A device and method for detecting the bearing capacity of a road subgrade

Abstract

The application provides a kind of road subgrade bearing capacity detection device and detection method, belong to road detection technical field.Detection device includes trailer type drop hammer deflection instrument, the bottom of the rack of trailer type drop hammer deflection instrument is equipped with horizontal moving mechanism, the bottom of horizontal moving mechanism is equipped with horizontal clear pushing mechanism.Detection method includes steps T2: start the operation of first hydraulic cylinder of horizontal clear pushing mechanism, push triangular push plate to move down to contact with subgrade surface, monitor contact pressure by first pressure sensor, stop moving down when reach predetermined value, then start the operation of horizontal moving mechanism, drive triangular push plate to move horizontally, clear and push protruding hard material on the surface of subgrade under displacement sensor.The road subgrade bearing capacity detection device provided by the application has the advantages of being able to efficiently clean protruding hard material on the surface of subgrade, being able to pre-clean debris to assist smooth clear pushing, and the cleaning brush being easy to replace.

Description

Technical Field

[0001] This invention relates to the field of road testing technology, and in particular to a road subgrade bearing capacity testing device and testing method. Background Technology

[0002] In the construction and maintenance of road engineering, the testing of the roadbed bearing capacity is a crucial step in ensuring road quality. The falling weight deflectometer, as a commonly used testing device, is widely applied to detect roadbed deflection values ​​and assess its bearing capacity due to its ability to simulate actual traffic load impacts. Existing falling weight deflectometers typically apply impact loads to the roadbed surface through a load plate and utilize multiple displacement sensors to collect deformation data. The contact state between the sensor contacts and the roadbed surface directly affects the accuracy of the test data.

[0003] In actual testing environments, roadbed surfaces often contain protruding hard objects such as gravel, bricks, and hardened soil clods. However, existing falling weight deflectometers lack a dedicated cleaning mechanism for these protruding hard objects on the roadbed surface. This can easily cause the displacement sensor's contacts to directly contact these protruding hard objects, resulting in uneven force distribution on the contacts and an inability to accurately reflect the deformation of the roadbed under impact loads.

[0004] Therefore, it is necessary to provide a new road subgrade bearing capacity testing device and method to solve the above-mentioned technical problems. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a roadbed bearing capacity testing device and method that can efficiently clean protruding hard objects on the roadbed surface to improve testing accuracy, can pre-clean debris to facilitate smooth cleaning and pushing, and has easy-to-replace cleaning brushes to improve maintenance convenience.

[0006] To solve the above-mentioned technical problems, the present invention provides a road subgrade bearing capacity testing device, including a trailer-mounted falling weight deflectometer. A transverse movement mechanism is installed at the bottom of the frame of the trailer-mounted falling weight deflectometer, and a transverse cleaning mechanism is installed at the bottom of the transverse movement mechanism. The transverse cleaning mechanism is used to remove protruding hard objects on the subgrade surface.

[0007] The transverse cleaning and pushing mechanism includes a bearing plate, two guide slides, a lifting plate, a triangular push plate, and two first hydraulic cylinders. The two guide slides are both slidably mounted on the bearing plate. The lifting plate is fixedly mounted on the bottom end of the two guide slides. The triangular push plate is fixedly mounted on the bottom of the lifting plate. The maximum width of the triangular push plate is greater than the diameter of the load plate of the trailer-mounted falling weight deflectometer. The two first hydraulic cylinders are both fixedly mounted on the top of the bearing plate. Two first pressure sensors are fixedly mounted on the top of the lifting plate. The output ends of the two first hydraulic cylinders extend to the bottom of the bearing plate and are fixedly connected to the force-bearing surfaces of the two first pressure sensors, respectively.

[0008] Preferably, the lateral movement mechanism includes a U-shaped mounting box, a first electric motor, two lateral lead screws, a rotating shaft, and two lateral moving blocks. The U-shaped mounting box is fixedly installed at the bottom of the frame of the trailer-mounted falling weight deflectometer. Both lateral lead screws are rotatably installed inside the U-shaped mounting box. The first electric motor is fixedly installed at one end of the U-shaped mounting box, and the output end of the first electric motor is fixedly connected to the end of the corresponding lateral lead screw located outside the U-shaped mounting box. The ends of both lateral lead screws located inside the U-shaped mounting box are fixedly fitted with first bevel teeth. The rotating shaft is rotatably installed inside the U-shaped mounting box, and both ends of the rotating shaft are fixedly fitted with second bevel teeth. The two second bevel teeth respectively mesh with the two first bevel teeth. Both lateral moving blocks are slidably installed inside the U-shaped mounting box. Both lateral lead screws pass through the corresponding lateral moving blocks and are threadedly connected to the corresponding lateral moving blocks. The bottom of both lateral moving blocks is fixedly installed with a lifting rod, and the bottom end of both lifting rods is fixedly connected to the bearing plate.

