A method and system for determining the timing of preventive maintenance of road surface deep diseases

Abstract

The application provides a method and system for determining the preventive maintenance opportunity of road surface deep disease, which comprises the following steps: scanning the current road section by an infrared sensor to obtain a road thermal imaging map, extracting an effective road thermal imaging map corresponding to an effective road section from the road thermal imaging map, when the effective road thermal imaging map has a low-temperature region, obtaining a low-temperature continuous region area according to all the low-temperature regions in the effective road thermal imaging map, when the low-temperature continuous region area is greater than a preset area threshold, regarding the road area corresponding to the low-temperature continuous region area as a target maintenance area, when the internal damage rate of the road surface is greater than a preset damage rate threshold, determining that the target maintenance area is a disease area, and sending a preventive maintenance reminder information to the target object. The application can simply and quickly locate and explore the deep hidden disease of the road surface, does not need complicated data analysis, and provides a determination method for the opportunity of taking preventive maintenance measures, which is beneficial to rapid maintenance decision.

Description

Technical Field

[0001] This invention relates to the field of pavement inspection technology, and in particular to a method and system for determining the timing of preventive maintenance for deep pavement defects. Background Technology

[0002] Most asphalt pavements in my country use inorganic binder-stabilized base courses (semi-rigid base courses) as their base structure. Semi-rigid base courses have advantages such as high load-bearing capacity and low cost; however, due to various reasons, they are prone to early damage, affecting the overall performance and lifespan of the asphalt pavement. Because semi-rigid base courses are hidden beneath the pavement, they are considered latent defects and are difficult to detect in a timely manner.

[0003] Currently, the treatment of hidden pavement defects generally involves waiting until the defects manifest on the road surface before proceeding. This approach is difficult, costly, time-consuming, pollutes the environment, and significantly impacts traffic. Trenchless treatment is generally ineffective in eradicating the problem, and the defects are prone to recurrence. Treating deep-seated hidden defects in their early stages, before they become unmanageable, would effectively reduce treatment costs and extend the pavement's service life.

[0004] Ground-penetrating radar (GPR) is the most commonly used non-destructive testing method for detecting deep defects in asphalt pavements. GPR is fast and can accurately detect the internal condition of the pavement. However, GPR detection has its limitations. Given the high cost of three-dimensional GPR, the commonly used GPR measurement range is two-dimensional single-line, which means it can only measure deep defects along one line. Deep defects are often localized, and single-line measurement is prone to errors and omissions. Setting up more measurement lines will increase the workload of testing, especially since radar images require manual interpretation and analysis. The processing of massive amounts of image information will greatly reduce efficiency and increase testing errors.

[0005] In view of this, it is necessary to propose a method and system for determining the timing of preventive maintenance for deep pavement defects in order to solve or at least alleviate the above-mentioned defects. Summary of the Invention

[0006] The main objective of this invention is to provide a method and system for determining the timing of preventive maintenance for deep pavement defects, in order to solve the problems of large testing workload and low testing efficiency in the existing technology of using two-dimensional single-line ground-penetrating radar to measure deep pavement defects.

[0007] To achieve the above objectives, the present invention provides a method for determining the timing of preventive maintenance for deep pavement defects, comprising the following steps:

[0008] S1, obtain the road surface thermal imaging map of the current road segment, extract the effective road surface thermal imaging map corresponding to the effective road segment from the road surface thermal imaging map, and determine whether there is a low temperature area in the effective road surface thermal imaging map.

[0009] S2, when there is a low-temperature region in the effective road surface thermal imaging map, the area of ​​the low-temperature continuous region is obtained based on all the low-temperature regions in the effective road surface thermal imaging map, and it is determined whether the area of ​​the low-temperature continuous region is greater than a preset area threshold.

[0010] S3, when the area of ​​the low-temperature continuous region is greater than the preset area threshold, the road surface area corresponding to the area of ​​the low-temperature continuous region is taken as the target maintenance area.

