Device and method for testing skid resistance and wear resistance of skid-resistant surface layer mixture

Abstract

The invention belongs to the technical field of road engineering test and inspection, and particularly relates to a device and a method for testing skid resistance and wear resistance of a skid-resistant surface layer mixture. The test device comprises a main body frame, a wheel set system, a counterweight system, a wheel set rotating system, a wheel set lifting system, an abrasion test piece, an environment simulation system and a control system, wherein the wheel set system comprises a fixed disc and a test wheel rotationally connected to the fixed disc; the counterweight system is arranged above the fixed disc; the wheel set rotating system comprises a rotating motor and a rotating shaft; the rotating shaft extends into the main body frame and is in clearance fit with the fixed disc; the wheel set lifting system comprises a lever lifting assembly, the lever lifting assembly comprises a lifting rod, one end of the lifting rod is detachably connected with the fixing disc, and the other end of the lifting rod extends out of the main body frame and is rotationally and detachably connected with the lever; and the abrasion test piece is arranged on the main body frame below the wheel set system. The performance testing device provided by the invention can more truly simulate the actual abrasion condition of the anti-skid surface layer mixture of the vehicle.

Description

Technical Field

[0001] The present invention belongs to the technical field of road engineering test and inspection, and particularly relates to a test device and method for the anti-slip and wear-resistant performance of an anti-slip surface mixture. Background Technique

[0002] As of the end of 2023, the total mileage of highways opened to traffic in China has reached 5.6 million kilometers, and the vast majority of them adopt asphalt pavement structures. Although the current asphalt pavement structure, material design technology, construction technology, and operation management level have developed greatly, the technical research on the anti-slip performance of asphalt pavements has not received enough attention.

[0003] With the progress of society and the continuous development of people's travel needs, the service performance of roads not only requires structural durability, but also puts forward higher requirements for driving comfort and driving safety, especially the anti-slip performance of the road surface. The anti-slip performance of many expressway asphalt pavements drops rapidly after they are opened to traffic. In the acceptance inspection two to three years after opening to traffic, the anti-slip performance index - the lateral force coefficient often fails to meet the minimum requirements of relevant specifications. After the expressway is officially opened to traffic, especially under the modern traffic conditions of high speed, heavy load, large traffic volume, and frequent extreme weather, the anti-slip performance of highway asphalt pavements gradually exposes the problem of excessive attenuation, which affects driving safety.

[0004] At present, there is a disconnection problem in the evaluation and test of the anti-slip and durable performance of the anti-slip surface layer of asphalt pavements. As is well known, the paving of the anti-slip surface layer of asphalt pavements has to go through stages such as the target mix design of the mixture, the production mix design, the verification of the production mix, large-area on-site paving, and acceptance inspection. However, at present, there are no control requirements for the anti-slip and wear-resistant performance indicators in the target mix design, production mix design, and verification of the production mix of the mixture. When paving on a large area on-site, only two indicators, namely the texture depth and the pendulum value, are used to roughly detect the anti-slip and wear-resistant performance, while in the acceptance inspection stage, indicators such as the lateral force coefficient, dynamic friction coefficient, texture depth, and pendulum value specified in the "Code for Field Tests of Highway Subgrade and Pavement" (JTG 3450-2019) are used to evaluate whether the anti-slip and wear-resistant performance of the anti-slip surface layer meets the acceptance inspection standards. If the anti-slip and wear-resistant performance of the mixture can be accurately evaluated before construction, it is beneficial to ensure the smooth progress of the subsequent acceptance inspection work.

[0005] The invention patent with the publication number CN113820269A discloses a rapid tester for road surface functions. This tester can simulate the braking situation of a vehicle, measure the braking distance and braking time, and detect the wear degree of the road surface and the durability of the road surface material. The invention applies pressure to the specimen through a hydraulic device to simulate the load of a vehicle on an asphalt road surface. When there are unevennesses in the specimen or particles fall off during the abrasion process, this pressure application method will cause the test wheel to bounce at the unevennesses or particle - falling positions of the specimen, thus affecting the abrasion effect.

[0006] The utility model patent with the publication number CN204269495U discloses an indoor test device for accelerating the abrasion of road surface materials. The transmission shaft of this test device includes a vertical rod and a horizontal rod. The power output end of the engine is connected to a transmission device arranged on the vertical rod of the transmission shaft through a power control device to drive a solid rubber tire to rotate. A variable load piece is arranged on the horizontal rod of the transmission shaft to provide a load on the specimen. When it is necessary to lift the solid rubber tire, the power output end of the hydraulic pump is connected to the vertical rod of the transmission shaft through a cross - connecting hinge. This new type uses a variable load piece to replace the hydraulic device to provide the load, which well solves the problem that the test wheel bounces at the unevennesses or particle - falling positions of the specimen. However, the way of setting the variable load piece in this new type introduces new technical problems: (1) This new type sets the variable load piece on the transmission shaft, which has extremely high requirements for the dynamic balance of the transmission shaft, and the additional mass of the variable load piece will change the mass center distribution, easily causing resonance due to imbalance, affecting the test accuracy (such as the fluctuation of sensor data) and the mechanical life. (2) This new type uses a hydraulic pump and a cross - connecting hinge to lift the transmission shaft and the variable load piece on the transmission shaft. On the one hand, during the lifting process, eccentric, inclined or jamming phenomena are likely to occur, affecting the installation of the specimen, the stability of the transmission system and the smoothness of the abrasion process, and further affecting the accuracy of the simulation result. On the other hand, during the lifting process, the cross - connecting hinge may accidentally fall off or the hinge fails, especially in the case of improper operation or severe wear, which may cause damage to the test device and even pose a safety threat to the operator.

