Asphalt pavement material fatigue test equipment based on pressure change

Abstract

The invention discloses asphalt pavement material fatigue test equipment based on pressure change, and relates to the technical field of fatigue test. Comprising a bearing assembly used for being assembled with a pressure applying assembly and a vehicle body running outside an asphalt pavement; and the pressure applying assembly is mounted at the bottom of the outer side of the bearing assembly and is used for carrying out a fatigue test of pressure change on the asphalt pavement material. According to the device, pressure is applied discontinuously in the testing process, an intermittent pressurizing mode is adopted, the situation that the testing result is affected by the over-elastic effect generated by continuous pressing of the asphalt pavement is effectively avoided, and in addition, through intermittent matching between a contact structure and a threaded lead screw structure, the testing result is more accurate. The asphalt pavement material can obtain a short recovery period after test pressurization, the recovery period is closer to the stress state in actual use, the damage to the asphalt pavement in the test process is reduced to a certain extent, and the consumed service life of the asphalt pavement material due to test is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of fatigue testing, in particular to a fatigue testing device for asphalt pavement materials based on pressure variation. Background Art

[0002] In the field of road engineering material research and development, it is crucial to evaluate the performance of asphalt pavement materials prepared by different formulations and processes. Therefore, it is urgent to develop an asphalt pavement material fatigue test equipment based on pressure changes.

[0003] After searching, the Chinese invention patent with publication number "CN113959857A" announced a "fatigue test device for composite materials at different temperatures and its use method". The device realizes the integrated transmission of composite materials in two sets of test boxes through the coordinated work of an integrated transmission mechanism and a composite material fixing and matching mechanism, meeting the needs of integrated testing of composite materials under different temperature environments.

[0004] In addition, the Chinese invention patent with publication number "CN114624133A" discloses a "material fatigue strength test device and material fatigue strength test method". This method connects one end of the material to be tested to the inner wall of the test chamber and the other end to the first piston, and delivers hydrogen energy to the booster through a fluid supply source. The hydrogen energy is supplied to the stretching chamber and the compression chamber after being pressurized, simulating the use environment of the material to be tested under actual working conditions. Based on the difference in hydrogen supply pressure and the delivery of hydrogen energy to the stretching chamber or the compression chamber, the strain of the material to be tested under different conditions can be measured, and then the fatigue strength of the material can be evaluated to characterize the performance of the material during the hydrogen energy delivery process, thereby preventing potential catastrophic consequences.

[0005] However, in actual applications, asphalt pavement materials will undergo elastic deformation when subjected to pressure tests. When the pressure test is removed, the asphalt pavement materials will partially recover to their original shape. However, when the above-mentioned devices and methods and similar devices and methods are used to perform fatigue tests on asphalt pavement materials, due to the specifications and recovery time characteristics of the asphalt pavement materials, when testing asphalt pavement materials, the direct transmission pressurization method is difficult to accurately capture the elastic deformation and potential permanent deformation characteristics of the asphalt pavement materials under pressure, and the test parameters cannot be reasonably adjusted accordingly, resulting in the accuracy of the test results being affected to a certain extent. Summary of the invention

[0006] The purpose of the present invention is to provide an asphalt pavement material fatigue testing device based on pressure variation to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a fatigue testing device for asphalt pavement materials based on pressure change, comprising:

[0008] A load-bearing assembly for assembly with a pressure-applying assembly and a vehicle body for operation outside an asphalt road surface;

[0009] A pressure-applying assembly, installed at the outer bottom of the load-bearing assembly, used to perform a fatigue test of pressure changes on the asphalt pavement material;

[0010] A driving component is embedded in the interior of the bearing component and is used to push the pressure component to move toward the asphalt pavement material, and to allow the pressure component to continuously apply pressure to the asphalt pavement material during the movement;

[0011] The bearing assembly comprises:

[0012] A carrying frame, wherein both ends of the bottom of the carrying frame are respectively provided with frame openings for matching with the pressure-applying assembly, and a control panel is fixed to one end of the surface of the carrying frame;

[0013] The drive assembly comprises:

[0014] A driving source is installed outside the bearing assembly and is used to provide rotational power. The driving source is electrically connected to the control panel.

