Method for testing temperature transfer heat absorption rate of transition layer in asphalt road

Abstract

The invention discloses a method for testing the temperature transfer heat absorption rate of a transition layer in an asphalt road, and relates to the technical field of road detection, and the method comprises the following steps: preparing a transition layer material in a roadbed into a sample according to a specified size, putting the sample into a temperature box, and arranging a temperature sensor in the sample, therefore, the temperature and related data in the sample are collected, and the collected temperature and related data are processed, so that the temperature transfer heat absorption rate of the transition layer is obtained. Determining monitoring points: determining a plurality of monitoring points according to a sample structure and experiment requirements; specifically, a surface layer, a middle layer and a bottom layer of a roadbed transition layer sample are selected as monitoring points to comprehensively reflect the temperature change condition of the transition layer; and sensor installation: a temperature sensor is vertically and downwards installed at each monitoring point, the installation depth of the sensors is determined according to experimental requirements, and the sensors can be arranged at positions of 0.5 m, 1 m and 1.5 m. The method is simple to operate, and the heat absorption characteristic of the transition layer can be conveniently researched and analyzed.

Description

Technical Field

[0001] The invention relates to the technical field of road detection, and in particular to a method for testing the temperature transfer and heat absorption rate of a transition layer in an asphalt road. Background Art

[0002] In current road projects, the temperature change of the roadbed has an important impact on the stability and life of the roadbed. Temperature changes will cause the expansion and contraction of the material, which will cause uneven settlement and cracking of the roadbed. Therefore, studying the temperature transfer and heat absorption characteristics of the transition layer in the roadbed is of great significance for optimizing the roadbed structure design and improving the service life of the road.

[0003] At present, the existing testing methods mostly focus on monitoring the surface temperature, ignoring the temperature change of the transition layer. In addition, the existing methods often have problems such as inaccurate data and complex operations during the testing process. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide a method for testing the temperature transfer and heat absorption rate of the transition layer in an asphalt road, which is simple to operate and can accurately study the temperature transfer and heat absorption characteristics of the transition layer in the roadbed.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] A method for testing the temperature transfer heat absorption rate of a transition layer in an asphalt road comprises the following steps:

[0007] S1. Prepare the transition layer material in the roadbed into samples according to the specified size and place the samples in a temperature box;

[0008] S2. Arrange a temperature sensor in the sample to collect the temperature and related data in the sample;

[0009] S3. Process the collected temperature and related data to obtain the transition layer temperature transfer heat absorption rate.

[0010] Further, arranging the temperature sensor in the sample in step S2 includes the following steps:

[0011] Determine monitoring points: Determine multiple monitoring points based on the sample structure and experimental requirements; specifically select the surface, middle and bottom layers of the roadbed transition layer sample as monitoring points to fully reflect the temperature changes of the transition layer;

[0012] Sensor installation: At each monitoring point, install the temperature sensor vertically downward. The installation depth of the sensor is determined according to the experimental requirements and can be arranged at 0.5m, 1m and 1.5m;

[0013] Fix the sensor: After the sensor is installed, it needs to be fixed to ensure that it does not move during the test; use a clamp that is suitable for it to fix it.

[0014] Furthermore, collecting the temperature and related data in the roadbed in step S2 includes the following steps:

[0015] Start the data acquisition system: After all sensors are installed, start the data acquisition system and start collecting temperature data;

[0016] Set the acquisition frequency: Set the data acquisition frequency according to the experimental requirements to obtain a more detailed temperature change curve;

[0017] Record environmental parameters: Also record the ambient temperature and humidity during the experiment for subsequent data analysis.

[0018] Furthermore, processing the temperature and related data in step S3 includes the following steps:

[0019] Data screening: Preliminary screening of the collected temperature data to eliminate obvious abnormal data;

[0020] Temperature gradient calculation: Calculate the temperature gradient based on the temperature data at different depths. The temperature gradient calculation formula is:

[0021]

[0022] Among them, T i is the temperature at the ith depth, d i is the i-th depth;

[0023] Heat flux calculation: Calculate the heat flux based on the temperature gradient and the thermal conductivity of the material. The heat flux calculation formula is:

[0024]

[0025] Where k is the thermal conductivity of the material;

[0026] According to the experimental data, the heat conduction equation is solved by numerical method to obtain the temperature change over time; the heat conduction equation is:

[0027] Where α is the thermal diffusivity of the material;

[0028] Combining the temperature gradient and heat flux density, the heat absorption rate of the material is calculated. The calculation formula for the heat absorption rate is:

[0029] Where ΔT is the temperature change.