[0007] Therefore, designing an indoor experimental device that can truly simulate the abrasion of a vehicle on an asphalt road surface to accurately evaluate the anti - skid and wear - resistant performance of the mixture has become a technical problem to be urgently solved. Summary of the Invention

[0008] Aiming at the above technical problems, the present invention aims to provide an anti-slip and wear-resistant performance testing device and testing method for anti-slip surface mixture, which can accurately control test elements such as test load, environmental temperature, abrasion water, abrasion medium, etc., simulate the attenuation law and decay model of the anti-slip and wear-resistant performance of the anti-slip surface under the coupling action of multiple factors, realize the effective testing and evaluation of the anti-slip and wear-resistant indexes of the anti-slip surface asphalt mixture in the stages of target mix design, production mix design, production mix verification, and large-area on-site paving, realize the effective connection with the handover and acceptance, and solve the engineering problem that the anti-slip performance of the anti-slip surface is insufficient in the current handover and acceptance but the reason cannot be traced. The technical solution adopted by the present invention is as follows:

[0009] An anti-slip and wear-resistant performance testing device for anti-slip surface mixture, comprising a main frame, a wheel set system, a counterweight system, a wheel set rotation system, a wheel set lifting system, a wear test piece, an environment simulation system and a control system,

[0010] The main frame is a high-strength main frame. The wheel set system is located inside the main frame. The wheel set system includes a fixed disk and a test wheel rotatably connected to the fixed disk. The counterweight system is arranged above the fixed disk. The wheel set rotation system includes a rotation motor and a rotation shaft. The rotation motor is arranged above the main frame. The rotation shaft extends into the main frame and is in clearance fit with the fixed disk. The wheel set rotation system and the wheel set system are not connected. The rotation shaft can be a square shaft. The rotation motor drives the fixed disk to rotate through the rotation shaft. The test wheel arranged on the fixed disk rotates with the rotation of the fixed disk. The rotation motor only provides power for the rotational movement of the wheel set system and does not provide vertical movement power for the wheel set system;

[0011] The wheel set lifting system includes two lever lifting components symmetrically arranged on the fixed disk. The lever lifting component includes a support, a lever and a lifting rod. The support is arranged above the main frame. The lever is rotatably connected to the support. One end of the lifting rod is detachably connected to the fixed disk, and the other end extends out of the main frame and is rotatably and detachably connected to the lever. By pressing the end of the lever far from the lifting rod, the fixed disk and the counterweight system on the fixed disk can be lifted by using the lever principle through the lifting rod. Both ends of the lifting rod are detachably connected to the fixed disk and the lever, which is convenient for removing the lifting rod during the abrasion process;

[0012] The wear test piece is arranged on the main frame below the wheel set system. In the wear state, the test wheel contacts the wear test piece, and the load pressure applied by the test wheel on the wear test piece is adjusted through the counterweight system;

[0013] The control system can be a programmable logic control system. The control system is arranged above the main frame. The control system is signal-connected to the environment simulation system and the wheel set rotation system.

[0014] Further, there are three test wheels, and there are three fixed seats below the fixed disk. The test wheels are rotatably connected to the fixed seats. The vertical distances from the centers of the three test wheels to the axis of the fixed disk are the same, so as to ensure that the circular trajectories formed by the rotation of the three test wheels coincide. The test tire can be a directional wheel or a universal wheel according to different test requirements.

[0015] Further, the counterweight system includes a number of counterweight disks. Counterweight disk fixing holes and lifting rod through holes are provided at the same positions on the number of counterweight disks and the fixed disk. The counterweight disks can be fixed on the fixed disk through the counterweight disk fixing holes. For example, threads are provided in the counterweight disk fixing holes, and bolts can be used to connect the counterweight disks to each other and fix the counterweight disks on the fixed disk. A long strip-shaped notch is provided on the counterweight disk. The rotating shaft vertically passes through the long strip-shaped notch and extends below the fixed disk. The rotating shaft does not contact the counterweight disk. The wheel set lifting system further includes a lifting rod connecting member. The lifting rod passes through the lifting rod through hole and is connected to the lifting rod connecting member. The lifting rod connecting member can be a nut, and threads adapted thereto are provided on the lifting rod.

