Asphalt content test method based on full-automatic asphalt extractor

Abstract

The invention relates to the technical field of road detection, and particularly discloses an asphalt content test method based on a full-automatic asphalt extraction instrument, which comprises the following steps: by setting low-speed operation time at 1200 seconds, increasing cleaning times and simultaneously replacing a new centrifugal cylinder and filter paper, controlling a sample cleaning effect and reducing mineral powder loss, so that the test efficiency is improved. Therefore, the accuracy and reliability of subsequent detection results are ensured, and the step is a special innovation in the detection process. A large number of blank tests find that the separation capacity of a centrifugal cylinder is limited when solid and liquid are separated, when the separation capacity exceeds a certain amount of separation liquid entering a capacity cylinder, the loss is gradually increased, and the test accuracy is difficult to guarantee. Therefore, the mineral powder loss is reduced to the maximum extent by replacing the new centrifugal cylinder and filter paper after cleaning once, and the detection accuracy and effectiveness are practically improved. A more reasonable detection process is provided for subsequent steps by a method for replacing a new centrifugal cylinder and filter paper, and a foundation is laid for smooth proceeding of the whole detection process.

Description

Technical Field

[0001] The invention belongs to the technical field of road detection, and in particular relates to an asphalt content test method based on a full-automatic asphalt extractor. Background Art

[0002] In the field of road engineering, the performance evaluation and quality control of asphalt mixtures are crucial links. Asphalt content is one of the key indicators for evaluating the quality of asphalt mixtures. Its accurate detection is of great significance for ensuring the quality of road construction and extending the service life of roads. In recent years, with the continuous advancement of road engineering technology, the detection method of asphalt content has also experienced a transformation from traditional manual operation to automated and intelligent detection. Asphalt automatic extraction instrument, as a representative of modern road detection technology, has gradually become the mainstream equipment for asphalt content detection with its advantages of high efficiency, accuracy, easy operation and low pollution.

[0003] However, although the asphalt automatic extraction instrument has achieved automation of the detection process to a certain extent, there are many factors that need to be considered in the operation of the equipment, such as the length of cleaning time, the number of cleanings, whether the centrifuge cylinder is replaced, etc. The uncertainty of these factors will make it difficult to ensure the accuracy and stability of the test results, and also increase the detection cost, which is not conducive to the sustainable development of road engineering technology. Therefore, staff need to improve it. Summary of the invention

[0004] The purpose of the present invention is to provide an asphalt content test method based on an asphalt fully automatic extractor to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for testing asphalt content based on an asphalt automatic extraction instrument comprises the following steps:

[0007] S1. Prepare asphalt mixture samples with a mass of 1000 to 1500 g. Select an appropriate sample mass range according to the particle size of the asphalt mixture and ensure that the sample is in a loose state and the temperature is below 100°C.

[0008] S2. Place the filter paper correctly in the centrifuge cylinder of the automatic extractor and weigh the combined mass of the centrifuge cylinder and filter paper (m 1-1 );

[0009] S3, stack the multi-level screens from top to bottom according to their sizes to form a set of screens, and weigh the mass of the set of screens (m2);

[0010] S4. Place the asphalt mixture sample on the top sieve and install the centrifugal cylinder and the sieve on the fully automatic extractor;

[0011] S5. Check whether the amount of trichloroethylene solvent in the automatic extractor is sufficient and ensure that the cooling water flows normally;

[0012] S6. Start the fully automatic extraction instrument for cleaning. After cleaning, let it stand for a while. When there is no leakage in the liquid guide tube, remove the sieve and replace the centrifuge cylinder and filter paper.

[0013] S7. Use a clean glass rod to gently stir the mixture, restart, and clean again. Check the state of the mixture. If there is obvious black asphalt, repeat step S6 until there is no obvious black asphalt;

[0014] S8. When there is no obvious black asphalt, dry the materials in the sieve and centrifuge to constant weight, and weigh the combined mass of the sieve and mineral material (m5) and the combined mass of the centrifuge, filter paper and mineral powder (m 4-n );

[0015] S9. Conduct screening test on the dried ore to determine the quality of ore at each particle size level;

[0016] S10. Calculate the total mass (m) of the mineral aggregate in the asphalt mixture based on the weighing results and the screening test results. a ), and calculate the asphalt content (P b ) and oil-stone ratio (P a ).

