Solid asphalt detection method, device and system based on magnetorheological effect

Abstract

The invention discloses a solid asphalt detection method, device and system based on a magnetorheological effect, and relates to the technical field of material detection.The method comprises the steps that an asphalt sample is taken out from on-site concurrently-maintained asphalt, and the asphalt sample is heated to be in a flowing state; mixing and curing the magnetic powder and the asphalt sample in the flowing state to form a magnetorheological asphalt composite material sample; measuring rheological parameters of the magnetorheological asphalt composite material sample under different magnetic field intensities; calculating the change rate of the rheological parameters; according to the change rate of the rheological parameters and a preset standard curve, the aging condition of the on-site co-curing asphalt is evaluated, and the standard curve is used for recording the relation between the change rate of the rheological parameters and the aging degree of the asphalt. With the adoption of the device and the method, the asphalt aging problem caused by repeated heating in the asphalt test can be avoided, and the asphalt rheological parameters and the aging condition can be detected.

Description

Technical Field

[0001] The present invention relates to the technical field of material testing, and particularly to a method, device and system for detecting solid asphalt based on the magnetorheological effect. Background Art

[0002] In projects such as road construction and building waterproofing, the performance of asphalt is directly related to the project quality and service life. However, the existing asphalt tests mainly have the following problems: I. Distorted test results In traditional asphalt tests, it is common to repeatedly heat asphalt samples. The sensitivity of asphalt to heating is not fully considered, and there is a lack of effective technical means to avoid heating aging. For example, in the asphalt aging test, due to the need for sample preparation and test procedures, it is necessary to heat the asphalt multiple times. During the heating process, chemical reactions such as oxidation and polymerization occur in the asphalt, changing its chemical composition and physical structure, and thus leading to performance changes, making the test data unable to truly reflect the actual performance of the asphalt and affecting the evaluation of project quality and material selection.

[0003] II. Inaccurate on-site observation The existing observation methods for the in-situ co-cured asphalt aging situation are also relatively limited. Most of them are through visual observation, simple hardness testing, etc., and it is impossible to accurately obtain the changes in the internal structure and performance of the asphalt, making it difficult to provide accurate aging information.

[0004] III. Low detection efficiency The repeated heating process takes a long time, and coupled with the limitations of the existing on-site observation methods, the entire detection process has low efficiency and cannot meet the requirements of the rapid development of engineering construction.

[0005] As can be seen from the above, traditional asphalt tests focus on macroscopic performance testing, ignoring the microscopic structural changes and the influence of heating on the performance of asphalt, and do not fundamentally solve the problems of repeated heating and on-site observation. At the same time, traditional asphalt tests are not only inefficient, but also have large errors in test results and are difficult to meet the actual needs of projects. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method, device and system for detecting solid asphalt based on the magnetorheological effect, which can realize the detection of asphalt rheological parameters and aging situation.

[0007] To solve the above technical problems, the present invention provides a method for detecting solid asphalt based on the magnetorheological effect, including: taking out an asphalt sample from on-site cured asphalt and heating the asphalt sample to a flowing state; mixing and curing magnetic powder with the asphalt sample in the flowing state to form a magnetorheological asphalt composite sample; measuring the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities; calculating the change rate of the rheological parameters; and evaluating the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and a preset standard curve, where the standard curve is used to record the relationship between the change rate of the rheological parameters and the aging degree of the asphalt.

[0008] As an improvement of the above solution, the rheological parameters include viscosity and / or shear stress.

[0009] As an improvement of the above solution, the step of mixing and curing magnetic powder with the asphalt sample in the flowing state includes: adding magnetic powder to the asphalt sample in the flowing state; stirring the asphalt sample in the flowing state and the magnetic powder, and uniformly dispersing the magnetic powder in the asphalt sample in the flowing state to form a mixed sample; pouring the mixed sample into a standard sample mold; and cooling and curing the mixed sample in the standard sample mold at room temperature to form a magnetorheological asphalt composite sample.

[0010] As an improvement of the above solution, the weight ratio of the magnetic powder to the asphalt sample in the flowing state is 3 - 5:100.

[0011] As an improvement of the above solution, during the stirring process, the stirring speed is 2000 - 3000 revolutions per minute, and the stirring time is 10 - 15 minutes.