[0016] Further, the counterweight system further includes a number of small counterweight blocks. Counterweight block connecting members are provided on the small counterweight blocks. The counterweight block connecting members are adapted to the counterweight disk fixing holes. For example, threads adapted to the counterweight disk fixing holes are provided on the counterweight block connecting members, and the small counterweight blocks can be directly connected to the counterweight disks. The weight of the counterweight disk is relatively heavy, and the weight of the small counterweight block is relatively light. By adopting the cooperation of the counterweight disk and the small counterweight block, the accurate adjustment of the counterweight is facilitated.

[0017] Further, the environment simulation system includes a temperature control system, a wear water spraying system, a wear medium spraying system, and an ultraviolet irradiation aging system.

[0018] The temperature control system includes a temperature sensor and a temperature controller. The temperature value in the main body frame is controlled by the control system. The temperature sensor is arranged in the main body frame and is used to detect the temperature in the main body frame. The temperature controller is arranged above the main body frame and is communicated with the main body frame through an air supply port. The test temperature is adjusted by blowing hot and cold air into the main body frame.

[0019] The wear water spraying system includes a water pump, a water tank, a water pipe, and a nozzle. The water spraying amount is set by the control system. The water pump and the water tank are arranged above the main body frame. The nozzle is arranged in the main body frame. The nozzle is connected to the water tank through the water pipe. The nozzle is used to uniformly spray misty water on the contact area between the test wheel and the wear specimen.

[0020] The abrasion medium spraying system includes a sand box and a sand spraying pipe. The sand spraying amount is set by a control system. The sand spraying pipe is connected to the sand box. The sand box is arranged above the main frame, and the sand spraying pipe is arranged inside the main frame for uniformly spraying abrasion medium onto the contact area between the test wheel and the abrasion specimen. The abrasion medium can be emery, quartz sand or particulate matter collected by sweeping the road surface;

[0021] The ultraviolet irradiation aging system includes an ultraviolet lamp. The test road surface is irradiated by the ultraviolet lamp to accelerate its aging. The irradiation time of the ultraviolet lamp is controlled by the control system. The ultraviolet lamp is arranged below the fixed disk.

[0022] Furthermore, the main frame is made of stainless steel, and four lifting rings are arranged at the top of the main frame; heat preservation cotton is arranged inside the main frame, and observation ports are arranged around the main frame. Heat preservation glass is arranged on the observation ports. For the convenience of the test, a door is arranged at the front and back of the main frame respectively. A plurality of stainless steel cross beams are arranged in the middle of the main frame. A waste liquid flowing gap is arranged between the stainless steel cross beams. A first limiting block is arranged on the stainless steel cross beam. The abrasion specimen tray is detachably connected to the stainless steel cross beam. The first limiting block is used to limit the abrasion specimen tray to ensure that the abrasion specimen tray is in the same position in each test. A second limiting block is arranged on the abrasion specimen tray. The abrasion specimen forming tray is placed on the abrasion specimen tray. The abrasion specimen forming tray is arranged at the center of the abrasion tray and is not connected to each other. The second limiting block is used to limit the abrasion specimen forming tray to ensure that the abrasion specimen forming tray is in the same position in each test, and the center of the abrasion specimen forming tray coincides with the vertical projection of the center of the tire rotation track of the test wheel. The abrasion specimen is arranged in the abrasion specimen forming tray;

[0023] A waste liquid collection box is also arranged on the main frame. The waste liquid collection box is arranged below the stainless steel cross beam. A liquid level observation port and a drain port are arranged on the waste liquid collection box. Anticorrosive glass is arranged on the liquid level observation port. Drain holes are arranged on the abrasion specimen tray to facilitate the waste liquid to flow into the waste liquid collection box during the test. The drain port is used to discharge the waste liquid collected and precipitated inside the waste liquid collection box irregularly. When the waste liquid in the waste liquid collection box precipitates and cakes, it can be manually stirred to make the particles float up to form a suspension for the waste liquid to be discharged from the drain port.

[0024] Furthermore, the wear resistance testing device also includes a test auxiliary support. The test auxiliary support is welded by high-strength stainless steel, and four legs are arranged at the bottom. Universal wheels are installed on the four legs. The test auxiliary support is not connected to the high-strength main frame and can move freely. When the abrasion specimen needs to be detected after the completion of the stage test, the abrasion specimen tray together with the abrasion specimen forming tray is pulled out and placed on the test auxiliary support for subsequent wear resistance testing.

[0025] The present invention also discloses a test method for the anti-slip and wear-resistant performance of an anti-slip surface mixture, which is tested by using any one of the above-mentioned anti-slip and wear-resistant performance test devices, and includes the following steps:

[0026] S1. Adjust the pressure exerted by the test wheel on the wear specimen through the counterweight system;

[0027] S2. Forming the wear specimen: Mix the asphalt mixture by using a test asphalt mixture mixer, spread the mixed asphalt mixture evenly in the wear specimen forming tray, and compact it by using a small press to obtain a formed wear specimen. Test the initial dynamic rotational friction coefficient, initial pendulum value, and initial texture depth of the wear specimen, and the test method refers to the regulations in the "Field Test Regulations for Highway Subgrade and Pavement" (JTG 3450-2019).

