Asphalt crack infiltration capacity evaluation method

Abstract

The invention discloses an asphalt crack infiltration capacity evaluation method. The method comprises the following steps that 1, a testing device is provided, the testing device comprises a first panel and a second panel which are fixedly arranged in parallel, and the testing device is placed in a drying oven at the temperature of 50 DEG C to be subjected to heat preservation for 2-3 hours; 2, 100 ml of asphalt is taken and heated to 180 DEG C, the testing device in the step 1 is taken out of the drying oven and vertically placed, and the asphalt is slowly poured into a gap, with the length of about 5-6 cm, between the first panel and the second panel. 3, after the asphalt is completely solidified, the distance between the lowest point of the asphalt between the first panel and the second panel and the top face of the first panel is observed, and the larger the distance is, the better the crack permeability of the asphalt is. According to the asphalt crack infiltration capacity evaluation method provided by the invention, the crack infiltration capacity of the asphalt product can be intuitively evaluated, and an intuitive and convenient evaluation method is provided for one of performance parameters of the asphalt product for pavement crack part maintenance.

Description

Technical Field

[0001] The invention relates to the technical field of highway maintenance, and in particular to a method for evaluating and testing the crack filling penetration ability of an asphalt material used for road surface crack filling. Background Art

[0002] During the use of highways, when the highway base and cross-section remain in good condition, but longitudinal and transverse cracks appear on the surface, accompanied by many fine extended cracks at the cracks, and the crack density is relatively low, using corresponding asphalt products (such as potting glue, high-viscosity and high-elastic asphalt) to repair these cracks can be a better preventive maintenance method to maintain the life cycle and performance of the highway.

[0003] Generally speaking, before maintaining the cracks, the construction site needs to be cleaned to ensure that the cracks and the surrounding areas are dry and clean. Construction is generally carried out under non-rainy conditions with a temperature above 5°C. After the asphalt product fills the cracks from the road surface, it generally needs to flow into the gaps by its own gravity until it condenses. In other words, after the asphalt product is heated to about 180°C, it can be applied to the crack surface by spraying or pouring, and then flow downward under the action of gravity until it condenses.

[0004] Pavement cracks often have irregular side walls, so there is currently no good method to evaluate the flow of different asphalts within cracks. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for evaluating the penetration capacity of asphalt cracks to solve the above-mentioned problem.

[0006] The present invention provides a method for evaluating the penetration capacity of asphalt cracks. The method comprises the following steps: Step 1, providing a test device, the test device comprising a first panel and a second panel fixedly arranged in parallel, and placing the test device in a 50° C. oven for 2-3 hours; Step 2, take 100 ml of asphalt and heat it to 180° C. Take out the test device of step 1 from the oven and place it vertically, and slowly pour the asphalt between the first panel and the second panel, at the gap of about 5 cm to 6 cm in the middle; Step 3: After the asphalt is completely solidified, observe the distance between the lowest point of the asphalt between the first panel and the second panel and the top surface of the first panel. The larger the distance, the better the crack penetration ability of the asphalt.

[0007] Preferably, in step 1, the distance between the first panel and the second panel is 3 mm or 5 mm.

[0008] Preferably, in step 1, the first panel is a glass panel, and the second panel is made of clay or yellow mud.

[0009] Preferably, in step 2, a funnel device is provided, the funnel device comprising a base portion for being placed on the first panel and the second panel, a storage portion is connected above the base portion, and gripping portions are connected on both sides of the storage portion.

[0010] Preferably, in step 2, the funnel device is placed in a 50° C. oven and kept warm for 20 minutes.

[0011] Preferably, in step 3, when the first panel is a glass panel, the distance between the lowest point of the solidified asphalt and the top surface of the first panel is measured directly through the first panel.

[0012] Preferably, in step 1, the first panel is marked with scale.

