Aging test device for simulating real asphalt concrete pavement and test method thereof

Abstract

The invention discloses an aging test device and method for simulating a real asphalt concrete pavement, and the device comprises a simulation chamber which is a sealed chamber; the rotating mechanism drives the bracket to rotate; a water oxygen pipe group; according to the device, the asphalt concrete track plate test piece can face the ultraviolet lamp at different angles and different rotating speeds under the working conditions of different set temperatures, humidity, wind speeds and the like, and the change of irradiation angles of the sun of asphalt concrete pavements with different longitudinal slopes in four seasons of spring, summer, autumn and winter can be accurately simulated; therefore, the aging performance of the asphalt concrete pavement under the real natural environment service condition is accurately simulated, the test of multiple groups and types of asphalt mixture test pieces under the same simulation environment is ensured, the test accuracy is improved, and the test error is reduced; the support on test detection equipment is provided for really realizing the integrated design of the material and the structure of the asphalt concrete pavement. From the perspective of the testing device and the testing method, the comprehensiveness and the accuracy of the indoor test are improved.

Description

Technical Field

[0001] The present invention is an aging test device for simulating a real asphalt concrete pavement and its test method, belonging to the field of... Background Art

[0002] In the prior art, for the aging test of asphalt, the natural aging method or the laboratory accelerated aging method is usually adopted.

[0003] However, these methods have obvious limitations. The natural aging method takes a long time and is restricted by conditions such as region and season, and cannot provide consistent test results. While the laboratory accelerated aging method can shorten the test cycle, it often can only simulate one or a few aging factors, such as light or humidity, lacking comprehensiveness and authenticity. Therefore, a test method that can more comprehensively and accurately simulate the aging process of asphalt concrete pavement in a real environment is needed. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide an aging test device for simulating a real asphalt concrete pavement and its test method to solve the problems.

[0005] To achieve the above purpose, the present invention is realized by the following technical solutions: An aging test device for simulating a real asphalt concrete pavement and its test method, including:

[0006] A simulation chamber, which is a sealed chamber;

[0007] A bracket, located inside the simulation chamber; the bracket forms a fence-shaped ellipsoid relying on several bracket arms;

[0008] A rotating mechanism, driving the bracket to rotate;

[0009] An ultraviolet lamp, located inside the bracket;

[0010] A lifting mechanism, changing the distance between the ultraviolet lamp and the bracket;

[0011] There are several plate racks, and each plate rack is respectively installed with a rutting plate for testing; the plate racks are slidably installed on the bracket arms and make the rutting plates face the ultraviolet lamp.

[0012] A water and oxygen pipe group, connected to the simulation chamber; the water and oxygen pipe group includes an oxygen inlet pipe for transporting oxygen, an exhaust passage for controlling the exhaust air speed, a water inlet pipe for accessing water mist, and a drainage passage for controlling the humidity.

[0013] Preferably, the bracket is vertically arranged.

[0014] Preferably, a groove for placing the rut board is provided on the front surface of the board frame; a collar that slides on the support arm is provided on the back surface of the board frame, and a screw is threadedly connected to the collar, and the board frame is fixedly connected to the support arm by using the screw.

[0015] Preferably, the bottom of the support is in a hollow shape, and a base for placing the rotating mechanism and the lifting mechanism is provided at the hollow part.

[0016] Preferably, the rotating mechanism includes a motor acting on the support, and the rotating end of the motor is connected to the vertex of the support.

[0017] Preferably, the lifting mechanism includes a cylinder acting on the ultraviolet lamp, and the telescopic end of the cylinder is connected to the ultraviolet lamp.

[0018] Preferably, an exhaust fan for adjusting the wind speed is provided on the exhaust passage; a sensor for monitoring the humidity of the simulation chamber is installed on the drainage passage.