[0012] As an improvement of the above solution, the step of measuring the rheological parameters of the magnetorheological asphalt under different magnetic field intensities includes: placing the magnetorheological asphalt composite sample on the test bench of a rheological property testing instrument; starting a magnetic field generating device, and making the magnetic field generated by the magnetic field generating device act on the magnetorheological asphalt composite sample; gradually increasing the magnetic field intensity of the magnetic field generated by the magnetic field generating device; and respectively collecting the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities through the rheological property testing instrument.

[0013] As an improvement of the above solution, before measuring the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities, it further includes: respectively calibrating the magnetic field generating device and the rheological property testing instrument.

[0014] As an improvement of the above solution, the change rate of the rheological parameters is positively correlated with the aging degree of the asphalt.

[0015] Accordingly, the present invention also provides a solid asphalt detection device based on the magnetorheological effect, which includes: an acquisition module for acquiring rheological parameters of a magnetorheological asphalt composite sample under different magnetic field strengths, where the magnetorheological asphalt composite sample is formed by mixing and curing magnetic powder with an asphalt sample in a flowing state, and the asphalt sample in the flowing state is taken out from on-site cured asphalt and heated; a calculation module for calculating the change rate of the rheological parameters; an evaluation module for evaluating the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and a preset standard curve, where the standard curve is used to record the relationship between the change rate of the rheological parameters and the aging degree of the asphalt.

[0016] Accordingly, the present invention also provides a solid asphalt detection system based on the magnetorheological effect, which includes a heating device, a stirrer, a sample mold, a magnetic field generating device, a rheological property testing instrument, and the above-mentioned solid asphalt detection device based on the magnetorheological effect; the heating device is used to heat the asphalt sample to a flowable state; the stirrer is used to mix the magnetic powder with the asphalt sample in the flowing state; the sample mold is used to load the magnetic powder and the asphalt sample in the flowing state after the mixing process; the magnetic field generating device is used to generate different magnetic field strengths; the rheological property testing instrument is used to measure the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field strengths.

[0017] Implementing the present invention has the following beneficial effects: The present invention only needs to heat the asphalt sample once, which can avoid the asphalt aging problem caused by repeated heating in asphalt tests; at the same time, the present invention utilizes the magnetorheological effect to accurately measure the change in the rheological properties of asphalt; the present invention also establishes the corresponding relationship between the rheological parameters and the aging degree of asphalt, so as to realize the detection of the aging condition of asphalt; In addition, the solid asphalt detection system based on the magnetorheological effect of the present invention is small in volume, easy to carry, and simple to operate, which can meet the requirements of rapid detection on the engineering site. Description of the Drawings

[0018] Figure 1 is a flowchart of the first embodiment of the solid asphalt detection method based on the magnetorheological effect of the present invention; Figure 2 is a flowchart of the second embodiment of the solid asphalt detection method based on the magnetorheological effect of the present invention; Figure 3 is a schematic structural diagram of an embodiment of the magnetic field generating device and the rheological property testing instrument in the present invention; Figure 4 is a schematic structural diagram of an embodiment of the solid asphalt detection device based on the magnetorheological effect in the present invention. Detailed Embodiments

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. It is hereby declared that the orientation terms such as above, below, left, right, front, rear, inner, and outer that appear or will appear in the text of the present invention are only based on the accompanying drawings of the present invention, and they do not specifically limit the present invention.

[0020] See Figure 1 , Figure 1 which shows a flowchart of the first embodiment of the solid asphalt detection method based on the magnetorheological effect of the present invention, and it includes: S101, Take out an asphalt sample from the on-site cured asphalt and heat the asphalt sample to a flowing state; During detection, first take out an appropriate amount of asphalt sample from the on-site cured asphalt and heat the asphalt sample to a flowable state; during the heating process, the heating time should be minimized as much as possible to reduce the aging effect.

