CN112986121A

CN112986121A - Accelerated aging evolution test equipment for asphalt and mixture under simulated western conditions

Info

Publication number: CN112986121A
Application number: CN202110390459.7A
Authority: CN
Inventors: 冯小伟; 支鹏飞; 马红梅; 张岩; 田鑫新; 李斌斌; 高永博
Original assignee: Gansu Academy Of Transportation Sciences Group Co ltd
Current assignee: Gansu Academy Of Transportation Sciences Group Co ltd
Priority date: 2021-04-12
Filing date: 2021-04-12
Publication date: 2021-06-18

Abstract

The invention discloses test equipment for simulating accelerated aging evolution of asphalt and mixtures under western conditions; the device comprises a fixed frame, a sample transferring system, a dry-wet/freeze-thaw test system, an ultraviolet aging test system and a control cabinet; wherein, the sample transfer system is arranged on the fixed frame; the dry-wet/freeze-thaw test system comprises a first sample box arranged on the fixed frame, and a heating device, a refrigerating system and a spraying system which are arranged on the fixed frame and respectively act on the first sample box; the ultraviolet aging test system comprises a second sample box and an ultraviolet irradiation device; the refrigerating system is also connected with a second sample box; the control cabinet is respectively and electrically connected with the dry-wet/freeze-thaw test system, the ultraviolet aging test system and the sample transfer system. The device can comprehensively simulate the performances of the asphalt and the mixture in different states, and provides technical support for optimizing the performances of the asphalt and the mixture and scientifically and reasonably evaluating the service state of the asphalt pavement.

Description

Accelerated aging evolution test equipment for asphalt and mixture under simulated western conditions

Technical Field

The invention belongs to the technical field of asphalt and asphalt mixture durability test, and particularly relates to test equipment for simulating accelerated aging evolution of asphalt and mixtures under western conditions.

Background

With the rapid development of economic construction in China in recent years, the construction of highway infrastructure in western regions also comes up to a rapid development stage, and asphalt pavements have become the main form of pavement structures in western regions due to excellent pavement performance. However, the western regions (especially the western high-cold high-altitude regions) become one of the major difficulties in the road construction in China due to the special climatic environments of high altitude, large temperature difference, strong ultraviolet radiation and the like. The performance damage of the asphalt pavement caused by repeated dry-wet cycle, freeze-thaw cycle, thermal oxygen aging, ultraviolet aging and the like is more serious than that of other areas, and the performance damage becomes a factor influencing the service life of the asphalt pavement to be not negligible. At present, the evaluation of asphalt materials in engineering construction is only the performance evaluation of products on site and the performance evaluation after short-term thermal-oxidative aging in the construction process; the evaluation of the asphalt mixture is only the evaluation of the high-temperature, low-temperature and water stability of the fresh mixture, and the influences of dry-wet cycle, freeze-thaw cycle, thermal-oxidative aging, ultraviolet aging and the like on the asphalt pavement in the service process and the specific influences of the factors on the asphalt and the mixture are not considered at all, and the factors have significant and serious influences on the construction of the asphalt pavement in western regions and the service process and are one of important factors causing the early damage of the asphalt pavement.

The prior art lacks equipment capable of carrying out comprehensive evolution tests on dry-wet cycle, freeze-thaw cycle, thermal-oxidative aging and ultraviolet aging of asphalt and asphalt mixtures.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides test equipment for simulating accelerated aging evolution of asphalt and mixtures under western adverse environmental conditions; the device can comprehensively evaluate the performance state of the asphalt pavement in western regions under adverse weather conditions such as dry-wet cycle, freeze-thaw cycle, thermo-oxidative aging and ultraviolet aging.

In order to achieve the purpose, the invention adopts the technical scheme that:

asphalt and mixture accelerated aging evolution test equipment under simulated western conditions comprises:

the whole fixed frame is of a cubic frame structure;

the sample transferring system is arranged on the fixed frame;

the dry-wet/freeze-thaw test system comprises a first sample box arranged on a fixed frame, and a heating device, a refrigerating system and a spraying system which are arranged on the fixed frame and respectively act on the first sample box;

the ultraviolet aging test system comprises a second sample box and an ultraviolet irradiation device; the refrigerating system is also connected with a second sample box; and

and the control cabinet is electrically connected with the dry-wet/freeze-thaw test system, the ultraviolet aging test system and the sample transfer system respectively.

