Water boiling method-based quantitative evaluation method for adhesion of aggregate

Abstract

The invention discloses a quantitative evaluation method for the adhesion of aggregate based on a water boiling method, and aims to solve the technical problem that the adhesion performance of asphalt and aggregate tested by the water boiling method can only be evaluated qualitatively and cannot be quantified. The quantitative evaluation method comprises the following steps: 1, carrying out a water boiling test on the adhesion performance of the asphalt and the aggregate by adopting a water boiling method; 2, shooting by adopting an industrial camera to respectively obtain images of four side surfaces coated with the asphalt aggregate and images of four side surfaces of the boiled asphalt aggregate; 3, unifying the background color of the side image, and then eliminating a reflective area on the surface of the aggregate through a two-stage reflective removal method to obtain a reflective-removed aggregate image; and 4, calculating the asphalt peeling rate on the surface of the aggregate by calculating the areas of the four side surfaces of the aggregate and the asphalt peeling area. According to the method, the boiling method and the image processing method are combined, the highlight area of the image is eliminated through the light reflection removing algorithm, the asphalt peeling area can be accurately calculated through the image method, and therefore the adhesion grade of the aggregate can be accurately judged.

Description

Technical Field

[0001] The invention belongs to the field of asphalt-aggregate adhesion evaluation, and in particular relates to a quantitative evaluation method for aggregate adhesion based on a water boiling method. Background Art

[0002] The adhesion performance between asphalt and aggregate is one of the key indicators to ensure the resistance of asphalt mixture to water damage and durability. At present, the "Test Procedure for Asphalt Mixtures in Highway Engineering" (JTG E20-2011) proposes to use the boiling method for adhesion testing. The boiling method is to place the aggregate with asphalt on the surface in "slightly boiling" water for a period of time, and then observe the peeling of asphalt on the stone surface with the naked eye to judge the adhesion performance of asphalt and aggregate. This test result is evaluated by the "naked eye", which can only make a qualitative evaluation of asphalt-aggregate adhesion, and there is no specific analysis indicator. Summary of the invention

[0003] The present invention aims to solve the technical problem that the adhesion performance of asphalt and aggregate tested by the water boiling method can only be evaluated qualitatively but not quantified, and provides a quantitative evaluation method for aggregate adhesion based on the water boiling method.

[0004] The quantitative evaluation method of aggregate adhesion based on the water boiling method of the present invention is implemented according to the following steps:

[0005] 1. Aggregate boiling test:

[0006] The aggregate particles are immersed in heated asphalt so that the asphalt completely covers the aggregate particles to obtain asphalt-coated aggregates, and then a boiling test is conducted on the adhesion performance of asphalt and aggregates by a boiling method to obtain boiled asphalt aggregates;

[0007] 2. Take four side images of the aggregate:

[0008] An industrial camera was used to obtain four side images of the coated asphalt aggregate and four side images of the boiled asphalt aggregate;

[0009] 3. Remove background and reflection from aggregate images:

[0010] The four side images of the coated asphalt aggregate and the four side images of the boiled asphalt aggregate were processed with a unified background color using image processing software, and then the reflective area on the aggregate surface was eliminated by a two-stage de-reflection method to obtain the de-reflected aggregate image.

[0011] The process of the two-stage de-glare method is as follows:

[0012] The first stage: grayscale processing is performed on the side image of the aggregate after the background color is unified. The following formula (1) is used to grayscale process the pixels of each side image to obtain the grayscale processed image;

[0013] c E =0.2989c R +0.5870c G +0.1140c B (1)

[0014] Where: c R ,c G and c B are the red channel intensity value, green channel intensity value and blue channel intensity value of each pixel, respectively, E Represents the gray value of each pixel;

[0015] The intensity at the 95th percentile is used as the highlight judgment, and the value r of the 95th percentile of the green intensity is calculated respectively. GE and the 95% quantile value of blue intensity r BE ;