[0028] By using a test asphalt mixture mixer to mix the asphalt mixture and a small press to compact the asphalt mixture, the prepared wear specimen can be closer to the actual asphalt pavement, which is conducive to accurately evaluating the anti-slip and wear-resistant performance of the mixture.

[0029] S3. Use the wheel pair lifting system to lift the wheel pair system, and place the wear specimen on the main frame below the wheel pair system;

[0030] S4. Control the environmental conditions in the main frame through the control system and the environmental simulation system to simulate the real pavement environment. Specifically, control the environmental temperature in the main frame, the water spraying amount of the wear water spraying system, the sand spraying amount of the wear medium spraying system, and the ultraviolet lamp irradiation time through the control system;

[0031] S5. Set the test time through the control system, set the rotation speed of the test wheel around the central axis of the fixed disk through the control system and the wheel pair rotation system, remove the lifting rod, and start the test after the temperature in the main frame is stable;

[0032] S6. After the test is completed, take out the wear specimen and test the dynamic rotational friction coefficient, pendulum value, and texture depth of the wear specimen again. The anti-slip and wear-resistant performance of the anti-slip surface mixture of the present invention is characterized by the dynamic rotational friction coefficient, pendulum value, and texture depth.

[0033] If multiple tests are required, repeat S3-S6 until the test is completed.

[0034] Further, step S1 is specifically:

[0035] S11. Calibrate the pressure values exerted by the test wheel on the wear specimen under different counterweights, draw a counterweight calibration curve, and calculate the required counterweight for the test based on the required pressure value during the test and the counterweight calibration curve;

[0036] S12. Adjust the counterweight value of the counterweight system above the fixed disk based on the counterweight required for the test calculated in step S11.

[0037] Further, step S11 is specifically as follows:

[0038] A1. Use the wheel set lifting system to lift the wheel set system to the highest point and fix it, and install the wear specimen tray into the test device.

[0039] A2. Place a flat scale into the wear specimen tray, place a grid paper with copying function on the surface of the flat scale, release the fixation of the wheel set lifting system, and place the test wheel on the grid paper.

[0040] A3. Increase the counterweight of the counterweight system and read the weight reading W1 of the flat scale.

[0041] A4. Use the wheel set lifting system to lift the test wheel to the highest point and fix it, take out the grid paper, read and calculate the contact area M1 of the three test wheels on the grid paper, and calculate the pressure P1 exerted by the wheel set system on the wear specimen under the counterweight W1, where P1 = W1 / M1.

[0042] A5. Repeat steps A1 to A4 to respectively read the weight readings W2, W3, W4, W5 of the flat scale and the contact areas M2, M3, M4, M5 on the grid paper, and respectively calculate the pressures P2, P3, P4, P5 exerted by the test wheel on the wear specimen under different counterweights.

[0043] A6. Taking the set weight reading W of the flat scale as the x-axis and the pressure P exerted by the wheel set system on the wear specimen under this counterweight as the y-axis, draw the counterweight calibration curve.

[0044] Compared with the prior art, the beneficial effects of the present invention are:

[0045] The anti-slip and wear-resistant performance testing device for the anti-slip surface mixture of the present invention controls the vertical load pressure of the wheel pair system on the wear specimen through the counterweight system. During the wear process, the wheel pair system will closely adhere to the wear specimen under the pressure of the counterweight system, and there will be no bouncing phenomenon even at uneven or chipped areas of the wear specimen. The counterweight system of the present invention is arranged on a fixed disk with a clearance fit with the rotating shaft. The setting of the counterweight system does not affect the transmission of the rotating shaft, avoiding the influence on the balance of the transmission caused by setting the counterweight on the transmission shaft and the generation of resonance during transmission, ensuring the test accuracy and mechanical life. At the same time, since the counterweight system of the present invention is arranged on the fixed disk, when replacing the wear specimen of the present invention, the fixed disk can be directly lifted. And because the fixed disk does not contact the rotating shaft, the lifting process of the present invention will not have a negative impact on the transmission shaft and will not affect the smoothness of the wear process. In summary, the anti-slip and wear-resistant performance testing device for the anti-slip surface mixture of the present invention can more realistically simulate the actual wear situation of the vehicle on the anti-slip surface mixture, and the safety and accuracy of the entire testing device are higher.

[0046] The anti-slip and wear-resistant performance testing device for the anti-slip surface mixture of the present invention can accurately test the law of road surface function attenuation of the wear specimen to be tested under the coupling action of load and environment by precisely controlling the test temperature, the pressure exerted by the wheel pair on the specimen, the rotational speed of the wheel pair, the water spraying amount, the sand scattering amount, and the specimen aging rate, and can simulate the road surface function attenuation situation of an actual road serving for several years or even more than ten years within a test time of several hours. Brief Description of the Drawings

[0047] Figure 1 It is a schematic diagram of the overall structure of the anti-slip and wear-resistant performance testing device for the anti-slip surface mixture in Embodiment 1 of the present invention;

[0048] Figure 2 It is a schematic diagram of the internal structure of the main frame in Embodiment 1 of the present invention.