[0013] The asphalt crack penetration ability evaluation method provided by the present invention can more intuitively judge the crack penetration ability of asphalt products, thereby providing an intuitive and convenient evaluation method for one of the performance parameters of asphalt products used for partial maintenance of pavement cracks. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The following drawings are intended only to illustrate and explain the present invention, and do not limit the scope of the present invention. Figure 1 A schematic diagram of a partial three-dimensional structure principle of a testing device used in a method for evaluating asphalt crack penetration capacity according to a specific embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure principle of the second panel of an improved embodiment based on the present invention; Figure 3 for Figure 2 Schematic diagram of partial cross-section structure principle; Figure 4 A schematic diagram of the three-dimensional structure principle of a funnel device used in a method for evaluating the penetration capacity of asphalt cracks according to a specific embodiment of the present invention; Figure 5 for Figure 4 Schematic diagram of the main structure principle; Figure 6 for Figure 4 Schematic diagram of the side view structure principle; Figure 7 for Figure 6 Schematic diagram of the partial cross-section structural principle. DETAILED DESCRIPTION

[0015] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation of the present invention is now described with reference to the accompanying drawings, wherein the same components are marked with the same reference numerals.

[0016] Figure 1 FIG. 1 is a schematic diagram of a partial three-dimensional structure principle of a testing device used in a method for evaluating asphalt crack penetration according to a specific embodiment of the present invention; see Figure 1 As shown, the present invention provides a method for evaluating the penetration capacity of asphalt cracks, which comprises the following steps: Step 1, providing a testing device 100, wherein the testing device comprises a first panel 1 and a second panel 2 fixedly arranged in parallel, and placing the testing device 100 in a 50° C. oven for 2-3 hours.

[0017] The gap between the first panel 1 and the second panel 2 is used to simulate road cracks. The crack width of an actual highway road surface is usually in the range of 1mm-20mm. The present invention is mainly used to detect the flow performance of asphalt in the gap under its own gravity. Therefore, the inventor team selected 3mm and 5mm, which are relatively easy to operate and more typical of the expansion cracks in the road surface, as the spacing size between the first panel 1 and the second panel 2, that is, the gap size between the first panel 1 and the second panel 2.

[0018] That is to say, in a specific embodiment, the distance between the first panel 1 and the second panel 2 may be 3 mm or 5 mm.

[0019] The planar dimensions of the first panel 1 and the second panel 2 may be 10-12 cm in length and 8-10 cm in height, so that sufficient asphalt covering length can be left.

[0020] For the convenience of observation, the first panel 1 may be a glass plate. To ensure the structural strength, the first panel 1 may be a glass plate with a thickness greater than 8 mm.

[0021] Similarly, the second panel 2 can also be a glass plate, but in order to simulate the irregular side wall surface in a real road crack, the second panel 2 can also be made of clay or yellow mud, and the thickness can be 15-25 mm. In this way, during the drying and molding process, the inner wall surface of the second panel 2 (that is, the side facing the first panel 1) may form a number of fine cracks, thereby better simulating the situation in a real road crack.

[0022] Of course, the first panel 1 can also be made of clay or yellow mud like the second panel 2, and the thickness is also 15-25 mm. This can better simulate the actual road crack situation, but the disadvantage is that the second panel 2 must be destroyed at the end of the test to detect the distance between the lowest point of the asphalt and the top surface of the first panel 1.

[0023] See also Figure 1 As shown, the first panel 1 and the second panel 2 can be fixedly connected by bolts, which has the advantage of ensuring the stability of the connection and better ensuring the spacing distance. Of course, in order to more accurately control the spacing distance, the gap edge between the first panel 1 and the second panel 2 can also be precisely limited by setting a plurality of metal rods with a diameter of 3mm or 5mm (not shown in the figure), or at least a pair of rectangular metal rods with a side length of 3mm or 5mm (not shown in the figure).

[0024] In a specific embodiment, the inventor team processed 8 metal rods with a rectangular cross-section, a cross-sectional size of 3×5mm, and a length of 20mm to meet the requirements of laboratory 3mm gap test and 5mm gap test. Usually, in a single test, only 4 metal rods are needed to more accurately control the gap between the first panel 1 and the second panel 2.