[0016]

[0017] Where P 95 (c G ) is the 95% green channel intensity value, P 95 (c E ) is the 95% grayscale image intensity value, P 95 (c B ) is the 95th percentile blue channel intensity value;

[0018] Then the highlight pixel position is determined by the following formula (3), and the grayscale value of the pixel position x is c E (x), the green channel intensity value of pixel position x is c G (x), the blue channel intensity value of pixel position x is c B (x), the red channel intensity value of pixel position x is c R (x), T1 is the first threshold, and the pixel position x that satisfies equation (3) is the highlight pixel position;

[0019] c G (x)>r GE ·T1 and c B (x)>r BE ·T1 and c E (x)>T1 (3)

[0020] The second stage: median filtering is performed on the side image of the aggregate after the background color is unified. After median filtering, the red channel intensity value of each pixel at position x is The green channel intensity value is and the blue channel intensity value is The maximum value of the red channel intensity ratio, the green channel intensity ratio and the blue channel intensity ratio before and after the median filtering is calculated according to the following formula (4);

[0021]

[0022] Set the second threshold When ε max (x) The pixel position x that satisfies equation (5) is the highlight pixel position;

[0023]

[0024] After the highlight detection in the first and second stages, the highlight pixels that satisfy formula (3) and formula (5) (respectively) are all highlight areas. The highlight areas are eliminated and smoothing is performed using neighboring pixels to obtain a de-reflected aggregate image.

[0025] 4. Calculate the spalling rate on each side of the aggregate and determine the adhesion grade:

[0026] The de-reflected aggregate image is binarized to obtain the black-and-white images of the asphalt-coated aggregate on the four sides and the black-and-white images of the asphalt-coated aggregate after boiling on the four sides. By counting the number of black pixels n in the black-and-white images, the asphalt-coated aggregate areas of the four sides are calculated as S and S, respectively. c1 , S c2 , S c3 and S c4 Calculate the asphalt peeling area of ​​the asphalt-coated aggregate after boiling on the four sides in the black and white picture respectively. p1 , S p2 , S p3 and S p4 , the asphalt stripping rate pr of the aggregate surface is calculated according to the following formula (6);

[0027]

[0028] The asphalt stripping rate pr of the aggregate surface is obtained by calculation, thereby determining the aggregate adhesion grade.

[0029] The present invention combines the water boiling method and the image processing method to evaluate the asphalt-aggregate adhesion. The highlight area of ​​the image is eliminated by a de-reflection algorithm to improve the calculation accuracy of the asphalt spalling area. At the same time, the asphalt spalling area can be accurately calculated by the image method, thereby being able to (relatively) accurately judge the adhesion level of the aggregate and reduce the error of human eye judgment.

[0030] The quantitative evaluation method of aggregate adhesion based on the water boiling method of the present invention has the following beneficial effects:

[0031] (1) It avoids the subjectivity of the current “boiling method” for evaluating aggregate adhesion;

[0032] (2) The present invention optimizes the image processing method, which can more accurately calculate the asphalt stripping rate of the aggregate surface, thereby accurately evaluating the adhesion of the aggregate;

[0033] (3) This test method reduces test errors by unifying the background and eliminating reflection algorithms. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a flow chart of the quantitative evaluation method of aggregate adhesion based on the water boiling method of the present invention;

[0035] Figure 2 This is an experimental photo of the asphalt aggregate after drying and boiling in the embodiment;

[0036] Figure 3 The images are four sides (Figures a-d) of the tuff aggregate under the long-term aged asphalt after water boiling in step 2 of the embodiment;

[0037] Figure 4 The four side views (Figure a-Figure d) of the boiled asphalt aggregate in step 3 of the embodiment are images processed with a uniform background color;

[0038] Figure 5 for Figure 4 a Pixel histogram before and after uniform background and de-reflection processing;

