at equal intervals. An avoidance interval is formed between any two adjacent support blocks 4 for avoiding the front end support bar 141 on the transfer plate 14 mentioned below. A transfer mechanism is provided on the equipment platform 1. The conveying mechanism includes a lifting component and a moving component. The lifting component is used to adjust the height of the moving component. A positioning placing platform 15 is installed on the moving component. The moving component is used to move the positioning placing platform 15 to the top of the three support blocks 4. A positioning groove is provided on the top of the positioning placing platform 15. The positioning groove is used to place a test mold for the aggregate crushing value test. The diameter of the positioning groove is 0.8-1 cm larger than the diameter of the chassis of the test mold, which makes it convenient to place or take the test mold. At the same time, after the positioning placing platform 15 is moved to the predetermined position by the conveying mechanism, the test mold will not be excessively offset relative to the pressure head of the press 3.

[0046] In order to facilitate the test personnel to place the test mold into the positioning groove, a square opening is opened on the pad 2, and a movable carrier 6 is slidably installed in the square opening. The movable assembly is installed on the movable carrier 6, and a screw rod 7 is rotatably installed in the square opening. The screw rod 7 passes through the movable carrier 6 and is threadedly connected to the movable carrier 6. A first motor 8 is fixedly installed on one side of the equipment platform 1. One end of the screw rod 7 extends to the outside of the equipment platform 1 and is fixedly connected to the output end of the first motor 8. After the first motor 8 is running, it drives the screw rod 7 to rotate, and the movable carrier 6 is driven to move left or right by the spiral pushing action of the screw rod 7. After the movable carrier 6 moves to the right to the extreme position, the relevant test personnel can place the test mold in the positioning groove on the positioning holding table 15 on the right side of the equipment platform 1.

[0047] In this embodiment, the lifting assembly specifically includes a plurality of fixed columns 9, a supporting circular plate 10, an I-beam 11 and a first hydraulic cylinder 12. The plurality of fixed columns 9 are fixedly mounted on the bottom of the movable carrier plate 6. The supporting circular plate 10 is fixedly mounted on the bottom ends of the plurality of fixed columns 9. The I-beam 11 includes an upper disc, a lower disc and an intermediate cylinder. The lower disc is slidably sleeved on the plurality of fixed columns 9. The intermediate cylinder passes through the movable carrier plate 6 and is slidably connected to the movable carrier plate 6. The upper disc at the top of the I-beam 11 is located above the equipment platform 1. The first hydraulic cylinder 12 is fixedly mounted on the top of the supporting circular plate 10. The output end of the first hydraulic cylinder 12 is fixedly connected to the bottom of the I-beam 11. A positioning ring is fixedly sleeved on the outer wall of each fixed column 9 to limit the maximum rising distance of the I-beam 11.

[0048] The moving assembly specifically includes a mounting base 13, a transfer plate 14, a rack 16, a second motor 17 and a gear 18. The mounting base 13 is fixedly mounted on the top of the upper disc of the I-beam 11, the transfer plate 14 is penetrated and slidably mounted on the mounting base 13, the rack 16 is fixedly mounted on the top of the transfer plate 14, the second motor 17 is fixedly mounted on the mounting base 13, the gear 18 is fixedly sleeved on the output end of the second motor 17, and the gear 18 is meshed with the rack 16. The transfer plate 14 is close to the press 3 and is integrally formed with two front End support bar 141, the minimum distance between the two front support bars 141 is greater than the width of the support block 4 in the middle, and two limiting round rods are fixedly installed on the top of the two front support bars 141. The positioning holding platform 15 is slidably sleeved on the four limiting round rods. The transfer plate 14 moves forward a certain distance and then is lowered. The two front support bars 141 will respectively enter the two avoidance intervals, and then the positioning holding platform 15 will be placed on the top of the three support blocks 4. When conducting the test, the three support blocks 4 support the positioning holding platform 15.

[0049] In this embodiment, in order to be able to position the forward position of the transfer plate 14, two positioning blocks 5 are fixedly installed on the top of the pad 2. When the two front end support bars 141 respectively conflict with the two positioning blocks 5, the positioning holding platform 15 has reached the predetermined lateral position at this time, and then it can be lowered onto the three support blocks 4. Since the test mold is located in the positioning groove of the positioning holding platform 15, the lateral position of the test mold can also be accurately found (the axis center line of the test mold will not deviate too much from the axis center line of the pressure head of the press 3).