Further, first sample case and second sample case all include the case lid of box and lock at the box top, the box outer wall is equipped with the heat preservation, the inside multilayer carrier that vertically is equipped with of edge of box, be equipped with temperature and humidity sensor in the box in the first sample case, be equipped with temperature sensor in the box in the second sample case, temperature and humidity sensor and temperature sensor are connected with the switch board electricity respectively.

Furthermore, the heating device comprises a connecting seat arranged on the outer wall of the box body and a heating pipe which is arranged on the connecting seat, extends into the box body and is spirally arranged, and the connecting seat is electrically connected with the control cabinet.

Further, the spraying system comprises a water tank arranged on the fixed frame, a water pump connected with the water tank, a plurality of spray heads arranged in the tank body and longitudinally distributed, a water collecting tank arranged at the bottom of the tank body, and an electric three-way valve simultaneously connected with the water pump, the spray heads and the water collecting tank through pipelines; the bottom of the box body is provided with an electric valve, and an outlet of the electric valve is communicated with the water collecting tank.

Furthermore, the refrigerating system comprises a compressor arranged on the fixed frame, a condenser coil connected with the compressor, an evaporator coil connected with the compressor, and a fan arranged on the fixed frame; the evaporator coil is arranged on the box body of the first sample box, the condenser coil is arranged on the box body of the second sample box, the compressor is electrically connected with the electric control cabinet, and the fan is communicated with the box body of the second sample box.

Further, the ultraviolet irradiation device comprises a plurality of ultraviolet lamps which are arranged in the second sample box body and electrically connected with the control cabinet, and the ultraviolet lamps are longitudinally distributed.

Further, the sample transfer system comprises a parallel guide rail arranged at the top of the fixed frame, a walking trolley matched with the parallel guide rail, and a telescopic mechanical arm arranged on the walking trolley longitudinally, wherein the walking trolley and the telescopic mechanical arm are electrically connected with the control cabinet.

Further, the telescopic mechanical arm comprises a telescopic sleeve arranged on the walking trolley, a U-shaped claw arranged at the lower end of the telescopic sleeve, and a first winch and a second winch which are arranged on the walking trolley; the free end of the U-shaped claw is hinged with a swinging tooth, one end of a rope of the first winch is connected with the swinging tooth, one end of a rope of the second winch is connected with the U-shaped claw, and the first winch and the second winch are respectively and electrically connected with the control cabinet.

Furthermore, a conversion table is arranged between the parallel guide rails on the top of the fixed frame.

The invention has the beneficial effects that:

the device fully considers the service environment of the asphalt pavement in western regions under adverse climatic conditions such as dry-wet cycle, freeze-thaw cycle, thermo-oxidative aging and ultraviolet aging, comprehensively simulates the performances of asphalt and mixtures in different states, and provides technical support for optimizing the performances of the asphalt and the mixtures in western regions and scientifically and reasonably evaluating the service state of the asphalt pavement;

the invention uses the evaporator coil in the refrigeration system to refrigerate the first sample box, uses the heating device to heat, and provides the cold/hot condition for the freezing and thawing cycle test; the heating device is also matched with the spraying system, so that the first sample box can also be used for a dry-wet cycle test; a condenser coil in the refrigeration system participates in an evolution test of a second sample box to heat the second sample box, provide thermal conditions for thermal oxidation aging and ultraviolet aging, and can assist in completing the thermal oxidation aging and ultraviolet aging tests;

according to the invention, the samples are stored and taken through the telescopic mechanical arm on the structural design, and the telescopic mechanical arm enables the components extending into the first sample box and the second sample box to be mechanical storage transmission components on the structural design, so that the sample storage and taking device is suitable for sample storage and taking operations in different cold and hot environments.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic side view of the present invention

FIG. 3 is a schematic top view of the present invention;

FIG. 4 is a schematic top view of the internal structure of the first sample chamber according to the present invention;

FIG. 5 is a schematic top view of the internal structure of a second sample chamber according to the present invention;

FIG. 6 is a schematic view of the telescopic robot arm of the present invention;

fig. 7 is a system control block diagram of the present invention.