[0011] S4, obtain the internal damage rate of the road surface in the target maintenance area, and determine whether the internal damage rate of the road surface is greater than the preset damage rate threshold;

[0012] S5, when the internal damage rate of the road surface is greater than the preset damage rate threshold, the target maintenance area is determined to be a diseased area, and a preventive maintenance reminder message is sent to the target object.

[0013] Preferably, the "low-temperature region" in step S1 is obtained through the following steps:

[0014] S11, the effective road surface thermal imaging map is divided into multiple grid units according to a preset size grid;

[0015] S12, determine the average temperature of each grid cell;

[0016] S13, determine whether the average temperature of the grid is less than a preset temperature threshold, and determine whether the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value;

[0017] S14, when both of the following conditions are met simultaneously: the average temperature of the grid is less than a preset temperature threshold, and the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value, the grid cell is determined to be the low-temperature region.

[0018] Preferably, the "effective road segment" in step S1 is obtained through the following steps:

[0019] S101, Obtain the road surface condition information of the current road segment, and determine whether the road surface condition information meets the preset detection conditions;

[0020] S102, when the road condition information meets the preset detection conditions, the effective road thermal imaging map is divided into segments along the extension direction of the current road segment according to the preset length to obtain sub-segment road thermal imaging maps.

[0021] S103, perform temperature traversal analysis on the sub-segment road surface thermal imaging map along the extension direction of the current road segment, and determine the normal temperature and temperature fluctuation value in the sub-segment road surface thermal imaging map.

[0022] S104, determine whether the temperature fluctuation value is less than a preset temperature fluctuation threshold;

[0023] S105, when the temperature fluctuation value is less than the preset temperature fluctuation threshold, the road segment corresponding to the sub-segment road surface thermal imaging map is taken as the effective road segment;

[0024] S106, when the temperature fluctuation value is greater than or equal to the preset temperature fluctuation threshold, the sub-segment road surface thermal imaging map is divided into segments by reducing the preset length by a preset step size and using the adjusted preset length to obtain a secondary road surface thermal imaging map, and the secondary thermal imaging map is used as the sub-segment road surface thermal imaging map.

[0025] S107, repeat steps S103 to S106 until the temperature fluctuation value is less than the preset temperature fluctuation threshold, and take the road segment corresponding to the sub-segment road surface thermal imaging map as the effective road segment.

[0026] Preferably, step S104 is followed by the step:

[0027] S108, determine the average normal temperature in the thermal imaging map of the sub-segment road surface, and use the average normal temperature as the preset temperature threshold.

[0028] Preferably, the "area of ​​the low-temperature continuous region" in step S2 is obtained through the following steps:

[0029] S21, when the grid cell is a low temperature region, all grid cells that meet the condition of being a low temperature region and having a minimum distance between grid cells that is less than a first preset distance threshold are taken as the first continuous region; among them, grid cells with an area of ​​less than half a cell are counted as 0 cells, and grid cells with an area of ​​more than half a cell are counted as 1 cell.

[0030] S22, determine all first continuous regions that satisfy the condition that the minimum distance between two adjacent first continuous regions is less than a second preset distance threshold, and take the area of ​​all first continuous regions as the low-temperature continuous area; wherein, the second preset distance threshold is greater than the first preset distance threshold.

[0031] Preferably, step S4, "obtaining the internal pavement damage rate of the target maintenance area," specifically includes the following steps:

[0032] S41, Obtain the center point of the target maintenance area and establish two radar detection lines that intersect perpendicularly at the center point;

[0033] S42, according to the formula DR=(S r / S0)*100%, determine the internal pavement damage rate of the target maintenance area; where Sr S0 represents the cross-sectional area of ​​the radar spectrum corresponding to the radar detection line where damage exists, and S0 represents the total test cross-sectional area of ​​the radar spectrum corresponding to the radar detection line.

[0034] Preferably, step S13 is followed by the step:

[0035] S15, if neither of the following conditions is met: the average temperature of the grid is less than a preset temperature threshold, or the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value, the grid cell is determined to be a non-low temperature region.