[0039] Figure 6 for Figure 4 b Pixel histogram before and after uniform background and de-reflection processing;

[0040] Figure 7 for Figure 4 c Pixel histogram before and after uniform background and de-reflection processing;

[0041] Figure 8 for Figure 4 d Pixel histogram before and after uniform background and de-reflection processing;

[0042] Fig. 9 These are four side images of the asphalt-coated aggregate after binarization in step 4 of the embodiment and four side images of the asphalt aggregate after boiling. DETAILED DESCRIPTION

[0043] Specific implementation method 1: The quantitative evaluation method of aggregate adhesion based on the water boiling method in this implementation method is implemented according to the following steps:

[0044] 1. Aggregate boiling test:

[0045] The aggregate particles are immersed in heated asphalt so that the asphalt completely covers the aggregate particles to obtain asphalt-coated aggregates, and then a boiling test is conducted on the adhesion performance of asphalt and aggregates by a boiling method to obtain boiled asphalt aggregates;

[0046] 2. Take four side images of the aggregate:

[0047] An industrial camera was used to obtain four side images of the coated asphalt aggregate and four side images of the boiled asphalt aggregate;

[0048] 3. Remove background and reflection from aggregate images:

[0049] The four side images of the coated asphalt aggregate and the four side images of the boiled asphalt aggregate were processed with a unified background color using image processing software, and then the reflective area on the aggregate surface was eliminated by a two-stage de-reflection method to obtain the de-reflected aggregate image.

[0050] The process of the two-stage de-glare method is as follows:

[0051] The first stage: grayscale processing is performed on the side image of the aggregate after the background color is unified. The following formula (1) is used to grayscale process the pixels of each side image to obtain the grayscale processed image;

[0052] c E =0.2989c R +0.5870c G +0.1140c B (1)

[0053] Where: c R ,c G and c B are the red channel intensity value, green channel intensity value and blue channel intensity value of each pixel, respectively, E Represents the gray value of each pixel;

[0054] The intensity at the 95th percentile is used as the highlight judgment, and the value r of the 95th percentile of the green intensity is calculated respectively. GE and the 95% quantile value of blue intensity r BE ;

[0055]

[0056] Where P 95 (c G ) is the 95% green channel intensity value, P 95 (c E ) is the 95% grayscale image intensity value, P 95 (c B) is the 95th percentile blue channel intensity value;

[0057] Then the highlight pixel position is determined by the following formula (3), and the grayscale value of the pixel position x is c E (x), the green channel intensity value of pixel position x is c G (x), the blue channel intensity value of pixel position x is c B (x), the red channel intensity value of pixel position x is c R (x), T1 is the first threshold, and the pixel position x that satisfies equation (3) is the highlight pixel position;

[0058] c G (x)>r GE ·T1 and c B (x)>r BE ·T1 and c E (x)>T1 (3)

[0059] The second stage: median filtering is performed on the side image of the aggregate after the background color is unified. After median filtering, the red channel intensity value of each pixel at position x is The green channel intensity value is and the blue channel intensity value is The maximum value of the red channel intensity ratio, the green channel intensity ratio and the blue channel intensity ratio before and after the median filtering is calculated according to the following formula (4);

[0060]

[0061] Set the second threshold When ε max (x) The pixel position x that satisfies equation (5) is the highlight pixel position;

[0062]

[0063] After the highlight detection in the first and second stages, the highlight pixels that satisfy formula (3) and formula (5) are all highlight areas. The highlight areas are eliminated and smoothing is performed using neighboring pixels to obtain a de-reflected aggregate image.