[0021] S102, Mix and cure the magnetic powder with the asphalt sample in a flowing state to form a magnetorheological asphalt composite sample; Correspondingly, the steps of mixing and curing the magnetic powder with the asphalt sample in a flowing state include: (1) Add magnetic powder to the asphalt sample in a flowing state; Generally, magnetic powder can be added to the asphalt sample in a flowing state according to a preset ratio; preferably, the weight ratio of the magnetic powder to the asphalt sample in a flowing state is 3 - 5:100, that is, 3 - 5 g of magnetic powder is added to every 100 g of asphalt sample. Among them, the magnetic powder is made of a permanent magnetic material.

[0022] (2) Stir the asphalt sample and the magnetic powder in a flowing state and make the magnetic powder evenly dispersed in the asphalt sample in a flowing state to form a mixed sample; During the stirring process, a stirrer can be used for stirring; among them, the rotation speed of the stirrer can be adjusted to ensure that the magnetic powder is evenly mixed in the asphalt sample.

[0023] When performing the stirring treatment, the stirring speed is preferably 2000 - 3000 revolutions per minute, and the stirring time is preferably 10 - 15 minutes to make the magnetic powder evenly dispersed in the asphalt sample.

[0024] It should be noted that a stirring speed of 2000 - 3000 revolutions per minute can ensure the rapid and uniform dispersion of magnetic powder in asphalt, forming a stable magnetorheological composite material, avoiding the agglomeration or precipitation of magnetic powder caused by low-speed stirring, and at the same time avoiding excessive air bubbles or exacerbating the thermal oxidation of asphalt due to too high a speed; while when the stirring speed is less than 2000 revolutions per minute, the stirring force is insufficient, and the magnetic powder is prone to agglomeration or precipitation, resulting in non-uniform composite materials, unstable magnetorheological effects, and large fluctuations in the measurement results of rheological parameters; when the stirring speed is greater than 3000 revolutions per minute, it may exacerbate the breakage of asphalt molecular chains, introduce additional thermal aging, and at the same time is prone to entrain air to form bubbles, interfering with rheological tests (such as bubbles will reduce the true shear stress during viscosity measurement).

[0025] In addition, a stirring time of 10 - 15 minutes can enable the full mixing of magnetic powder and asphalt, ensure the uniform distribution of magnetic powder, avoid measurement deviations of rheological parameters caused by uneven mixing, and at the same time control the heating duration to reduce the thermal aging of asphalt; while when the stirring time is less than 10 minutes, the magnetic powder is not fully dispersed, the local concentration is uneven, the rheological responses under the action of the magnetic field are inconsistent, and the repeatability of the measurement results is poor; when the stirring time is greater than 15 minutes, the heating time is extended, increasing the risk of asphalt oxidation, which violates the invention purpose of "reducing heating aging".

[0026] (3) Pour the mixed sample into a standard sample mold; Using a standard sample mold can produce magnetorheological asphalt composite material samples with uniform sizes, facilitating subsequent tests and data comparison.

[0027] (4) The mixed sample in the standard sample mold is rapidly cooled and solidified at room temperature to form a magnetorheological asphalt composite material sample.

[0028] S103, Measure the rheological parameters of the magnetorheological asphalt composite material sample under different magnetic field intensities; It should be noted that the rheological parameters include viscosity and / or shear stress, that is, the viscosity of the magnetorheological asphalt composite material sample under different magnetic field intensities can be measured alone, the shear stress of the magnetorheological asphalt composite material sample under different magnetic field intensities can be measured alone, or the viscosity and shear stress of the magnetorheological asphalt composite material sample under different magnetic field intensities can be measured simultaneously.

[0029] Correspondingly, the steps for measuring the rheological parameters of the magnetorheological asphalt composite material sample under different magnetic field intensities include: (1) Place the magnetorheological asphalt composite material sample on the test bench of the rheological property test instrument; (2) Start the magnetic field generating device and make the magnetic field generated by the magnetic field generating device act on the magnetorheological asphalt composite material sample; (3) Gradually increase the magnetic field intensity of the magnetic field generated by the magnetic field generating device; (4) Collect the rheological parameters of the magnetorheological asphalt composite material samples under different magnetic field strengths through a rheological property testing instrument.