[0015] A threaded screw structure is arranged inside the bearing assembly and fixed to the driving source;

[0016] The contact structure is arranged at the periphery of the threaded screw structure, and the contact structure is caused to perform unidirectional linear displacement at the periphery of the threaded screw structure by the unidirectional rotation of the driving source, and the bottom of the contact structure is in contact with the top of the pressure component. The pressure component gradually applies pressure to the asphalt pavement material during the unidirectional displacement of the contact structure;

[0017] The contact structure comprises:

[0018] A carrier, a contact frame in contact with the top of the pressure assembly is fixed at the bottom of the carrier, a retention groove is provided at one end of the carrier, and retention notches are evenly distributed in the retention groove. An electromagnet is installed on the carrier at the inner wall of the retention groove opposite to the retention notch. A power supply component for driving the electromagnet is installed on the carrier based on the retention groove. An electromagnetic screw block that moves based on the operation of the power supply component is installed at the retention notch of the carrier, and the electromagnetic screw block is adapted to the periphery of the threaded screw structure, and contact covers for shielding the retention groove and controlling the connection and disconnection of the power supply component are installed on both sides of one end of the carrier surface;

[0019] A limiting shaft is arranged at a position near the threaded screw structure inside the bearing component, and shaft seats fixed to the inner wall of the bearing component are respectively fixed at two ends of the outside of the limiting shaft, and the other end of the carrying seat is sleeved outside the limiting shaft and movably connected to the limiting shaft, and a return spring is installed between the carrying seat and one of the shaft seats, and the return spring is used to return the carrying seat to the initial position of the unidirectional linear displacement when the power supply component is disconnected, and to reconnect the power supply component, so that the contact structure performs unidirectional linear displacement again.

[0020] As a further preferred embodiment of the present technical solution, the power supply component includes:

[0021] A battery compartment is installed on the top of the surface of the mounting seat, and a connecting wire harness is installed between the battery compartment and each of the electromagnets;

[0022] A ball head contact is fixed on the surface of the contact cover, and the ball head of the ball head contact is designed to be rotatable. The battery compartment is used to install the battery. When the ball head contact is contacted, the current in the battery flows into each electromagnet through the battery compartment and the connecting harness.

[0023] As a further preferred embodiment of the present technical solution, the pressure applying component includes:

[0024] An electric hydraulic rod is installed on the surface of the bearing assembly, a pressure pedal is fixed at the bottom of the electric hydraulic rod, a contact boss in contact with the contact frame is fixed at a position on the top surface of the pressure pedal away from the electric hydraulic rod, and the cross-sectional radius of one end of the contact boss gradually increases toward the lateral radius of the other end.

[0025] As a further preferred embodiment of the technical solution, a card interface is provided in the middle section of the contact frame, and a plurality of rotatable balls are installed inside the card interface, and the balls are used to contact the contact boss.

[0026] As a further preferred embodiment of the present technical solution, a loading tank opening is provided on the top of the loading frame, an asphalt filling tank is installed at the loading tank opening of the loading frame, an electric filling machine is installed in the middle section of the interior of the loading frame, and the electric filling machine and the asphalt filling tank are connected;

[0027] The threaded screw structure and the pressure assembly are both provided with two, wherein the two threaded screws are respectively arranged at positions inside the mounting frame directly opposite to the frame opening, and the pressure assemblies are respectively arranged at positions at both ends outside the mounting frame close to the frame opening;

[0028] The two threaded screw structures are driven by belts.

[0029] As a further preferred embodiment of the present technical solution, the threaded screw structure includes:

[0030] The screw rod has a transmission wheel and a contact ring fixed at both ends thereof, the transmission wheel is matched with the belt, and the surface of the transmission wheel and the surface of the contact ring are used to contact with the ball head contact point.