[0017] Preferably, in step S5, the amount of trichloroethylene solvent loaded into the fully automatic extractor should reach 2 / 3 of the container capacity to ensure the cleaning effect.

[0018] Preferably, in step S7, the number of repeated cleaning is determined according to the characteristics of the asphalt mixture sample and the cleaning effect, and a new centrifugal cylinder and filter paper are replaced at the same time until there is no obvious black asphalt in the sieve.

[0019] Preferably, in step S8, the material is dried at a temperature of 100±5°C and dried to a constant weight, and 100±5°C ensures that trichloroethylene does not produce toxic chlorine gas during the drying process.

[0020] Preferably, in step S10, the asphalt content (P b ) and oil-stone ratio (P a ) are calculated as follows:

[0021]

[0022]

[0023] Where m0 is the mass of the asphalt mixture sample, m a It is the total mass of aggregate in asphalt mixture.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) By increasing the number of cleanings and replacing the centrifuge cylinder and filter paper at the same time, the loss of mineral powder during centrifugal separation can be effectively controlled. This practice ensures the accuracy and reliability of subsequent test results. This operation is the basis of the test process and is crucial to improving the overall test accuracy. Through a large number of blank tests, we found that the separation capacity of the centrifuge cylinder is limited when separating solids and liquids. When the amount of separated liquid entering the capacity cylinder exceeds a certain amount, the loss will gradually increase, and the accuracy of the test is difficult to guarantee. Therefore, clean once and replace the centrifuge cylinder and filter paper with a new one to minimize the loss of mineral powder and improve the accuracy and effectiveness of the test. The method of replacing the new centrifuge cylinder and filter paper provides a more reasonable test process for the subsequent steps, laying the foundation for the smooth progress of the entire test process.

[0026] (2) By running at a low speed for 1200 seconds and gently turning the mixture with a glass rod after cleaning, the adequacy and timeliness of the cleaning process can be ensured, which can completely remove the asphalt component in the asphalt mixture and provide accurate basic data for subsequent mineral separation and weighing. At the same time, the test time is compressed as much as possible, the detection accuracy and efficiency are improved, and the stability and timeliness of the detection process are ensured.

[0027] (3) Through precise calculation formulas, the asphalt content and asphalt-to-stone ratio can be accurately determined. These two indicators are key parameters for evaluating the performance of asphalt mixtures and are of great significance for road construction and maintenance. By using data based on weighing results and screening tests, the objectivity and accuracy of the calculation results can be ensured, errors caused by human factors can be avoided, and the reliability and credibility of the test results can be improved. This provides a scientific testing basis for road projects, helps optimize the mix ratio and construction process of asphalt mixtures, and improves the quality and durability of roads. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a flow chart of the method of the present invention;

[0029] Figure 2 It is the principle structure diagram of the full-automatic extraction instrument of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Embodiment 1:

[0032] See also Figure 1 and Figure 2 As shown, a method for testing asphalt content based on an asphalt automatic extractor comprises the following steps:

[0033] S1. Prepare asphalt mixture samples with a mass of 1000 to 1500 g. Select an appropriate sample mass range according to the particle size of the asphalt mixture and ensure that the sample is in a loose state and the temperature is below 100°C.

[0034] S2. Place the filter paper correctly in the centrifuge cylinder of the automatic extractor and weigh the combined mass of the centrifuge cylinder and filter paper (m 1-1 );

[0035] S3, stack the multi-level screens from top to bottom according to their sizes to form a set of screens, and weigh the mass of the set of screens (m2);

[0036] S4. Place the asphalt mixture sample on the top sieve and install the centrifugal cylinder and the sieve on the fully automatic extractor;

[0037] S5. Check whether the amount of trichloroethylene solvent in the automatic extractor is sufficient and ensure that the cooling water flows normally;

[0038] S6. Start the fully automatic extraction instrument for cleaning. After cleaning, let it stand for a while. When there is no leakage in the liquid guide tube, remove the sieve and replace the centrifuge cylinder and filter paper.

[0039] S7. Use a clean glass rod to gently stir the mixture, restart, and clean again. Check the state of the mixture. If there is obvious black asphalt, repeat step S6 until there is no obvious black asphalt;

[0040] S8. When there is no obvious black asphalt, dry the materials in the sieve and centrifuge to constant weight, and weigh the combined mass of the sieve and mineral material (m5) and the combined mass of the centrifuge, filter paper and mineral powder (m 4-n );

[0041] S9. Conduct screening test on the dried ore to determine the quality of ore at each particle size level;

[0042] S10. Calculate the total mass (m) of the mineral aggregate in the asphalt mixture based on the weighing results and the screening test results. a ), and calculate the asphalt content (P b ) and oil-stone ratio (P a ).