Wherein, 1-a fixed frame; 2-a first sample box; 3-a second sample box; 4-a control cabinet; 5-a box body; 6-box cover; 7-insulating layer; 8-a carrier; 9-a temperature and humidity sensor; 10-a temperature sensor; 11-a connecting seat; 12-heating a tube; 13-a water tank; 14-a water pump; 15-a spray head; 16-a water collection tank; 17-an electric three-way valve; 18-an electrically operated valve; 19-a compressor; 20-condenser coil; 21-evaporator coil; 22-a fan; 23-ultraviolet lamp; 24-parallel guide rails; 25-a walking trolley; 26-a telescopic sleeve; 27-U-shaped jaws; 28-a first winder; 29-a second hoist; 30-oscillating teeth; 31-converting station.

Detailed Description

The preferred embodiments of the present invention are described below with reference to the accompanying drawings:

as shown in fig. 1 to 7, an accelerated aging evolution test apparatus for asphalt and mixture under western conditions was simulated; the device comprises a fixing frame 1, a sample transferring system, a dry-wet/freeze-thaw test system, an ultraviolet aging test system and a control cabinet 4. The fixing frame 1 provides supporting and fixing functions for other components; the sample transferring system is used for transferring the test; the dry-wet/freeze-thaw test system and the ultraviolet aging test system are mainly used for a dry-wet cycle test, a freeze-thaw cycle test, a thermo-oxidative aging test and an ultraviolet aging test; the control cabinet 4 is used for controlling the electric control equipment.

The whole fixed frame 1 is of a cubic frame structure, and universal wheels can be arranged at the bottom of the fixed frame for convenient movement; a conversion table 31 is arranged between the parallel guide rails 24 on the top of the fixed frame 1, and the conversion table 31 is used for temporarily storing the object carriers 8 and the box covers.

The sample transferring system is arranged at the top of the fixing frame 1; specifically, the sample transfer system comprises parallel guide rails 24, a walking trolley 25 and a telescopic mechanical arm. The parallel guide rail 24 is fixed on the top of the fixed frame 1 and provides a guiding function for the walking trolley 25. The walking trolley 25 comprises a U-shaped frame body, rollers which are arranged on the edge of the U-shaped frame body and matched with the guide rails, and a motor which is arranged on the U-shaped frame body and is in transmission connection with the rollers through a synchronous belt. The telescopic mechanical arm comprises a telescopic sleeve 26, a U-shaped claw 27, a first winch 28 and a second winch 29; the telescopic sleeve 26 is composed of a plurality of rectangular cylinders which are nested with each other; the top end of the telescopic sleeve 26 is fixedly connected with the U-shaped frame body of the walking trolley 25, and the lower end of the telescopic sleeve 26 is fixedly connected with a U-shaped claw 27; the free end edge of the U-shaped claw 27 is hinged with a swinging tooth 30; the first winch 28 and the second winch 29 are both arranged on the traveling trolley 25 and are respectively and electrically connected with the control cabinet 4; one end of a rope of the first winch 28 is connected with the swinging teeth 30 after being guided and displaced by the pulley, and can preferentially drive the swinging teeth 30 to move; one end of the rope of the second winding machine 29 is connected with the U-shaped claw 27, and is used for driving the U-shaped claw 27 to perform lifting action.