[0031] As a further preferred embodiment of the present technical solution, a placing bin is opened inside the pressure pedal, and a plurality of inlay openings are opened in the placing bin, a filling seat is installed in each inlay opening, the bottom of the filling seat is flush with the bottom of the pressure pedal, and a plurality of filling nozzles and pressure sensors are installed at the bottom of the filling seat.

[0032] As a further preferred embodiment of the present technical solution, the filling nozzle, the filling seat, the electric filling machine and the asphalt filling tank are sequentially connected, and the control panel is used to control the use of the electric filling machine, the filling nozzle, the pressure sensor and the electric hydraulic rod.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The asphalt pavement material fatigue testing equipment based on pressure changes applies pressure non-continuously during the test and adopts an intermittent pressurization method, which effectively avoids the over-elastic effect of the asphalt pavement caused by continuous pressure, thereby affecting the test results. In addition, through the intermittent coordination between the contact structure and the threaded screw structure, the asphalt pavement material can obtain a short recovery period after the test pressurization, which is closer to the stress state in actual use, reduces the damage to the asphalt pavement during the test to a certain extent, and reduces the service life of the asphalt pavement material consumed by the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is an isometric view of the present invention;

[0036] Figure 2 for Figure 1 Structural composition diagram after removing the asphalt filling tank;

[0037] Figure 3 It is a main cross-sectional view of the present invention;

[0038] Figure 4 Auxiliary cross-sectional view of the present invention

[0039] Figure 5 This is a bottom structural diagram of the pressure-applying assembly of the present invention;

[0040] Figure 6 This is a top structural diagram of the pressure-applying assembly of the present invention;

[0041] Figure 7 It is a structural diagram of the drive assembly of the present invention;

[0042] Figure 8It is a structural composition diagram of the mounting seat of the present invention.

[0043] In the figure: 1, asphalt filling tank; 2, control panel; 3, assembly cover; 4, carrying frame; 5, pressure assembly; 501, electric hydraulic rod; 502, pressure pedal; 503, filling seat; 504, filling nozzle; 505, pressure sensor; 506, placement bin; 507, contact boss; 6, driving assembly; 601, servo motor; 602, belt; 603, screw; 604, contact frame; 605, contact ring; 606 , shaft seat; 607, return spring; 608, limit shaft; 609, transmission wheel; 610, carrying seat; 611, retention gap; 612, contact back cover; 613, retention groove; 614, limit plate; 615, sphere; 616, card interface; 617, contact front cover; 618, ball head contact; 619, electromagnetic screw block; 620, battery compartment; 7, vehicle connector; 8, electric filling machine; 9, heat dissipation net; 10, carrying tank mouth. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Before understanding the technical solution proposed in this application, it should be clear that the fatigue test of asphalt pavement materials based on pressure changes mainly involves repeated loading and unloading of asphalt pavement materials under different pressure conditions, simulating the vehicle load in actual road use, so as to observe and record whether the material suffers fatigue damage after a certain number of load cycles. This test method can evaluate the durability, fatigue resistance and deformation characteristics of the material under different pressure environments, and simulate the impact of different road conditions and traffic flow on pavement materials by precisely controlling the size and frequency of the applied pressure, so as to more accurately evaluate its performance in actual applications.

[0046] like Figures 1 to 8 As shown, the present invention proposes a technical solution, which relates to an asphalt pavement material fatigue testing device based on pressure changes, aiming to simulate the pressure changes that the asphalt pavement material is subjected to during actual road use so as to evaluate its fatigue performance.

[0047] It should be understood that a fatigue test device for asphalt pavement materials based on pressure changes includes:

[0048] The load-bearing assembly is used to be assembled with the pressure-applying assembly 5 and a vehicle body running outside the asphalt road surface, so as to simulate actual road usage conditions.