[0019] An aging test method for simulating a real asphalt concrete pavement includes the following steps:

[0020] Step 1: Install several groups of rut boards of the same type or different types to be tested on each board frame, and rely on the support to make the rut boards face the ultraviolet lamp at multiple angles;

[0021] Step 2: Introduce oxygen and water mist to simulate the external environment; and change the oxygen content and water content of the simulated environment through the exhaust passage and the drainage passage to simulate the performance of the rut board under different water-oxygen environments; introduce oxygen and water mist at different pressures to simulate natural aging and accelerated aging under the external environment;

[0022] Step 3: Rely on the rotating mechanism to rotate the support, and the rut board that follows the rotation interacts with the surrounding environment to generate an air flow effect to simulate the performance of the rut board under different wind speeds;

[0023] Step 4: Rely on the lifting mechanism to drive the ultraviolet lamp to rise and fall, so as to change the positional relationship and angular relationship between the rut board on the support and the ultraviolet lamp to simulate the performance of the rut board under different irradiation ranges and angles.

[0024] The aging test device may further include a temperature control component, and the temperature control component includes a heating element, a refrigeration element, and a temperature sensor; the controller is further used to control the heating element and the refrigeration element to work according to a set day-night temperature curve; the day-night temperature curve can adjust the temperature change curve in the simulation chamber according to the day-night temperature difference data of the actual use area to more realistically reflect the actual environment.

[0025] Beneficial effects

[0026] Through the settings of a sealed simulation chamber, an adjustable water and oxygen pipe group, and an ultraviolet lamp, the present invention can highly simulate the aging process of a real asphalt concrete pavement under different oxygen contents, water contents, and lighting conditions, ensuring the tests of multiple groups and multiple types of asphalt mixture specimens in the same simulation environment, improving the accuracy of the tests, reducing the test errors, and providing a more accurate and reliable testing method for materials science research;

[0027] The design of the fence-shaped ellipsoid of the bracket and the sliding installation of the plate frame enable the rutting plate to face the ultraviolet lamp at multiple angles, thereby comprehensively testing the aging performance of the material under different irradiation ranges and angles, and improving the comprehensiveness and accuracy of the test;

[0028] The introduction of the rotating mechanism enables the bracket to rotate self - sufficiently. During the rotation process, the rutting plate interacts with the surrounding environment to generate an air flow effect, simulating the aging environment under different wind speeds, and further enhancing the practicability of the testing device;

[0029] The design of the lifting mechanism enables the height of the ultraviolet lamp or the bracket to be adjustable, so as to flexibly change the positional and angular relationships between the rutting plate and the ultraviolet lamp, meeting the aging test requirements under different irradiation conditions; enabling the asphalt concrete rutting plate specimens to face the ultraviolet lamp at different angles and different rotation speeds under different set temperatures, humidities, wind speeds, etc., and accurately simulating the changes in the solar irradiation angles of the asphalt concrete pavement with different longitudinal slopes in spring, summer, autumn, and winter; thereby accurately simulating the aging performance of the asphalt concrete pavement under the service conditions of the real natural environment and testing and collecting data, providing support for the experimental testing equipment for the integrated design of the materials and structures of the asphalt concrete pavement, and improving the comprehensiveness and accuracy of indoor test from the perspectives of the testing device and testing method. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] By reading the following detailed description of the non - restrictive embodiments with reference to the accompanying drawings, other features, purposes, and advantages of the present invention will become more obvious:

[0031] Figure 1 It is a schematic structural diagram of an aging testing device for simulating a real asphalt concrete pavement of the present invention;

[0032] Figure 2 It is a schematic structural diagram of the bracket of the present invention;

[0033] Figure 3 It is a front - view schematic structural diagram of the plate frame of the present invention;

[0034] Figure 4 It is a back - view schematic structural diagram of the plate frame of the present invention;

[0035] Figure 5 This is a schematic structural diagram of Embodiment 2 of the present invention. Detailed implementation manners

[0036] To make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific implementation manners.