[0050] In this embodiment:

[0051] During use, the first motor 8 drives the screw rod 7 to rotate forward, which can drive the movable carrier plate 6 to move to the right. The transfer mechanism follows the movement of the movable carrier plate 6 and finally moves to the right side of the equipment platform 1. After the relevant test personnel pour the aggregate into the circular mold of the test mold and complete the shaking, they can then easily place the test mold in the positioning groove of the positioning holding table 15.

[0052] After the placement of the test mold is completed, the first motor 8 is started to run, driving the screw rod 7 to rotate in the opposite direction. During the reverse rotation of the screw rod 7, the movable carrier plate 6 is driven to move to the left, and finally the movable carrier plate 6 is reset. Then the second motor 17 is started to run, driving the gear 18 to rotate counterclockwise. The counterclockwise rotating gear 18 pushes the rack 16 to move forward, so that the transfer plate 14 continues to move forward. The transfer plate 14 drives the positioning holding platform 15 and the test mold containing the aggregate to move. When the two front end support bars 141 on the transfer plate 14 respectively conflict with the two positioning blocks 5, the second motor 17 is turned off. At this time, the lateral position of the positioning holding platform 15 is found, and then the output end of the first hydraulic cylinder 12 is started to retract, and the first hydraulic cylinder 12 drives the I-beam 11 moves downward, the I-beam 11 will drive the moving component to move downward, and the two front support bars 141 will respectively enter the avoidance interval between the corresponding two support blocks 4. As the front support bar 141 continues to descend, the positioning holding platform 15 stays on the three support blocks 4. In this way, the positioning holding platform 15 can be reliably supported, and its longitudinal position can also be accurately found. When the position of the positioning holding platform 15 is accurately found, the position of the test mold in the positioning groove is also accurately found. Thereafter, the specified pressure can be applied to the pressure head of the test mold through the press 3 according to the test requirements. Since the test mold is sent into the press 3 through the transfer mechanism, it is relatively safe, and the position of the test mold is also found more accurately, which can make the aggregate force more uniform.

[0053] Second embodiment:

[0054] The second embodiment of the present invention will be further described below with reference to the accompanying drawings and implementation plans.

[0055] Please refer to Figure 5-Figure 11In the pressure testing device for aggregate crushing value test provided in this embodiment, a striking mechanism for striking the test mold for aggregate crushing value test is also provided on the movable carrier plate 6 and the positioning holding platform 15. The striking mechanism includes a power assembly and two pushing assemblies. The two pushing assemblies are both installed on the positioning holding platform 15 and are respectively located on both sides of the transfer plate 14. The power assembly is installed on the movable carrier plate 6.

[0056] Specifically, the power assembly includes a rotating shaft 22, two cams 23, and a third motor 24. The rotating shaft 22 is rotatably mounted on the top of the movable carrier 6. The two cams 23 are fixedly mounted on the rotating shaft 22. The movable carrier 6 has two avoidance openings, each for avoiding the two cams 23. The phase difference between the two cams 23 is 180 degrees. The third motor 24 is fixedly mounted on the top of the movable carrier 6. The output end of the third motor 24 is fixedly connected to one end of the corresponding rotating shaft 22.