[0049] Among them, 1 - main frame, 2 - wear specimen, 3 - control system, 4 - fixed disk, 5 - test wheel, 6 - rotating motor, 7 - rotating shaft, 8 - support, 9 - lever, 10 - lifting rod, 11 - fixed seat, 12 - counterweight disk, 13 - counterweight disk fixing hole, 14 - lifting rod through hole, 15 - small counterweight block, 16 - temperature controller, 17 - water tank, 18 - sand box, 19 - observation port, 20 - wear specimen forming disk, 21 - waste liquid collection box, 22 - test auxiliary support. Detailed Embodiment

[0050] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings.

[0051] For the elaboration of the required spatial relationship, three orthogonal directions of "front and back", "left and right", and "up and down (or vertical)" can be defined, and a rectangular coordinate system in space can be defined through the relative position relationship.

[0052] Embodiment 1

[0053] As Figures 1-2 shown, this embodiment discloses a test device for the anti-slip and wear-resistant performance of an anti-slip surface mixture, including a main frame 1, a wheel set system, a counterweight system, a wheel set rotation system, a wheel set lifting system, a wear test piece 2, an environment simulation system, a control system 3, and a test auxiliary bracket 22.

[0054] The wheel set system is located inside the main frame 1. The wheel set system includes a fixed disk 4 and test wheels 5 rotatably connected to the fixed disk 4. There are three test wheels 5. Three fixed seats 11 are provided below the fixed disk 4. The test wheels 5 are rotatably connected to the fixed seats 11 through bolts. All three test wheels are made of high-quality rubber pneumatic wheels with wear resistance, impact resistance, high load-bearing capacity, and shock absorption. In this embodiment, the specifications of the test wheels are: bottom plate size 100×144mm, bottom plate hole pitch 75×120mm, wheel diameter 200mm, wheel width 63mm, and net weight 3Kg. The vertical distances from the centers of the three test wheels 5 to the central axis of the fixed disk 4 are the same to ensure that the three circular trajectories formed by the rotation of the three test wheels coincide. In this embodiment, the diameters of the three circular trajectories formed by the rotation of the three test wheels are 320mm.

[0055] The counterweight system is arranged above the fixed disk 4. The counterweight system includes a number of counterweight disks 12. Counterweight disk fixing holes 13 and lifting rod through holes 14 are provided at the same positions on the number of counterweight disks 12 and the fixed disk 4. Threads are provided in the counterweight disk fixing holes 13. By screwing bolts into the counterweight disk fixing holes 13, the bottommost counterweight disk 12 can be fixed to the fixed disk 4, and then, using the same method, the next counterweight disk 12 can be fixed to the previous counterweight disk 12 to achieve the connection and fixation of the counterweight system. Long strip-shaped notches are also provided on the counterweight disks 12 to facilitate accommodating the rotating shaft 7 and the installation of the counterweight disks 12. The counterweight system also includes a number of small counterweight blocks 15. Counterweight block connectors are provided on the small counterweight blocks 15, and the counterweight block connectors are adapted to the counterweight disk fixing holes 13. In this embodiment, the counterweight block connectors are bolts, and the counterweight block connectors can be directly screwed into the counterweight disk fixing holes 13 at the top of the counterweight system to achieve the connection of the small counterweight blocks 15. Preferably, threaded holes can also be provided on the small counterweight blocks 15 to connect other counterweights.

[0056] The wheel set rotation system includes a rotation motor 6 and a rotation shaft 7. The rotation motor 6 is arranged above the main body frame 1. The rotation shaft 7 extends into the main body frame 1, vertically passes through the long strip-shaped notch on the counterweight disk 12, and then extends to a position 10 cm below the fixed disk 4. The rotation shaft 7 is in clearance fit with the fixed disk 4. After the counterweight system is fixed, the rotation shaft 7 does not contact the counterweight disk 12.

[0057] The wheel set lifting system includes two lever lifting components symmetrically arranged on the fixed disk 4. The lever lifting component includes a support 8, a lever 9, and a lifting rod 10. The support 8, the lever 9, and the lifting rod 10 are all made of stainless steel. The support 8 is arranged above the main body frame 1. The lever 9 is rotatably connected to the support 8. In this embodiment, the support 8 is welded above the main body frame 1, and the lever 9 is connected to the support 8 by bolts. The lever 9 can rotate freely around the support 8. One end of the lifting rod 10 passes through the counterweight disk 12 and the fixed disk 4 through the lifting rod through hole 14 and is connected to the lifting rod connecting piece. In this embodiment, the lifting rod connecting piece is a nut. The lifting rod 10 is provided with threads, and the two are threadedly connected. The other end of the lifting rod 10 extends out of the main body frame 1 and is rotatably and detachably connected to the end of the lever 9 by bolts. During the wear test process, when the rotation motor 6 drives the wheel set system to rotate, the lifting rod 10 needs to be disassembled.