[0036] Preferably, when the damage rate inside the road surface is less than or equal to a preset threshold, the target maintenance area is determined to be a non-disease area, and the process returns to step S1.

[0037] The present invention also provides a system for determining the timing of preventive maintenance for deep pavement defects, comprising an infrared temperature sensor, a radar detector, a pavement condition sensor, and a control system. The infrared temperature sensor, the radar detector, and the pavement condition sensor are all connected to the control system. The control system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method for determining the timing of preventive maintenance for deep pavement defects as described in any of the above claims.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] This invention provides a method and system for determining the timing of preventative maintenance for deep pavement defects. By acquiring a pavement thermal imaging map of the current road segment, the system extracts the effective pavement thermal imaging map corresponding to the effective road segment. When low-temperature areas are present in the effective pavement thermal imaging map, the area of ​​the continuous low-temperature area is calculated based on all low-temperature areas in the effective pavement thermal imaging map. If the area of ​​the continuous low-temperature area is greater than a preset area threshold, the pavement area corresponding to this area is designated as the target maintenance area. If the internal pavement damage rate is greater than a preset damage rate threshold, the target maintenance area is determined to be a defect area, and a preventative maintenance reminder is sent to the target area. This application enables simple and rapid location and detection of deep, latent pavement defects without cumbersome data analysis and provides a method for determining the timing of preventative maintenance measures, facilitating rapid maintenance decision-making. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of a process in one embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the area statistics of a low-temperature continuous region in one embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the radar detection line arrangement in a low-temperature continuous area according to one embodiment of the present invention.

[0044] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0045] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0047] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0048] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0049] Please see the appendix Figure 1-3 This invention provides a method for determining the timing of preventive maintenance for deep pavement defects, comprising the following steps:

[0050] S1, acquire the road surface thermal imaging map of the current road segment, extract the effective road surface thermal imaging map corresponding to the effective road segment from the road surface thermal imaging map, and determine whether there is a low temperature region in the effective road surface thermal imaging map; it is worth noting that this application extracts the effective road surface thermal imaging map corresponding to the effective road segment from the road surface thermal imaging map of the current road segment, and determines whether there is a low temperature region in the effective road surface thermal imaging map, that is, it first determines whether there is a low temperature region in the effective road surface thermal imaging map by temperature detection, that is, there may be a low temperature region, or there may be no low temperature region. In addition, research has found that deep road surface defects are generally caused by water damage. During the operation of asphalt pavement, due to the unavoidable voids in the asphalt pavement, water seeps into the pavement interior and causes internal damage to the pavement under the action of vehicle dynamic load. Therefore, areas with hidden defects inside the road surface generally have a high water permeability. In sunny weather, the temperature of areas with high water permeability is relatively low compared to the surrounding road surface. In this case, the water seepage of the road surface can be quickly detected by testing the road surface temperature with an infrared sensor, and the area with possible hidden defects can be located. Then, other non-destructive detection methods can be used to further analyze the internal hidden defects.

[0051] S2, when there are low-temperature areas in the effective road surface thermal imaging map, the area of ​​the continuous low-temperature area is obtained based on all low-temperature areas in the effective road surface thermal imaging map, and it is determined whether the area of ​​the continuous low-temperature area is greater than a preset area threshold. To fully meet actual engineering needs and avoid situations where only small (negligible) low-temperature areas are observed or where they are ignored due to discontinuity, this application detects disease zones / groups by obtaining the area of ​​the continuous low-temperature area based on all low-temperature areas in the effective road surface thermal imaging map when low-temperature areas are present, and then determining whether the area of ​​the continuous low-temperature area is greater than a preset area threshold. In a specific example, the preset area threshold is 2m². 2 That is, the area of ​​the continuous low-temperature region is greater than 2m². 2 When the area is relatively large, the corresponding road surface area can be used as the target maintenance area.