[0025] Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure principle of the second panel of an improved embodiment based on the present invention; Figure 3 for Figure 2 Schematic diagram of the partial cross-section structure principle. Figure 2 and Figure 3 As shown, in order to better simulate the situation in real road cracks, a plurality of inner grooves 211 can be added to the inner wall surface 21 of the second panel 2', for example, the grooves can be right-angled triangles with a depth L of 1-2 mm and an angle α of 50-60 degrees. The distance H1 between the uppermost inner groove 211 and the top surface of the second panel 2' is not less than 10 mm, so as to ensure that enough asphalt flows into the gap between the first panel 1 and the second panel 2'.

[0026] The test device 100 is placed in a 50°C oven for 2-3 hours to ensure the drying of the first panel 1 and the second panel 2. In actual construction, hot air is usually used to blow away debris from cracks in the road surface and dry the moisture in the cracks. Therefore, baking the test device 100 is helpful to simulate the real construction environment.

[0027] Step 2, take 100 ml of asphalt and heat it to 180°C, take out the test device 100 of step 1 from the oven and place it vertically, and slowly pour the asphalt between the first panel 1 and the second panel 2, at the gap of about 5 cm-6 cm in the middle.

[0028] During the test, by clamping a metal container containing hot asphalt, the metal container can be reciprocated above the gap of about 5-6 cm in the middle between the first panel 1 and the second panel 2, and the hot asphalt can be slowly poured into the gap, thereby simulating the spraying or pouring operation during actual construction.

[0029] Usually, hot asphalt at room temperature will basically lose fluidity within 2 minutes. During this process, when the asphalt is deposited on the top of the first panel 1 and the second panel 2 and no longer moves downward, you can stop and wait to see if the asphalt continues to fall in the gap. If it continues to deposit, it means that the asphalt in the gap has stopped flowing downward. If the deposition is eliminated, you can continue to pour the asphalt until the asphalt in the container loses fluidity.

[0030] This operation requires a high level of operator proficiency and is more eye- and labor-intensive.

[0031] Figure 4 A schematic diagram of the three-dimensional structure principle of a funnel device used in a method for evaluating the penetration capacity of asphalt cracks according to a specific embodiment of the present invention; Figure 5 for Figure 4 Schematic diagram of the main structure principle; Figure 6 for Figure 4 Schematic diagram of the side view structure principle; Figure 7 for Figure 6 Schematic diagram of partial cross-section structure principle. Figures 4 to 7 As shown, in order to improve the test efficiency, the inventor team provides a funnel device 200, which includes a base portion 3 for being placed on the first panel 1 and the second panel 2, a storage portion 4 is connected above the base portion 3, and gripping portions 5 are connected on both sides of the storage portion 4.

[0032] The funnel device 200 can be made of a metal plate with a thickness of 2-3 mm (such as a galvanized plate or a stainless steel plate). The length L1 of the funnel device 200 can be 6 cm, the height H of the base portion 3 can be 15 mm, and the width W of the hollow gap of the base portion 3 can be 2-3 mm larger than the gap size between the first panel 1 and the second panel 2. This can ensure the alignment and coverage of the gap between the first panel 1 and the second panel 2. For example, when the gap size between the first panel 1 and the second panel 2 is 3 mm, the width W of the hollow gap of the base portion 3 can be 5-6 mm. When the gap size between the first panel 1 and the second panel 2 is 5 mm, the width W of the hollow gap of the base portion 3 can be 7-8 mm.

[0033] In the test, the funnel device 200 can also be placed in a 50°C oven for about 20 minutes. Then, after taking the test device 100 of step 1 out of the oven and placing it vertically, one person can wrap the holding portion 5 with a towel and place the funnel device 200 on the test device 100, and ensure that the hollow gap of the base portion 3 covers the gap between the first panel 1 and the second panel 2. Then another person can pour all the hot asphalt into the storage portion 4, so that the asphalt itself can flow to the gap between the first panel 1 and the second panel 2 under the action of gravity. In this way, after the asphalt starts to flow, the person holding the funnel device 200 does not need to use special force, and only needs to basically stabilize the funnel device 200. This greatly reduces the difficulty of the test operation.