[0009] Furthermore, the lateral cleaning and pushing mechanism also includes at least one set of auxiliary detection units for detecting whether the triangular push plate is in contact with the roadbed surface;

[0010] The auxiliary detection unit includes a lower fixed plate, a hexagonal push rod, an upper fixed plate, and a second pressure sensor. The lower and upper fixed plates are both fixedly mounted on the triangular push plate. The hexagonal push rod passes through and slides on the lower fixed plate. The second pressure sensor is fixedly mounted on the bottom of the upper fixed plate. The top end of the hexagonal push rod contacts the force-bearing surface of the second pressure sensor. An arc-shaped contact plate is fixedly mounted on the bottom end of the hexagonal push rod. The lowest edge of the arc-shaped contact plate is at the same horizontal level as the bottom surface of the triangular push plate. A limiting ring is fixedly sleeved on the outer side of the hexagonal push rod, and the limiting ring contacts the lower fixed plate.

[0011] Furthermore, a longitudinal pre-cleaning mechanism is also installed on the support plate. The longitudinal pre-cleaning mechanism includes a slide rail, a longitudinal lead screw, a second electric motor, a movable carrier plate, a square sliding plate, a second hydraulic cylinder, a third electric motor, and a cleaning brush. The slide rail is fixedly installed on the support plate, and side supports are fixedly installed at both ends of the slide rail. The longitudinal lead screw is rotatably installed on the two side supports. A longitudinal moving block is slidably installed on the slide rail. The longitudinal lead screw passes through the longitudinal moving block and is threadedly connected to the longitudinal moving block. The second electric motor is fixedly installed on one of the side supports, and the output end of the second electric motor is fixedly connected to one end of the corresponding longitudinal lead screw. The movable carrier plate is fixedly installed on the outer wall of the longitudinal moving block away from the support plate. The square sliding plate passes through and is slidably installed on the movable carrier plate. The third electric motor is fixedly installed on the square sliding plate. The cleaning brush is installed on the output end of the third electric motor. The second hydraulic cylinder is fixedly installed on the top of the movable carrier plate, and the output end of the second hydraulic cylinder extends to the bottom of the movable carrier plate and is fixedly connected to the square sliding plate.

[0012] Preferably, the square slide plate includes an upper slide plate, a lower slide plate, an upper fixing plate, and a lower fixing plate. The upper fixing plate is fixedly installed at the bottom of the upper slide plate, and the lower fixing plate is rotatably installed at the bottom of the upper fixing plate. The bottom of the lower fixing plate is fixedly connected to the top of the lower slide plate. The lower fixing plate has two insertion holes, which are 180° symmetrically rotated. The upper slide plate is provided with a locking member, which is used to lock the lower fixing plate by cooperating with the two insertion holes.

[0013] Preferably, the locking member includes a sliding plate and two pins. The sliding plate passes through and is slidably mounted on the upper sliding plate. The two pins are respectively fixedly mounted at both ends of the sliding plate. Both pins pass through the upper fixed plate and are slidably connected to the upper fixed plate. The bottom of both pins extends into the corresponding insertion hole.

[0014] Preferably, the connection between the bottom end face of the pin and the outer peripheral wall is designed with rounded corners.

[0015] Preferably, a mounting block is fixedly installed on the output end of the third electric motor. A slot is provided in the mounting block. An insert block is fixedly installed on the core rod of the cleaning brush near the end of the third electric motor. The insert block is located in the slot, and the top surface of the insert block is at the same level as the top surface of the mounting block. A stop bar is provided on the top of the mounting block, and the bottom of the stop bar contacts the top surface of the insert block. Fixed slide rods are provided on both sides of the mounting block. End blocks are fixedly installed at both ends of the fixed slide rods and are fixedly connected to the mounting block. Connecting sliders are slidably sleeved on both fixed slide rods. The tops of both connecting sliders are fixedly connected to the stop bar. Retaining springs are sleeved on both fixed slide rods. One end of each retaining spring is fixedly connected to the corresponding end block, and the other end is fixedly connected to the corresponding connecting slider.

[0016] Furthermore, the top of the baffle has a concave arc surface, and the inner wall of the concave arc surface has several anti-slip textures.

[0017] To address the above problems, the present invention also provides a method for detecting the bearing capacity of roadbeds, comprising the following steps:

[0018] T1: Move the falling weight deflectometer testing device to the subgrade area to be tested, and align the load plate and displacement sensor with the testing point;

[0019] T2: The first hydraulic cylinder of the lateral cleaning mechanism is activated, pushing the triangular push plate down to contact the roadbed surface. The contact pressure is monitored by the first pressure sensor. When the predetermined value is reached, the downward movement stops. Then, the lateral movement mechanism is activated, driving the triangular push plate to move laterally and cleaning the protruding hard objects on the roadbed surface below the displacement sensor.