[0058] Observation ports 19 are provided around the main body frame. Heat-insulating glass is provided on the observation ports 19. Heat-insulating cotton is provided inside the main body frame 1. A door is provided at the front and back of the main body frame 1 respectively. A plurality of stainless steel cross beams (not shown in the figure) are provided in the middle of the main body frame 1. A waste liquid flowing gap is provided between the stainless steel cross beams. First limit blocks are provided on the stainless steel cross beams. The wear test piece tray is detachably connected to the stainless steel cross beams by bolts. The first limit blocks are used to limit the wear test piece tray. Second limit blocks are provided on the wear test piece tray. The wear test piece forming tray 20 is placed on the wear test piece tray. The second limit blocks are used to limit the wear test piece forming tray 20. The wear test piece 2 is arranged inside the wear test piece forming tray 20 and is arranged below the wheel set system during the wear test. The wear test piece tray in this embodiment is welded by a high-strength stainless steel bottom plate and four high-strength stainless steel side plates. The internal dimensions of the wear test piece tray are 1000 mm in length, 1000 mm in width, and 50 mm in height. The wear test piece forming tray 20 is welded by a high-strength stainless steel bottom plate and four high-strength stainless steel side plates. The internal dimensions of the wear test piece forming tray 20 have two types, which are 500 mm in length, 500 mm in width, and 50 mm in height and 600 mm in length, 600 mm in width, and 50 mm in height respectively.

[0059] A waste liquid collection box 21 is further provided on the main body frame 1. The waste liquid collection box 21 is arranged below the stainless steel cross beam. A liquid level observation port and a drain port are provided on the waste liquid collection box 21. Drain holes are provided on the wear test piece tray. An anti-corrosion glass is provided on the liquid level observation port.

[0060] The environment simulation system includes a temperature control system, a wear test water spraying system, a wear test medium spraying system, and an ultraviolet irradiation aging system. The control system 3 is signal-connected to the temperature control system, the wear test water spraying system, the wear test medium spraying system, the ultraviolet irradiation aging system, and the wheel set rotation system.

[0061] The temperature control system includes a temperature sensor and a temperature controller 16. The temperature sensor is arranged inside the main body frame. The temperature controller 16 is arranged above the main body frame and is communicated with the main body frame through an air supply port. The wear test water spraying system includes a water pump, a water tank 17, a water pipe, and a nozzle. The water pump and the water tank 17 are arranged above the main body frame. The nozzle is arranged inside the main body frame. The nozzle is connected to the water tank through a water pipe. The wear test medium spraying system includes a sand box 18 and a sand spraying pipe. The sand spraying pipe is connected to the sand box. The sand box is arranged above the main body frame. The sand spraying pipe is arranged inside the main body frame. The ultraviolet irradiation aging system includes an ultraviolet lamp. The ultraviolet lamp is arranged below the fixed disk.

[0062] The test auxiliary support 22 is welded by high-strength stainless steel and is provided with four legs at the bottom. Universal wheels are installed on the four legs. The test auxiliary support is not connected to the high-strength main body frame and can move freely. When detecting the wear test piece after the completion of the stage test, the wear test piece tray together with the wear test piece forming tray is pulled out and placed on the test auxiliary support 22, which is convenient for subsequent wear resistance tests.

[0063] Embodiment 2

[0064] This embodiment discloses a method for testing the anti-slip and wear resistance performance of an anti-slip surface mixture by using the test device of Embodiment 1, including the following steps:

[0065] S1. Adjust the pressure exerted on the wear test piece by the test wheel set through the counterweight system;

[0066] S11. Calibrate the pressure values exerted on the wear test piece by the test wheel set under different counterweights, draw a counterweight calibration curve, and calculate the required counterweight for the test based on the required pressure value during the test and the counterweight calibration curve;

[0067] The specific steps for drawing the counterweight calibration curve are as follows:

[0068] A1. Use the wheel set lifting system to lift the wheel set system to the highest point and fix it, and install the wear test piece tray into the test device.

[0069] A2. Place a flat scale on the wear test piece tray, place a grid paper with copying function on the surface of the flat scale, release the fixation of the wheel set lifting system and place the test wheel on the grid paper.

[0070] A3. Increase the counterweight of the counterweight system and read the weight reading W1 of the flat scale.

[0071] A4. Use the wheel set lifting system to lift the test wheel to the highest position and fix it. Take out the grid paper, read and calculate the contact area M1 of the three test wheels on the grid paper, and calculate the pressure P1 exerted by the wheel set system on the wear test piece under the counterweight W1, where P1 = W1 / M1.

[0072] A5. Repeat steps A1 to A4 to read the weight readings W2, W3, W4, W5 of the flat scale and the contact areas M2, M3, M4, M5 on the grid paper respectively, and calculate the pressures P2, P3, P4, P5 exerted by the test wheel on the wear test piece under different counterweights respectively.