[0037] Please refer to Figures 1-4 , the present invention provides an aging test device for simulating a real asphalt concrete pavement: its structure includes:

[0038] A simulation chamber 1, which is a sealed chamber;

[0039] A bracket 2, located inside the simulation chamber 1; the bracket 2 forms a fence-shaped ellipsoid relying on a number of bracket arms 21;

[0040] A rotating mechanism 3, driving the bracket 2 to rotate self - sufficiently. Generally, it is difficult for a blower to simulate the state of strong wind erosion for a long time, and it is even more difficult to simulate a windy day; in this case, through the rotating mechanism 3, it can rotate rapidly for a long time to simulate the erosion of strong wind, and even can simulate the erosion of typhoon or super typhoon;

[0041] An ultraviolet lamp 4, located inside the bracket 2;

[0042] A lifting mechanism 5, changing the position between the ultraviolet lamp 4 and the bracket 2;

[0043] There are a number of plate frames 6, and each plate frame 6 is respectively installed with a rutting plate 9 for testing; the plate frame 6 is slidably installed on the bracket arm 21 and makes the rutting plate 9 face the ultraviolet lamp 4.

[0044] A water - oxygen pipe group, connected to the simulation chamber 1; the water - oxygen pipe group includes an oxygen inlet pipe 71 for transporting oxygen, an exhaust passage 72 for controlling the exhaust wind speed, a water inlet pipe 73 for accessing water mist, a drainage passage 74 for controlling humidity; and

[0045] A controller, respectively connected to the rotating mechanism 3, the ultraviolet lamp 4 and the water - oxygen pipe group.

[0046] As a further improvement, the water inlet pipe 73 can be connected to a salt spray system that simulates the seaside environment. The salt spray system can be an aqueous solution of high-purity sodium chloride (NaCl), usually a sodium chloride aqueous solution with a concentration of 3% - 5% (mass percentage). As a further improvement, the nozzle can be made of a nickel-based alloy (such as Inconel 625, which contains approximately 22% chromium, 9% molybdenum, and 55% nickel, providing extremely high corrosion resistance), and it exhibits excellent corrosion resistance in extreme corrosion environments, especially in high-temperature and high-chloride environments.

[0047] As a further improvement, the aging test device can further include a pressure component and a temperature control component. The temperature control component includes a heating element, a refrigeration element, a temperature sensor, and a gas pressure sensor. The controller is further configured to control the heating element and the refrigeration element to operate according to a set day-night temperature curve. The day-night temperature curve can adjust the temperature change curve in the simulation chamber based on the day-night temperature difference data of the actual usage area. Under normal atmospheric pressure, it can more realistically simulate the natural aging of the actual environment. Under increased atmospheric pressure, it can simulate the accelerated aging of the actual environment.

[0048] Considering the thermal inertia of the actual road surface, it is necessary to calculate a reasonable cooling rate based on the thermal conductivity and specific heat capacity of the asphalt concrete and apply it to the simulation program.

[0049] Specifically: The rate of temperature change of an object is proportional to the difference between the object's temperature and the ambient temperature and satisfies the following differential equation:

[0050]

[0051] where α is a constant related to the thermal conductivity, specific heat capacity, density, and surface area of the asphalt concrete, defined as:

[0052]

[0053] The above differential equation is transformed into an exponential decay function as:

[0054] T(t) = T env +(T 0 -T env )e -αt

[0055] T(t) is the temperature of the asphalt concrete at time t, T env is the ambient temperature, T 0 is the initial temperature of the asphalt concrete (e.g., the highest temperature during the day), k is the thermal conductivity of the asphalt concrete, c is the specific heat capacity of the asphalt concrete, p is the density of the asphalt concrete, A is the surface area of the asphalt concrete, and V is the volume of the asphalt concrete.

[0056] For example, taking the thermal conductivity k = 1.0 W / (m·K), specific heat capacity c = 1000 J / (kg·K), and density ρ = 2200 kg / m 3 , surface area A = 1 m 2 , volume V = 0.1 m 3 , and the highest daytime temperature T 0 = 35 °C and the lowest nighttime temperature T env = 10 °C as an example, the computer illustration is as follows:

[0057] First, calculate α:

[0058]

[0059] Then, solve the differential equation to obtain the function of temperature varying with time:

[0060] T(t) = 10 + (35 - 10)e- 0.00004545t = 10 + 25e -0.00004545t

[0061] This function describes the process of the asphalt concrete gradually cooling from 35 °C to 10 °C at night.

