URP asphalt mixture track evaluation method for super-heavy load road

Abstract

The invention relates to improvement of a heavy-load asphalt mixture track evaluation system and selection of new technical indexes. The problems that when the dynamic stability of a Chinese rutting test is larger than 6000 times / mm, the result variability is large, the monitoring result credibility is not high, the test temperature environment and the load condition cannot accurately simulate the actual temperature and the traffic environment, and the test index cannot well reflect the high rutting resistance of the mixture are mainly solved. The rut evaluation system has the following advantages: the strain detection precision is improved, the reliability of detecting a mixture with the dynamic stability greater than 6000 times / mm is improved, and the reliable detection range is expanded to 60000 times / mm; the temperature of 70 + / -0.5 DEG C is supplemented on the basis of the index of the temperature of 60 + / -0.5 DEG C, and the actual condition of the traffic environment temperature is better met; and the test pressure is changed from 0.7 MPa + / -0.05 MPa to 1MPa + / -0.05 MPa, so that the test condition can better simulate the actual condition of a heavy-load road. The heavy-duty road rut evaluation system can guide and select the mixture meeting the heavy-duty road use requirements more scientifically, more accurately and more favorably.

Description

Technical Field

[0001] The present invention relates to the technical field of rut evaluation systems, and particularly to a method for evaluating the rut of URP asphalt mixture for overweight roads. Background Art

[0002] As the most common disease, it is particularly important to accurately evaluate the rut resistance of asphalt mixtures.

[0003] However, there are some deficiencies in the existing rut evaluation methods and technical indicators, specifically manifested as follows: (1) The pressure value in the specification is much lower than the true value under actual overloading conditions: In the traditional rut test, the grounding pressure of the test wheel is usually 0.7 MPa, while the pressure in the actual heavy traffic environment can reach above 1.0 MPa, far greater than this standard. Therefore, the test results often cannot truly reflect the actual working conditions. (2) The test temperature condition is lower than the actual high temperature value of the asphalt pavement: The test temperature in the specification is 60 °C, while the highest temperature of the asphalt pavement can reach 70 °C under the summer gas conditions in most areas of our country. Especially during continuous high temperature periods, the impact on the asphalt pavement is even higher. Experimental studies have shown that when the test condition is increased from 60 °C to 70 °C, the high temperature performance of traditional asphalt mixtures shows a cliff-like decline, which is also a main cause of rut diseases. Therefore, the test temperature condition is too low, which does not conform to the actual situation of the highest temperature in the asphalt pavement, resulting in the evaluation results being unable to accurately guide practice. (3) The strain test accuracy is insufficient: In the rut test method in the specification, the strain test accuracy is only 0.01. When the dynamic stability value of the rut test reaches more than 6000 times / mm, the calculated results will cause the coefficient of variation of each test value to not meet the upper limit requirement of 20% in the specification due to the strain test accuracy problem. Therefore, the accuracy of the test data is greatly affected. (4) The requirements for test indicators are too low: The rut test index in the specification is 2800 times / mm, and the index of general rut resistance technology in the industry has been improved to the level of 8000 times / mm, but it is actually difficult to meet the rut resistance requirements in the actual asphalt pavement, that is, the rut disease cannot be solved. Practice has shown that it needs to be increased to more than 20000 times / mm to achieve a more ideal effect.

[0004] These defects not only affect the accurate evaluation and prediction of the high temperature rut resistance of asphalt mixtures, but also make it difficult for road design, construction units, and evaluation units, etc. to select suitable asphalt mixtures, increasing the risk of misjudgment, and further increasing the quality risk of asphalt pavements, resulting in many unnecessary rework and maintenance costs. Summary of the Invention

[0005] The present invention provides a rut evaluation method for URP asphalt mixture on overweight roads with higher experimental accuracy, more accurate evaluation, and test indicators more in line with actual application conditions. This method is applicable to measuring the high-temperature rutting resistance of asphalt mixtures and is used for detecting and evaluating the high-temperature rutting performance of asphalt mixtures.

[0006] The technical solution adopted by the present invention is: a rut evaluation method for URP asphalt mixture on overweight roads, which can more accurately simulate the actual environment of rutting under high-temperature conditions in summer on heavy-duty roads in the laboratory, and expand the detection range of dynamic stability. The test method adopts the rut test method T0719 - 1993 in the "JTJ052 - 2000 Test Procedures for Bitumen and Bituminous Mixtures in Highway Engineering".