[0020] T3: After the cleaning and pushing are completed, reset the lateral cleaning and pushing mechanism to ensure that it does not affect the operation of the load plate and displacement sensor;

[0021] T4: Controls the load plate of the trailer-mounted falling weight deflectometer to apply impact load to the roadbed surface, and collects roadbed surface deformation data through displacement sensors;

[0022] T5: Record the data collected by the displacement sensor and transmit it to the control terminal for analysis and processing to obtain the relevant test results of the roadbed bearing capacity.

[0023] Compared with related technologies, the road subgrade bearing capacity testing device and method provided by the present invention have the following advantages:

[0024] This invention provides a roadbed bearing capacity testing device. Through the arrangement of a lateral movement mechanism and a lateral cleaning mechanism, the lateral cleaning mechanism can move laterally under the drive of the lateral movement mechanism. During the movement, the triangular push plate on the lateral cleaning mechanism passes sequentially past multiple displacement sensors of a trailer-mounted falling weight deflectometer, pushing away protruding hard objects on the roadbed surface below the displacement sensors. This prevents the displacement sensor contacts from directly contacting the protruding hard objects during falling weight deflection testing. Simultaneously, as the two first hydraulic cylinders in the lateral cleaning mechanism push the triangular push plate into contact with the roadbed surface, the first hydraulic cylinders stop pushing when the pressure detected by the two first pressure sensors reaches a predetermined value. This prevents the triangular push plate from being pressed too deeply, affecting the original state of the roadbed surface. An auxiliary detection unit can help determine whether the triangular push plate is obstructed by hard objects. Through this cleaning and detection mechanism, the roadbed surface at the impact point of the falling weight is ensured to be flat and uniformly stressed, preventing data distortion caused by uneven stress on the displacement sensor contacts due to contact with hard objects, thus making the test results more accurate.

[0025] By setting up a longitudinal pre-sweeping mechanism, the roadbed surface directly below the triangular pusher can be scanned and cleaned in advance before the triangular pusher pushes, removing debris in advance. This greatly reduces the probability of the triangular pusher hitting protruding hard objects, allowing the triangular pusher to make reliable contact with the roadbed surface and thus complete the cleaning work more smoothly.

[0026] The cleaning brush features a quick-detachable design. With the rotating structure of the square slide, the cleaning brush can be rotated to the rear of the frame for replacement. Furthermore, the design of the baffle and the mounting block simplifies the disassembly and assembly steps of the cleaning brush, significantly improving the replacement efficiency and bringing convenience to the maintenance and use of the equipment.

[0027] This invention provides a method for testing the bearing capacity of roadbeds. This method can remove hard objects below the displacement sensor to avoid data distortion caused by the contact point coming into contact with hard objects, thereby ensuring the accuracy of the test. The lateral cleaning mechanism can operate automatically, reducing manual intervention and helping to improve operational efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the roadbed bearing capacity testing device provided by the present invention;

[0029] Figure 2 for Figure 1 A schematic diagram of the roadbed bearing capacity testing device from another perspective;

[0030] Figure 3 for Figure 2 A sectional view of the U-shaped mounting box from a bottom angle;

[0031] Figure 4 for Figure 2The diagram shows the structure of the transverse cleaning mechanism.

[0032] Figure 5 for Figure 4 A schematic diagram of the transverse cleaning mechanism from another perspective;

[0033] Figure 6 for Figure 5 The diagram shows the structure of the triangular push plate.

[0034] Figure 7 for Figure 6 The diagram shows the structure of the auxiliary detection unit.

[0035] Figure 8 for Figure 5 The diagram shows the structure of the longitudinal pre-cleaning mechanism.

[0036] Figure 9 for Figure 8 An exploded view of the square skateboard shown;

[0037] Figure 10 for Figure 9 The diagram shows the structure of the mounting block.

[0038] Numbering on the map:

[0039] 1. Trailer-mounted falling weight deflectometer; 2. U-shaped mounting box; 3. First electric motor; 4. Transverse lead screw; 5. Rotating shaft; 6. First bevel gear; 7. Second bevel gear; 8. Transverse moving block; 9. Lifting rod; 10. Bearing plate; 11. Guide slide column; 12. Lifting plate; 13. Triangular push plate; 14. First hydraulic cylinder; 15. First pressure sensor; 16. Lower fixed plate; 17. Hexagonal push rod; 18. Arc-shaped contact plate; 19. Limiting ring; 20. Upper fixed plate; 21. Second pressure sensor; 22. Slide rail; 23. Side support ; 24. Longitudinal lead screw; 25. Second electric motor; 26. Longitudinal moving block; 27. Moving carrier plate; 28. Square sliding plate; 29. ​​Second hydraulic cylinder; 30. Third electric motor; 31. Cleaning brush; 32. Mounting block; 33. Stop bar; 34. Insertion block; 35. Fixed slide bar; 36. Connecting slider; 37. End block; 38. Holding spring; 281. Upper sliding plate; 282. Lower sliding plate; 283. Upper fixed plate; 284. Lower fixed plate; 285. Sliding plate; 286. Pin; 2841. Insertion hole; 321. Slot. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0041] First embodiment:

[0042] Please refer to the following: Figures 1-10In the first embodiment of the present invention, a road subgrade bearing capacity testing device is proposed, which includes a trailer-mounted falling weight deflectometer 1. The trailer-mounted falling weight deflectometer 1 adopts the conventional design of the existing trailer-mounted falling weight deflectometer. It has multiple displacement sensors, with a displacement sensor at the center of the load plate. Other displacement sensors are arranged linearly with the sensor at the center. A transverse movement mechanism is installed at the bottom of the frame of the trailer-mounted falling weight deflectometer 1. A transverse cleaning mechanism is installed at the bottom of the transverse movement mechanism. The transverse cleaning mechanism is used to remove protruding hard objects on the subgrade surface.

[0043] The lateral clearing mechanism includes a bearing plate 10, two guide columns 11, a lifting plate 12, a triangular pusher plate 13, and two first hydraulic cylinders 14. The bearing plate 10 is located below the displacement sensor of the trailer-mounted falling weight deflectometer 1, ensuring it does not touch the displacement sensor during lateral movement. The two guide columns 11 are both slidably mounted on the bearing plate 10. The lifting plate 12 is fixedly mounted on the bottom of the two guide columns 11, and the triangular pusher plate 13 is fixedly mounted on the bottom of the lifting plate 12. The maximum width of the triangular pusher plate 13 is greater than the diameter of the load plate of the trailer-mounted falling weight deflectometer 1. During lateral movement, the triangular pusher plate 13 passes through multiple displacement sensors in sequence, pushing away protruding hard objects on the roadbed surface below the displacement sensors. This prevents the contacts of the displacement sensors from directly contacting the protruding hard objects, which could lead to excessive errors in the detection results. Two first hydraulic cylinders 14 are fixedly installed on the top of the support plate 10. Two first pressure sensors 15 are fixedly installed on the top of the lifting plate 12. The two first pressure sensors 15 are connected to the control terminal of the trailer-mounted falling weight deflectometer 1. The output ends of the two first hydraulic cylinders 14 extend to the bottom of the support plate 10 and are fixedly connected to the force-bearing surfaces of the two first pressure sensors 15 respectively. The two first hydraulic cylinders 14 and the two guide slides 11 are located on both sides of the load plate of the trailer-mounted falling weight deflectometer 1. During lateral movement, they will not touch the load plate. Under the push of the two first hydraulic cylinders 14, the triangular push plate 13 contacts the roadbed surface. When the pressure detected by the two first pressure sensors 15 reaches the predetermined value, the first hydraulic cylinders 14 stop pushing to avoid the triangular push plate 13 being pressed too deeply.

[0044] The transverse movement mechanism specifically includes a U-shaped mounting box 2, a first electric motor 3, two transverse lead screws 4, a rotating shaft 5, and two transverse moving blocks 8. The U-shaped mounting box 2 is fixedly installed at the bottom of the frame of the trailer-mounted falling weight deflectometer 1. Both transverse lead screws 4 are rotatably mounted inside the U-shaped mounting box 2. The first electric motor 3 is fixedly installed at one end of the U-shaped mounting box 2, and the output end of the first electric motor 3 is fixedly connected to the end of the corresponding transverse lead screw 4 located outside the U-shaped mounting box 2. The ends of both transverse lead screws 4 located inside the U-shaped mounting box 2 are each fixedly fitted with a first bevel tooth 6. The rotating shaft 5 is rotatably mounted inside the U-shaped mounting box 2, and both ends of the rotating shaft 5 are fixedly fitted with second bevel teeth 7. The two second bevel teeth 7 are respectively connected to... Two first bevel teeth 6 mesh with each other, and the cone apex directions of the two second bevel teeth 7 are consistent. Thus, when one of the transverse screws 4 rotates, it can drive the other transverse screw 4 to rotate simultaneously in the same direction under the meshing transmission of the two sets of second bevel teeth 7 and first bevel teeth 6. Both transverse moving blocks 8 are slidably installed in the U-shaped mounting box 2. Both transverse screws 4 pass through the corresponding transverse moving blocks 8 and are threadedly connected to the corresponding transverse moving blocks 8. Both transverse moving blocks 8 have hanging rods 9 fixedly installed at their bottoms. The bottom ends of both hanging rods 9 are fixedly connected to the bearing plate 10. The bottom cover of the U-shaped mounting box 2 has clearance strip openings. The two hanging rods 9 pass through the two clearance strip openings respectively and are movably connected to the inner wall of the clearance strip openings.

[0045] The transverse cleaning mechanism also includes at least one set of auxiliary detection units for detecting whether the triangular push plate 13 is in contact with the roadbed surface. In this embodiment, there are two auxiliary detection units, which are symmetrically installed on the triangular push plate 13.

