CN114018969A - Method for quantitatively evaluating anti-freezing performance of salt-storage asphalt concrete pavement - Google Patents
Method for quantitatively evaluating anti-freezing performance of salt-storage asphalt concrete pavement Download PDFInfo
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- CN114018969A CN114018969A CN202111306478.3A CN202111306478A CN114018969A CN 114018969 A CN114018969 A CN 114018969A CN 202111306478 A CN202111306478 A CN 202111306478A CN 114018969 A CN114018969 A CN 114018969A
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- 238000007710 freezing Methods 0.000 title claims abstract description 45
- 238000003860 storage Methods 0.000 title claims abstract description 38
- 239000011384 asphalt concrete Substances 0.000 title claims abstract description 36
- 238000000034 method Methods 0.000 title claims abstract description 20
- 238000012360 testing method Methods 0.000 claims abstract description 52
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 25
- 238000002844 melting Methods 0.000 claims abstract description 22
- 238000005507 spraying Methods 0.000 claims abstract description 20
- 230000008018 melting Effects 0.000 claims abstract description 18
- 230000011218 segmentation Effects 0.000 claims abstract description 15
- 238000009833 condensation Methods 0.000 claims abstract description 12
- 230000000694 effects Effects 0.000 claims abstract description 12
- 230000005494 condensation Effects 0.000 claims abstract description 11
- 238000004321 preservation Methods 0.000 claims abstract description 9
- 238000012545 processing Methods 0.000 claims abstract description 8
- 238000001931 thermography Methods 0.000 claims abstract description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims 5
- 239000011780 sodium chloride Substances 0.000 claims 5
- 238000011158 quantitative evaluation Methods 0.000 abstract description 4
- 150000003839 salts Chemical class 0.000 description 7
- 239000010426 asphalt Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 230000008014 freezing Effects 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 238000001559 infrared map Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 239000011232 storage material Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N25/00—Investigating or analyzing materials by the use of thermal means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/28—Measuring arrangements characterised by the use of optical techniques for measuring areas
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- Life Sciences & Earth Sciences (AREA)
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- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
Abstract
The invention discloses a quantitative evaluation method for the anti-freezing performance of a salt-storage asphalt concrete pavement, which comprises the following steps: s1: preparing a salt-storage asphalt concrete pavement test piece, and placing the test piece in a thermostat simulating a low-temperature condition in winter for heat preservation treatment; s2: performing water spraying treatment on the test piece, continuously placing the test piece in the thermostat for low-temperature storage after water spraying is finished, observing and shooting the ice condensation condition of the surface of the test piece, and shooting by adopting an infrared thermal imaging camera during shooting to obtain an infrared image of the ice condensation on the surface of the test piece; s3: according to the temperature of the ice-freezing infrared image, carrying out segmentation treatment on the ice-freezing infrared image; s4: and calculating the area ratio of the ice melting part on the surface of the test piece according to the segmentation processing result, and taking the area ratio as an index for evaluating the pavement anti-freezing effect of the test piece. The method can quantitatively analyze the anti-icing performance of the salt-storage asphalt concrete pavement and more intuitively obtain the anti-icing effect of the salt-storage asphalt concrete pavement.
Description
Technical Field
The invention relates to the technical field of salt storage asphalt concrete pavement detection, in particular to a quantitative evaluation method for the anti-freezing performance of a salt storage asphalt concrete pavement.
Background
The Chinese territory is wide, the climatic condition is complicated, and the area of the snowfall icing territory is wide in winter. Particularly, in the severe cold mountainous areas in western and Sichuan, the problem of snow accumulation and icing on the road surface or the bridge deck is severe, even traffic needs to be closed, and the road transportation efficiency and the traffic safety are seriously influenced. The traditional method for removing the accumulated snow on the road surface mainly adopts passive anti-icing technologies such as manual and mechanical shoveling or spreading of snow melting salt, and the like, so that the labor intensity is high, the use effect is lagged, and the snow melting salt also causes serious damage to road structures, vegetation and ecological environment.