[0007] The strain monitoring device of the evaluation system is changed to a dial gauge, meeting the upper limit requirement of a 20% coefficient of variation for the test. Since the measurement error will cause the coefficient of variation to exceed the range when the dynamic stability value of the asphalt mixture exceeds 6000 times / mm in the test method in the specification, the dial gauge is proposed; the additional load is increased from 0.7MPa ± 0.05MPa to 1.0MPa ± 0.05MPa because the actual vehicle pressure can reach 1.0MPa under actual overweight conditions, which is more in line with the actual situation of overweight; the test temperature is increased from 60°C in the specification to 70°C because the asphalt pavement temperature can reach 70°C under high-temperature weather conditions in summer, which is more in line with the actual situation of the asphalt pavement in summer high-temperature weather; based on the dynamic stability index of loading 0.7MPa ± 0.05MPa at a temperature of 60°C ± 0.5°C, the dynamic stability indexes of loading 0.7MPa ± 0.05MPa at a temperature of 70°C ± 0.5°C and loading 1MPa ± 0.05MPa at a temperature of 70°C ± 0.5°C are supplemented, which can effectively simulate the action background of high temperature and overweight on the asphalt pavement; at the same time, the requirements for the dynamic stability index under corresponding conditions are proposed.

[0008] As a further improvement of the present invention, the additional load is increased from 0.7MPa ± 0.05MPa to 1.0MPa ± 0.05MPa.

[0009] As a further improvement of the present invention, the specimen rut strain monitoring device is adjusted to a dial gauge.

[0010] As a further improvement of the present invention, the technical indicators are supplemented with the dynamic stability index of not less than 20000 times / mm for loading 0.7MPa ± 0.05MPa at a temperature of 60°C ± 0.5°C, not less than 15000 times / mm for loading 0.7MPa ± 0.05MPa at a temperature of 70°C ± 0.5°C, and not less than 10000 times / mm for loading 1MPa ± 0.05MPa at a temperature of 70°C ± 0.5°C.

[0011] As a further improvement of the present invention, the credibility of the detection of the mixture with a dynamic stability greater than 6000 times / mm is improved, and the reliable detection range of the standard test method is extended to 60000 times / mm.

[0012] Beneficial effects of the present invention: (1) Improving evaluation accuracy: The more scientific evaluation system proposed by the present invention in combination with the actual situation of overweight and high-temperature conditions can more accurately evaluate the rutting resistance performance of heavy-duty road asphalt mixtures. In particular, in the present invention, the grounding pressure of the test wheel is adjusted from 0.7 MPa in the standard to 1.0 MPa ± 0.05 MPa, the test temperature is increased from 60 °C in the standard to 70 °C, and the strain test accuracy is increased from 0.01 in the standard to 0.001. These improvements make the test conditions closer to the pavement conditions under the actual heavy-duty traffic in summer high-temperature weather, especially in the southern summer high-temperature conditions and with a greater load. Therefore, it can more accurately predict the high-temperature rutting resistance ability of asphalt mixtures and the service life of roads, reduce the waste of natural resources and labor caused by rework and repeated maintenance due to inaccurate evaluation, and further improve the durability and driving safety of roads.

[0013] (2) Optimizing resource utilization: The method provided by the present invention can objectively evaluate the high-temperature rutting resistance ability of asphalt mixtures, avoid rework and repeated maintenance caused by inaccurate evaluation, and thus reduce the waste of natural resources and labor. Through the grounding pressure measurement experiment carried out at 70 °C, it can ensure that the test conditions are closer to the pavement conditions under the extreme heavy-duty traffic in summer high-temperature environment, and improve the reliability of the evaluation results. At the same time, the accurate evaluation results help to formulate a reasonable maintenance plan, extend the service life of roads, and further reduce the maintenance cost. In addition, the improvement of the strain test accuracy (0.001) can more carefully record and analyze the deformation of the specimen at different stages, so as to provide more accurate and reasonable evaluation data, and improve the accuracy and reliability of the overall evaluation. By increasing the test index value under the improved conditions to enhance the rutting resistance ability of asphalt pavements, it is ensured that the asphalt pavements can achieve the effect of not being damaged under heavy-duty high-temperature conditions. Detailed implementation manners

