Visual test system for friction performance of asphalt pavement

Abstract

The invention discloses a visual test system for the friction performance of an asphalt pavement, and belongs to a friction force test system in the technical field of pavement test experimental equipment.The technical scheme is that a cavity is formed in a box body and used for friction test operation; an asphalt pavement test sample is arranged in the box body, and the asphalt pavement test sample is provided with a horizontal plane; the sliding block device is arranged in the box body and is used for the frictional contact of the asphalt pavement test sample; a sliding block device is arranged in the box body, a temperature control device is arranged on one side in the box body, three layers of perforated shunting baffles are arranged at the output end of the temperature control device, a strain force acquisition instrument is arranged outside the box body, and the tail end of the sliding block device is connected with the strain force acquisition instrument; the upper end of the box body is made of a transparent material and is externally provided with a high-speed camera; the invention provides a visual test system for the friction performance of an asphalt pavement, which is used for accurately and effectively testing the friction performance of the asphalt pavement.

Description

Technical Field

[0001] The invention belongs to the technical field of road surface testing experimental equipment, and in particular relates to a visual testing system for friction performance of an asphalt road surface. Background Art

[0002] At present, there are few reports on the research of asphalt pavement under complex plateau environments and working conditions. The research on the friction performance of the pavement is quite scarce, mainly due to the great limitations of the testing equipment, which directly restricts the upgrading and replacement of related industries and poses a great challenge to driving safety. Therefore, the present invention has the function of testing the friction performance of asphalt pavement under different environments such as temperature and humidity changes and complex working conditions such as wettability, icing, and sand. The use of visualization modules and high-precision force sensors effectively improves the accuracy of test data. The promotion of this equipment will effectively promote the development of plateau transportation.

[0003] According to the existing literature research, up to now, the friction performance test device of asphalt pavement is limited to testing at room temperature, and there is no visual test device. In addition, the friction force is measured indirectly, which has certain errors. In view of the above considerations, the applicant designed a visual test device for the friction performance of asphalt pavement in complex environments and working conditions. Summary of the invention

[0004] The purpose of the present invention is to provide a visual testing system for the friction performance of asphalt pavement, by setting up an environment in a box to adjust the temperature and humidity of the asphalt pavement test sample, and performing friction testing through a slider device and strain force collection, thereby accurately and effectively testing the friction performance of the asphalt pavement.

[0005] The object of the present invention is achieved by providing a visual testing system for friction performance of an asphalt pavement, comprising:

[0006] A box body, wherein the box body has a cavity inside for friction test operation;

[0007] An asphalt pavement test sample, the asphalt pavement test sample is placed in the box, and the asphalt pavement test sample is provided with a horizontal surface;

[0008] a slider device, the slider device being arranged in the box body and used for frictional contact with the asphalt pavement test sample; and

[0009] A temperature control device is provided on one side of the box body, a three-layer perforated flow dividing baffle is provided at the output end of the temperature control device, a strain force collector is provided outside the box body, and the end of the slider device is connected to the strain force collector;

[0010] The upper end of the box is made of transparent material and a high-speed camera is arranged on the outside.

[0011] Furthermore, a blind hole is provided on the side of the box body, and the blind hole is provided on a side opposite to the temperature control device. The traction rope in the slider device passes through the blind hole and is connected to the strain force collector.

[0012] Furthermore, the box body is provided with a nitrogen hole, and the nitrogen hole is arranged on one side of the blind hole.

[0013] Furthermore, the slider device includes a first fixed pulley vertically rotatably arranged in the box and a second fixed pulley vertically rotatably arranged outside the box, the traction rope is arranged between the first fixed pulley and the second fixed pulley, a slider group is fixedly arranged on the traction rope, the slider group is placed on the upper surface of the asphalt pavement test sample, and a counterweight block is arranged at the other end of the traction rope.