[0046] Each auxiliary detection unit includes a lower fixed plate 16, a hexagonal push rod 17, an upper fixed plate 20, and a second pressure sensor 21. The lower fixed plate 16 and upper fixed plate 20 are both fixedly mounted on a triangular push plate 13. The hexagonal push rod 17 passes through and slides on the lower fixed plate 16. A hexagonal sliding hole is provided on the lower fixed plate 16, through which the hexagonal push rod 17 passes and slides against the inner wall of the hole. The second pressure sensor 21 is fixedly mounted on the bottom of the upper fixed plate 20 and is also connected to the control terminal of the trailer-mounted falling weight deflectometer 1. The top of the hexagonal push rod 17 contacts the force-bearing surface of the second pressure sensor 21. An arc-shaped contact plate 18 is fixedly mounted on the bottom of the hexagonal push rod 17. The lowest edge of the arc-shaped contact plate 18 is at the same horizontal level as the bottom surface of the triangular push plate 13. A limiting ring 19 is fixedly sleeved on the outer side of the hexagonal push rod 17. When the triangular push plate 13 comes into contact with the lower fixed plate 16 and abuts against the protruding hard object on the roadbed surface, the pressure values ​​detected by the two first pressure sensors 15 reach the set value. However, since the arc-shaped contact plates 18 on the two auxiliary detection units cannot effectively contact the roadbed surface, the two second pressure sensors 21 cannot detect pressure or the detected pressure is too small. In this case, it is determined that the triangular push plate 13 is obstructed by the hard object, and the protruding hard object below needs to be cleaned. When the roadbed surface below the triangular push plate 13 is relatively clean, the triangular push plate 13 will abut against the roadbed surface. Correspondingly, the bottom of the two arc-shaped contact plates 18 will also abut against the roadbed surface. After the pressure values ​​detected by the two first pressure sensors 15 reach the set value, the pressure values ​​detected by the two second pressure sensors 21 at this time will be approximately the same as the pressure values ​​detected by the first pressure sensors 15.

[0047] In this embodiment, before the triangular pusher plate 13 is pushed to contact the roadbed surface, a longitudinal pre-cleaning mechanism is installed on the bearing plate 10 to pre-clean the roadbed surface below the triangular pusher plate 13. Specifically, the longitudinal pre-cleaning mechanism includes a slide rail 22, a longitudinal lead screw 24, a second electric motor 25, a moving carrier plate 27, a square sliding plate 28, a second hydraulic cylinder 29, a third electric motor 30, and a cleaning brush 31. The slide rail 22 is fixedly installed on the bearing plate 10, and side supports 2 are fixedly installed at both ends of the slide rail 22. 3. A longitudinal lead screw 24 is rotatably mounted on two side supports 23. A longitudinal moving block 26 is slidably mounted on a slide rail 22. The longitudinal lead screw 24 passes through the longitudinal moving block 26 and is threadedly connected to the longitudinal moving block 26. A second electric motor 25 is fixedly mounted on one of the side supports 23. The output end of the second electric motor 25 is fixedly connected to one end of the corresponding longitudinal lead screw 24. A movable carrier plate 27 is fixedly mounted on the outer wall of the longitudinal moving block 26 on the side away from the carrier plate 10. A square sliding plate 28 passes through and is slidably mounted on the movable carrier plate 27. On plate 27, a third electric motor 30 is fixedly mounted on a square sliding plate 28. A sweeping brush 31 is mounted on the output end of the third electric motor 30. The sweeping brush 31 is cylindrical, with a core rod at its center and bristles on the outside. In its initial state, it is located on one side of the triangular push plate 13. A second hydraulic cylinder 29 is fixedly mounted on the top of the movable carrier plate 27. The output end of the second hydraulic cylinder 29 extends to the bottom of the movable carrier plate 27 and is fixedly connected to the square sliding plate 28. The second hydraulic cylinder 29 pushes the square sliding plate 28 downward, causing the sweeping brush to move downward. The bottom of 31 contacts the roadbed surface. After the third electric motor 30 runs, it drives the sweeping brush 31 to rotate. When the second electric motor 25 runs, it drives the longitudinal lead screw 24 to rotate. The longitudinal lead screw 24 spirally pushes the longitudinal moving block 26 to move axially. The moving carrier plate 27 and its components move with the longitudinal moving block 26, so that the sweeping brush 31 performs a scanning sweeping of the roadbed surface below the triangular push plate 13, and removes the debris on the roadbed surface in advance, greatly reducing the probability of the triangular push plate 13 hitting protruding hard objects.