[0064] 4. Calculate the spalling rate on each side of the aggregate and determine the adhesion grade:

[0065] The de-reflected aggregate image is binarized to obtain the black-and-white images of the asphalt-coated aggregate on the four sides and the black-and-white images of the asphalt-coated aggregate after boiling on the four sides. By counting the number of black pixels n in the black-and-white images, the asphalt-coated aggregate areas of the four sides are calculated as S and S, respectively. c1 , S c2 , Sc3 and S c4 Calculate the asphalt peeling area of ​​the asphalt-coated aggregate after boiling on the four sides in the black and white picture respectively. p1 , S p2 , S p3 and S p4 , the asphalt stripping rate pr of the aggregate surface is calculated according to the following formula (6);

[0066]

[0067] The asphalt stripping rate pr of the aggregate surface is obtained by calculation, thereby determining the aggregate adhesion grade.

[0068] The aggregate boiling method in step 1 of this embodiment is in accordance with the "Test Procedures for Asphalt Mixtures for Highway Engineering" (JTGE20-2011), which proposes the use of the boiling method for adhesion testing.

[0069] This embodiment P 95 (c G ) is the 95% green channel intensity value, which means that the green channel intensity values ​​of all pixels in the image are arranged from low to high, and the 95% (high value) green channel intensity value is selected as P 95 (c G ).

[0070] Specific implementation method 2: This implementation method is different from the specific implementation method 1 in that the water boiling method test process in step 1 is as follows:

[0071] a. Use a thin wire to cover the middle of the aggregate particles, place them in an oven at 100-110°C for heating, immerse the heated aggregate particles in heated asphalt, then hang the aggregate on a test frame, cool it at room temperature, and obtain asphalt-coated aggregate;

[0072] b. Immerse the coated asphalt aggregate in a beaker filled with boiling water, take out the aggregate from the boiling water, and then put it into a container filled with normal temperature water to cool to room temperature to obtain boiled asphalt aggregate.

[0073] Specific implementation method three: The difference between this implementation method and specific implementation method two is that in step a, the aggregate is placed in an oven at 100-110° C. for heating treatment for 1 hour.

[0074] Specific implementation method 4: This implementation method is different from specific implementation method 2 in that the boiling time in step b is 3 minutes.

[0075] Specific implementation method 5: The difference between this implementation method and specific implementation methods 1 to 4 is that the image processing software described in step 3 adopts Photoshop software.

[0076] Specific implementation method six: This implementation method is different from any one of specific implementation methods one to five in that in step three, the four side images of the coated asphalt aggregate and the four side images of the boiled asphalt aggregate are respectively processed with a unified background color, and the background color is set to purple.

[0077] Specific implementation method 7: The difference between this implementation method and any one of specific implementation methods 1 to 6 is that the value of the first threshold value T1 in step 3 is 220.

[0078] Specific implementation eight: The difference between this implementation and any one of specific implementations one to seven is that in step four, when the asphalt stripping rate pr=0, the adhesion level=5; when the asphalt stripping rate 0<pr<10%, the adhesion level=4.

[0079] Specific implementation method 9: The difference between this implementation method and any one of specific implementation methods 1 to 7 is that in step 4, when the asphalt stripping rate is 10%≦pr<30%, the adhesion level = 3; when the asphalt stripping rate is 30%≦pr<100%, the adhesion level = 2.

[0080] Specific implementation method ten: The difference between this implementation method and any one of specific implementation methods one to seven is that in step four, when the asphalt stripping rate = 100%, the adhesion level = 1.

[0081] Embodiment 1: The quantitative evaluation method of aggregate adhesion based on the water boiling method in this embodiment is implemented according to the following steps:

[0082] 1. Aggregate boiling test:

[0083] Four types of lithologic aggregates (basalt, diabase, limestone and tuff) were selected as original samples and long-term aged No. 70 asphalt. The adhesion performance of asphalt and aggregate was tested by boiling method. Aggregates were tied in the middle with fine wires one by one and heated in an oven at 105℃ for 1h. Then, the heated aggregates were immersed in the heated asphalt one by one and gently taken out so that the aggregate particles were completely covered by the asphalt film. Then, the aggregate particles covered with asphalt were hung on the test frame (such as Figure 2 As shown), excess asphalt is drained off, and the asphalt is cooled at room temperature for 15 minutes to obtain coated asphalt aggregate, and then the coated asphalt aggregate is immersed in a beaker filled with boiling water and boiled for 3 minutes, the aggregate is taken out of the water, and then placed in a container filled with normal temperature water to cool to room temperature, and then dried to obtain boiled asphalt aggregate;