[0049] Specifically, the bearing components include:

[0050] The carrying frame 4 has frame openings at both ends of its bottom for matching with the pressure-applying component 5. A control panel 2 is fixed to one end of the surface of the carrying frame 4. The control panel 2 is electrically connected to the driving source for controlling the operation of the entire test equipment.

[0051] The control panel 2 is specifically used to control and record the use of the electric filling machine 8 , the filling nozzle 504 , the pressure sensor 505 and the electric hydraulic rod 501 .

[0052] It should be noted that the reference Figure 2 It can be seen that a connecting seat 7 for installing an I-beam is fixed to the top of both ends of the surface of the carrying frame 4 away from the control panel 2. During the actual assembly process, one end of the I-beam and the connecting seat 7 are assembled together by punching holes and assembling screw rods and nuts, and the other end of the I-beam is connected to the forklift arm of a forklift by welding, so as to facilitate the movement or transportation of the entire carrying frame 4 and the test components thereon. It should be added that the design of the connecting seat 7 not only ensures a stable connection between the I-beam and the carrying frame 4, but also provides a standard interface for cooperating with a forklift, thereby improving the flexibility and efficiency of the test.

[0053] In addition, reference Figure 2 and Figure 3 It can be seen that in the present invention, a loading tank port 10 is opened on the top of the loading frame 4, and an asphalt filling tank 1 is installed at the loading tank port 10. The asphalt filling tank 1 is used to provide the asphalt material required for the test. An electric filling machine 8 is installed in the middle section inside the loading frame 4. The electric filling machine 8 and the asphalt filling tank 1 are connected to ensure the continuous supply of asphalt material. It should be noted that the electric filling machine 8 in this application is a filling device used for engineering materials. It is a mature technical device existing at this stage, specifically a "Shihe Group" pipe chain conveyor with a horizontal conveying distance of 60 to 80m and a vertical conveying distance of 40 to 50m.

[0054] In addition, a fatigue testing device for asphalt pavement materials based on pressure changes proposed in the present invention also includes: a pressure-applying component 5, wherein the pressure-applying component 5 is installed at the outer bottom of the load-bearing component, and is responsible for implementing a fatigue test of pressure changes on the asphalt pavement material to evaluate the performance of the material under repeated pressure.

[0055] It should be added that reference Figure 5 and Figure 6 It can be seen that the pressure-applying component 5 specifically includes:

[0056] The electric hydraulic rod 501 is installed on the surface of the bearing assembly. A pressure pedal 502 is fixed to the bottom of the electric hydraulic rod 501. A contact boss 507 in contact with the contact frame 604 is fixed to the top surface of the pressure pedal 502 away from the electric hydraulic rod 501. The cross-sectional radius of one end of the contact boss 507 gradually increases toward the lateral radius of the other end to simulate the uneven distribution of pressure in actual road use.

[0057] It should also be noted that the asphalt pavement material fatigue testing equipment based on pressure changes proposed in the present invention also includes: a driving component 6, which is embedded in the interior of the bearing component. Its main function is to push the pressure-applying component 5 to move toward the asphalt pavement material, and continuously apply pressure to the asphalt pavement material during the movement to simulate the pressure changes in actual road use.

[0058] It should be noted that the reference Figure 7 and Figure 8 It can be seen that the driving component 6 specifically includes:

[0059] The driving source, installed outside the load-bearing assembly, is responsible for providing rotational power to drive the operation of the entire test equipment.

[0060] It should be noted that, in the present invention, the driving source is a servo motor 601, referring to Figure 2 It can be seen that it is installed at one end outside the mounting frame 4.

[0061] The threaded screw structure is arranged inside the bearing component and fixed to the driving source, and is used to convert the rotational power into linear motion, thereby pushing the pressure component 5.

[0062] It should be noted that, in the present invention, the threaded screw structure specifically includes:

[0063] Screw 603, one end of screw 603 is fixed to one end of servo motor 601, and a transmission wheel 609 and a contact ring 605 are fixed to both ends of screw 603 respectively. Transmission wheel 609 and belt 602 are adapted to each other, and the surface of transmission wheel 609 and the surface of contact ring 605 are used to contact with ball head contact 618 to realize power-on control of electromagnet.