[0048] In this embodiment, to facilitate the replacement of the cleaning brush 31, the square slide plate 28 includes an upper slide plate 281, a lower slide plate 282, an upper fixing plate 283, and a lower fixing plate 284. The upper fixing plate 283 is fixedly installed at the bottom of the upper slide plate 281, and the lower fixing plate 284 is rotatably installed at the bottom of the upper fixing plate 283. The bottom of the lower fixing plate 284 is fixedly connected to the top of the lower slide plate 282. The lower fixing plate 284 has two insertion holes 2841, which are 180° symmetrically rotated. The upper slide plate 281 is provided with a locking member, which is used to lock the lower fixing plate 284 by cooperating with the two insertion holes 2841. After the locking member releases the lower fixing plate 284, the lower slide plate 282 can be rotated 180°. This allows the cleaning brush 31, which was originally located below the frame of the trailer-mounted falling weight deflectometer 1, to be moved to the rear side of the frame, making it convenient to disassemble and assemble the cleaning brush 31.

[0049] Specifically, the locking component includes a sliding plate 285 and two pins 286. The sliding plate 285 passes through and slides on the upper sliding plate 281. The two pins 286 are fixedly installed at both ends of the sliding plate 285. Both pins 286 pass through the upper fixed plate 283 and are slidably connected to the upper fixed plate 283. The bottom of both pins 286 extends into the corresponding insertion hole 2841. In order to make the pins 286 more easily inserted into the insertion hole 2841, the connection between the bottom end face of the pin 286 and the outer peripheral wall is designed with rounded corners.

[0050] In this embodiment, to further improve the replacement efficiency of the sweeping brush 31, the sweeping brush 31 and the output end of the third electric motor 30 are designed to be quick-detachable. Specifically, a mounting block 32 is fixedly installed on the output end of the third electric motor 30, and a slot 321 is provided in the mounting block 32. A insertion block 34 is fixedly installed on the core rod of the sweeping brush 31 near the end of the third electric motor 30. The insertion block 34 is located in the slot 321, and the top surface of the insertion block 34 is at the same level as the top surface of the mounting block 32. A clearance opening communicating with the slot 321 is also provided on the front side of the mounting block 32 to allow the core rod of the sweeping brush 31 to pass. A stop bar 33 is provided on the top of the mounting block 32, and the bottom of the stop bar 33 contacts the top surface of the insertion block 34. Fixed sliding rods 35 are provided on both sides of the mounting block 32. Both ends of the fixed slide rod 35 are fixedly installed with end blocks 37, and the end blocks 37 are fixedly connected to the mounting block 32. Connecting sliders 36 are slidably sleeved on both fixed slide rods 35. The tops of the two connecting sliders 36 are fixedly connected to the stop strip 33. Retaining springs 38 are sleeved on both fixed slide rods 35. One end of the two retaining springs 38 is fixedly connected to the corresponding end block 37, and the other end is fixedly connected to the corresponding connecting slider 36. Under the retaining force of the two retaining springs 38, the stop strip 33 is always located above the mounting block 32, preventing the insert block 34 from slipping out of the slot 321. When the cleaning brush 31 needs to be replaced, drag the stop strip 33 backward to move it to the rear side of the slot 321, and then lift the core rod of the cleaning brush 31 upward to allow the insert block 34 to exit the slot 321.

[0051] To facilitate operation of the baffle 33, a concave arc surface is provided on the top of the baffle 33, and several anti-slip textures are provided on the inner wall of the concave arc surface.

[0052] In this embodiment:

[0053] Before inspection, the longitudinal pre-cleaning mechanism first pre-cleans the roadbed surface directly below the triangular push plate 13. During cleaning, the second hydraulic cylinder 29 is activated to push the square slide plate 28 downward, so that the bottom of the sweeping brush 31 contacts the roadbed surface. Then, the third electric motor 30 is activated to drive the sweeping brush 31 to rotate. At the same time, the second electric motor 25 is activated to drive the longitudinal lead screw 24 to rotate. Under the spiral push of the longitudinal lead screw 24, the longitudinal moving block 26 slides along the slide rail 22, driving the moving carrier plate 27 and the sweeping brush 31 to move accordingly. In this way, the roadbed surface below the triangular push plate 13 can be scanned and cleaned in advance to remove debris and reduce the probability of the triangular push plate 13 hitting protruding hard objects.

[0054] After the pre-cleaning is completed, the two first hydraulic cylinders 14 on the transverse cleaning mechanism are activated to push the lifting plate 12 down until the triangular push plate 13 contacts the roadbed surface. When the pressure detected by the first pressure sensor 15 reaches a predetermined value, the first hydraulic cylinder 14 stops pushing to prevent the triangular push plate 13 from being pressed too deeply. At the same time, the arc-shaped contact plate 18 of the auxiliary detection unit contacts the roadbed surface. If the pressure detected by the second pressure sensor 21 is similar to that of the first pressure sensor 15, it indicates that the triangular push plate 13 is in normal contact with the roadbed. If the second pressure sensor 21 does not detect pressure or the pressure is too low, it is determined that the triangular push plate 13 is obstructed by a hard object, and the hard object under the triangular push plate 13 needs to be properly removed manually. After the triangular push plate 13 is confirmed to be in good contact with the roadbed surface, the first electric motor 3 is activated. The corresponding transverse lead screw 4 is driven to rotate. Through the transmission of the first bevel tooth 6, the second bevel tooth 7 and the rotating shaft 5, the two transverse lead screws 4 rotate simultaneously in the same direction. The two transverse moving blocks 8 move along the transverse lead screw 4, and the bearing plate 10 moves laterally through the hanging rod 9. The triangular push plate 13 moves with the bearing plate 10 and passes through multiple displacement sensors in sequence, pushing away the protruding hard objects under the displacement sensors. The protruding hard objects will move to both sides along the two inclined sides of the triangular push plate 13, making the roadbed surface at the impact point of the drop hammer flat, ensuring uniform force, and preventing data distortion due to uneven force on the displacement sensor contacts. After cleaning, the drop hammer deflection detection work can be carried out. Since the protruding hard objects that may exist under each displacement sensor have been cleaned away in advance, the error of the detected data will be relatively small.