[0030] For example, when starting the magnetic field generating device, the initial magnetic field strength can be set to 0.5 Tesla; after setting the initial magnetic field strength, the initial viscosity of the magnetorheological asphalt composite material sample under the condition of an initial magnetic field strength of 0.5 Tesla can be collected through a rheological property testing instrument and / or the initial shear stress ; Subsequently, gradually increase the magnetic field strength by 0.5 Tesla each time, and measure the corresponding viscosity and / or shear stress at each magnetic field strength, and record the changes in rheological parameters under different magnetic field strengths.

[0031] It should be noted that when the initial magnetic field strength is set to be less than 0.5 Tesla, the magnetic field strength is too low, the magnetic powder is not sufficiently aligned, the change range of rheological parameters is small, which may be lower than the detection accuracy of the instrument, resulting in measurement errors or failure to capture effective signals; when the initial magnetic field strength is set to be greater than 0.5 Tesla, the initial magnetic field is too strong, which will cause the magnetic powder to quickly form a tight chain structure, resulting in a sudden increase in rheological parameters (such as viscosity), exceeding the upper limit of the instrument range; the response range is limited when gradually increasing the magnetic field subsequently, and it is difficult to distinguish the rheological differences of asphalt with different aging degrees; therefore, the initial magnetic field strength in the present invention is set to 0.5 Tesla, wherein 0.5 Tesla can trigger an obvious magnetorheological effect (the magnetic powder starts to be aligned, changing the viscosity and shear stress of the asphalt), and avoid the rheological parameters exceeding the measurement range of the instrument due to too strong a magnetic field, ensuring a linear response of the data when gradually increasing the magnetic field subsequently.

[0032] S104, calculate the change rate of the rheological parameters; According to the measured rheological parameter data, calculate the change rate of the rheological parameters: For example, the viscosity change rate can be calculated according to the following formula :

[0033] where is the initial viscosity, is the th viscosity after increasing the magnetic field strength.

[0034] Again, for example, the shear stress change rate can be calculated according to the following formula :

[0035] where is the initial shear stress, is the Shear stress after increasing the magnetic field strength for the second time.

[0036] S105. Evaluate the aging condition of on-site asphalt cured under the same conditions according to the change rate of rheological parameters and the preset standard curve.

[0037] It should be noted that the standard curve is used to record the relationship between the change rate of rheological parameters and the aging degree of asphalt. Among them, the standard curve can be obtained by fitting a large number of test data of asphalt samples with different aging degrees.

[0038] Since the rheological parameters include viscosity and / or shear stress, the standard curve also includes a viscosity standard curve and / or a shear stress standard curve.

[0039] The specific fitting process of the standard curve is as follows: (1.1) Prepare standard asphalt samples with different aging degrees: Prepare a series of asphalt samples through artificial aging tests (such as rolling thin film oven aging, ultraviolet aging), and control the aging time (such as 0h, 20h, 40h, 60h) or aging index (such as mass loss rate, viscosity ratio) as the known aging degree benchmark. (1.2) Prepare magnetorheological composites: Mix magnetic powder with asphalt of each aging degree according to the method, and control the magnetic powder ratio (3 - 5:100), stirring speed (2000 - 3000 revolutions per minute) and time (10 - 15 minutes) to be consistent to ensure the standardization of sample preparation. (1.3) Measure the change rate of rheological parameters: Apply a magnetic field increasing step by step from 0 to 3T to each sample, record the viscosity and shear stress under different magnetic fields, and calculate Δη and Δτ (see the calculation method above).

[0040] (1.4) Data fitting: Take the aging degree (such as aging time, aging index) as the ordinate and Δη or Δτ as the abscissa, and establish a standard curve through linear regression or polynomial fitting. For example, a model example: aging index = k1×Δη + b1; where Δη = (ηi - η0)×100% / η0, η0 is the initial viscosity, ηi is the viscosity at the i-th level of magnetic field, and k1, b1 are fitting coefficients. Generally, aging causes the cross-linking of asphalt molecular chains and the increase of polar groups, enhancing the interaction between magnetic powder and asphalt, and resulting in a greater increase in viscosity under the magnetic field.

[0041] Another example, a model example: aging index = k2×Δτ + b2; where Δτ = (τi - τ0)×100% / τ0, τ0 is the initial shear stress, τi is the shear stress at the i-th level of magnetic field, and k2, b2 are fitting coefficients. Generally, aging hardens the internal structure of asphalt, and the shear stress increases at a faster rate with the increase of magnetic field.