[0052] S3, when the area of ​​the low-temperature continuous region is greater than the preset area threshold, the road surface area corresponding to the low-temperature continuous region area is taken as the target maintenance area; it should be noted that the target maintenance area may be the area of ​​the diseased area that needs maintenance, or it may not be, so further analysis and judgment are required.

[0053] S4, obtain the internal pavement damage rate of the target maintenance area, and determine whether the internal pavement damage rate is greater than a preset damage rate threshold; In order to further improve the accuracy of the judgment of the disease area, this application obtains the internal pavement damage rate of the target maintenance area and determines whether the internal pavement damage rate is greater than a preset damage rate threshold. The internal pavement damage rate refers to the internal damage condition of the pavement, which usually refers to the presence of voids, looseness, interlayer discontinuity, and water content in the internal structure below the asphalt surface layer. These damage conditions can be analyzed by radar images.

[0054] S5, when the internal damage rate of the road surface exceeds the preset damage rate threshold, the target maintenance area is determined to be a defect area, and a preventive maintenance reminder message is sent to the target object. In a specific example, when the preset damage rate threshold is set to 30%, that is, when the internal damage rate of the road surface exceeds 30%, preventive maintenance is required, and a preventive maintenance reminder message can be sent to the target object. The target object can be a backend terminal or a staff member's handheld terminal; in another embodiment, the staff member can also proactively perform preventive maintenance on the defect area when the target maintenance area is determined to be a defect area.

[0055] This application enables a simple and quick way to locate and investigate deep-seated hidden road surface defects without the need for cumbersome data analysis. It also provides a method for determining the timing of preventative maintenance measures, which is beneficial for rapid maintenance decision-making.

[0056] In a preferred embodiment of the present invention, the "low-temperature region" in step S1 is specifically obtained through the following steps:

[0057] S11, the effective road surface thermal imaging map is divided into multiple grid units according to a preset size grid. It is worth noting that in order to quantify the temperature distribution in the effective road surface thermal imaging map, this embodiment divides the effective road surface thermal imaging map into multiple grid units according to a preset size grid. The specific size of the grid can be determined by those skilled in the art based on actual conditions. For example, the grid unit is a 20cm*20cm square grid.

[0058] S12, determine the average temperature of each grid cell; for example, several uniformly distributed temperature points within the grid cell can be selected, and the arithmetic mean of these temperature points can be calculated as the average temperature of the grid cell.

[0059] S13, determine whether the average temperature of the grid is less than a preset temperature threshold, and determine whether the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value;

[0060] S14, when both of the following conditions are met simultaneously: the average grid temperature is less than a preset temperature threshold, and the temperature difference rate between the average grid temperature and the preset temperature threshold is greater than a preset value, the grid cell is determined to be the low-temperature region. It should be noted that both the average grid temperature being less than the preset temperature threshold and the temperature difference rate between the average grid temperature and the preset temperature threshold being greater than the preset value will affect the selection of the low-temperature region. That is, grid cells with relatively low temperatures and large temperature variations are selected as low-temperature regions. Such low-temperature regions are highly likely to be diseased areas, thereby improving the accuracy of diseased area detection.

[0061] In a preferred embodiment of the present invention, the "effective road segment" in step S1 is specifically obtained through the following steps:

[0062] S101, Obtain the road surface condition information of the current road section and determine whether the road surface condition information meets the preset detection conditions; those skilled in the art will understand that research has found that deep road surface defects are generally caused by water damage. During the operation of asphalt pavement, due to the unavoidable voids in the asphalt pavement, water seeps into the pavement interior and causes internal damage under the dynamic load of vehicles. Therefore, areas with hidden defects inside the pavement generally have a high surface permeability. In sunny weather, areas with high pavement permeability are relatively cooler than the surrounding pavement. At this time, the pavement temperature can be tested by infrared sensors to quickly detect pavement water seepage, locate areas that may have hidden defects, and then further analyze the internal hidden defects using other non-destructive detection methods.