[0030] Furthermore, a bracket is provided in the temperature box, and the sample is placed on the bracket.

[0031] Furthermore, the size of the sample is 10cm x 10cm x 10cm.

[0032] Furthermore, the temperature in the temperature box ranges from -20°C to 75°C.

[0033] Furthermore, the temperature and related data in the sample are collected once every 30 seconds.

[0034] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0035] In actual work, the sample is placed in a temperature box and the appropriate temperature is adjusted. Then, the temperature and other data on the sample are collected through the sensor on the sample. Finally, the heat absorption rate of the sample is calculated based on this data information, so as to study and analyze the temperature transfer and heat absorption characteristics of the transition layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with test examples and specific implementation methods. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0038] This embodiment provides a method for testing the temperature transfer heat absorption rate of the transition layer in an asphalt road. Figure 1 As shown, the following steps are included:

[0039] S1. Prepare the transition layer material in the roadbed into samples according to the specified size and place the samples in a temperature box;

[0040] S2. Arrange a temperature sensor in the sample to collect the temperature and related data in the sample;

[0041] S3. Process the collected temperature and related data to obtain the transition layer temperature transfer heat absorption rate.

[0042] Further optimizing the above embodiment, arranging the temperature sensor in the sample in step S2 includes the following steps:

[0043] Determine monitoring points: Determine multiple monitoring points based on the sample structure and experimental requirements; specifically select the surface, middle and bottom layers of the roadbed transition layer sample as monitoring points to fully reflect the temperature changes of the transition layer;

[0044] Sensor installation: At each monitoring point, install the temperature sensor vertically downward. The installation depth of the sensor is determined according to the experimental requirements and can be arranged at 0.5m, 1m and 1.5m;

[0045] The specimens should be reserved for curing period. Non-modified asphalt mixtures should be placed for 2d to 3d; modified asphalt mixtures should be placed for 3d to 5d. High-viscosity modified asphalt mixtures should be placed for 5d to 10d. High-polymer modified asphalt mixtures should be placed for 10d to 15d. The specimens after curing should be placed in a test chamber at a specified temperature. The test temperature is the highest temperature in the project location in 20 years minus 5°C. Turn on the setting parameters, and test the temperature difference between the heating zone and the low temperature zone after 1h of low temperature constant temperature. The low temperature zone is ventilated at 20 degrees for 1h. The heating zone and the low temperature zone both reach 20℃±2℃. After the low temperature zone is turned on for 1h, the temperature difference is tested according to the principle of the high temperature zone. 120 cycles of testing represent the thermal insulation efficiency of the transition layer.

[0046] In actual operation, the sample is placed in a temperature box and the appropriate temperature is adjusted. Then, the temperature and other data on the sample are collected through the sensor on the sample. Finally, the heat absorption rate of the sample is calculated based on this data information.

[0047] Fix the sensor: After the sensor is installed, it needs to be fixed to ensure that it does not move during the test; use a clamp that is suitable for it to fix it.

[0048] The above embodiment is further optimized, and the temperature and related data in the roadbed are collected in step S2, including the following steps:

[0049] Start the data acquisition system: After all sensors are installed, start the data acquisition system and start collecting temperature data;

[0050] Set the data collection frequency: Set the data collection frequency according to the experimental requirements. You can collect data once every hour to obtain a more detailed temperature change curve.

[0051] Record environmental parameters: Also record the ambient temperature, humidity, and meteorological conditions during the experiment for subsequent data analysis.

[0052] The above embodiment is further optimized, and the processing of temperature and related data in step S3 includes the following steps:

[0053] Data screening: Preliminary screening of the collected temperature data to eliminate obvious abnormal data;

[0054] Temperature gradient calculation: Calculate the temperature gradient based on the temperature data at different depths. The temperature gradient calculation formula is:

[0055]

[0056] Among them, T i is the temperature at the ith depth, d i is the i-th depth;

[0057] Heat flux calculation: Calculate the heat flux based on the temperature gradient and the thermal conductivity of the material. The heat flux calculation formula is:

[0058]

[0059] Where k is the thermal conductivity of the material;

[0060] According to the experimental data, the heat conduction equation is solved by numerical method to obtain the temperature change over time; the heat conduction equation is:

[0061] Where α is the thermal diffusivity of the material;

[0062] Combining the temperature gradient and heat flux density, the heat absorption rate of the material is calculated. The calculation formula for the heat absorption rate is:

[0063] Where ΔT is the temperature change.