[0073] A6. Take the set weight reading W of the flat scale as the x-axis and the pressure P exerted by the wheel set system on the wear test piece under this counterweight as the y-axis to draw the counterweight calibration curve.

[0074] S12. Adjust the counterweight value of the counterweight system above the fixed disk based on the required counterweight for the test calculated in step S11.

[0075] S2. Form the wear test piece: Mix asphalt mixture using the test asphalt mixture mixer, spread the mixed asphalt mixture evenly on the wear test piece forming tray, and compact it using a small press to obtain the formed wear test piece. Test the initial dynamic friction coefficient, initial pendulum value, and initial texture depth of the wear test piece 2. The test method refers to the provisions in the "Field Test Regulations for Highway Subgrade and Pavement" (JTG 3450-2019).

[0076] S3. Use the wheel set lifting system to lift the wheel set system and place the wear test piece on the main frame below the wheel set system;

[0077] S4. Control the environmental conditions inside the main frame through the control system and the environmental simulation system to simulate the real road surface environment. Specifically, control the environmental temperature inside the main frame, the water spraying amount of the wear water spraying system, the sand spraying amount of the wear medium spraying system, and the ultraviolet lamp irradiation time through the control system;

[0078] Before the experiment starts, the water spraying amount of the wear water spraying system and the sand spraying amount of the wear medium spraying system can be calibrated first. The specific method is as follows:

[0079] Place a rain gauge under the water pipe of the wear water spraying system. Set different water spraying amounts A per unit time at certain intervals in the control system 3, then start the water pump to simulate rainfall. Record the rainfall data J through the rain gauge. Use the set different water spraying amounts A per unit time as the abscissa and the rainfall data J as the ordinate to draw a calibration curve, and establish the relationship between the water spraying amount A per unit time and the actual rainfall J. During the experiment, based on the predicted rainfall and this calibration curve, set the water spraying amount A per unit time.

[0080] Empty the wear medium in the sand box of the automatic sand spraying system, load 1000 g of wear medium into the sand box. Set the sand spraying amount B1 per unit time in the control system 3, start the automatic sand spraying system, and record the time T1 when all 1000 g of sand in the sand box is completely sprayed. Repeat the above steps, and set different sand spraying amounts B2, B3, B4, B5 per unit time respectively, and record the times T2, T3, T4, T5 when all 1000 g of sand in the sand box is completely sprayed; Use the set sand spraying amount B per unit time as the x-axis and the time T when all 1000 g of sand is completely sprayed as the y-axis to draw a calibration curve. During the experiment, calibrate the sand spraying amount based on this standard curve (because there is a certain error between the sand spraying amount controlled by the control system and the actual sand spraying amount of the automatic sand spraying system, so it can be calibrated through this calibration curve to ensure the accuracy of the experiment).

[0081] S5. Set the test time through the control system, set the rotation speed of the test wheel around the central axis of the fixed disk through the control system and the wheel set rotation system, remove the lifting rod, and start the test after the temperature in the main frame is stable;

[0082] S6. After the test is completed, place the test auxiliary support 22 beside the test device, use the wheel set lifting system to lift the wheel set system, take out the wear test piece tray, the wear test piece forming disk 20, and the wear test piece 2 and place them on the test auxiliary support 22, and test the dynamic rotational friction coefficient, skid value and texture depth of the wear test piece 2 again. The anti-slip and wear-resistant performance of the anti-slip surface mixture of the present invention is characterized by the dynamic rotational friction coefficient, skid value and texture depth.

[0083] If multiple tests are required, repeat S3 - S6 until the test is completed.

Claims

1. A device for testing the anti-skid and wear-resistant properties of anti-skid surface mixture, characterized in that: It includes a main frame (1), a wheelset system, a counterweight system, a wheelset rotation system, a wheelset lifting system, a wear specimen (2), an environmental simulation system and a control system (3). The wheelset system is located in the main frame (1), and comprises a fixed plate (4) and a test wheel (5) rotatably connected to the fixed plate (4); The counterweight system is arranged above the fixed plate (4); The wheelset rotation system comprises a rotating motor (6) and a rotating shaft (7); the rotating motor (6) is arranged above the main frame (1); the rotating shaft (7) extends into the main frame (1) and is clearance-matched with the fixed plate (4); The wheelset lifting system comprises two lever lifting assemblies symmetrically arranged on a fixed plate (4), the lever lifting assembly comprising a support (8), a lever (9) and a lifting rod (10), the support (8) being arranged above the main frame (1), the lever (9) being rotatably connected to the support (8), one end of the lifting rod (10) being detachably connected to the fixed plate (4), and the other end extending out of the main frame (1) and being rotatably and detachably connected to the lever (9); The wear test piece (2) is arranged on the main frame (1) below the wheelset system; The control system (3) is arranged above the main frame (1), and the control system (3) is connected to the environmental simulation system and the wheelset rotation system signals.