[0043] In step S1, the preparation of the asphalt mixture sample includes sampling from a truck transporting the material in the mixing plant or sampling after heating the asphalt mixture in an oven to a loose state, and ensuring the representativeness of the sample.

[0044] In step S5, the amount of trichloroethylene solvent loaded into the fully automatic extractor should reach 2 / 3 of the container capacity to ensure the cleaning effect.

[0045] In step S7, the number of repeated cleaning is determined according to the characteristics of the asphalt mixture sample and the cleaning effect. The special feature is that each cleaning requires replacing a new centrifugal cylinder and filter paper and turning the mixture until there is no obvious black asphalt in the sieve.

[0046] In step S8, the material is dried at a temperature of 100±5°C and dried to a constant weight. 100±5°C ensures that trichloroethylene does not produce toxic chlorine gas during the drying process.

[0047] In step S10, the asphalt content (P b ) and oil-stone ratio (P a ) are calculated as follows:

[0048]

[0049] Among them, m0 is the mass of the asphalt mixture sample, m a It is the total mass of aggregate in asphalt mixture.

[0050] The method also includes the steps of conducting at least two parallel tests on the same asphalt mixture sample and taking the average value as the test result, and when the difference between the two test results is greater than 0.3% but less than 0.5%, performing an additional parallel test and taking the average value of the three tests as the final test result.

[0051] Test steps:

[0052] 1. Place a piece of filter paper correctly in the centrifuge cylinder and weigh the combined mass of the centrifuge cylinder and filter paper (m 1-1 ).

[0053] 2. Stack the empty sieve, the first screening net (2.36mm sieve), the second screening net (0.6mm sieve), the third screening net (0.15mm sieve), and the fourth screening net (0.075mm sieve) in this order from top to bottom to form a set of sieves, and weigh the mass of the set of sieves (m2).

[0054] 3. Press the tare button on the balance, take the asphalt mixture in a loose state and place it on a 2.36mm sieve to the sample mass (m0).

[0055] 4. Install the centrifuge cylinder and put the sieve onto the automatic extractor.

[0056] 5. Check whether there is enough trichloroethylene in the extractor (the amount of trichloroethylene filled in 2 / 3 of the container) and whether the cooling water flows normally.

[0057] 6. Turn on the power, cool the water, turn on the exhaust fan, and start the extractor. The extractor will run until the cleaning is completed.

[0058] 7. After the current cleaning is completed, open the spray cover, evacuate personnel, and let it stand for 5 minutes or until there is no leakage in the liquid guide tube.

[0059] 8. Carefully move the entire screen, and no aggregate should fall during the movement.

[0060] 9. Prepare new centrifuge tube and filter paper, weigh the combined mass (m 1-2 ). Take out the current centrifuge cylinder, replace it with a new one and filter paper, reinstall the entire sieve, and gently stir the mixture with a clean glass rod (the glass rod should not stick to the ore after use). Turn on the cooling water, turn on the exhaust fan, start the extractor, and clean it again.

[0061] 10. When the current cleaning is finished, open the spray cover, evacuate personnel, and check the status of the mixture after standing for 5 minutes.

[0062] 11. When there is obvious black asphalt, repeat steps 8 to 10 and continue cleaning until there is no black asphalt.

[0063] 12. When there is no obvious black asphalt:

[0064] (1) Remove the entire sieve, place it on a metal plate, and place it in an oven at 100±5℃ to dry.

[0065] (2) Check whether there is any residue in the conical groove. If there is any residue, clean the conical groove with a brush (do not rinse with water) to allow all the fine mineral powder to flow into the centrifuge cylinder.

[0066] (3) Take out the centrifuge cylinders. Place all the centrifuge cylinders with the opening facing upwards in a 100±5℃ oven to dry.

[0067] (4) Dry to constant weight (about 3-4 hours), cool to room temperature, and weigh the total mass of the sieve and ore (m5), the total mass of the centrifuge, filter paper, and ore powder (m 4-n ).

[0068] 13. Carefully pour out all the ore in the sieve and then conduct a screening test.

[0069] calculate:

[0070] The weight gain of the centrifuge cylinder after the nth (n=1, 2, 3...) cleaning is calculated according to formula (1).