[0057] Any push assembly includes two push rods 19, a resisting block 20 and two first springs 21. A smooth hole connected to the positioning groove is provided at the bottom of the positioning holding platform 15. The two push rods 19 are slidably installed in the corresponding smooth holes. The resisting block 20 is fixedly installed at the bottom ends of the two push rods 19. The two first springs 21 are respectively sleeved on the two push rods 19. The top ends of the two first springs 21 are fixedly connected to the positioning holding platform 15, and the bottom ends are fixedly connected to the resisting block 20. The two cams 23 push the two resisting blocks 20 respectively. The protruding part of the cam 23 pushes the resisting block 20 to move upward during the process of rotating from bottom to top. The resisting block 20 drives the two push rods 19 to slide upward. Under the push of the two push rods 19, the test mold The corresponding side of the chassis will be lifted up, and when the cam 23 is separated from the resisting block 20, under the action of gravity and the elastic force of the first spring 21, the two push rods 19 will reset downward, and the chassis of the test mold will also fall flat, and the aggregate in the circular mold of the test mold will be lifted and then fall. When falling, the particles are affected by gravity and hit the bottom of the test mold or other particles, generating an impact force, which prompts the aggregate particles to be more densely stacked, thereby playing a knocking role. Since the phase difference between the two cams 23 is 180°, when one of the cams 23 conflicts with the corresponding resisting block 20, the other cam 23 is in a separated state from the corresponding resisting block 20, so that the left and right cyclic knocking of the aggregate in the test mold can be achieved, so that the aggregate in the test mold can become uniform and dense;

[0058] In this embodiment, a pressure control mechanism is also installed on the top of the equipment platform 1. The pressure control mechanism is used to prevent the circular mold in the test mold from shifting and jumping when the aggregate is bumped. Specifically, the pressure control mechanism includes a lifting plate 27 and two sets of pressure control units, and also includes a support frame 25, a second hydraulic cylinder 26 and two guide rods 31. The support frame 25 is fixedly installed on the top of the equipment platform 1, and the second hydraulic cylinder 26 is fixedly installed on the top of the support frame 25. The output end of the second hydraulic cylinder 26 extends into the support frame 25 and is fixedly connected to the lifting plate 27. The two guide rods 31 are both penetrated and slidably installed on the support frame 25, and the bottom of the two guide rods 31 is fixedly installed on the top of the two guide rods 31. The ends are fixedly connected to the lifting carrier plate 27, and the two groups of pressure control units are respectively installed at the two end positions of the lifting carrier plate 27. Each group of pressure control units includes three elastic claws distributed in a fan shape, and each elastic claw includes a slide bar 28, a U-shaped claw 29 and a second spring 30. The slide bar 28 passes through and is slidably installed on the lifting carrier plate 27. The U-shaped claw 29 is fixedly installed at the bottom end of the slide bar 28. The opening direction of the U-shaped claw 29 is toward the circular mold, and the width of the opening is greater than the wall thickness of the circular mold. The second spring 30 is sleeved on the slide bar 28. The top end of the second spring 30 is fixedly connected to the lifting carrier plate 27, and the bottom end is fixedly connected to the U-shaped claw 29.

[0059] In order to limit the upward movement of the positioning holding platform 15 during the impact process, a pressure rod 32 is fixedly installed on the outer wall of one side of the lifting plate 27. When the second hydraulic cylinder 26 drives the lifting plate 27 to move downward, the U-shaped claw 29 is first stuck on the top of the circular mold, and then the lifting plate 27 continues to descend. The U-shaped claw 29 will rise relative to the lifting plate 27, and the second spring 30 will be compressed. Then the bottom end of the pressure rod 32 will conflict with the top of the positioning holding platform 15.

[0060] In this embodiment:

[0061] Since the movable carrier plate 6 and the positioning holding platform 15 are provided with a knocking mechanism, the relevant test personnel can place the test mold in the positioning groove on the positioning holding platform 15 after filling the aggregate into the cylinder of the test mold to knock it, so as to make the aggregate in the round mold uniform and dense. The specific operation is as follows: place the test mold containing the aggregate (the pressure head of the test mold is not placed in the round mold first) in the positioning groove, and then start the output end of the second hydraulic cylinder 26 in the pressure control mechanism to extend downward, and the second hydraulic cylinder 26 drives the lifting carrier plate 27 to move downward. The lifting plate 27 drives the two sets of pressure control units and the pressure rod 32 on itself to move downward, and the U-shaped claws 29 on the two sets of pressure control units are both stuck on the top of the circular mold. Then the lifting plate 27 continues to descend for a distance, so that the bottom end of the pressure rod 32 conflicts with the top of the positioning holding platform 15. In this way, the positioning holding platform 15 cannot move up due to the restriction of the pressure rod 32, and the reverse elastic force of the compressed second spring 30 acts on the top of the circular mold through the U-shaped claw 29, so that the circular mold is restricted. After starting the third motor 24, The two cams 23 on the rotating shaft 22 are driven to rotate cyclically. The two cams 23 will alternately conflict with the corresponding resisting blocks 20. The resisting blocks 20 will rise when they are resisted, and the two push rods 19 will push one side of the chassis of the corresponding test mold to tilt up. As one side of the circular mold follows the chassis to tilt up, the corresponding U-shaped claw 29 will rise accordingly. However, the elastic pressure of the second spring 30 will always give the circular mold limiting pressure. Combined with the limiting effect of the circular groove on the chassis of the test mold on the circular mold, the circular mold can be moved forward without hindering the progress of the circular mold. During the impact movement, it can be ensured that the circular mold will not be displaced or jump; when the cam 23 is separated from the resistance block 20, the two push rods 19 will reset downward, and the chassis of the test mold will also fall flat, generating an impact force, which will cause the aggregate particles to stack more densely. Since the phase difference between the two cams 23 is 180°, the two resistance blocks 20 will be alternately impacted, so that the left and right sides of the test mold can alternately rise and fall, thereby realizing the left and right cyclic impact on the aggregate in the test mold, so that the aggregate in the test mold can become uniform and dense.

[0062] Third embodiment:

[0063] This embodiment provides a test method for aggregate crushing value test, comprising the following steps:

[0064] T1: Screen the aggregate to remove particles that do not meet the particle size requirements, and weigh the specified mass of aggregate as the test sample;

[0065] T2: Place the round mold in the test mold into the round groove on the bottom plate, and then pour the weighed aggregate into the round groove;

[0066] T3: Shake the test mold left and right 25 times to compact the aggregate, then press the indenter in the test mold into the round mold;

[0067] T4: Place the trial mold in the positioning groove on the positioning holding table 15, and then start the transfer mechanism to move the trial mold to the predetermined position in the press 3;

[0068] T5: Start the press 3 and apply pressure to the indenter of the test mold at the set loading rate until the maximum test load is reached and maintain it for the specified time;

[0069] T6: After the specified time is reached, stop loading the press 3 and slowly unload the pressure to return the press head to its initial position;

[0070] T7: Start the transfer mechanism to reset the positioning table 15 to its initial position, and then take out the test mold;

[0071] T8: Pour the crushed aggregate in the test mold into a standard sieve and sieve to separate particles that meet the specified particle size requirements;

[0072] T9: Weigh the mass of the aggregate under the sieve, calculate the crushing value of the aggregate according to the crushing value calculation formula in the test standard, and record the test results.

[0073] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A pressure test device for aggregate crushing value test, comprising an equipment platform, a pad and a press, wherein the pad is fixedly mounted on the top of the equipment platform, and the press is fixedly mounted on the top of the pad, characterized in that: Three support blocks are fixedly installed on the top of the pad, and a transfer mechanism is provided on the equipment platform. The transfer mechanism includes a lifting component and a moving component. The lifting component is used to adjust the height of the moving component. A positioning placing platform is installed on the moving component. The moving component is used to move the positioning placing platform to above the three support blocks. A positioning groove is provided on the top of the positioning placing platform, and the positioning groove is used to place a test mold for an aggregate crushing value test. The pad is provided with a square opening, in which a movable carrier is slidably installed, the movable assembly is mounted on the movable carrier, a screw is rotatably mounted in the square opening, the screw passes through the movable carrier and is threadedly connected to the movable carrier, a first motor is fixedly mounted on one side of the equipment platform, one end of the screw extends outside the equipment platform and is fixedly connected to the output end of the first motor; The movable carrier plate and the positioning and placing table are further provided with an impact mechanism for impacting the test mold for the aggregate crushing value test, the impact mechanism comprising a power assembly and two pushing assemblies, the two pushing assemblies are both mounted on the positioning and placing table and are respectively located on both sides of the movable assembly, the power assembly is mounted on the movable carrier plate; The power assembly includes a rotating shaft, two cams, and a third motor. The rotating shaft is rotatably mounted on the top of the movable carrier. The two cams are fixedly mounted on the rotating shaft, and the phase difference between the two cams is 180 degrees. The third motor is fixedly mounted on the top of the movable carrier, and the output end of the third motor is fixedly connected to one end of the corresponding rotating shaft. Any of the pushing assemblies includes two push rods, a resisting block and two first springs. A smooth hole connected to the positioning groove is provided at the bottom of the positioning table. The two push rods are slidably installed in the corresponding smooth holes. The resisting block is fixedly installed at the bottom ends of the two push rods. The two first springs are respectively sleeved on the two push rods. The top ends of the two first springs are fixedly connected to the positioning table, and the bottom ends are fixedly connected to the resisting block. A pressure control mechanism is also installed on the top of the equipment platform, and the pressure control mechanism is used to prevent the circular mold in the test mold from shifting and jumping when the aggregate is impacted; The pressure control mechanism includes a lifting plate and two groups of pressure control units, which are respectively installed at the two end positions of the lifting plate. Each group of pressure control units includes three elastic claws distributed in a fan shape. Each of the elastic claws includes a sliding rod, a U-shaped claw and a second spring. The sliding rod passes through and is slidably installed on the lifting plate. The U-shaped claw is fixedly installed on the bottom end of the sliding rod. The second spring is sleeved on the sliding rod. The top end of the second spring is fixedly connected to the lifting plate, and the bottom end is fixedly connected to the U-shaped claw.