[0063] In a preferred embodiment, road surface condition information can be obtained through a road surface condition information sensor, such as detecting the humidity of the current road segment through a road surface humidity sensor, and then determining whether the current road segment meets the preset detection conditions. Alternatively, it can be determined by manual observation, such as when there is no obvious water accumulation on the road surface or it is not particularly dry. It can also be determined based on experience, such as within 3 days after rain, preferably after 1 day of sunshine, to determine that the road surface condition at this time meets the preset detection conditions.

[0064] S102, when the road condition information meets the preset detection conditions, the effective road thermal imaging map is divided into segments along the extension direction of the current road segment according to a preset length to obtain sub-segment road thermal imaging maps. It should be noted that due to different road locations and orientations, the normal road surface temperature range may fluctuate greatly. Therefore, segmented analysis is performed when analyzing the map. In this embodiment, the effective road thermal imaging map is divided into segments along the extension direction of the current road segment according to a preset length to obtain sub-segment road thermal imaging maps, that is, the analysis is performed separately according to multiple sub-segments.

[0065] S103, perform temperature traversal analysis on the sub-segment road surface thermal imaging map along the extension direction of the current road segment, and determine the normal temperature and temperature fluctuation value in the sub-segment road surface thermal imaging map.

[0066] S104, determine whether the temperature fluctuation value is less than a preset temperature fluctuation threshold;

[0067] S105, when the temperature fluctuation value is less than the preset temperature fluctuation threshold, the road segment corresponding to the sub-segment road surface thermal imaging map is taken as the effective road segment;

[0068] S106, when the temperature fluctuation value is greater than or equal to the preset temperature fluctuation threshold, the sub-segment road surface thermal imaging map is divided into segments by reducing the preset length by a preset step size and using the adjusted preset length to obtain a secondary road surface thermal imaging map, and the secondary thermal imaging map is used as the sub-segment road surface thermal imaging map.

[0069] S107, repeat steps S103 to S106 until the temperature fluctuation value is less than the preset temperature fluctuation threshold, and take the road segment corresponding to the sub-segment road surface thermal imaging map as the effective road segment.

[0070] Understandably, in order to identify road segments with smaller normal temperature fluctuations as effective road segments, temperature traversal analysis is performed on the sub-segment road surface thermal imaging map along the extension direction of the current road segment to obtain the temperature set of all sub-segment road surface thermal imaging maps and determine the normal temperature in the sub-segment road surface thermal imaging map. The normal temperature is the temperature of most areas of the road surface. When the temperature fluctuation value is less than the preset temperature fluctuation threshold, the road segment corresponding to the sub-segment road surface thermal imaging map is taken as the effective road segment, thereby separating and analyzing road segments with significant fluctuations. If the temperature fluctuation value is greater than or equal to the preset temperature fluctuation threshold, the sub-segment road surface thermal imaging map is divided into sub-segment road surface thermal imaging maps by reducing the preset length by a preset step size, and the adjusted preset length is used as the sub-segment road surface thermal imaging map. The preset step size can be set to reduce by 10m each time. Steps S103 to S106 are repeated cyclically until the temperature fluctuation value is less than the preset temperature fluctuation threshold. The road segment corresponding to the sub-segment road surface thermal imaging map is then designated as the valid road segment. This process selects road segments with temperature fluctuation ranges that meet expectations as valid road segments, improving detection accuracy.

[0071] In a preferred embodiment, the operator can analyze and provide the normal temperature and temperature fluctuation threshold of a specific sub-section based on engineering experience, and adjust the sub-section length according to the given normal temperature and temperature fluctuation threshold, and select the section with the expected temperature fluctuation range as the effective section.

[0072] In a specific example, the preset temperature fluctuation threshold is set to 2℃, meaning that the road segment whose temperature fluctuation value in the sub-segment road surface thermal imaging map is less than 2℃ can be considered a valid road segment.

[0073] As a preferred implementation, step S104 is followed by step S108, which involves determining the average normal temperature in the sub-segment road surface thermal imaging map and using this average normal temperature as the preset temperature threshold. Because the normal road surface temperature may fluctuate significantly depending on its location and orientation, using the average normal temperature in the sub-segment road surface thermal imaging map as the preset temperature threshold can more accurately reflect the temperature of the corresponding road segment in the sub-segment road surface thermal imaging map. Using this temperature as a reference can improve the accuracy of the results.