[0071] m 7-n =m 4-n -m 1-n (1)

[0072] Where: m 7-n——The weight gain of the centrifuge cylinder after cleaning for the nth time, g;

[0073] m 1-n ——The total mass of the centrifuge cylinder and filter paper before cleaning for the nth time, g;

[0074] m 4-n ——The total mass of the centrifuge cylinder, filter paper and mineral powder after cleaning for the nth time, g;

[0075] Note: Centrifuge cylinder weight increase m 7-n It is part of the sieve smaller than 0.075 mm.

[0076] The weight gain before and after the sieve test is calculated according to formula (2).

[0077] m8=m5-m2 (2)

[0078] Where: m8——weight gain before and after the sieve test, g;

[0079] m2——mass of clean sieve set before test, g;

[0080] m5——comprehensive mass of screen and ore after the test, g.

[0081] The total mass of mineral aggregate in asphalt mixture is calculated according to formula (3).

[0082] m a =m3+m8+∑m 7-n (3)

[0083] Where: m a ——Total mass of mineral aggregate in asphalt mixture, g;

[0084] m3——mass of mineral powder lost during the rotation of the centrifugal cylinder, g;

[0085] The principle structure diagram of the fully automatic extractor includes: 1. Asphalt mixture sample; 2. Conical trough; 3. Liquid guide tube; 4. Centrifugal cylinder.

[0086] Embodiment 2:

[0087] See also Figure 1 As shown in the figure, sample preparation: directly take samples from the material truck of the mixing plant, ensure the representativeness of the samples, and increase the flexibility of the sampling method.

[0088] Solvent loading amount: Refine the range of solvent loading amount to between 2 / 3 and 3 / 4 of the container capacity to ensure cleaning effect while avoiding waste.

[0089] Drying temperature and conditions: Drying should be carried out in a well-ventilated environment to ensure drying efficiency and safety.

[0090] Calculation formula:

[0091] Objective: Estimate the project completion time (T).

[0092] variable:

[0093] Effort (W): The total amount of work required for a project, usually measured in man-days, man-months or man-years.

[0094] Work efficiency (E): The average amount of work that team members can complete per day, the unit is the same as W.

[0095] Buffer time (B): The additional time added to deal with uncertainty, with the same unit as T.

[0096] Formula: T=(W / E)+B.

[0097] Basic relationship: Project completion time (T) is the ratio of workload (W) to work efficiency (E), that is, T = W / E.

[0098] Consider uncertainty: In actual projects, due to various uncertainties (such as demand changes, insufficient resources, etc.), projects often cannot be completed strictly according to the plan. Therefore, it is necessary to add a certain buffer time (B) on the basis of the basic time (W / E) to cope with these uncertainties.

[0099] Comprehensive formula: Combining the above two factors, we get the final formula: T = (W / E) + B.

[0100] Application Scenario

[0101] Scenario 1: Project Management

[0102] In project management, project managers need to estimate the completion time of a project in order to develop a reasonable project plan and schedule. Using the above formula, project managers can estimate the completion time of a project based on the workload of the project, the work efficiency of team members, and the expected buffer time. This helps project managers better control the progress of the project and ensure that the project is completed on time.

[0103] Scenario 2: Resource Allocation

[0104] With limited resources, the team needs to allocate resources reasonably to ensure the smooth progress of the project. Using the above formula, the team can evaluate which project should be prioritized based on the workload, required resources and expected time of each project, as well as the work efficiency of team members. This helps the team use resources more effectively and improve overall work efficiency.

[0105] Scenario 3: Risk Assessment

[0106] During the project execution, the team may face various risks, such as changes in requirements, insufficient resources, etc. Using the above formula, the team can assess the risk level of the project based on the actual situation of the project and the expected buffer time. If the actual progress of the project lags behind the planned progress, and the remaining buffer time is not enough to make up for the gap, the team may need to take additional measures to deal with the risk, such as increasing resource investment, adjusting the work plan, etc.

[0107] Conclusion: By explaining the derivation process and application scenarios of the calculation formula in detail, we can better understand the source and purpose of the formula, thereby improving the readability and practicality of the method.

[0108] Embodiment three:

[0109] See also Figure 1 As shown, the method is not only applicable to conventional asphalt mixtures, but also widely applicable to special types of asphalt mixtures such as modified asphalt mixtures and recycled asphalt mixtures, so that the method can cope with more diverse road construction needs and improve its practicality and flexibility.