[0014] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer and more understandable, the present application will be further described in detail below in conjunction with embodiments. It should be understood that the embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0015] The present invention provides a rut evaluation method for overweight road URP asphalt mixture, which can more accurately simulate the actual environment of rutting under high temperature conditions in summer on heavy-duty roads in the laboratory and expand the detection range of dynamic stability values. The test method adopts the rut test method of T0719-1993 in the "JTJ052-2000 Test Procedures for Bitumen and Bituminous Mixtures in Highway Engineering". The strain monitoring device of the evaluation system is changed to a dial gauge; the additional load is increased from 0.7MPa ± 0.05MPa to 1.0MPa ± 0.05MPa; on the basis of the dynamic stability index of loading 0.7MPa ± 0.05MPa at a temperature of 60°C ± 0.5°C, the dynamic stability indexes of loading 0.7MPa ± 0.05MPa at a temperature of 70°C ± 0.5°C and loading 1MPa ± 0.05MPa at a temperature of 70°C ± 0.5°C are supplemented. The test index is increased from 2800 times / mm of traditional modified asphalt mixture to 20000 times / mm, 15000 times / mm under the condition of 70°C, and 10000 times / mm under the conditions of 70°C and 1MPa.

[0016] When the present invention is specifically implemented, it includes the following steps:

[0017] Step 1, determination of the grounding pressure of the test wheel: The determination is carried out at 70°C. Place a 50mm thick steel plate on the test bench, lay a millimeter grid paper on it, and then lay a new carbon paper on it. After applying a load of 1000N, make the test wheel generate a static pressure on the carbon paper, and the wheel pressure area can be obtained on the grid paper, and the grounding pressure can be calculated therefrom. When the pressure does not meet 1.0MPa ± 0.05MPa, the load should be adjusted;

[0018] Step 2, fabricate rut test specimens by the wheel rolling forming method: Prepare and form rut specimens in the laboratory or on the construction site. The size of the plate-shaped specimens is 300mm in length × 300mm in width × 50-100mm in thickness. Specimens with the required size can also be cut from the road surface;

[0019] Step 3: Demold the specimen and measure the density and void ratio;

[0020] Step 4: After the specimen is formed, it should be placed at room temperature together with the test mold for at least 12h. After the modified asphalt mixture is fully cured, the rut test can be carried out. The room temperature placement time should not be longer than one week.

[0021] The specific steps for preparing specimens with a wheel rolling forming machine in the laboratory of the present invention are as follows:

[0022] S1: Take out the preheated test mold from the oven, install the test mold frame, lay a piece of cut ordinary paper in the test mold to isolate the bottom and sides with the paper, and evenly load the well-mixed all asphalt mixture into the test mold in a circular motion from the edge to the center with a small spatula after slightly mixing it. The middle part should be slightly higher than the surrounding area;

[0023] S2: Remove the test mold frame, compact it once in a circular motion from the edge to the center with a preheated small compaction hammer, and level it into a convex circular arc;

[0024] S3: Insert a thermometer. When the mixture reaches the specified compaction temperature, lay a piece of cut ordinary paper on the surface;

[0025] S4: Preheat the rolling wheel to 100 °C before forming. Then, place the test mold filled with asphalt mixture on the platform of the wheel roller, gently lower the rolling wheel, and adjust the total load to 10 kN;

[0026] S5: Start the wheel roller, roll in one direction for 2 round trips (4 times), unload the load, then lift the rolling wheel, turn the specimen around, add the same load and roll until the Marshall standard density reaches 100% ± 1%. Before the specimen is officially compacted, after measuring that the density meets the requirements, determine the number of rolling times of the specimen;

[0027] S6: After compaction and forming, remove the paper on the surface, and mark the rolling direction on the surface of the specimen with chalk;

[0028] S7: Place the test mold containing the compacted specimen at room temperature to cool.

[0029] The specific steps for preparing specimens on the construction site in the present invention are as follows:

[0030] SS1: Take representative asphalt mixture samples, and the quantity should be more than 3;

[0031] SS2: Weigh the quantity of a sample mixture according to the laboratory method and load it into a test mold with the required size, and compact it evenly with a small hammer;

[0032] SS3: On the construction site, a small vibratory roller and other suitable rollers can be used for rolling. At the specified compaction temperature, each pass is rolled for 3 - 4 s, about 25 round trips, so that the compaction density of the asphalt mixture reaches the Marshall standard density of 100% ± 1%;

[0033] SS4: When sending the asphalt mixture sampled on the construction site to the laboratory for forming, the mixture must be placed in a heat-insulating bucket to prevent its temperature from dropping, and it should be formed immediately after arriving at the laboratory. If the temperature is lower than the requirement, it can be appropriately heated to the compaction temperature and then formed with a wheel rolling forming machine. For specimens that are reshaped after being reheated after complete cooling, it must be noted in the test report.