[0084] 2. Take four side images of the aggregate:

[0085] An industrial camera was used to obtain four side images of the coated asphalt aggregate and four side images of the boiled asphalt aggregate;

[0086] 3. Remove background and reflection from aggregate images:

[0087] The four side images of the coated asphalt aggregate and the four side images of the boiled asphalt aggregate were processed with a unified background color using image processing software, and then the reflective area on the aggregate surface was eliminated by a two-stage de-reflection method to obtain the de-reflected aggregate image.

[0088] The process of the two-stage de-glare method is as follows:

[0089] The first stage: grayscale processing is performed on the side image of the aggregate after the background color is unified. The following formula (1) is used to grayscale process the pixels of each side image to obtain the grayscale processed image;

[0090] c E =0.2989c R +0.5870c G +0.1140c B (1)

[0091] Where: c R ,c G and c B are the red channel intensity value, green channel intensity value and blue channel intensity value of each pixel, respectively, E Represents the gray value of each pixel;

[0092] The intensity at the 95th percentile is used as the highlight judgment, and the value r of the 95th percentile of the green intensity is calculated respectively. GE and the 95% quantile value of blue intensity r BE ;

[0093]

[0094] Where P 95 (c G ) is the 95% green channel intensity value, P 95 (c E ) is the 95% grayscale image intensity value, P 95 (c B ) is the 95th percentile blue channel intensity value;

[0095] Then the highlight pixel position is determined by the following formula (3), and the grayscale value of the pixel position x is c E (x), the green channel intensity value of pixel position x is c G (x), the blue channel intensity value of pixel position x is c B (x), the red channel intensity value of pixel position x is c R (x), T1 is the first threshold value, T1 is 220, when the pixel position x that satisfies formula (3) is the highlight pixel position;

[0096] c G (x)>r GE ·T1 and c B (x)>r BE ·T1 and c E (x)>T1 (3)

[0097] The second stage: median filtering is performed on the side image of the aggregate after the background color is unified. After median filtering, the red channel intensity value of each pixel at position x is The green channel intensity value is and the blue channel intensity value is The maximum value of the red channel intensity ratio, the green channel intensity ratio and the blue channel intensity ratio before and after the median filtering is calculated according to the following formula (4);

[0098]

[0099] Set the second threshold When ε max (x) The pixel position x that satisfies equation (5) is the highlight pixel position;

[0100]

[0101] After the highlight detection in the first and second stages, the highlight pixels that satisfy formula (3) or formula (5) are all highlight areas. The highlight areas are eliminated and smoothing is performed using neighboring pixels to obtain a de-reflected aggregate image.

[0102] 4. Calculate the spalling rate on each side of the aggregate and determine the adhesion grade:

[0103] The de-reflected aggregate image was binarized and the background color was removed to obtain the black and white images of the asphalt-coated aggregate on the four sides and the black and white images of the asphalt-coated aggregate after boiling on the four sides. The number of black pixels n in the black and white image was counted and the image size (l×b) and the total number of pixels were used to calculate (n p ×n l ), calculate the area of ​​aggregate fully coated with asphalt S c and water-boiled asphalt coated aggregate area S l , (the area calculation method is shown in formula (6)), the area of ​​asphalt peeling S p Calculated by formula (7);

[0104]

[0105] S p =S c -S l (7)

[0106] The calculated asphalt-coated aggregate areas on the four sides are S c1 , S c2 , S c3 and S c4 The areas of asphalt peeling in the black and white images of the asphalt-coated aggregate after boiling on the four sides are S p1 , S p2 , S p3 and S p4 , the asphalt stripping rate pr of the aggregate surface is calculated according to the following formula (8);

[0107]

[0108] The asphalt stripping rate pr of the aggregate surface is obtained by calculation, thereby determining the aggregate adhesion grade.