The salt-storage asphalt concrete is prepared by uniformly mixing an anti-freezing agent with a slow release performance in the production process of an asphalt mixture, and mixing and constructing to form an asphalt pavement with an anti-freezing function. When the asphalt pavement meets rainy, snowy and frozen weather, the effective components of the anti-icing agent in the asphalt pavement are gradually released to the road surface to melt ice and snow, so that the aim of actively melting snow and ice is fulfilled. The ice melting performance of the salt storage asphalt concrete is a key factor for evaluating the anti-freezing effectiveness of the salt storage asphalt concrete. At present, no reasonable test method is available for quantitatively estimating or evaluating the ice and snow melting effect of the asphalt pavement.
Disclosure of Invention
Aiming at the problems, the invention aims to provide a quantitative evaluation method for the anti-freezing performance of a salt-storage asphalt concrete pavement.
The technical scheme of the invention is as follows:
a method for quantitatively evaluating the anti-freezing performance of a salt-storage asphalt concrete pavement comprises the following steps:
s1: preparing a salt-storage asphalt concrete pavement test piece, and placing the test piece in a thermostat simulating a low-temperature condition in winter for heat preservation treatment;
s2: performing water spraying treatment on the test piece, continuously placing the test piece in the thermostat for low-temperature storage after water spraying is finished, observing and shooting the ice condensation condition of the surface of the test piece, and shooting by adopting an infrared thermal imaging camera during shooting to obtain an infrared image of the ice condensation on the surface of the test piece;
s3: according to the temperature of the ice-freezing infrared image, carrying out segmentation treatment on the ice-freezing infrared image;
s4: and calculating the area ratio of the ice melting part on the surface of the test piece according to the segmentation processing result, and taking the area ratio as an index for evaluating the pavement anti-freezing effect of the test piece.
Preferably, in step S1, the temperature simulating the winter low-temperature condition is-10 to 0 ℃.
Preferably, the time for the heat-retaining treatment in step S1 and the time for the low-temperature storage in step S2 are both 12 to 24 hours.
Preferably, in step S2, when the test piece is subjected to water spraying treatment, the water spraying treatment is performed using cold water at 1 to 5 ℃.
Preferably, in step S3, Matlab software is used to perform segmentation processing on the ice-freezing infrared map according to RGB or HSV components of the ice-freezing infrared map.
Preferably, in step S4, Matlab software is used to calculate the total area of the ice-melting infrared image and the local area of the ice-melting part, and the area ratio is obtained by calculating the percentage of the local area to the total area.
Preferably, the higher the area ratio, the better the anti-icing effect of the pavement at the time.
The invention has the beneficial effects that:
the method adopts a water spraying icing test and an ice freezing observation test to quantitatively evaluate and analyze the ice melting effect of the salt-storage asphalt mixture, and calculates the exposed area of the road surface after ice melting in the image and the percentage of the exposed area in the whole image area by segmenting the ice-condensation infrared image on the surface of the salt-storage asphalt concrete test piece, thereby realizing the effective detection of the anti-ice energy capacity of the salt-storage asphalt concrete road surface.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic diagram illustrating infrared results of surface ice condensation at an initial time of a test piece according to an embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating a segmentation processing result of an ice melting region of an infrared image of ice condensation on the surface of the test piece shown in FIG. 1;
FIG. 3 is a schematic diagram of the surface ice-freezing infrared results of the test piece 6h stored at low temperature according to one embodiment of the present invention;
FIG. 4 is a schematic diagram illustrating a segmentation processing result of an ice melting region of an infrared image of ice condensation on the surface of the test piece shown in FIG. 3;
FIG. 5 is a schematic diagram of the surface ice-freezing infrared results of a 12h low-temperature storage test piece according to an embodiment of the invention;
FIG. 6 is a schematic diagram of the ice melting region segmentation processing result of the infrared image of the ice freezing on the surface of the test piece shown in FIG. 5.
Detailed Description
The invention is further illustrated with reference to the following figures and examples. It should be noted that, in the present application, the embodiments and the technical features of the embodiments may be combined with each other without conflict. It is noted that, unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The use of the terms "comprising" or "including" and the like in the present disclosure is intended to mean that the elements or items listed before the term cover the elements or items listed after the term and their equivalents, but not to exclude other elements or items.