[0064] The contact structure is arranged on the periphery of the screw rod 603. The unidirectional rotation of the servo motor 601 is used to cause the contact structure to perform unidirectional linear displacement on the periphery of the threaded screw rod structure. The bottom of the contact structure contacts the top of the pressure component 5. During the unidirectional displacement of the contact structure, the pressure component 5 gradually applies pressure to the asphalt pavement material to simulate the pressure change in actual road use. In addition, it should be added that in actual use, an assembly cover 3 for accommodating one end of the screw rod 603 is fixed to the outside of the mounting frame 4. The specific assembly position of the assembly cover 3 is shown in FIG. Figure 1The assembly cover 3 and the screw rod 603 are rotationally connected.

[0065] Specifically, refer to Figure 8 It can be seen that the contact structure includes:

[0066] A carrier seat 610 is provided with a contact frame 604 fixed at the bottom thereof, which contacts the top of the pressure-applying component 5. A retention groove 613 is provided at one end of the carrier seat 610, and retention notches 611 are evenly distributed in the retention groove 613. An electromagnet is installed on the inner wall of the retention notch 611 in the retention groove 613 of the carrier seat 610, and a power supply component for driving the electromagnet is installed based on the retention groove 613 of the carrier seat 610. An electromagnetic screw block 619 is installed at the retention notch 611 of the carrier seat 610, and the electromagnetic screw block 619 is adapted to the periphery of the threaded screw structure, and contact covers for shielding the retention groove 613 and controlling the connection and disconnection of the power supply component are installed on both sides of one end of the surface of the carrier seat 610.

[0067] Specifically, refer to Figure 7 and Figure 8 It can be seen that the contact covers are respectively the contact rear cover 612 and the contact front cover 617 based on their positions, wherein the contact front cover 617 contacts the surface of the contact ring 605 , and the contact rear cover 612 contacts the surface of the transmission wheel 609 .

[0068] It should be noted that, in order to limit the movement of the electromagnetic screw block 619, refer to Figure 8 It can be seen that limiting plates 614 are fixed at both ends of the retention notch 611 in the retention groove 613 of the mounting seat 610, wherein the limiting plates 614 are used to limit the moving range of the electromagnetic screw block 619 to prevent the electromagnetic screw block 619 from escaping from the retention groove 613 during movement, thereby improving the stability of the electromagnetic screw block 619 during movement.

[0069] refer to Figure 2 and Figure 7 It can be known that in the present invention, a limiting shaft 608 is arranged at a position near the threaded screw structure inside the mounting frame 4, and the two ends of the outside of the limiting shaft 608 are respectively fixed with shaft seats 606 fixed to the inner wall of the bearing component, and the other end of the inside of the mounting seat 610 is sleeved outside the limiting shaft 608 and is movably connected to the limiting shaft 608. A return spring 607 is installed between the mounting seat 610 and one of the shaft seats 606. The return spring 607 is used to return the mounting seat 610 to the initial position of the unidirectional linear displacement when the power supply component is disconnected, and to reconnect the power supply component so that the contact structure performs unidirectional linear displacement again.

[0070] It should be noted that, under the action of the return spring 607, the mounting seat 610 can ensure that it can automatically return to the initial position after each test, which not only improves the continuity and efficiency of the test, but also ensures the consistency and accuracy of the test data. In addition, the design of the return spring 607 also enhances the stability of the mounting seat 610 during movement, avoiding test errors caused by vibration or external force interference.

[0071] In order to further optimize the performance of the testing equipment, the present invention further provides a buffer pad (not shown in the figure) between the mounting seat 610 and the contact frame 604. The buffer pad is made of a highly elastic material and can play a buffering role when the mounting seat 610 contacts the contact frame 604, thereby reducing the noise and wear caused by hard contact, thereby extending the service life of the equipment.