[0062] Example 1

[0063] An aging test method for simulating a real asphalt concrete pavement, comprising the following steps:

[0064] Step 1: Install a plurality of rutting plates 9 of the same asphalt mixture type or different asphalt mixture types to be tested on respective plate racks 6, and rely on the support 2 to make the rutting plates 9 face the ultraviolet lamp 4 at multiple angles;

[0065] The support 2 is vertically arranged. A groove 61 for placing the rutting plate 9 is provided on the front surface of the plate rack 6; a collar 62 that slides on the support arm 21 is provided on the back surface of the plate rack 6, and a screw 63 is threadedly connected to the collar 62. The plate rack 6 is fixedly connected to the support arm 21 by using the screw 63; the bottom of the support 2 is in a hollow shape, and a base 8 for placing the rotating mechanism 3 and the lifting mechanism 5 is provided at the hollow part.

[0066] Among them, the rutting plate 9 can be 600mm in length, 600mm in width, and 50mm in thickness, and can be AC asphalt mixture, AK asphalt mixture, SMA asphalt mixture, PM asphalt mixture, SBS modified asphalt mixture, waste rubber tire modified asphalt mixture, waste rubber tire and plastic modified asphalt mixture, polyurethane asphalt mixture, etc., ensuring the tests of multiple groups and multiple types of asphalt mixture specimens under the same simulated environment, improving the accuracy of the tests and reducing the test errors. Preferably, the rutting plates 9 of the same material can be separately installed on each support arm 21, and several rutting plates 9 are installed at different positions on a single support arm 21, so that the rutting plates 9 of a single material face the central ultraviolet lamp 4 at multiple angles.

[0067] Step 2: Introduce oxygen and water mist at different pressures to simulate natural aging and accelerated aging in the external environment; and change the oxygen content and water content of the simulated environment through the exhaust channel 72 and the drainage channel 74 to simulate the performance of the rutting plate 9 under different water-oxygen environments.

[0068] An exhaust fan for adjusting the wind speed is provided on the exhaust channel 72; a sensor for monitoring the humidity of the simulation chamber 1 is installed on the drainage channel 74.

[0069] Furthermore, an existing oxygen concentration monitoring sensor is provided in the simulation chamber 1 to monitor the oxygen content in the simulator; based on the oxygen and water mist introduced by the water-oxygen pipe group, the oxygen content and water content in different regions are replicated according to the monitoring requirements to achieve the purpose of simulating the usage environments in different regions.

[0070] Step 3: Rely on the rotating mechanism 3 to rotate the support 2, and the rutting plate 9 that rotates along with it interacts with the surrounding environment to generate an air flow effect, so as to simulate the performance of the rutting plate 9 under different wind speeds.

[0071] The rotating mechanism 3 includes a motor acting on the support 2, and the rotating end of the motor is connected to the vertex of the support 2.

[0072] Furthermore, use the rotating mechanism 3 to rotate the rutting plate 9, so that the rutting plate 9 in the simulation chamber 1 can feel the flowing wind. At the same time, rotate the support 2 so that each rutting plate 9 can come into contact with the flowing wind; and based on the shape of the support 2, the flowing wind speeds felt by the rutting plates 9 at different installation positions are different, simulating environments with multiple flowing wind speeds.

[0073] Step 4: Rely on the lifting mechanism 5 to drive the ultraviolet lamp 4 to lift, so as to change the positional relationship and angular relationship between the rutting plate 9 on the support 2 and the ultraviolet lamp 4, so as to simulate the performance of the rutting plate 9 under different irradiation ranges and angles.

[0074] The lifting mechanism 5 includes a cylinder acting on the ultraviolet lamp 4, and the telescopic end of the cylinder is connected to the ultraviolet lamp 4;

[0075] Through the operation of the lifting mechanism 5, the distance between the rut board 9 and the ultraviolet lamp 4 is changed, thereby simulating the performance of the rut board 9 under different irradiation ranges and angles.