The invention provides a quantitative evaluation method for the anti-freezing performance of a salt-storage asphalt concrete pavement, which comprises the following steps:
s1: preparing a salt-storage asphalt concrete pavement test piece, and placing the test piece in a thermostat simulating a low-temperature condition in winter for heat preservation treatment.
In a specific embodiment, when the salt-storage asphalt concrete pavement test piece is prepared, a rutting plate test piece is manufactured according to a rule forming standard, and mineral powder in a conventional asphalt concrete formula is completely replaced by a salt-storage material to obtain the salt-storage asphalt concrete formula. It should be noted that the formulation of the salt-storage asphalt concrete can be configured in a one-to-one correspondence manner according to the formulation of the salt-storage asphalt concrete pavement in practical application.
In a specific embodiment, the temperature of the simulated winter low-temperature condition is-10 to 0 ℃, and it should be noted that the simulated winter low-temperature condition is set according to the winter temperature of the application area of the salt-storage asphalt concrete pavement, and the simulated winter low-temperature condition is different for different target areas.
S2: and carrying out water spraying treatment on the test piece, continuously placing the test piece in the thermostat for low-temperature storage after water spraying is finished, observing and shooting the ice condensation condition on the surface of the test piece, and shooting by adopting an infrared thermal imaging camera during shooting to obtain an infrared image of the ice condensation on the surface of the test piece.
In a specific embodiment, when the test piece is subjected to water spraying treatment, cold water with the temperature of 1-5 ℃ is adopted for water spraying treatment. It should be noted that the time for simulating freezing in the experiment can be saved by adopting cold water with a lower temperature for water spraying treatment, and the invention can also adopt normal temperature water for water spraying treatment, so that the time required by freezing is longer.
In a specific embodiment, when the test piece is subjected to water spraying treatment, water spraying parameters, such as precipitation amount, precipitation speed, precipitation temperature, precipitation test piece and the like, can also be determined according to the precipitation environment of the practical application area of the salt-storage asphalt concrete pavement.
In a specific embodiment, the time for performing the heat-preserving process in the step S1 and the time for performing the low-temperature preservation in the step S2 are both 12-24 h. It should be noted that the time is only the time preferred by the comprehensive cost of the present invention, and the present invention may also be tested with other storage time lengths.
S3: and carrying out segmentation treatment on the ice-freezing infrared image according to the temperature of the ice-freezing infrared image.
In a specific embodiment, Matlab software is used for segmenting the ice-freezing infrared image according to RGB or HSV components of the ice-freezing infrared image.
S4: and calculating the area ratio of the ice melting part on the surface of the test piece according to the segmentation processing result, and taking the area ratio as an index for evaluating the pavement anti-freezing effect of the test piece.
In a specific embodiment, Matlab software is used for calculating the whole area of the ice-freezing infrared image and the local area of the ice-melting part, the area ratio is obtained by calculating the percentage of the local area to the whole area, and the higher the area ratio is, the better the anti-icing effect of the pavement at the time is.
When the image area is calculated by using Matlab software, a function of the image area is calculated first, and then the area is calculated according to the function.
In a specific embodiment, the method of the present invention is used to quantitatively evaluate the anti-freezing performance of the saline-storage asphalt concrete pavement in a certain area, and the infrared result at the initial freezing time after the water spraying treatment in step S2 is shown in fig. 1, and the result of the segmentation treatment is shown in fig. 2; the result of the test piece surface ice-freezing infrared image after heat preservation for 6 hours is shown in figure 3, and the result of the segmentation treatment is shown in figure 4; the result of the test piece surface ice-freezing infrared image after heat preservation for 12 hours is shown in fig. 5, and the result of the segmentation treatment is shown in fig. 6; the area ratio result of the ice melting area to the whole ice melting infrared image on the surface of the test piece at each moment is obtained by Matlab calculation and is shown in Table 1:
TABLE 1 Ice melting zone area ratio results
| Time of day | Ice melting area (number of pixels) | Area to area ratio |
| Initial time | 203072 | 84.4192％ |
| Keeping the temperature for 6 hours | 122559 | 53.9727％ |
| Keeping the temperature for 12h | 100860 | 46.1334％ |
As is clear from Table 1, the anti-icing effect of the saline-storage asphalt concrete pavement of the present example was quantitatively evaluated at each time.