[0072] In summary, the present invention achieves precise control and regulation of pressure changes during fatigue testing of asphalt pavement materials through a carefully designed mounting seat 610 and its related components, improves the accuracy and reliability of the test, and provides strong technical support for the research and application of pavement materials.

[0073] It should be added that the initial position reference mentioned in the present invention is Figure 7 It can be seen that this is the position when the mounting base 610 is close to the servo motor 601.

[0074] It should be further explained that, in the present invention, the power supply component specifically includes:

[0075] The battery compartment 620 is installed on the top of the surface of the mounting base 610, and a connecting wire harness is installed between the battery compartment 620 and each electromagnet.

[0076] In addition, a ball head contact 618 is fixed to the surface of the contact cover, and the ball head of the ball head contact 618 is designed to be rotatable. It should be noted that the battery compartment 620 is used to install the battery. When the ball head contact 618 is touched, the current in the battery flows into each electromagnet through the battery compartment 620 and the connecting wiring harness, thereby activating the electromagnet and generating magnetism.

[0077] In addition, in order to reduce the friction between the contact frame 604 and the contact boss 507, refer to Figure 4 and Figure 8 It can be seen that in the present invention, a card interface 616 is provided in the middle section of the contact frame 604, and a plurality of rotatable balls 615 are installed inside the card interface 616. The balls 615 are used to contact the contact boss 507 to ensure uniform pressure.

[0078] It should be noted that the surface of the sphere 615 is made of wear-resistant material to increase service life and reduce wear. At the same time, the rotation design of the sphere 615 can effectively disperse the friction between the contact frame 604 and the contact boss 507, making the entire test process smoother and further improving the accuracy and reliability of the test.

[0079] It should also be added that reference Figure 3 and Figure 7 It can be seen that the two threaded screw structures are transmitted with the help of belt 602 to achieve synchronous movement. It should be noted that there are two threaded screw structures and two pressure-applying components 5, and the two threaded screws are respectively arranged at positions inside the mounting frame 4 opposite to the frame opening, and the pressure-applying components 5 are respectively arranged at both ends of the outside of the mounting frame 4 close to the frame opening to ensure the symmetry and stability of the test equipment.

[0080] It should be particularly pointed out that in the process of testing asphalt pavement materials, in order to minimize damage to the materials, the present invention proposes a design.

[0081] Specifically, a placement bin 506 is designed inside the pressure pedal 502. At the position of this placement bin 506, a number of inlay openings are precisely cut out of the pressure pedal 502. The size and shape of these inlay openings are designed to adapt to a specific filling seat 503. Each filling seat 503 is precisely installed in the corresponding inlay opening to ensure that its bottom is completely flush with the bottom of the pressure pedal 502, which not only ensures the stability of the structure but also helps to achieve uniform filling of the asphalt material. In addition, a number of filling nozzles 504 and pressure sensors 505 are installed at the bottom of each filling seat 503. These filling nozzles 504 are responsible for evenly spraying the asphalt material onto the pressure pedal 502, while the pressure sensor 505 monitors the applied pressure in real time to ensure that the pressure distribution during the entire test process is uniform and meets the predetermined standards.

[0082] In the implementation of the present invention, in order to further improve the efficiency and accuracy of the testing process, the filling nozzle 504, the filling seat 503, the electric filling machine 8 and the asphalt filling tank 1 are designed to be connected in sequence, so that the asphalt material can flow smoothly from the asphalt filling tank 1 to the filling nozzle 504, thereby realizing a continuous filling process. In addition, the control panel 2 is electrically connected to the electric filling machine 8, the filling nozzle 504, the pressure sensor 505 and the electric hydraulic rod 501, so that the entire testing process can be centrally controlled through the control panel 2, thereby realizing the automation of the entire testing process.

[0083] In addition, in order to extend the service life of the electric filling machine 8 , a heat dissipation net 9 for dissipating heat from the electric filling machine 8 is installed in the middle of one side of the mounting frame 4 of the present invention.