[0014] Furthermore, the three-layer perforated diversion baffle includes a first layer, a second layer and a third layer, which are vertically arranged in sequence in the direction of the asphalt pavement test sample, a first air flow hole group is arranged in the middle of the first layer, a second air flow hole group is arranged at the upper and lower ends of the second layer, and a third air flow hole group is arranged in the middle of the third layer.

[0015] Furthermore, the length of the third air flow hole group distribution is greater than the length of the first air flow hole group distribution.

[0016] Furthermore, the temperature control device includes a refrigeration device and a heating device.

[0017] Furthermore, a plurality of thermometers and hygrometers are evenly distributed inside the asphalt pavement test sample.

[0018] Furthermore, a humidifying device is arranged inside the box.

[0019] Furthermore, the traction rope is a high-elastic wire, and the slider group includes a main slider fixedly connected to the traction rope and a secondary slider arranged on the main slider, and the secondary slider is fixedly connected to the main slider by low-temperature glue.

[0020] The beneficial effects of the present invention are embodied in:

[0021] 1. In the present invention, an asphalt pavement test sample is set in the cavity of a set experimental box, and the environment in the box is controllably adjusted and simulated by a temperature control device, and a slider device and a strain collector are set in the box. The friction force of the asphalt pavement test sample on the slider device is accurately collected by the strain collector, thereby realizing the test of friction force. More specifically, since a three-layer perforated diversion baffle is set at the output end of the temperature control device, the three-layer perforated diversion baffle can realize faster and more uniform control of the heating of the asphalt pavement test sample, thereby improving the accuracy and stability of the friction test of the asphalt pavement test sample. At the same time, a high-speed camera outside the box collects the experimental conditions in the box, and while having a visual test, it also collects the experimental conditions in real time.

[0022] 2. In the present invention, since a blind hole is provided on the side of the box, the traction rope in the slider device is placed between the inside and outside of the box. Under the action of the moving slider device, the strain force collector connected to the outside of the traction rope is controlled by force. In particular, since through holes such as blind holes are provided, it is also beneficial to quickly exhaust the air in the box when the box is ventilated with nitrogen, thereby effectively ensuring the stability of the experimental environment in the box and improving the accuracy of friction force detection.

[0023] 3. In the present invention, by providing a nitrogen hole on the box body and placing the nitrogen hole on one side of the blind hole, it is convenient to introduce nitrogen into the cavity in the box body and to exhaust the air in the cavity.

[0024] 4. In the present invention, since the first fixed pulley and the second fixed pulley are arranged in the slider device, the traction rope is supported and processed. The traction rope passes through the first fixed pulley and the second fixed pulley in sequence to pull the slider group and connect the counterweight block arranged on the other end of the traction rope after being stressed. Therefore, when the slider group is placed on the upper surface of the asphalt pavement test sample for pulling, the force can be controlled and adjusted, and the force during the experiment can be controlled, which is conducive to the accurate testing of friction data.

[0025] 5. In the present invention, a three-layer perforated diversion baffle is arranged at the heat control position in the cavity. When heat is dissipated from the source, the heat is dissipated more evenly and close to the asphalt pavement test sample through the three-layer perforated diversion baffle. More specifically, the first layer, the second layer and the third layer are arranged in sequence in the direction of heat dissipation, and air flow hole groups are arranged in the first layer, the second layer and the third layer. At the same time, the first layer is provided with a first air flow hole group in the middle, the second layer is provided with a second air flow hole group at the upper and lower ends of the second layer, and the third layer is provided with a third air flow hole group in the middle. This arrangement greatly improves the uniformity of heat transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0027] Figure 1 It is a structural schematic diagram of the friction force testing system of the present invention;

[0028] Figure 2 It is a schematic diagram of the structure of the three-layer perforated diversion baffle of the present invention.