[0042] That is to say, the independent variables in the fitting process are: magnetic field strength (0.5T, 1.0T, 1.5T, etc.), the change rate of rheological parameters (Δη, Δτ); the dependent variable is: the quantification index of asphalt aging degree (such as aging time, aging index based on ductility / softening point); the fitting method is: using the least square method for fitting, and determining the best mathematical relationship between the change rate and the aging degree through statistical analysis to ensure the accuracy and universality of the standard curve.

[0043] Correspondingly, the change rate of rheological parameters is positively correlated with the aging degree of asphalt; that is, the greater the change rate of rheological parameters, the higher the aging degree of asphalt, and the smaller the change rate of rheological parameters, the lower the aging degree of asphalt.

[0044] During the evaluation process, the change rate of rheological parameters measured in real time can be compared with the change rate of rheological parameters recorded in the standard curve to find out the aging degree corresponding to the change rate of rheological parameters, so as to realize the accurate detection of the aging degree of solid asphalt.

[0045] As can be seen from the above, the present invention utilizes the magnetorheological effect to uniformly mix magnetic powder made of permanent magnetic material into the asphalt sample to form a magnetorheological asphalt composite material. Under the action of an external magnetic field, the magnetic powder will form a specific structure in the asphalt, changing the rheological properties of the asphalt. As the asphalt ages, the change of its internal structure will cause corresponding changes in the magnetorheological effect. By measuring the rheological parameters (such as viscosity, shear stress, etc.) of the magnetorheological asphalt composite material under different magnetic field conditions and establishing the corresponding relationship between the rheological parameters and the aging degree of asphalt, the detection of the aging situation of asphalt can be realized.

[0046] See Figure 2 , Figure 2 shows the flowchart of the second embodiment of the solid asphalt detection method based on the magnetorheological effect of the present invention, which includes: S201, taking out the asphalt sample from the on-site cured asphalt and heating the asphalt sample to a flowing state; S202, mixing and curing the magnetic powder with the asphalt sample in a flowing state to form a magnetorheological asphalt composite material sample; S203, calibrating the magnetic field generating device and the rheological property testing instrument respectively; Different from the first embodiment shown in Figure 1 , in this embodiment, before using the magnetic field generating device and the rheological property testing instrument, it is necessary to calibrate the magnetic field generating device and the rheological property testing instrument, that is, calibrate the magnetic field strength and the measurement of rheological parameters using a standard sample to ensure the accuracy of the equipment measurement.

[0047] S204, measure the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field strengths; S205, calculate the change rate of the rheological parameters; S206, evaluate the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and the preset standard curve.

[0048] Therefore, the present invention can avoid the asphalt aging problem caused by repeated heating in asphalt tests by using the magnetorheological effect, ensuring the accuracy and reliability of the test results (such as viscosity, initial shear stress); meanwhile, the present invention can conduct real-time and accurate observation on the aging condition of the on-site cured asphalt, providing more scientific asphalt performance data for projects such as road construction and building waterproofing, and helping to improve the project quality and optimize the material selection.

[0049] See Figure 3 and Figure 4 , Figure 3 and Figure 4 show the specific structure of the solid asphalt detection system based on the magnetorheological effect of the present invention, which includes a heating device, a stirrer, a sample mold, a magnetic field generating device 1, a rheological property testing instrument 2 and a solid asphalt detection device 3 based on the magnetorheological effect.

[0050] The heating device, the stirrer, the sample mold, the magnetic field generating device 1, the rheological property testing instrument 2 and the solid asphalt detection device 3 based on the magnetorheological effect will be described in detail below: I. Heating device The heating device is used to heat the asphalt sample to a flowable state.

[0051] II. Stirrer The stirrer is used to mix the magnetic powder with the asphalt sample in a flowable state; preferably, the stirrer in this embodiment can adopt a high-speed shear stirrer, and the rotation speed of the stirrer can be adjusted to ensure that the magnetic powder is evenly dispersed in the asphalt sample.

[0052] III. Sample mold The sample mold is used to load the magnetic powder and the asphalt sample in a flowable state after the mixing process.