[0034] The secondary heating time of the present invention does not exceed 30 min.

[0035] The specific steps of the rutting test of the present invention are as follows: First, place the specimen together with the test mold on the test bench of the rutting test machine, ensure that the test wheel is located at the center of the specimen, and its traveling direction is consistent with the rolling and driving directions of the specimen; Turn on the rutting deformation automatic recorder and the test machine, and let the test wheel travel back and forth on the specimen for about 1 hour until the maximum deformation reaches 25 mm; During the test, the recorder automatically records the deformation curve and provides detailed test data.

[0036] During the process of the test wheel traveling back and forth on the specimen of the present invention, read the deformation values at 45 min and 60 min. Calculate the number of times required for 1 mm rut depth according to Formula 1 of the T0719-1993 rutting test method in the specification "JTJ052-2000 Test Procedures for Bitumen and Bituminous Mixtures in Highway Engineering" and record it as the dynamic stability index. The higher the dynamic stability index, the better the rutting resistance performance of the asphalt mixture under high-temperature conditions.

[0037] During the rutting test of the present invention, the strain test accuracy specification is 0.001 to ensure the scientificity and accuracy of large data values exceeding the specification upper limit of more than 6000 times / mm.

[0038] Example 1:

[0039] The present invention provides a rutting evaluation method for URP asphalt mixture for overweight roads, including the following steps:

[0040] Step 1, determination of the ground pressure of the test wheel: The determination is carried out at 70 °C. Place a 50-mm-thick steel plate on the test bench, lay a millimeter grid paper on it, lay a new carbon paper on it, apply a load of 1000 N, and make the test wheel generate a static pressure on the carbon paper. Then the wheel pressure area can be obtained on the grid paper, and the ground pressure can be calculated therefrom. When the pressure does not meet 1.0 MPa ± 0.05 MPa, the load should be adjusted;

[0041] Step 2: Fabricate the rut test specimen using the wheel rolling forming method: Take out the preheated test mold from the oven, install the test mold frame, lay a piece of cut ordinary paper in the test mold so that the bottom and sides are isolated by the paper. Slightly mix all the mixed asphalt mixture with a small spatula and then evenly load it into the test mold in a circular order from the edge to the middle. The middle part should be slightly higher than the surrounding. Remove the test mold frame, compact it once in a circular motion from the edge to the middle with a preheated small compaction hammer, and level it into a convex arc shape. Insert a thermometer. When the mixture reaches the specified compaction temperature, lay a piece of cut ordinary paper on the surface. Preheat the rolling wheel to 100 °C before forming. Then, place the test mold filled with asphalt mixture on the platform of the wheel rolling machine, gently lower the rolling wheel, and adjust the total load to 10 kN. Start the wheel rolling machine and roll it in one direction for 2 round trips (4 times), unload the load, then lift the rolling wheel, turn the specimen around, and apply the same load to roll it until the Marshall standard density reaches 100% ± 1%. Before the specimen is officially compacted, determine the rolling times of the specimen after measuring the density. After compaction and forming, remove the paper on the surface and mark the rolling direction on the surface of the specimen with chalk. Place the test mold containing the compacted specimen at room temperature to cool;

[0042] Step 3: Demold the specimen and measure its density and void ratio;

[0043] Step 4: After the specimen is formed, place it together with the test mold at normal temperature for at least 12 h. After the asphalt mixture is fully cured, the rut test can be carried out: First, place the specimen together with the test mold on the test bench of the rut testing machine, ensure that the test wheel is located at the center of the specimen, and its traveling direction is consistent with the rolling and driving directions of the specimen. Turn on the rut deformation automatic recorder and the testing machine, and let the test wheel travel back and forth on the specimen for about 1 hour until the maximum deformation reaches 25 mm. During the test, the recorder automatically records the deformation curve and provides detailed test data.