2. The anti-slip and wear-resistant performance testing device according to claim 1, characterized in that: There are three test wheels (5), three fixing seats (11) are arranged below the fixing plate (4), the test wheels (5) are rotatably connected to the fixing seats (11), and the vertical distances from the centers of the three test wheels (5) to the central axis of the fixing plate (4) are the same.

3. The anti-slip and wear-resistant performance testing device according to claim 1, characterized in that: The counterweight system comprises a plurality of counterweight plates (12), and counterweight plate fixing holes (13) and lifting rod through holes (14) are provided at the same positions on the plurality of counterweight plates (12) and the fixing plate (4). The counterweight plate (12) is provided with a long strip notch, and the rotating shaft (7) vertically passes through the long strip notch and extends to the bottom of the fixed plate (4). The wheelset lifting system also includes a lifting rod connecting piece, and the lifting rod (10) is connected to the lifting rod connecting piece after passing through the lifting rod through hole (14).

4. The anti-slip and wear-resistant performance testing device according to claim 3, characterized in that: The counterweight system further comprises a plurality of small counterweight blocks (15), each of which is provided with a counterweight block connector, and the counterweight block connector is adapted to fit the counterweight plate fixing hole (13).

5. The anti-slip and wear-resistant performance testing device according to claim 1, characterized in that: The environmental simulation system includes a temperature control system, an abrasion water spraying system, an abrasion medium spraying system and an ultraviolet irradiation aging system.

6. The anti-slip and wear-resistant performance testing device according to claim 5, characterized in that: The temperature control system comprises a temperature sensor and a temperature controller (16), wherein the temperature sensor is arranged inside the main frame (1), and the temperature controller (16) is arranged above the main frame (1) and is connected to the main frame (1) through an air supply port; The wear water spraying system comprises a water pump, a water tank (17), a water pipe and a nozzle, wherein the water pump and the water tank (17) are arranged above the main frame (1), the nozzle is arranged inside the main frame (1), and the nozzle is connected to the water tank (17) via a water pipe; The abrasive medium spraying system comprises a sand box (18) and a sand spreading pipe, wherein the sand spreading pipe is connected to the sand box (18), the sand box (18) is arranged above the main frame (1), and the sand spreading pipe is arranged inside the main frame (1); The ultraviolet irradiation aging system comprises an ultraviolet lamp, and the ultraviolet lamp is arranged below the fixing plate (4).

7. The anti-slip and wear-resistant performance testing device according to claim 1, characterized in that: The main frame (1) is provided with heat-insulating cotton inside, the main frame (1) is provided with observation ports (19) around it, the observation ports (19) are provided with heat-insulating glass, and the main frame (1) is provided with a door at the front and rear, respectively.

8. The anti-slip and wear-resistant performance testing device according to claim 1, characterized in that: A plurality of stainless steel beams are arranged in the middle of the main frame (1), gaps for waste liquid flow are arranged between the stainless steel beams, a first limit block is arranged on the stainless steel beam, the wear specimen tray is detachably connected to the stainless steel beam, a second limit block and a drainage hole are arranged on the wear specimen tray, the wear specimen forming tray (20) is placed on the wear specimen tray, and the wear specimen (2) is arranged in the wear specimen forming tray (20); The main frame (1) is also provided with a waste liquid collection box (21), which is arranged below the stainless steel crossbeam. The waste liquid collection box (21) is provided with a liquid level observation port and a drainage port.

9. A method for testing the anti-skid and wear-resistant properties of an anti-skid surface mixture, characterized in that: The anti-slip and wear-resistant performance testing device according to any one of claims 1 to 8 is used for testing, comprising the following steps: S1, adjusting the pressure applied by the test wheel (5) to the wear specimen (2) through the counterweight system; S2, forming a wear specimen: using an asphalt mixture mixer for testing to mix an asphalt mixture, spreading the mixed asphalt mixture onto a wear specimen forming plate (20), compacting it using a small press to obtain a formed wear specimen (2), and testing the initial dynamic rotational friction coefficient, initial pendulum value and initial structural depth of the wear specimen (2); S3. Lift the wheelset system using the wheelset lifting system, and place the wear test piece (2) on the main frame (1) below the wheelset system; S4, controlling the environmental conditions in the main frame (1) through the control system (3) and the environmental simulation system to simulate a real road environment; S5, setting the test time through the control system (3), setting the rotation speed of the test wheel (5) around the central axis of the fixed plate (4) through the control system (3) and the wheelset rotation system, removing the lifting rod (10), and starting the test; S6. After the test is completed, the wear specimen (2) is taken out and the dynamic rotational friction coefficient, pendulum value and structural depth of the wear specimen (2) are tested again.

10. The anti-slip and wear-resistant performance testing method according to claim 9, characterized in that: Step S1 is specifically as follows: S11, calibrating the pressure value applied by the test wheel (5) to the wear test piece (2) under different counterweights, drawing a counterweight calibration curve, and calculating the counterweight required for the test based on the pressure value required to be achieved during the test and the counterweight calibration curve; S12, based on the counterweight required for the test calculated in step S11, adjusting the counterweight value of the counterweight system above the fixed plate (4).

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