[0034] Step 3: After the asphalt is completely solidified, observe the distance between the lowest point of the asphalt between the first panel 1 and the second panel 2 and the top surface of the first panel 1. The larger the distance, the better the crack penetration ability of the asphalt.

[0035] When the first panel 1 is a glass plate, the distance between the lowest point of the solidified asphalt and the top surface of the first panel 1 can be directly measured through the first panel 1. Of course, the first panel 1 can also be directly marked with a scale, which makes it easier to intuitively obtain the distance data between the lowest point of the solidified asphalt and the top surface of the first panel 1.

[0036] In this case, when the inventors' team used No. 70 base asphalt for the test, the average distance data of three measurements was 3.4 cm. Figure 2 and Figure 3 When the structure is used, the average distance data of three measurements is 3.1cm.

[0037] When the first panel 1 and the second panel 2 are both made of clay or yellow mud, the second panel 2 must be destroyed to measure the distance between the lowest point of the asphalt and the top surface of the first panel 1 .

[0038] In this case, when the inventors' team used No. 70 base asphalt for the test, the average distance data of three measurements was 2.9 cm. Figure 2 and Figure 3 When the structure is used, the average distance data of three measurements is 2.5cm.

[0039] Therefore, the test data of the above-mentioned No. 70 base asphalt can be used as a comparison parameter to compare the distance data of different asphalt products, so as to evaluate the crack penetration ability of the asphalt products.

[0040] When the funnel device 200 is used in step 2, considering that the hot asphalt has basically no fluidity within 2 minutes, therefore, when the asphalt in the storage portion 4 is in a gel state, a cutter can be used to cut the asphalt under the funnel device 200 along the top surface of the first panel 1, so that the funnel device 200 can be removed. At this time, it is also convenient to pick out excess asphalt and clean the funnel device 200.

[0041] The asphalt crack penetration ability evaluation method provided by the present invention can more intuitively judge the crack penetration ability of asphalt products, thereby providing an intuitive and convenient evaluation method for one of the performance parameters of asphalt products used for partial maintenance of pavement cracks.

[0042] Those skilled in the art should understand that although the present invention is described in the form of multiple embodiments, not every embodiment includes only one independent technical solution. Such description in the specification is only for the sake of clarity. Those skilled in the art should understand the specification as a whole and regard the technical solutions involved in each embodiment as being able to be combined into different embodiments to understand the scope of protection of the present invention.

[0043] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes, modifications and combinations made by any person skilled in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A method for evaluating the penetration capacity of asphalt cracks. It is characterized by: It includes the following steps, Step 1, providing a test device, the test device comprising a first panel and a second panel fixedly arranged in parallel, and placing the test device in a 50° C. oven for 2-3 hours; Step 2, take 100 ml of asphalt and heat it to 180° C. Take out the test device of step 1 from the oven and place it vertically, and slowly pour the asphalt between the first panel and the second panel, at the gap of about 5 cm to 6 cm in the middle; Step 3: After the asphalt is completely solidified, observe the distance between the lowest point of the asphalt between the first panel and the second panel and the top surface of the first panel. The larger the distance, the better the crack penetration ability of the asphalt.

2. The method according to claim 1, characterized in that: In step 1, the distance between the first panel and the second panel is 3 mm or 5 mm.

3. The method according to claim 1, characterized in that: In step 1, the first panel is a glass panel, and the second panel is made of clay or yellow mud.

4. The method according to claim 1, characterized in that: In step 2, a funnel device is provided, wherein the funnel device comprises a base portion for being placed on the first panel and the second panel, a storage portion is connected above the base portion, and gripping portions are connected on both sides of the storage portion.

5. The method according to claim 4, characterized in that: In step 2, the funnel device is placed in a 50° C. oven for 20 minutes.

6. The method according to claim 1, characterized in that: In step 3, when the first panel is a glass panel, the distance between the lowest point of the solidified asphalt and the top surface of the first panel is measured directly through the first panel.

7. The method according to claim 6, characterized in that: In step 1, the first panel is marked with scale.

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