[0074] As a preferred implementation, the "area of ​​low-temperature continuous region" in step S2 is obtained through the following steps: S21, when the grid cell is a low-temperature region, all grid cells that meet the condition that the grid cell is a low-temperature region and the minimum distance between grid cells is less than a first preset distance threshold are taken as the first continuous region; wherein, grid cells with an area of ​​less than half a cell are counted as 0 cells, and grid cells with an area of ​​more than half a cell are counted as 1 cell.

[0075] S22, determine all first continuous regions that satisfy the condition that the minimum distance between two adjacent first continuous regions is less than a second preset distance threshold, and use the area of ​​all first continuous regions as the low-temperature continuous area; wherein, the second preset distance threshold is greater than the first preset distance threshold. It should be noted that the "low-temperature continuous area" in this embodiment is not entirely composed of continuous low-temperature regions. To improve convenience, this embodiment calculates the number and area of ​​continuous low-temperature region cells, and further considers closely spaced first continuous regions as continuous regions, thus quickly obtaining a low-temperature continuous area that better meets the actual needs of the project, improving the efficiency of operation and maintenance. Preferably, the first preset distance threshold is set to 10cm. The second preset distance threshold is set to 1m. In other embodiments, those skilled in the art can set the preset distance threshold to other values, depending on actual needs.

[0076] As a preferred embodiment, step S4, "obtaining the pavement internal damage rate of the target maintenance area," specifically includes the following steps: S41, obtaining the center point of the target maintenance area, and establishing two radar detection lines perpendicularly intersecting the center point. Please refer to the appendix. Figure 3 Because this application divides the effective road surface thermal imaging map into a grid, the center point of the target maintenance area can be easily obtained. To accurately detect the internal pavement damage rate of the target maintenance area, two radar detection lines perpendicularly intersecting the center point are established, for example... Figure 3 The system includes both horizontal and vertical radar detection lines, with these two lines intersecting at the center point. This method can accurately reflect the internal damage status of the target maintenance area. In other embodiments, the number and distribution of radar detection lines can be appropriately increased or decreased according to the shape of the target maintenance area. For example, if the target maintenance area is long and narrow, more radar detection lines can be added as needed.

[0077] S42, according to the formula DR=(S r / S0)*100%, determine the internal pavement damage rate of the target maintenance area; where S r S0 represents the cross-sectional area of ​​the radar image corresponding to the radar detection line where damage exists, and S0 represents the total test cross-sectional area on the radar image corresponding to the radar detection line. It is worth noting for those skilled in the art that ground-penetrating radar (GPR) is the most commonly used non-destructive testing method for detecting deep defects in asphalt pavements. GPR is fast and can accurately detect the internal condition of the pavement. However, GPR detection has its limitations. Given the high cost of three-dimensional GPR, the commonly used GPR measurement range is currently two-dimensional single-line, meaning it can only measure deep defects along one line. Deep defects are often localized, and single-line measurements are prone to errors and omissions. Deploying multiple measurement lines increases the testing workload, especially since radar images require manual interpretation and analysis. Processing massive amounts of image information greatly reduces efficiency and increases testing errors. This embodiment of the application deploys two radar detection lines, using the formula DR = (S0 / S0)... r The formula DR ( / S0)*100% can calculate the ratio of the cross-sectional area with damage on two lines to the total cross-sectional area of ​​the test. This ratio DR can accurately reflect the internal damage rate of the road surface.

[0078] As an optional implementation, step S13 is followed by step S15, where the grid cell is determined to be a non-low-temperature region if neither of the following conditions is met: the average grid temperature is less than a preset temperature threshold, or the temperature difference rate between the average grid temperature and the preset temperature threshold is greater than a preset value. It should be noted that if the average grid temperature is greater than or equal to the preset temperature threshold, it indicates that the grid cell is not a low-temperature region and preventative maintenance is not required; if the temperature difference rate between the preset temperature thresholds is less than or equal to the preset value, it indicates that the temperature change of the grid cell is very small, and preventative maintenance is also not required. Alternatively, if neither condition is met, preventative maintenance is also not required.