The dry-wet/freeze-thaw test system comprises a first test sample box 2 arranged on a fixing frame 1, and a heating device, a refrigerating system and a spraying system which are arranged on the fixing frame 1 and respectively act on the first test sample box 2. The first sample box 2 comprises a box body 5 and a box cover 6 buckled at the top of the box body 5; the box cover 6 is provided with an exhaust pipe and a hanging ring, the exhaust pipe is used for adjusting pressure balance, the hanging ring is used for being matched with a shrinking mechanical arm to realize opening and closing control of the box cover 6, the cylindrical outer wall of the box body 5 is provided with a heat insulation layer 7, and the heat insulation layer 7 can adopt a polyurethane foaming layer; the interior of the box body 5 is longitudinally provided with a plurality of layers of object carriers 8, the object carriers 8 can be specifically provided with three groups and are arranged at the upper, middle and lower positions of the box body, the object carriers 8 specifically comprise brackets arranged in the interior of the box body and sample net racks lapped on the brackets, the sample net racks are flat, the sizes of the three sample net racks are reduced one by one, and the three sample net racks with the smallest sizes are placed at the lower side of the box body 5, so that the arrangement design is convenient for the storage and the taking of the three sample net; a temperature and humidity sensor 9 is arranged in the box body 5 in the first sample box 2, and the temperature and humidity sensor 9 is electrically connected with the control cabinet 4. The heating device adopts an electric heating mode and comprises a connecting seat 11 arranged on the outer wall of the box body 5 and a heating pipe 12 which is arranged on the connecting seat 11, extends into the box body and is spirally arranged; the connecting seat 11 is electrically connected with the control cabinet 4. The refrigeration system includes a compressor 19, a condenser coil 20, an evaporator coil 21 and a blower 22; the compressor 19 is fixed on the fixing frame, and the compressor 19 is respectively connected with the condenser coil 20 and the evaporator coil 21; the condenser coil 20 and the evaporator coil 21 are provided with polyurethane foaming heat insulation layers on the outer pipeline of the box body 5; the evaporator coil 21 is arranged on the box body 5 and avoids the heating pipe 12; the condenser coil 20 is arranged on the box body 5 of the second sample box 3; the refrigerating part of the refrigerating system is used for refrigerating the first sample box 2, and the heating component of the refrigerating system is used on the second sample box 3; the fan 22 is arranged on the fixed frame 1 and communicated with the box body 5 of the second sample box 3 for regulating the temperature of the second sample box 3. The spraying system comprises a water tank 13, a water pump 14, a spray head 15, a water collecting tank 16 and an electric three-way valve 17; the water tank 13 is fixed on the fixed frame 1; the water pump 14 is arranged on the fixed frame 1 and communicated with the water tank 13; three spray heads 15 are fixed on the box body 5 and longitudinally distributed, and the spraying direction of the spray heads 15 corresponds to the object carrier 8; the water collecting tank 16 is arranged on the fixed frame and positioned at the lower end of the tank body 5, the bottom of the tank body 5 is provided with an electric valve 18, and the outlet of the electric valve 18 is communicated with the water collecting tank 16; the electric three-way valve 17 is connected with the water pump 14, the spray head 15 and the water collecting tank 16 at the same time to realize water circulation.

The ultraviolet ray aging test system comprises a second sample box 3 and an ultraviolet irradiation device. The second sample box 3 also comprises a box body 5 and a box cover 6, an exhaust pipe and a hanging ring are arranged on the box cover 6, the exhaust pipe is used for adjusting pressure balance, the hanging ring is used for being matched with a shrinkage mechanical arm to realize opening and closing control of the box cover 6, the box body 5 is in a barrel shape or a square barrel shape, and the outer wall of the box body is also provided with a heat insulation layer 7; a temperature sensor 10 is arranged in the box body 5 in the second sample box 3, and a temperature and humidity sensor 9 is electrically connected with the control cabinet 4. The ultraviolet irradiation device comprises an ultraviolet lamp 23 which is arranged in the second sample box body 5 and is electrically connected with the control cabinet 4, and three layers of ultraviolet lamps 23 are longitudinally distributed for carrying out ultraviolet irradiation on the samples.

The control cabinet 4 is respectively and electrically connected with corresponding electric components in the dry-wet/freeze-thaw test system, the ultraviolet aging test system and the sample transfer system. The control cabinet 4 can comprise a cabinet body, a touch display screen and a PLC (programmable logic controller) which are arranged on the cabinet body; the PLC controller is respectively connected with a touch display screen, a temperature and humidity sensor 9, a temperature sensor 10, a connecting seat 11, a water pump 14, an electric three-way valve 17, an electric valve 18, a compressor 19, a fan 22, an ultraviolet lamp 23, a walking trolley 25, a first winch 28 and a second winch 29.