[0053] Through the standard sample mold, it is convenient to make magnetorheological asphalt composite samples with unified dimensions, providing a guarantee for subsequent tests and data comparison.

[0054] IV. Magnetic field generating device The magnetic field generating device 1 is used to generate different magnetic field strengths.

[0055] Such as Figure 3As shown in the figure, the magnetic field generating device 1 includes two adjustable ring-shaped permanent magnets 11 arranged opposite to each other, which has a compact structure and is convenient to carry to the site for use. At the same time, the ring-shaped permanent magnet 11 can generate a continuously adjustable magnetic field intensity in the range of 0 to 3 Tesla.

[0056] V. Rheological Property Testing Instrument The rheological property testing instrument 2 is used to measure the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities.

[0057] In this embodiment, the rheological property testing instrument 2 can be a rheometer, which is equipped with high-precision sensors and can accurately measure parameters such as the viscosity and shear stress of the sample.

[0058] VI. Solid Asphalt Detection Equipment Based on Magnetorheological Effect As Figure 4 shown, the solid asphalt detection equipment 3 based on the magnetorheological effect includes: An acquisition module 31 for acquiring the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities. Among them, the magnetorheological asphalt composite sample is formed by mixing and curing magnetic powder with an asphalt sample in a flowing state, and the asphalt sample in a flowing state is taken out from the on-site cured asphalt and heated. A calculation module 32 for calculating the change rate of the rheological parameters. It should be noted that the rheological parameters include viscosity and / or shear stress, and the viscosity change rate The calculation formula is: , and the shear stress change rate The calculation formula is: , where is the initial viscosity, is the viscosity after the th increase in magnetic field intensity, is the initial shear stress, is the shear stress after the th increase in magnetic field intensity.

[0059] An evaluation module 33 for evaluating the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and a preset standard curve. Among them, the standard curve is used to record the relationship between the change rate of the rheological parameters and the aging degree of the asphalt, and the standard curve can be obtained by fitting a large number of test data of asphalt samples with different aging degrees. Correspondingly, the change rate of the rheological parameters is positively correlated with the aging degree of the asphalt. That is, the greater the change rate of the rheological parameters, the higher the aging degree of the asphalt, and the smaller the change rate of the rheological parameters, the lower the aging degree of the asphalt.

[0060] During operation, first take an appropriate amount of asphalt sample from the on-site cured asphalt, and heat the asphalt sample to a flowable state through a heating device; then, add magnetic powder to the asphalt sample in a flowable state according to a preset ratio, and use a stirrer to stir the asphalt sample and magnetic powder in a flowable state at a stirring speed of 2000 - 3000 revolutions per minute for 10 - 15 minutes, and make the magnetic powder evenly dispersed in the asphalt sample in a flowable state to form a mixed sample; then, pour the mixed sample into a standard sample mold and quickly cool and solidify it at room temperature to form a magnetorheological asphalt composite material sample; subsequently, calibrate the magnetic field generating device 1 and the rheological property testing instrument 2 respectively; then, place the magnetorheological asphalt composite material sample on the test bench 21 of the rheological property testing instrument 2, start the magnetic field generating device 1 and set the initial magnetic field strength to 0.5 Tesla, and then collect the initial viscosity and initial shear stress of the magnetorheological asphalt composite material sample through the rheological property testing instrument 2; subsequently, adjust the magnetic field generating device 1 to gradually increase the magnetic field strength by 0.5 Tesla each time, and measure the corresponding viscosity and shear stress through the rheological property testing instrument 2 at each magnetic field strength, and record the change of rheological parameters at different magnetic field strengths; finally, calculate the change rate of the rheological parameters through the solid asphalt detection device 3, and evaluate the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and the preset standard curve.

[0061] In summary, the present invention has the following beneficial effects: 1. Avoid the influence of aging. The entire detection process does not require repeated heating of the asphalt. By accurately measuring the change of the rheological properties of the asphalt through the magnetorheological effect, the problem of asphalt aging caused by heating is effectively avoided, ensuring that the detection results can truly reflect the actual properties of the asphalt.

[0062] 2. Accurately observe on-site. Detect the on-site cured asphalt, and accurately observe the aging condition of the asphalt through the magnetorheological effect, providing timely and accurate asphalt performance data for the engineering site.