[0029] In the accompanying drawings, 1-box, 2-asphalt pavement test sample, 3-slider device, 4-temperature control device, 5-three-layer open hole diversion baffle, 6-strain force collector, 7-high-speed camera, 8-blind hole, 9-traction rope, 10-nitrogen hole, 11-first fixed pulley, 12-second fixed pulley, 13-slider group, 14-counterweight block, 15-first layer plate, 16-second layer plate, 17-third layer plate, 18-first air flow hole group, 19-second air flow hole group, 20-third air flow hole group, 21-refrigeration device, 22-heating device, 23-humidification device, 24-main slider, 25-secondary slider. DETAILED DESCRIPTION

[0030] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0031] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0032] Reference Figure 1 and Figure 2, a visual testing system for friction performance of asphalt pavement, comprising:

[0033] A box 1, wherein the box 1 has a cavity inside for friction test operation;

[0034] An asphalt pavement test sample 2, the asphalt pavement test sample 2 is placed in the box 1, and the asphalt pavement test sample 2 is provided with a horizontal surface;

[0035] A slider device 3, the slider device 3 is arranged in the box body 1 and is used for friction contact with the asphalt pavement test sample 2; and

[0036] A temperature control device 4 is provided on one side of the box body 1, and a three-layer perforated flow dividing baffle 5 is provided at the output end of the temperature control device 4. A strain force collector 6 is provided outside the box body 1, and the end of the slider device 3 is connected to the strain force collector 6;

[0037] The upper end of the box body 1 is made of transparent material and a high-speed camera 7 is arranged on the outside.

[0038] By setting an asphalt pavement test sample 2 in the cavity of the set experimental box 1, and controlling and simulating the environment in the box 1 through the temperature control device 4, and setting a slider device 3 and a strain force collector 6 in the box 1, the friction force of the slider device 3 on the asphalt pavement test sample 2 is accurately collected through the strain force collector 6, thereby realizing the friction test. More specifically, since a three-layer open hole diversion baffle 5 is provided at the output end of the temperature control device 4, the three-layer open hole diversion baffle 5 can realize faster and more uniform control of the heating of the asphalt pavement test sample 2, thereby improving the accuracy and stability of the friction test of the asphalt pavement test sample 2. At the same time, the high-speed camera 7 outside the box 1 collects the experimental conditions in the box 1, and while having a visual test, it also collects the experimental conditions in real time.

[0039] As a preferred embodiment of this embodiment, the high-speed camera 7 can be suspended above the box 1 or be arranged above the high-speed camera 7 through fixed support of a bracket.

[0040] Preferably, a blind hole 8 is provided on the side of the box body 1 , and the blind hole 8 is provided on the side opposite to the temperature control device 4 . The traction rope 9 in the slider device 3 passes through the blind hole 8 and is connected to the strain force collector 6 .

[0041] It can be understood that, since the blind hole 8 is provided on the side of the box body 1, the traction rope 9 in the slider device 3 is placed between the inside of the box body 1 and the outside of the box body 1. Under the action of the moving slider device 3, the strain force collector 6 connected to the outside of the traction rope 9 is controlled by force. Among them, since through holes such as the blind hole 8 are provided, it is also beneficial to quickly exhaust the air in the box body 1 when the box body 1 is ventilated with nitrogen, thereby effectively ensuring the stability of the experimental environment in the box body 1 and improving the accuracy of friction force detection.

[0042] Preferably, the box body 1 is provided with a nitrogen hole 10 , and the nitrogen hole 10 is arranged on one side of the blind hole 8 .

[0043] By providing the nitrogen hole 10 on the box body 1 and placing the nitrogen hole 10 on one side of the blind hole 8, it is convenient to introduce nitrogen into the cavity in the box body 1 and to exhaust the air in the cavity.

[0044] Preferably, the slider device 3 includes a first fixed pulley 11 vertically rotatably arranged in the box body 1 and a second fixed pulley 12 vertically rotatably arranged outside the box body 1, the traction rope 9 is arranged between the first fixed pulley 11 and the second fixed pulley 12, a slider group 13 is fixedly arranged on the traction rope 9, the slider group 13 is placed on the upper surface of the asphalt pavement test sample 2, and a counterweight block 14 is arranged at the other end of the traction rope 9.