[0084] Finally, when the device is actually used, the asphalt material is first filled into the asphalt filling tank 1, and then the electric filling machine 8 is started. The electric filling machine 8 conveys the asphalt material to the filling nozzle 504, and the asphalt material is evenly sprayed into the filling seat 503 on the pressure pedal 502 through the filling nozzle 504 to ensure that the asphalt material is evenly distributed. Then, the servo motor 601 is started through the control panel 2, and the servo motor 601 drives the threaded screw structure to rotate, thereby pushing the mounting seat 610 and the contact structure thereon to perform unidirectional linear displacement, and the bottom of the contact structure contacts the top of the pressure component 5, pushing the pressure component 5 to apply pressure to the asphalt pavement material. During this process, the pressure sensor 505 monitors the applied pressure in real time and feeds back the data to the control panel 2. The control panel 2 is used to precisely control the test process and allow the filling nozzle 504 to compensate for the damaged asphalt pavement material. With the unidirectional linear displacement of the mounting seat 610, the pressure component 5 gradually applies pressure to the asphalt pavement material to simulate the pressure changes in actual road use. When the mounting seat 610 moves to the other end of the limit shaft 608, the return spring 607 begins to work and pulls the mounting seat 610 back to the initial position. At the same time, the power supply component is disconnected, and the electromagnetic screw block 619 returns to the initial position under the action of the return spring 607, waiting for the next test. By repeating the above steps, multiple pressure cycle tests can be performed on the asphalt pavement material to observe and record whether the material has fatigue damage after a certain number of load cycles.

[0085] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is limited by the attached embodiments and their equivalents.

Claims

1. A fatigue testing device for asphalt pavement materials based on pressure changes, characterized in that: include: A load-bearing assembly, used for assembly with a pressure-applying assembly (5) and a vehicle body running outside an asphalt road surface; A pressure-applying assembly (5) is mounted on the outer bottom of the bearing assembly and is used to perform a fatigue test of pressure variation on the asphalt pavement material; A driving component (6) is embedded in the interior of the bearing component and is used to push the pressure component (5) to move toward the asphalt pavement material, and to allow the pressure component (5) to continuously apply pressure to the asphalt pavement material during the movement; The bearing assembly comprises: A carrying frame (4), wherein both ends of the bottom of the carrying frame (4) are respectively provided with frame openings for matching with the pressure-applying component (5), and a control panel (2) is fixed to one end of the surface of the carrying frame (4); The driving component (6) comprises: A driving source, installed outside the bearing assembly, for providing rotational power, the driving source being electrically connected to a control panel (2); A threaded screw structure is arranged inside the bearing assembly and fixed to the driving source; The contact structure is arranged on the periphery of the threaded screw structure, and the contact structure is caused to perform unidirectional linear displacement on the periphery of the threaded screw structure by utilizing the unidirectional rotation of the driving source, the bottom of the contact structure is in contact with the top of the pressure component (5), and the pressure component (5) gradually applies pressure to the asphalt pavement material during the unidirectional displacement of the contact structure; The contact structure comprises: A carrier (610), wherein a contact frame (604) in contact with the top of the pressure-applying component (5) is fixed at the bottom of the carrier (610), a retention groove (613) is provided at one end of the carrier (610), and the carrier (610) is provided with uniformly distributed retention notches (611) in the retention groove (613), and an electromagnet is installed on the inner wall of the retention notch (611) in the retention groove (613) of the carrier (610), and a power supply component for driving the electromagnet to operate is installed on the carrier (610 based on the retention groove (613), and an electromagnetic screw block (619) is installed at the retention notch (611) of the carrier (610) and moves based on the operation of the power supply component, and the electromagnetic screw block (619) is adapted to the periphery of the threaded screw structure, and contact covers for shielding the retention groove (613) and controlling the connection and disconnection of the power supply component are installed on both sides of one end of the surface of the carrier (610); A limit shaft (608) is arranged inside the bearing component near the threaded screw structure, and shaft seats (606) fixed to the inner wall of the bearing component are respectively fixed at two ends of the outside of the limit shaft (608), and the other end of the inside of the carrying seat (610) is sleeved outside the limit shaft (608) and is movably connected to the limit shaft (608). A return spring (607) is installed between the carrying seat (610) and one of the shaft seats (606). The return spring (607) is used to return the carrying seat (610) to the initial position of the unidirectional linear displacement when the power supply component is disconnected, and to reconnect the power supply component so that the contact structure performs unidirectional linear displacement again.