[0055] When the cleaning brush 31 needs to be replaced, lift the sliding plate 285 upwards to disengage the pins 286 from the insertion holes 2841 of the lower fixing plate 284. Then, rotate the lower sliding plate 282 180° and release the sliding plate 285. Under the action of gravity, the two pins 286 will re-insert into the two insertion holes 2841, locking the lower fixing plate 284 again. At this time, the cleaning brush 31 has been moved to the rear side of the frame. Then, drag the stop bar 33 to disengage it from the mounting block 34. After that, the cleaning brush 31 can be removed for replacement.

[0056] Second embodiment:

[0057] In a second embodiment of the present invention, a method for detecting the bearing capacity of a road subgrade is provided, comprising the following steps:

[0058] T1: Move the falling weight deflectometer testing device to the subgrade area to be tested, and align the load plate and displacement sensor with the testing point;

[0059] T2: The first hydraulic cylinder 14 of the lateral cleaning mechanism is activated, pushing the triangular push plate 13 down to contact the roadbed surface. The contact pressure is monitored by the first pressure sensor 15. When the pressure reaches the predetermined value, the downward movement stops. At the same time, the adhesion between the triangular push plate 13 and the roadbed surface is detected by the auxiliary detection unit. If the adhesion is normal, the lateral movement mechanism is activated to drive the triangular push plate 13 to move laterally and clean the protruding hard objects on the roadbed surface below the displacement sensor.

[0060] T3: After the cleaning and pushing are completed, reset the lateral cleaning and pushing mechanism to ensure that it does not affect the operation of the load plate and displacement sensor;

[0061] T4: Control the load plate of the trailer-mounted falling weight deflectometer 1 to apply impact load to the roadbed surface, and collect roadbed surface deformation data through displacement sensors;

[0062] T5: Record the data collected by the displacement sensor and transmit it to the control terminal for analysis and processing to obtain the relevant test results of the roadbed bearing capacity.

[0063] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A device for detecting the bearing capacity of a road subgrade, comprising a trailer-type falling weight deflectometer, characterized in that, The bottom of the frame of the trailer-type falling weight deflectometer is provided with a transverse moving mechanism, and the bottom of the transverse moving mechanism is provided with a transverse clearing mechanism for removing protruding hard objects on the surface of the roadbed. The transverse clearing mechanism comprises a bearing plate, two guide sliding columns, a lifting bearing plate, a triangular push plate and two first hydraulic cylinders, both of the guide sliding columns are penetratingly and slidingly installed on the bearing plate, the lifting bearing plate is fixedly installed at the bottom ends of the two guide sliding columns, the triangular push plate is fixedly installed at the bottom of the lifting bearing plate, the maximum width of the triangular push plate is greater than the diameter of the load plate of the trailer-type falling weight deflectometer, both of the first hydraulic cylinders are fixedly installed at the top of the bearing plate, the top of the lifting bearing plate is fixedly provided with two first pressure sensors, the output ends of both of the first hydraulic cylinders extend below the bearing plate and are fixedly connected with the force receiving surfaces of both of the first pressure sensors. The transverse clearing mechanism further comprises at least one set of auxiliary detection unit for detecting whether the triangular push plate is in contact with the surface of the roadbed. The auxiliary detection unit comprises a lower fixed plate, a hexagonal ejector rod, an upper fixed plate and a second pressure sensor, both of the lower fixed plate and the upper fixed plate are fixedly installed on the triangular push plate, the hexagonal ejector rod is penetratingly and slidingly installed on the lower fixed plate, the second pressure sensor is fixedly installed at the bottom of the upper fixed plate, the top end of the hexagonal ejector rod is in contact with the force receiving surface of the second pressure sensor, the bottom end of the hexagonal ejector rod is fixedly provided with an arc-shaped contact plate, the lowest edge of the arc-shaped contact plate is at the same horizontal level as the bottom surface of the triangular push plate, the outer side of the hexagonal ejector rod is fixedly provided with a limiting ring in contact with the lower fixed plate.