The working principle and the process of the invention are as follows:

placing the sample on the sample rack of the carrier 8 and on the converting table 31; the control cabinet 4 controls the walking trolley 25 to move to a position corresponding to the first sample box 2 or the second sample box 3, and the corresponding box cover 6 is moved to other specified positions of the fixed frame 1 by using the telescopic mechanical arm; then controlling the walking trolley 25 to move to a position right above the conversion table 31, and placing the sample by using the telescopic mechanical arm; controlling the first winch 28 and the second winch 39 to synchronously perform rope releasing action, and automatically extending the telescopic sleeve 26 downwards under the action of the gravity of the U-shaped claw 27; the rope collecting operation is stopped after the U-shaped claw 27 moves to the designated position, then the first winch 28 preferentially performs the rope collecting action, at the moment, the first winch 28 drives the swinging tooth 30 to swing, the swinging tooth 30 forms a lifting shape for the sample net rack of the carrier 8, then the first winch 28 and the second winch 39 synchronously perform the rope collecting action, the extraction operation of the sample net rack is realized, and the rope collecting action is stopped after the sample net rack is lifted to the designated position; according to the test requirements, the walking trolley 25 drives the sample net rack to move transversely to the position corresponding to the first sample box 2 or the second sample box 3; when the sample net rack is placed, the first winch 28 and the second winch 39 synchronously perform rope releasing action, after the sample net rack is placed on the support, the second winch 39 stops acting, the first winch 28 continues to release the rope for a certain time, the swinging teeth 30 automatically droop under the action of gravity, and the lifting operation of the sample net rack is removed; after the sample net rack is placed, the first winch 28 and the second winch 39 synchronously perform rope winding action, other sample net racks are continuously operated under the control of the control cabinet 4, the box cover 6 is buckled on the box body 5 after the sample placement is completed, and the walking trolley 25 moves to a specified position; the control principle of the telescopic mechanical arm on the box cover 6 is the same as that of the sample net rack.

When a dry-wet cycle test is required, placing a sample in a first sample box 2; the control cabinet 4 controls the heating device to heat and dry, and the heating device is electrically heated, so that higher temperature can be obtained; the control cabinet 4 controls the water pump 14 and the electric three-way valve 17 to act, water in the water tank 13 is sprayed onto the sample through the spray head 15, so that the sample is in a soaking or wetting state to meet the requirement of dry-wet circulation, the electric valve 18 is matched to finish water storage and drainage operation inside the first sample box 2 under the control of the control cabinet 4, and the electric valve 18 is also used for heat preservation or exhaust; the water discharged from the first sample box 2 enters the water collecting tank 16; the water pump 14 and the electric three-way valve 17 are controlled to act, and water in the water collecting tank 16 can be supplemented into the water tank 13, so that circulating water is used; the temperature and humidity sensor 9 detects the temperature and humidity and feeds the temperature and humidity back to the PLC of the control cabinet 4, and then the heating device and the water pump 14 are regulated and controlled. When a freeze-thaw cycle test is carried out, the compressor 19 is controlled to start, and the first sample box 2 is cooled by using the evaporator coil, so that the cooling mode is favorable for obtaining lower test temperature; melting the sample by using a heating device; in the refrigeration process of the compressor 19, the condenser coil 20 radiates heat in an aligned manner, so that the front control cabinet 4 moves the case cover 6 on the second sample case 3 to a specified position by using the telescopic mechanical arm before refrigeration, and the fan 22 sucks away high temperature in the second sample case 3 and discharges the high temperature to the outside in the refrigeration process. When thermo-oxidative aging is carried out, a sample can be placed in the second sample box 3, the compressor 19 is used for heating during heating operation, the condenser coil 20 dissipates heat to realize temperature rise, the temperature sensor 10 detects the temperature in the second sample box 3 and feeds the temperature back to the electric control cabinet 4, and the electric control cabinet 4 controls the compressor 19 and the fan 22 to realize temperature regulation; when the temperature of the second sample case 3 rises, the case cover 6 of the first sample case 2 should be moved to a predetermined position, and the first sample case 2 should be opened. When ultraviolet ray aging is performed, the control cabinet 4 adjusts the ultraviolet lamp 23.

Claims

1. Asphalt and mixture accelerated aging evolution test equipment under simulated western conditions is characterized by comprising:

the fixing frame (1) is integrally of a cubic frame structure;

the sample transferring system is arranged on the fixing frame (1);

the dry-wet/freeze-thaw test system comprises a first sample box (2) arranged on a fixed frame (1), and a heating device, a refrigerating system and a spraying system which are arranged on the fixed frame (1) and respectively act on the first sample box (2);

the ultraviolet aging test system comprises a second sample box (3) and an ultraviolet irradiation device; the refrigerating system is also connected with a second sample box (3); and

and the control cabinet (4) is electrically connected with the dry-wet/freeze-thaw test system, the ultraviolet aging test system and the sample transfer system respectively.