In conclusion, the method can quantitatively evaluate the anti-freezing performance of the salt storage asphalt concrete pavement, and has obvious progress compared with the prior art.
Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (7)
1. A method for quantitatively evaluating the anti-freezing performance of a salt-storage asphalt concrete pavement is characterized by comprising the following steps of:
s1: preparing a salt-storage asphalt concrete pavement test piece, and placing the test piece in a thermostat simulating a low-temperature condition in winter for heat preservation treatment;
s2: performing water spraying treatment on the test piece, continuously placing the test piece in the thermostat for low-temperature storage after water spraying is finished, observing and shooting the ice condensation condition of the surface of the test piece, and shooting by adopting an infrared thermal imaging camera during shooting to obtain an infrared image of the ice condensation on the surface of the test piece;
s3: according to the temperature of the ice-freezing infrared image, carrying out segmentation treatment on the ice-freezing infrared image;
s4: and calculating the area ratio of the ice melting part on the surface of the test piece according to the segmentation processing result, and taking the area ratio as an index for evaluating the pavement anti-freezing effect of the test piece.
2. The method for quantitatively evaluating the anti-icing performance of the saline asphalt concrete pavement according to claim 1, wherein in the step S1, the temperature for simulating the low-temperature condition in winter is-10 to 0 ℃.
3. The method for quantitatively evaluating the anti-icing performance of the saline-storage asphalt concrete pavement according to claim 2, wherein the time for performing the heat preservation treatment in the step S1 and the time for performing the low-temperature preservation in the step S2 are 12-24 hours.
4. The method for quantitatively evaluating the anti-freezing performance of the saline asphalt concrete pavement according to claim 1, wherein in the step S2, when the test piece is subjected to water spraying treatment, the test piece is subjected to water spraying treatment by using cold water at 1-5 ℃.
5. The method for quantitatively evaluating the anti-freezing performance of the saline asphalt concrete pavement according to claim 1, wherein in step S3, the ice-freezing infrared image is segmented according to RGB or HSV components of the ice-freezing infrared image by using Matlab software.
6. The method for quantitatively evaluating the anti-freezing performance of the saline asphalt concrete pavement according to claim 5, wherein in step S4, Matlab software is used to calculate the whole area of the ice-freezing infrared image and the local area of the ice-melting part, and the area ratio is obtained by calculating the percentage of the local area to the whole area.
7. The method for quantitatively evaluating the anti-icing performance of the saline asphalt concrete pavement according to any one of claims 1 to 6, wherein the higher the area ratio is, the better the anti-icing effect of the pavement is.
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Citations (8)
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|---|---|---|---|---|
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| CN209656534U (en) * | 2019-03-19 | 2019-11-19 | 长安大学 | A kind of device of the test anticoagulant ice performance of bituminous pavement of simulation dynamic load |
| CN111398335A (en) * | 2019-12-12 | 2020-07-10 | 长安大学 | Anti-freezing effect testing device with temperature sensor for infrared thermal imaging bituminous mixture |
| CN111504835A (en) * | 2020-05-19 | 2020-08-07 | 重庆交通大学 | Road surface low-temperature anti-icing simulation test device |
| CN211576568U (en) * | 2020-03-12 | 2020-09-25 | 吉林大学 | Anti ice and snow adhesion performance testing arrangement of vehicle chassis part |
| CN212622036U (en) * | 2020-05-19 | 2021-02-26 | 重庆交通大学 | Road surface low-temperature anti-icing simulation test device |
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2021
- 2021-11-05 CN CN202111306478.3A patent/CN114018969A/en active Pending
Patent Citations (8)
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|---|---|---|---|---|
| CN102313510A (en) * | 2010-07-02 | 2012-01-11 | 中国商用飞机有限责任公司 | Image icing detector |
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Application publication date: 20220208 |