2. The asphalt pavement material fatigue testing equipment based on pressure change according to claim 1 is characterized by: The power supply component comprises: A battery compartment (620) is installed at the top of the surface of the mounting seat (610), and a connecting wire harness is installed between the battery compartment (620) and each of the electromagnets; A ball head contact (618) is fixed on the surface of the contact cover, and the ball head of the ball head contact (618) is designed to be rotatable. The battery compartment (620) is used to install the battery, and the current in the battery flows into the ball head contact (618) through the battery compartment (620).

3. The asphalt pavement material fatigue testing equipment based on pressure change according to claim 1 is characterized by: The pressure applying component (5) comprises: An electric hydraulic rod (501) is mounted on the surface of the bearing assembly, a pressure pedal (502) is fixed at the bottom of the electric hydraulic rod (501), a contact boss (507) in contact with the contact frame (604) is fixed at a position of the top surface of the pressure pedal (502) away from the electric hydraulic rod (501), and the cross-sectional radius of one end of the contact boss (507) gradually increases toward the lateral radius of the other end.

4. The asphalt pavement material fatigue testing device based on pressure change according to claim 3 is characterized in that: A card interface (616) is provided in the middle section of the contact frame (604), and a plurality of rotatable balls (615) are installed inside the card interface (616). The balls (615) are used to contact the contact boss (507).

5. The asphalt pavement material fatigue testing equipment based on pressure change according to claim 2, characterized in that: The top of the carrying frame (4) is provided with a carrying tank opening (10), an asphalt filling tank (1) is installed at the carrying tank opening (10) of the carrying frame (4), an electric filling machine (8) is installed in the middle section of the carrying frame (4), and the electric filling machine (8) and the asphalt filling tank (1) are connected; The threaded screw structure and the pressure assembly (5) are both provided with two, wherein the two threaded screws are respectively arranged at positions inside the mounting frame (4) directly opposite to the frame opening, and the pressure assembly (5) is respectively arranged at positions at both ends outside the mounting frame (4) close to the frame opening; The two threaded screw structures are driven by a belt (602).

6. The asphalt pavement material fatigue testing equipment based on pressure change according to claim 5, characterized in that: The threaded screw structure comprises: A screw rod (603) is provided with a transmission wheel (609) and a contact ring (605) fixed at both ends of the screw rod (603), the transmission wheel (609) is adapted to the belt (602), and the surface of the transmission wheel (609) and the surface of the contact ring (605) are used to contact the ball head contact (618).

7. The asphalt pavement material fatigue testing equipment based on pressure change according to claim 3 is characterized by: The pressure pedal (502) has a placement chamber (506) formed inside thereof. The pressure pedal (502) has a plurality of inlay openings formed at the placement chamber (506). A filling seat (503) is installed in each inlay opening. The bottom of the filling seat (503) is flush with the bottom of the pressure pedal (502), and a plurality of filling nozzles (504) and a pressure sensor (505) are installed at the bottom of the filling seat (503).

8. The asphalt pavement material fatigue testing equipment based on pressure change according to claim 7 is characterized by: The filling nozzle (504), the filling seat (503), the electric filling machine (8) and the asphalt filling tank (1) are sequentially connected, and the control panel (2) is used to control the use of the electric filling machine (8), the filling nozzle (504), the pressure sensor (505) and the electric hydraulic rod (501).

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