[0063] 3. Simple and efficient operation. The detection equipment is miniaturized and portable, with simple operation and relatively fast detection process, which can improve the detection efficiency and meet the requirements of rapid detection on the engineering site.

[0064] The above is the preferred implementation mode of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A solid asphalt detection method based on magnetorheological effect, characterized in that: Comprising: Taking out an asphalt sample from on-site cured asphalt and heating the asphalt sample to a flowing state; Mixing and curing magnetic powder with the asphalt sample in the flowing state to form a magnetorheological asphalt composite sample; Measuring the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities; Calculating the change rate of the rheological parameters; Evaluating the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and a preset standard curve, wherein the standard curve is used to record the relationship between the change rate of the rheological parameters and the aging degree of the asphalt.

2. The solid asphalt detection method based on the magnetorheological effect according to claim 1, wherein The rheological parameters include viscosity and / or shear stress.

3. The solid asphalt detection method based on the magnetorheological effect according to claim 1 or 2, characterized in that, The step of mixing and curing magnetic powder with the asphalt sample in the flowing state includes: Adding magnetic powder to the asphalt sample in the flowing state; Stirring the asphalt sample and the magnetic powder in the flowing state and uniformly dispersing the magnetic powder in the asphalt sample in the flowing state to form a mixed sample; Pouring the mixed sample into a standard sample mold; The mixed sample in the standard sample mold is cooled and cured at room temperature to form a magnetorheological asphalt composite sample.

4. The solid asphalt detection method based on the magnetorheological effect according to claim 3, wherein, The weight ratio of the magnetic powder to the asphalt sample in the flowing state is 3 - 5:

100.

5. The solid asphalt detection method based on the magnetorheological effect according to claim 3, characterized in that, During the stirring process, the stirring speed is 2000 - 3000 revolutions per minute and the stirring time is 10 - 15 minutes.

6. The solid asphalt detection method based on the magnetorheological effect according to claim 1 or 2, characterized in that, The step of measuring the rheological parameters of the magnetorheological asphalt under different magnetic field intensities includes: Placing the magnetorheological asphalt composite sample on the test bench of a rheological property testing instrument; Starting a magnetic field generating device and making the magnetic field generated by the magnetic field generating device act on the magnetorheological asphalt composite sample; Gradually increasing the magnetic field intensity of the magnetic field generated by the magnetic field generating device; Collecting the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities through the rheological property testing instrument respectively.

7. The solid asphalt detection method based on the magnetorheological effect according to claim 6, wherein Before measuring the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities, it further includes: calibrating the magnetic field generating device and the rheological property testing instrument respectively.

8. The method for detecting solid asphalt based on magnetorheological effect according to claim 1 or 2, characterized in that, The change rate of the rheological parameters is positively correlated with the aging degree of the asphalt.

9. A solid asphalt detection device based on the magnetorheological effect, characterized in that, Comprising: An acquisition module for acquiring the rheological parameters of a magnetorheological asphalt composite sample under different magnetic field intensities, the magnetorheological asphalt composite sample being formed by mixing and curing magnetic powder with an asphalt sample in a flowing state, and the asphalt sample in the flowing state being taken out from on-site cured asphalt and heated; A calculation module for calculating the change rate of the rheological parameters; An evaluation module for evaluating the aging condition of the on-site cured asphalt according to the change rate of the rheological parameters and a preset standard curve, wherein the standard curve is used to record the relationship between the change rate of the rheological parameters and the aging degree of the asphalt.

10. A solid asphalt detection system based on the magnetorheological effect, characterized in that, Including a heating device, a stirrer, a sample mold, a magnetic field generating device, a rheological property testing instrument, and the solid asphalt detection device based on the magnetorheological effect as claimed in claim 9; The heating device is used to heat the asphalt sample to a flowable state; The stirrer is used to mix magnetic powder with the asphalt sample in the flowing state; The sample mold is used to load the magnetic powder after mixing treatment and the asphalt sample in a flowing state; The magnetic field generating device is used to generate different magnetic field intensities; The rheological property testing instrument is used to measure the rheological parameters of the magnetorheological asphalt composite sample under different magnetic field intensities.

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