[0045] It can be understood that since the first fixed pulley 11 and the second fixed pulley 12 are provided in the slider device 3, the traction rope 9 is supported, and the traction rope 9 passes through the first fixed pulley 11 and the second fixed pulley 12 in sequence, so as to pull the slider group 13 and connect the counterweight block 14 provided on the other end of the traction rope 9 after being subjected to force. Therefore, when the slider group 13 is placed on the upper surface of the asphalt pavement test sample 2 for pulling, the force can be controlled and adjusted, and the force during the experiment can be controlled, which is conducive to the accurate testing of friction data.

[0046] Preferably, the three-layer perforated diversion baffle 5 includes a first layer plate 15, a second layer plate 16 and a third layer plate 17 which are vertically arranged in sequence in the direction of the asphalt pavement test sample 2, a first air flow hole group 18 is arranged in the middle of the first layer plate 15, a second air flow hole group 19 is arranged at the upper and lower ends of the second layer plate 16, and a third air flow hole group 20 is arranged in the middle of the third layer plate 17.

[0047] Preferably, the length of the third air flow hole group 20 is greater than the length of the first air flow hole group 18.

[0048] By setting a three-layer perforated diversion baffle 5 at the heat control position in the cavity, when the heat is dissipated from the source, the three-layer perforated diversion baffle 5 makes the heat dissipation and close to the asphalt pavement test sample 2 more uniform. More specifically, the first layer 15, the second layer 16 and the third layer 17 are sequentially arranged in the direction of heat dissipation, and the first layer 15, the second layer 16 and the third layer 17 are all provided with air flow hole groups. At the same time, the middle part of the first layer 15 is provided with a first air flow hole group 18, the upper and lower ends of the second layer 16 are provided with a second air flow hole group 19, and the middle part of the third layer 17 is provided with a third air flow hole group 20. This arrangement greatly improves the uniformity of heat transfer.

[0049] Preferably, the temperature control device 4 includes a refrigeration device 21 and a heating device 22 .

[0050] The setting of the refrigeration device 21 and the heating device 22 realizes temperature control, thereby achieving temperature change of the experimental environment.

[0051] Preferably, a plurality of thermometers and hygrometers are evenly distributed inside the asphalt pavement test sample 2.

[0052] Thus, the temperature and humidity of the asphalt pavement test sample 2 can be monitored in real time.

[0053] As a preferred mode of this embodiment, a humidifying device 23 is arranged inside the box 1. The setting of the humidifying device 23 can enrich the state of the asphalt pavement test sample 2 under different humidity conditions to meet the diversity of the experimental environment.

[0054] Preferably, the traction rope 9 is a high elastic wire, and the slider group 13 includes a main slider 24 fixedly connected to the traction rope 9 and a secondary slider 25 arranged on the main slider 24, and the secondary slider 25 is fixedly connected to the main slider 24 by low-temperature glue.

[0055] Working principle and working process of the present invention:

[0056] When the asphalt pavement friction performance visualization test system provided by the present invention is used, before the experiment, nitrogen is discharged into the box 1 through the nitrogen hole, the air in the device is exhausted, the residual moisture in the air and other factors are prevented from interfering, and the three-layer diversion baffle is used to make the test sample evenly heated and cooled, so as to prevent it from being only locally affected and unevenly heated and cooled as a whole. Eight thermometers and hygrometers are arranged on the asphalt block respectively to facilitate the acquisition of the overall spatial temperature of the asphalt, and the test can be carried out only when the temperature and humidity values ​​of each area are consistent. The device is provided with an observation window, and the entire friction behavior of the asphalt block is observed in real time in combination with a high-resolution camera. The device adopts a fixed pulley transmission method to realize the plane friction between the concrete roadbed surface and the slider, wherein the slider and the high-precision strain sensor are connected by a high-elastic line, so as to eliminate the influence of the deformation of the traction line on the test data as much as possible. Considering the temperature and humidity change factors in the cavity, this project adopts low-temperature glue (Varnish) to paste the friction pair and the counterweight block, and the positive pressure generated by the relative sliding process between the slider and the asphalt block is regulated by changing the mass of the counterweight block.