[0076] Embodiment 2

[0077] Refer to Figure 5 , different from Embodiment 1; the lifting mechanism 5 includes a cylinder acting on the bracket 2, and the telescopic end of the cylinder is connected to the bracket 2;

[0078] In Step 4, rely on the lifting mechanism 5 to drive the bracket 2 to lift, so that the positional relationship and angular relationship between the rut board 9 on the bracket 2 and the ultraviolet lamp 4 are changed, so as to simulate the performance of the rut board 9 under different irradiation ranges and angles.

[0079] The foregoing has shown and described the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, in any regard, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes within the meaning and scope of the equivalent elements of the claims in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0080] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An aging test device simulating a real asphalt concrete pavement, characterized in that: include: The simulation chamber is a sealed chamber; A bracket, located in the simulation chamber; The support relies on a plurality of support arms to form a fence-shaped ellipsoid; A rotating mechanism drives the bracket to rotate; An ultraviolet lamp is located inside the bracket; A lifting mechanism for changing the distance between the ultraviolet lamp and the bracket; There are several plate racks, each of which is equipped with a rutting plate for testing; the plate racks are slidably installed on the support arms, and the rutting plates are facing the ultraviolet lamps. A water-oxygen pipe group is connected to the simulation chamber; the water-oxygen pipe group includes an oxygen inlet pipe for conveying oxygen, an exhaust channel for controlling the exhaust wind speed, a water inlet pipe for receiving water mist, and a drainage channel for controlling humidity.

2. The aging test device for simulating a real asphalt concrete pavement according to claim 1 is characterized in that: The bracket is arranged vertically.

3. The aging test device for simulating a real asphalt concrete pavement according to claim 1 is characterized in that: The front of the plate frame is provided with a groove for placing the rutting plate; the back of the plate frame is provided with a ring that slides on the bracket arm, and the ring is threaded with a screw, and the plate frame is fixedly connected to the bracket arm by using the screw.

4. The aging test device for simulating a real asphalt concrete pavement according to claim 1 is characterized in that: The bottom of the bracket is hollowed out, and a base for placing the rotating mechanism and the lifting mechanism is arranged at the hollowed out portion.

5. The aging test device for simulating a real asphalt concrete pavement according to claim 4, characterized in that: The rotating mechanism comprises a motor acting on the bracket, and a rotating end of the motor is connected to the vertex of the bracket.

6. The aging test device for simulating a real asphalt concrete pavement according to claim 4, characterized in that: The lifting mechanism comprises a cylinder acting on the ultraviolet lamp, and the telescopic end of the cylinder is connected to the ultraviolet lamp.

7. The aging test device for simulating a real asphalt concrete pavement according to claim 1, characterized in that: The exhaust channel is provided with an exhaust fan for adjusting wind speed; the drainage channel is installed with a sensor for monitoring the humidity of the simulation chamber.

8. A method for simulating the aging of a real asphalt concrete pavement, characterized in that: The following steps are involved: Step 1: Install several groups of asphalt mixture rutting plates of the same or different types to be tested on various plate racks, and use the racks to make the rutting plates face the UV lamps at multiple angles; Step 2: introducing oxygen and water mist to simulate the external environment; changing the oxygen content and water content of the simulated environment through the exhaust channel and the drainage channel to simulate the performance of the rutting plate in different water and oxygen environments; introducing pressure-controlled oxygen and water mist to simulate natural aging in the external environment and accelerated aging indoors; Step 3: Relying on the rotating mechanism to rotate the bracket, the rotating rutting plate rotates and interacts with the surrounding environment to generate an airflow effect, so as to simulate the performance of the rutting plate under different wind speeds; Step 4: Use the lifting mechanism to lift the UV lamp, so that the position and angle relationship between the rutting plate on the bracket and the UV lamp can be changed to simulate the performance of the rutting plate under different irradiation ranges and angles.

9. The aging test device for simulating a real asphalt concrete pavement according to claim 8, characterized in that: The aging test device may further include a temperature control component, which includes a heating element, a cooling element, and a temperature sensor; the controller is further used to control the heating element and the cooling element to work according to a set day and night temperature curve; the day and night temperature curve can adjust the temperature change curve in the simulated room according to the day and night temperature difference data of the actual use area to more realistically reflect the actual environment.

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