[0044] Example 2:

[0045] The present invention provides a rut evaluation method for URP asphalt mixture for overweight roads, including the following steps:

[0046] Step 1: Measurement of the grounding pressure of the test wheel: The measurement is carried out at 70 °C. Place a 50 - mm - thick steel plate on the test bench, lay a millimeter grid paper on it, and then lay a new carbon paper on it. After applying a load of 1000 N, make the test wheel generate a static pressure on the carbon paper, and then the wheel pressure area can be obtained on the grid paper, and the grounding pressure can be calculated from this. When the pressure does not meet 1.0 MPa ± 0.05 MPa, the load should be adjusted;

[0047] Step 2: Produce rutting test specimens using the wheel rolling forming method: Take representative asphalt mixture samples, with a quantity of more than 3; Weigh a sample mixture quantity according to the laboratory method and put it into a test mold with the required dimensions, and compact it evenly with a small hammer; On the construction site, a small vibratory roller and other suitable rollers can be used for rolling. At the specified compaction temperature, each pass is rolled for 3 - 4 s, about 25 round trips, so that the compaction density of the asphalt mixture reaches 100% ± 1% of the Marshall standard density; When sending the asphalt mixture sampled from the construction site to the laboratory for forming, the mixture must be placed in a heat preservation bucket to prevent its temperature from dropping, and it should be formed immediately after arriving at the laboratory. If the temperature is lower than the requirement, it can be appropriately heated to the compaction temperature and then formed with a wheel rolling forming machine. For specimens remolded after secondary heating after being completely cooled, it must be noted in the test report that the secondary heating time does not exceed 30 min;

[0048] Step 3: Demold the specimen and measure its density and void ratio;

[0049] Step 4: After the specimen is formed, it should be placed at room temperature together with the test mold for no less than 12 h. After the asphalt mixture is fully cured, the rutting test can be carried out: First, place the specimen together with the test mold on the test bench of the rutting test machine, ensure that the test wheel is located at the center of the specimen, and its traveling direction is consistent with the rolling and driving directions of the specimen; Turn on the rutting deformation automatic recorder and the test machine, and let the test wheel travel back and forth on the specimen for about 1 hour until the maximum deformation reaches 25 mm; During the test process, the recorder automatically records the deformation curve and provides detailed test data.

[0050] As shown in the following table, it is the technical requirements for the design performance indicators of this application.

[0051]

[0052] The test data results of the above Example 1 and Example 2 are as shown in the following table.

[0053]

[0054]

[0055] (1) Immersion Marshall residual stability: This index is used to evaluate the stability of asphalt mixture in water, and the technical requirement is ≥ 85%. The test results of Example 1 and Example 2 are 88.57% and 87.61% respectively, both meeting the technical requirements.

[0056] (2) Freeze-thaw splitting test residual strength ratio: This index is used to evaluate the strength retention ability of asphalt mixture after freeze-thaw cycles, and the technical requirement is ≥ 80%. The test results of Example 1 and Example 2 are 85.94% and 86.28% respectively, both meeting the technical requirements.

[0057] (3) Dynamic stability at 60°C: This index is used to evaluate the rutting resistance of asphalt mixtures at 60°C. The technical requirement is ≥ 20,000 times / mm. The test results of Example 1 and Example 2 are 21,000 times / mm and 20,800 times / mm respectively, both meeting the technical requirements.

[0058] (4) Dynamic stability at 70°C (0.7 MPa): This index is used to evaluate the rutting resistance of asphalt mixtures at 70°C under a pressure of 0.7 MPa. The technical requirement is ≥ 15,000 times / mm. The test results of Example 1 and Example 2 are 16,000 times / mm and 15,500 times / mm respectively, both meeting the technical requirements.

[0059] (5) Dynamic stability at 70°C (1.0 MPa): This index is used to evaluate the rutting resistance of asphalt mixtures at 70°C under a pressure of 1.0 MPa. The technical requirement is ≥ 10,000 times / mm. The test results of Example 1 and Example 2 are 11,200 times / mm and 10,800 times / mm respectively, both meeting the technical requirements.

[0060] (6) Bending strain of small beam at low temperature: This index is used to evaluate the deformation ability of asphalt mixtures under low temperature conditions. The technical requirement is ≥ 2500. The test results of Example 1 and Example 2 are 2600 and 2580 respectively, both meeting the technical requirements.

[0061] (7) Loss of standard flushing test: This index is used to evaluate the durability of asphalt mixtures under high-speed driving conditions. The technical requirement is ≤ 10%. The test results of Example 1 and Example 2 are 8.5% and 8.8% respectively, both meeting the technical requirements.