[0057] More specifically, since a three-layer perforated diversion baffle 5 is provided at the output end of the temperature control device 4, the three-layer perforated diversion baffle 5 can achieve faster and more uniform control of the heating of the asphalt pavement test sample 2, thereby improving the accuracy and stability of the friction test on the asphalt pavement test sample 2; at the same time, the high-speed camera 7 outside the box 1 collects the experimental conditions in the box 1, and while having a visual test, it also collects the experimental conditions in real time.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A visual testing system for friction performance of asphalt pavement, characterized in that: include: A box (1), wherein the box (1) has a cavity inside for performing a friction test; An asphalt pavement test sample (2), the asphalt pavement test sample (2) being placed in the box (1), and the asphalt pavement test sample (2) being provided with a horizontal surface; A slider device (3), the slider device (3) being arranged in the box (1) and used for frictional contact with the asphalt pavement test sample (2); and A temperature control device (4) is provided on one side of the interior of the box (1), a three-layer perforated flow dividing baffle (5) is provided at the output end of the temperature control device (4), a strain force collector (6) is provided outside the box (1), and the end of the slider device (3) is connected to the strain force collector (6); The upper end of the box (1) is made of a transparent material and a high-speed camera (7) is arranged on the outside.

2. The asphalt pavement friction performance visual testing system according to claim 1 is characterized in that: A blind hole (8) is provided on the side of the box body (1), and the blind hole (8) is provided on a side opposite to the temperature control device (4). The traction rope (9) in the slider device (3) passes through the blind hole (8) and is connected to the strain force collector (6).

3. The asphalt pavement friction performance visual testing system according to claim 2 is characterized in that: The box body (1) is provided with a nitrogen hole (10), and the nitrogen hole (10) is arranged on one side of the blind hole (8).

4. The asphalt pavement friction performance visual testing system according to claim 2, characterized in that: The slider device (3) comprises a first fixed pulley (11) vertically rotatably arranged in the box (1) and a second fixed pulley (12) vertically rotatably arranged outside the box (1); the traction rope (9) is arranged between the first fixed pulley (11) and the second fixed pulley (12); a slider group (13) is fixedly arranged on the traction rope (9); the slider group (13) is placed on the upper surface of the asphalt pavement test sample (2); and a counterweight block (14) is arranged at the other end of the traction rope (9).

5. The asphalt pavement friction performance visual testing system according to claim 1 is characterized in that: The three-layer perforated flow diversion baffle (5) comprises a first layer plate (15), a second layer plate (16) and a third layer plate (17) which are vertically arranged in sequence in the direction of the asphalt pavement test sample (2); a first air flow hole group (18) is arranged in the middle of the first layer plate (15); a second air flow hole group (19) is arranged at the upper and lower ends of the second layer plate (16); and a third air flow hole group (20) is arranged in the middle of the third layer plate (17).

6. The asphalt pavement friction performance visual testing system according to claim 5, characterized in that: The length of the third air flow hole group (20) is greater than the length of the first air flow hole group (18).

7. The asphalt pavement friction performance visualization test system according to claim 1, characterized in that: The temperature control device (4) comprises a refrigeration device (21) and a heating device (22).

8. The asphalt pavement friction performance visualization test system according to claim 1, characterized in that: A plurality of thermometers and hygrometers are evenly distributed inside the asphalt pavement test sample (2).

9. The asphalt pavement friction performance visualization test system according to claim 1, characterized in that: A humidifying device (23) is arranged inside the box (1).

10. The asphalt pavement friction performance visual testing system according to claim 4, characterized in that: The traction rope (9) is a highly elastic wire, and the slider group (13) comprises a main slider (24) fixedly connected to the traction rope (9) and a secondary slider (25) arranged on the main slider (24), and the secondary slider (25) is fixedly connected to the main slider (24) by low-temperature glue.

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