[0109] This embodiment unifies the background of the aggregate as follows Figure 4 As shown in the figure. The pixel histogram before and after image processing is analyzed using Matlab program. It can be seen from the figure that the pixel span of the original image is large. If no processing is done, it is easy to identify the image (not the asphalt covered part or the peeling part) as the asphalt covered area or the peeling part. After using a unified background, the pixel frequency of a certain small section is very high, that is, the background image pixel, which can be easily identified as the background. This background removal processing method can improve the recognition accuracy. At the same time, it can be seen that the reflective part of the aggregate surface is eliminated, which can also improve the recognition accuracy.

[0110] In this embodiment, the aggregate image is processed into black and white by adjusting the image binarization threshold, and the area S of each image is calculated respectively. c and S l Then the asphalt peeling area S of the aggregate surface is calculated using the following formula: p The area of ​​each part is shown in Table 2. The calculated S c Area 22.35cm 2 , asphalt peeling off aggregate surface S p Area 2.63cm 2 , the asphalt peeling rate of the aggregate surface is calculated to be 11.8%, and the adhesion grade of the aggregate is determined to be grade 3 with reference to the standard in Table 1. The comparison of the image calculation results and the test results of experienced testers using the water boiling method between several lithologic aggregates and different asphalts tested by this method is shown in Table 3. It can be seen from the table that the results of the improved evaluation method are roughly the same as the empirical evaluation results, but for the test results at the boundary of the adhesion grading index, the modified evaluation method of this embodiment is more accurate.

[0111] Table 1 Adhesion grade of asphalt and aggregate

[0112]

[0113]

[0114] Table 2 Area of ​​each figure (cm 2 )

[0115] picture <![CDATA[S c ]]> <![CDATA[S l ]]> <![CDATA[S p ]]> Figure 4 a 6.1 5 1.1 Figure 4 b 5.3 4.94 0.36 Figure 4 c 5.27 4.37 0.9 Figure 4 d 5.68 5.41 0.27

[0116] Table 3 Improved evaluation method and empirical evaluation results

[0117]

Claims

1. A quantitative evaluation method for aggregate adhesion based on the water boiling method, characterized in that The quantitative evaluation method is implemented according to the following steps:

1. Aggregate boiling test: The aggregate particles are immersed in heated asphalt so that the asphalt completely covers the aggregate particles to obtain asphalt-coated aggregates, and then a boiling test is conducted on the adhesion performance of asphalt and aggregates by a boiling method to obtain boiled asphalt aggregates; 2. Take four side images of the aggregate: An industrial camera was used to obtain four side images of the coated asphalt aggregate and four side images of the boiled asphalt aggregate; 3. Remove background and reflection from aggregate images: The four side images of the coated asphalt aggregate and the four side images of the boiled asphalt aggregate were processed with a unified background color using image processing software, and then the reflective area on the aggregate surface was eliminated by a two-stage de-reflection method to obtain the de-reflected aggregate image. The process of the two-stage de-glare method is as follows: The first stage: grayscale processing is performed on the side image of the aggregate after the background color is unified. The following formula (1) is used to grayscale process the pixels of each side image to obtain the grayscale processed image; c E =0.2989c R +0.5870c G +0.1140c B (1) Where: c R ,c G and c B are the red channel intensity value, green channel intensity value and blue channel intensity value of each pixel, respectively, E Represents the gray value of each pixel; The intensity at the 95th percentile is used as the highlight judgment, and the value r of the 95th percentile of the green intensity is calculated respectively. GE and the 95% quantile value of blue intensity r BE ; Where P 95 (c G ) is the 95% green channel intensity value, P 95 (c E ) is the 95% grayscale image intensity value, P 95 (c B ) is the 95th percentile blue channel intensity value; Then the highlight pixel position is determined by the following formula (3), and the grayscale value of the pixel position x is c E (x), the green channel intensity value of pixel position x is c G (x), the blue channel intensity value of pixel position x is c B (x), the red channel intensity value of pixel position x is c R (x), T1 is the first threshold, and the pixel position x that satisfies equation (3) is the highlight pixel position; c G (x) > r GE · T1 and c B (x) > r BE · T1 and c E (x) > T1 (3) The second stage: median filtering is performed on the side image of the aggregate after the background color is unified. After median filtering, the red channel intensity value of each pixel at position x is The green channel intensity value is and the blue channel intensity value is The maximum value of the red channel intensity ratio, the green channel intensity ratio and the blue channel intensity ratio before and after the median filtering is calculated according to the following formula (4); Set the second threshold When ε max (x) The pixel position x that satisfies equation (5) is the highlight pixel position; After the highlight detection in the first and second stages, the highlight pixels that satisfy formula (3) and formula (5) are all highlight areas. The highlight areas are eliminated and smoothing is performed using neighboring pixels to obtain a de-reflected aggregate image.

4. Calculate the spalling rate on each side of the aggregate and determine the adhesion grade: The de-reflected aggregate image is binarized to obtain the black-and-white images of the asphalt-coated aggregate on the four sides and the black-and-white images of the asphalt-coated aggregate after boiling on the four sides. By counting the number of black pixels n in the black-and-white images, the asphalt-coated aggregate areas of the four sides are calculated as S and S, respectively. c1 , S c2 , S c3 and S c4 Calculate the asphalt peeling area of ​​the asphalt-coated aggregate after boiling on the four sides in the black and white picture respectively. p1 , S p2 , S p3 and S p4 , the asphalt stripping rate pr of the aggregate surface is calculated according to the following formula (6); The asphalt stripping rate pr of the aggregate surface is obtained by calculation, thereby determining the aggregate adhesion grade.

2. The quantitative evaluation method for aggregate adhesion based on the water boiling method according to claim 1 is characterized in that The boiling test process in step 1 is as follows: a. Use a thin wire to cover the middle of the aggregate particles, place them in an oven at 100-110°C for heating, immerse the heated aggregate particles in heated asphalt, then hang the aggregate on a test frame, cool it at room temperature, and obtain asphalt-coated aggregate; b. Immerse the coated asphalt aggregate in a beaker filled with boiling water, take out the aggregate from the boiling water, and then put it into a container filled with normal temperature water to cool to room temperature to obtain boiled asphalt aggregate.

3. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 2 is characterized in that In step a, the aggregate is placed in an oven at 100-110° C. and heated for 1 hour.

4. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 2, characterized in that The boiling time in step b is 3 minutes.

5. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 1, characterized in that The image processing software described in step 3 adopts Photoshop software.

6. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 1, characterized in that In step 3, the four side images of the coated asphalt aggregate and the four side images of the boiled asphalt aggregate are respectively processed with a unified background color, and the background color is set to purple.

7. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 1, characterized in that The value of the first threshold T1 in step three is 220.

8. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 1, characterized in that In step 4, when the asphalt stripping rate pr=0, the adhesion level=5; when the asphalt stripping rate 0<pr<10%, the adhesion level=4.

9. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 1, characterized in that In step 4, when the asphalt stripping rate is 10%≦pr<30%, the adhesion level = 3; when the asphalt stripping rate is 30%≦pr<100%, the adhesion level = 2.

10. The quantitative evaluation method of aggregate adhesion based on the water boiling method according to claim 1, characterized in that In step 4, when the asphalt stripping rate = 100%, the adhesion level = 1.

Images