[0062] In order to test the high-temperature stability of URP asphalt mixtures, the rutting test was carried out according to relevant requirements. The test results are summarized in Table 1, Table 2 and Table 3 below.

[0063] Table 1 Summary Table of Rutting Test Results at 60°C

[0064]

[0065] Table 2 Summary Table of Rutting Test Results at 70°C (0.7 MPa)

[0066]

[0067] Table 2 Summary Table of Rutting Test Results at 70°C (1.0 MPa)

[0068]

[0069] As can be seen from the above Tables 1, 2, and 3, the rutting evaluation method for the URP asphalt mixture of the super heavy-duty road provided by the present invention ensures the stability and durability of the asphalt mixture under high temperature and heavy load conditions through strict test steps and performance index requirements. From the test data results of Example 1 and Example 2, the prepared asphalt mixtures can meet all technical requirements and exhibit good rutting resistance and durability. In addition, the summary table of the rutting test results further verifies the effectiveness and reliability of the present invention. Therefore, the present invention can be widely applied to the construction and maintenance of super heavy-duty roads, providing a strong guarantee for improving the service life and driving safety of roads.

[0070] Through the above embodiments, the rutting test of the present invention can provide more accurate rutting deformation data. Through the deformation curve automatically recorded by the recorder, the deformation conditions of the test piece at different stages can be analyzed in detail, so as to accurately evaluate the rutting resistance performance of the asphalt mixture. In addition, through the grounding pressure measurement experiment carried out at 70 °C, it can be ensured that the test conditions are closer to the road surface conditions under the actual heavy-duty traffic environment, thereby improving the practicability and accuracy of the evaluation system. Through the evaluation system of the present invention, a scientific basis can be provided for road design and maintenance to ensure the long-term stability and durability of the road.

[0071] In summary, the rutting evaluation method for the URP asphalt mixture of the super heavy-duty road of the present invention can provide a more accurate rutting resistance performance evaluation for road engineering, thereby guiding road design and construction to ensure the durability and driving safety of the road. At the same time, this method helps to optimize resource utilization, reduce unnecessary rework and maintenance, save natural resources and labor costs, extend the service life of the road, and reduce maintenance costs. With the continuous progress of road construction technology, the application of the present invention will have a profound impact on the field of road engineering and make a positive contribution to the sustainable development of the social economy.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An evaluation method for rutting of URP asphalt mixture for overweight roads, characterized in that It can more accurately simulate the actual environment of rutting generation on heavy-duty roads in the laboratory and expand the detection range of dynamic stability. The test method adopts the rut test method T0719-1993 in the "Test Procedures for Bitumen and Bituminous Mixtures of Highway Engineering" (JTJ052-2000); the strain monitoring equipment of the evaluation system is changed to a dial gauge, meeting the requirement of a 20% coefficient of variation for the test. When the number of cycles exceeds 6000, the measurement error will cause the coefficient of variation to exceed the range, so a dial gauge is proposed; the additional load is increased from 0.7 MPa ± 0.05 MPa to 1.0 MPa ± 0.05 MPa; based on the dynamic stability index of loading 0.7 MPa ± 0.05 MPa at a temperature of 60°C ± 0.5°C, the dynamic stability indexes of loading 0.7 MPa ± 0.05 MPa at a temperature of 70°C ± 0.5°C and loading 1 MPa ± 0.05 MPa at a temperature of 70°C ± 0.5°C are supplemented.

2. The rut evaluation method for an overweight road URP asphalt mixture according to claim 1, characterized in that The additional load is increased from 0.7 MPa ± 0.05 MPa to 1.0 MPa ± 0.05 MPa.

3. The rut evaluation method of an overweight road URP asphalt mixture according to claim 1, characterized in that The rut strain monitoring equipment for the specimen is adjusted to a dial gauge.

4. The rut evaluation method for an overweight road URP asphalt mixture according to claim 1, wherein The technical index supplements that the dynamic stability index of loading 0.7 MPa ± 0.05 MPa at a temperature of 70°C ± 0.5°C is not less than 15000 times / mm, and the dynamic stability index of loading 1 MPa ± 0.05 MPa at a temperature of 70°C ± 0.5°C is not less than 10000 times / mm.

5. The rutting evaluation method of an overweight road URP asphalt mixture according to claim 1, characterized in that Improve the credibility of the detection of mixtures with a dynamic stability greater than 6000 times / mm and expand the reliable detection range to 60000 times / mm.

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