2. The pressure testing device for aggregate crushing value test according to claim 1, characterized in that: The lifting assembly includes multiple fixed columns, a supporting circular plate, an I-bench and a first hydraulic cylinder. The multiple fixed columns are fixedly installed on the bottom of the movable carrier plate. The supporting circular plate is fixedly installed on the bottom ends of the multiple fixed columns. The I-bench is slidably sleeved on the multiple fixed columns. The top of the I-bench extends above the equipment platform. The first hydraulic cylinder is fixedly installed on the top of the supporting circular plate. The output end of the first hydraulic cylinder is fixedly connected to the bottom of the I-bench.

3. The pressure testing device for aggregate crushing value test according to claim 2, characterized in that: The moving assembly includes a mounting seat, a transfer plate, a rack, a second motor and a gear. The mounting seat is fixedly mounted on the top of the I-beam, the transfer plate passes through and is slidably mounted on the mounting seat, the rack is fixedly mounted on the top of the transfer plate, the second motor is fixedly mounted on the mounting seat, the gear is fixedly sleeved on the output end of the second motor, and the gear is meshed with the rack. The transfer plate is close to the press and is integrally formed with two front end support bars. Two limiting round rods are fixedly mounted on the top of the two front end support bars, and the positioning holding platform is slidably sleeved on the four limiting round rods.

4. The pressure testing device for aggregate crushing value test according to claim 1, characterized in that: Two positioning blocks are fixedly installed on the top of the pad.

5. The pressure testing device for aggregate crushing value test according to claim 1, characterized in that: A pressure rod is fixedly installed on one side outer wall of the lifting carrier plate.

6. A test method for aggregate crushing value test, characterized in that: The test is carried out using the pressure testing device for aggregate crushing value test according to any one of claims 1 to 5, comprising the following steps: T1: Screen the aggregate to remove particles that do not meet the particle size requirements, and weigh the specified mass of aggregate as the test sample; T2: Place the round mold in the test mold into the round groove on the bottom plate, and then pour the weighed aggregate into the round groove; T3: Shake the test mold left and right 25 times to compact the aggregate, then press the indenter in the test mold into the round mold; T4: Place the trial mold in the positioning slot on the positioning table, then start the transfer mechanism to move the trial mold to the predetermined position in the press; T5: Start the press and apply pressure to the indenter of the test mold at the set loading rate until the maximum test load is reached and maintain it for the specified time; T6: After the specified time is reached, stop loading the press and slowly unload the pressure to return the press head to its initial position; T7: Start the transfer mechanism, reset the positioning table to its initial position, and then take out the test mold; T8: Pour the crushed aggregate in the test mold into a standard sieve and sieve to separate particles that meet the specified particle size requirements; T9: Weigh the mass of the aggregate under the sieve, calculate the crushing value of the aggregate according to the crushing value calculation formula in the test standard, and record the test results.

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