[0110] For modified asphalt mixture, the performance of asphalt is significantly improved due to the addition of modifiers, but it also increases the complexity of detection. By optimizing the steps of cleaning and replacing centrifuge cylinders and filter papers, accurate detection of asphalt content in modified asphalt mixture is ensured.

[0111] For recycled asphalt mixture, since it contains a certain proportion of waste asphalt mixture, its composition is more complex. By adjusting the type and amount of solvent, and optimizing the centrifugation and drying steps, effective detection of the asphalt content in the recycled asphalt mixture can be achieved.

[0112] In order to further improve the detection efficiency and accuracy, a number of improvements and optimizations have been made to the operation of the asphalt automatic extraction instrument:

[0113] Increase the number of automatic cleaning times, replace new centrifugal cylinders and filter paper: According to the type and characteristics of the asphalt mixture, increase the number of equipment cleaning times and the low-speed operation time to 1200 seconds, and replace new centrifugal cylinders and filter paper to ensure the cleaning effect while reducing the loss of mineral powder.

[0114] Establish testing standards: According to different types of asphalt mixtures and testing requirements, formulate corresponding testing standards and operating procedures to ensure the accuracy and consistency of test results.

[0115] Operator training: Operators are systematically trained and assessed to ensure they are familiar with equipment operation, understand test standards, and can accurately record and analyze test results.

[0116] Regular maintenance and calibration: Regularly maintain and calibrate the equipment to ensure it is in good working condition and meets accuracy requirements.

[0117] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for testing asphalt content based on an automatic asphalt extractor, characterized in that: The following steps are involved: S1. Prepare asphalt mixture samples with a mass of 1000 to 1500 g. Select an appropriate sample mass range according to the particle size of the asphalt mixture and ensure that the sample is in a loose state and the temperature is below 100°C; S2. Place the filter paper correctly in the centrifuge cylinder of the automatic extractor and weigh the combined mass of the centrifuge cylinder and filter paper (m 1-1 ); S3, stack the multi-level screens from top to bottom according to their sizes to form a set of screens, and weigh the mass of the set of screens (m2); S4. Place the asphalt mixture sample on the top sieve and install the centrifugal cylinder and the sieve on the fully automatic extractor; S5. Check whether the amount of trichloroethylene solvent in the automatic extractor is sufficient and ensure that the cooling water flows normally; S6. Start the fully automatic extraction instrument for cleaning. After cleaning, let it stand for a while. After the liquid guide tube stops leaking, remove the sieve and replace the centrifuge cylinder and filter paper. S7. Use a clean glass rod to gently stir the mixture, restart, and clean again. Check the state of the mixture. If there is obvious black asphalt, repeat step S6 until there is no obvious black asphalt; S8. When there is no obvious black asphalt, dry the materials in the sieve and centrifuge to constant weight, and weigh the combined mass of the sieve and mineral material (m5) and the combined mass of the centrifuge, filter paper and mineral powder (m 4-n ); S9. Conduct screening test on the dried ore to determine the quality of ore at each particle size level; S10. Calculate the total mass (m) of the mineral aggregate in the asphalt mixture based on the weighing results and the screening test results. a ), and calculate the asphalt content (P b ) and oil-stone ratio (P a ).

2. The asphalt content test method based on the asphalt automatic extraction instrument according to claim 1 is characterized in that: In step S5, the amount of trichloroethylene solvent loaded into the fully automatic extractor should reach 2 / 3 of the container capacity to ensure the cleaning effect.

3. The asphalt content test method based on the asphalt automatic extraction instrument according to claim 1 is characterized in that: In step S7, the number of repeated cleaning is determined according to the characteristics of the asphalt mixture sample and the cleaning effect, and a new centrifugal cylinder and filter paper are replaced at the same time until there is no obvious black asphalt in the sieve.

4. The asphalt content test method based on the asphalt automatic extraction instrument according to claim 1 is characterized in that: In step S8, the material is dried at a temperature of 100±5°C and dried to a constant weight. 100±5°C ensures that trichloroethylene does not produce toxic chlorine gas during the drying process.

5. The asphalt content test method based on the asphalt automatic extraction instrument according to claim 1 is characterized in that: In step S10, the asphalt content (P b ) and oil-stone ratio (P a ) are calculated as follows: Where m0 is the mass of the asphalt mixture sample, m a It is the total mass of aggregate in asphalt mixture.

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