2. The road embankment bearing capacity detection device according to claim 1, characterized in that, The transverse moving mechanism comprises a U-shaped installation box, a first electric motor, two transverse lead screws, a rotating shaft and two transverse moving blocks, the U-shaped installation box is fixedly installed at the bottom of the frame of the trailer-type falling weight deflectometer, both of the transverse lead screws are rotatably installed in the U-shaped installation box, the first electric motor is fixedly installed at one end of the U-shaped installation box, the output end of the first electric motor is fixedly connected with the end of the corresponding transverse lead screw outside the U-shaped installation box, both of the transverse lead screws are fixedly provided with first bevel gears at the ends inside the U-shaped installation box, the rotating shaft is rotatably installed in the U-shaped installation box, both ends of the rotating shaft are fixedly provided with second bevel gears, both of the second bevel gears are engaged with the first bevel gears, both of the transverse moving blocks are slidingly installed in the U-shaped installation box, both of the transverse lead screws penetrate through the corresponding transverse moving blocks and are threadedly connected with the corresponding transverse moving blocks, both of the transverse moving blocks are fixedly provided with hanging rods at the bottoms, and both of the hanging rods are fixedly connected with the bearing plate at the bottom ends.

3. The road embankment bearing capacity detection device according to claim 1, characterized in that, The bearing plate is also provided with a longitudinal pre-cleaning mechanism, which comprises a sliding rail, a longitudinal screw rod, a second electric motor, a moving carrier plate, a square sliding plate, a second hydraulic cylinder, a third electric motor and a cleaning brush.

4. The road embankment bearing capacity detection device according to claim 3, characterized in that, The square sliding plate comprises an upper sliding plate, a lower sliding plate, an upper fixing disc and a lower fixing disc.

5. The road embankment bearing capacity detection device according to claim 4, characterized in that, The upper fixing disc is fixedly installed on the bottom of the upper sliding plate.

6. The road embankment bearing capacity detection device according to claim 5, characterized in that, The lower fixing disc is rotatably installed on the bottom of the upper fixing disc.

7. The road embankment bearing capacity detection device according to claim 3, characterized by, The bottom of the lower fixing disc is fixedly connected with the top of the lower sliding plate.

8. The road embankment bearing capacity detection device according to claim 7, characterized in that, The lower fixing disc is provided with two insertion holes. The two insertion holes are 180° rotationally symmetrical. The upper sliding plate is provided with a locking piece. The locking piece is used for locking the lower fixing disc. The locking piece comprises a sliding plate and two insertion pins. The sliding plate penetrates and is slidably installed on the upper sliding plate. The two insertion pins are fixedly installed on the two ends of the sliding plate. The two insertion pins penetrate the upper fixing disc and are slidably connected with the upper fixing disc. The bottom end surface of the insertion pin is designed as a round corner. The output end of the third electric motor is fixedly installed with a mounting block. The mounting block is provided with an insertion slot. The core rod of the cleaning brush is fixedly installed with an insertion block. The insertion block is located in the insertion slot. The top surface of the insertion block is located on the same horizontal plane with the top surface of the mounting block. The top of the mounting block is provided with a blocking strip. The bottom of the blocking strip is in contact with the top surface of the insertion block. The two sides of the mounting block are provided with fixed sliding rods. The two ends of the fixed sliding rod are fixedly installed with end blocks. The two ends of the fixed sliding rod are fixedly installed with end blocks. The two fixed sliding rods are slidably provided with connecting sliding blocks. The two fixed sliding rods are slidably provided with connecting sliding blocks. The two fixed sliding rods are provided with retaining springs. The two fixed sliding rods are provided with retaining springs. The top of the blocking strip is provided with a concave arc surface. The inner wall of the concave arc surface is provided with a plurality of anti-skid lines.

9. A method for detecting the load bearing capacity of a road subgrade, characterized by The road subgrade bearing capacity detection device according to any one of claims 1-8 is used for detection, and the detection comprises the following steps: T1: moving the falling weight deflectometer detection device to a to-be-detected subgrade region, and aligning the load plate and the displacement sensor with a detection point; T2: starting the first hydraulic cylinder of the transverse pushing mechanism to operate, pushing the triangular pushing plate to move downward to contact the surface of the subgrade, monitoring the contact pressure through the first pressure sensor, stopping the downward movement when the predetermined value is reached, and then starting the transverse moving mechanism to operate, driving the triangular pushing plate to move transversely to push away the protruding hard objects on the surface of the subgrade below the displacement sensor; T3: after the pushing away is completed, the transverse pushing mechanism is reset to ensure that it does not affect the operation of the load plate and the displacement sensor; T4: controlling the load plate of the trailer-type falling weight deflectometer to apply an impact load to the surface of the subgrade, and collecting deformation data of the surface of the subgrade through the displacement sensor; T5: recording the data collected by the displacement sensor, and transmitting the data to a control terminal for analysis and processing to obtain detection results related to the bearing capacity of the subgrade.

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