2. The test equipment for simulating accelerated aging evolution of asphalt and mixture under western conditions according to claim 1, wherein the first sample box (2) and the second sample box (3) comprise a box body (5) and a box cover (6) fastened on the top of the box body (5), the outer wall of the box body (5) is provided with a heat-insulating layer (7), a plurality of layers of carriers (8) are longitudinally arranged inside the box body (5), a temperature and humidity sensor (9) is arranged in the box body (5) in the first sample box (2), a temperature sensor (10) is arranged in the box body (5) in the second sample box (3), and the temperature and humidity sensor (9) and the temperature sensor (10) are respectively and electrically connected with the control cabinet (4).

3. The test equipment for simulating accelerated aging evolution of asphalt and mixture under western conditions as claimed in claim 2, wherein the heating device comprises a connecting seat (11) arranged on the outer wall of the box body (5), and a heating pipe (12) which is arranged on the connecting seat (11), extends into the box body and is spirally arranged, and the connecting seat (11) is electrically connected with the control cabinet (4).

4. The accelerated aging evolution test equipment for asphalt and mixture under the simulated western conditions according to claim 2, wherein the spraying system comprises a water tank (13) arranged on the fixing frame (1), a water pump (14) connected with the water tank (13), a plurality of nozzles (15) arranged inside the box body (5) and longitudinally distributed, a water collecting tank (16) arranged at the bottom of the box body (5), and an electric three-way valve (17) simultaneously connected with the water pump (14), the nozzles (15) and the water collecting tank (16) through pipelines; an electric valve (18) is arranged at the bottom of the box body (5), and the outlet of the electric valve (18) is communicated with the water collecting tank (16).

5. The accelerated evolution test equipment for the ageing of asphalt and mix under simulated western conditions according to claim 2, characterized in that said refrigeration system comprises a compressor (19) arranged on said mounting (1), a condenser coil (20) connected to said compressor (19), an evaporator coil (21) connected to said compressor (19), a fan (22) arranged on said mounting (1); evaporator coil pipe (21) are established on box (5) of first sample case, condenser coil pipe (20) are established on box (5) of second sample case, compressor (19) are connected with electric control cabinet (4) electricity, fan (22) communicate with box (5) of second sample case.

6. The accelerated aging evolution test equipment for asphalt and mixture materials under simulated western conditions as claimed in claim 5, wherein said ultraviolet irradiation device comprises an ultraviolet lamp (23) disposed in the second sample box body (5) and electrically connected to the control cabinet (4), said ultraviolet lamp (23) being longitudinally arranged in plurality.

7. The accelerated aging evolution test equipment for asphalt and mixture materials under the simulated western conditions as claimed in claim 5, wherein the sample transfer system comprises a parallel guide rail (24) arranged at the top of the fixed frame (1), a walking trolley (25) matched with the parallel guide rail (24), and a telescopic mechanical arm arranged on the walking trolley (25) and longitudinally arranged, and the walking trolley (25) and the telescopic mechanical arm are electrically connected with the control cabinet (4).

8. The accelerated aging evolution test equipment for asphalt and mixture materials under simulated western conditions as claimed in claim 7, wherein said telescopic mechanical arm comprises a telescopic sleeve (26) arranged on the walking trolley (25), a U-shaped claw (27) arranged at the lower end of the telescopic sleeve (26), and a first hoist (28) and a second hoist (29) arranged on the walking trolley (25); the free end of the U-shaped claw (27) is hinged with a swinging tooth (30), one end of a rope of the first winch (28) is connected with the swinging tooth (30), one end of a rope of the second winch (29) is connected with the U-shaped claw (27), and the first winch (28) and the second winch (29) are respectively and electrically connected with the control cabinet (4).

9. The test equipment for simulating accelerated ageing evolution of asphalt and mixture under western conditions as claimed in claim 7, wherein a conversion table (31) is arranged between the parallel guide rails (24) on the top of the fixed frame (1).