[0064] The above embodiment is further optimized, a bracket is provided in the temperature box, and the sample is placed on the bracket. A bracket for placing the sample is arranged in the temperature box to ensure that the sample can be stably and non-contactly suspended in the center of the temperature box.

[0065] The above embodiment is further optimized, and the size of the sample is 10cm x 10cm x 10cm.

[0066] The above embodiment is further optimized, and the temperature range in the temperature box is -20°C to 75°C.

[0067] The above embodiment is further optimized, and the frequency of collecting the temperature and related data in the sample is once every 30 seconds.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for testing the temperature transfer and heat absorption rate of a transition layer in an asphalt road, characterized in that: The steps include: S1. Prepare the transition layer material in the roadbed into samples according to the specified size and place the samples in a temperature box; S2. Arrange a temperature sensor in the sample to collect the temperature and related data in the sample; S3. Process the collected temperature and related data to obtain the transition layer temperature transfer heat absorption rate.

2. The method for testing the temperature transfer and heat absorption rate of the transition layer in an asphalt road according to claim 1 is characterized in that: Arranging the temperature sensor in the sample in step S2 includes the following steps: Determine monitoring points: Determine multiple monitoring points based on the sample structure and experimental requirements; specifically select the surface, middle and bottom layers of the roadbed transition layer sample as monitoring points to fully reflect the temperature changes of the transition layer; Sensor installation: At each monitoring point, install the temperature sensor vertically downward. The installation depth of the sensor is determined according to the experimental requirements and can be arranged at 0.5m, 1m and 1.5m; Fix the sensor: After the sensor is installed, it needs to be fixed to ensure that it does not move during the test; use a clamp that is suitable for it to fix it.

3. A method for testing the temperature transfer and heat absorption rate of a transition layer in an asphalt road according to claim 2, characterized in that: In step S2, collecting the temperature and related data in the roadbed includes the following steps: Start the data acquisition system: After all sensors are installed, start the data acquisition system and start collecting temperature data; Set the acquisition frequency: Set the data acquisition frequency according to the experimental requirements to obtain a more detailed temperature change curve; Record environmental parameters: Also record the ambient temperature and humidity during the experiment for subsequent data analysis.

4. A method for testing the temperature transfer and heat absorption rate of a transition layer in an asphalt road according to claim 3, characterized in that: Processing the temperature and related data in step S3 includes the following steps: Data screening: Preliminary screening of the collected temperature data to eliminate obvious abnormal data; Temperature gradient calculation: Calculate the temperature gradient based on the temperature data at different depths. The temperature gradient calculation formula is: Among them, T i is the temperature at the ith depth, d i is the i-th depth; Heat flux calculation: Calculate the heat flux based on the temperature gradient and the thermal conductivity of the material. The heat flux calculation formula is: Where k is the thermal conductivity of the material; According to the experimental data, the heat conduction equation is solved by numerical method to obtain the temperature change over time; the heat conduction equation is: Where α is the thermal diffusivity of the material; Combining the temperature gradient and heat flux density, the heat absorption rate of the material is calculated. The calculation formula for the heat absorption rate is: Where ΔT is the temperature change.

5. The method for testing the temperature transfer and heat absorption rate of the transition layer in an asphalt road according to claim 3 is characterized in that: A bracket is arranged in the temperature box, and the sample is placed on the bracket.

6. The method for testing the temperature transfer and heat absorption rate of the transition layer in an asphalt road according to claim 1, characterized in that: The dimensions of the sample were 10 cm x 10 cm x 10 cm.

7. The method for testing the temperature transfer and heat absorption rate of the transition layer in an asphalt road according to claim 1, characterized in that: The temperature in the temperature box ranges from -20°C to 75°C.

8. The method for testing the temperature transfer and heat absorption rate of the transition layer in an asphalt road according to claim 1 is characterized in that: The frequency of collecting the temperature and related data in the sample is once every 30 seconds.

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