[0079] As an optional implementation, when the internal pavement damage rate is less than or equal to a preset threshold, the target maintenance area is determined to be a non-disease area, and the process returns to step S1. It is understood that when the internal pavement damage rate is less than or equal to the preset threshold, the target maintenance area is not a disease area, or the degree of disease in the area is relatively mild, and maintenance of the target maintenance area is not required.

[0080] This invention also provides a system for determining the timing of preventive maintenance for deep pavement defects, comprising an infrared temperature sensor, a radar detector, a pavement condition sensor, and a control system. The infrared temperature sensor scans to obtain a thermal image of the entire pavement; preferably, a vehicle-mounted infrared permeability detector for highway asphalt pavement is used, with a detection width of one lane. The radar detector detects the internal condition of asphalt pavement in low-temperature areas by using ground-penetrating radar to detect internal pavement damage in these areas. The pavement condition sensor, such as an embedded pavement condition sensor, acquires pavement conditions such as humidity and determines whether the current road section meets the detection conditions based on these conditions. The infrared temperature sensor, the radar detector, and the pavement condition sensor are all connected to the control system. The control system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method for determining the timing of preventive maintenance for deep pavement defects as described above.

[0081] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for determining the timing of preventative maintenance for deep pavement defects, characterized in that, Including the following steps: S1, scan the road surface thermal imaging map of the test road section, extract the effective road surface thermal imaging map corresponding to the effective road section from the road surface thermal imaging map, and determine whether there is a low temperature area in the effective road surface thermal imaging map. S2, when there is a low-temperature region in the effective road surface thermal imaging map, the area of ​​the low-temperature continuous region is obtained based on all the low-temperature regions in the effective road surface thermal imaging map, and it is determined whether the area of ​​the low-temperature continuous region is greater than a preset area threshold. S3, when the area of ​​the low-temperature continuous region is greater than the preset area threshold, the road surface area corresponding to the area of ​​the low-temperature continuous region is taken as the target maintenance area. S4, obtain the internal damage rate of the road surface in the target maintenance area, and determine whether the internal damage rate of the road surface is greater than the preset damage rate threshold; S5, when the internal damage rate of the road surface is greater than the preset damage rate threshold, the target maintenance area is determined to be a diseased area, and a preventive maintenance reminder message is sent to the target object; The "effective road segment" in step S1 is obtained through the following steps: S101, Obtain road surface condition information of the current road segment, and determine whether the road surface condition information meets the preset detection conditions; S102, when the road condition information meets the preset detection conditions, the effective road thermal imaging map is divided into segments along the extension direction of the current road segment according to the preset length to obtain sub-segment road thermal imaging maps. S103, perform temperature traversal analysis on the sub-segment road surface thermal imaging map along the extension direction of the current road segment, and determine the normal temperature and temperature fluctuation value in the sub-segment road surface thermal imaging map. S104, determine whether the temperature fluctuation value is less than a preset temperature fluctuation threshold; S105, when the temperature fluctuation value is less than the preset temperature fluctuation threshold, the road segment corresponding to the sub-segment road surface thermal imaging map is taken as the effective road segment; S106, when the temperature fluctuation value is greater than or equal to the preset temperature fluctuation threshold, the sub-segment road thermal imaging map is divided into segments by reducing the preset length by a preset step size and using the adjusted preset length to obtain a secondary road thermal imaging map, and the secondary road thermal imaging map is used as the sub-segment road thermal imaging map. S107, repeat steps S103~S106 until the temperature fluctuation value is less than the preset temperature fluctuation threshold, and take the road segment corresponding to the sub-segment road surface thermal imaging map as the effective road segment. Step S4, "obtaining the internal pavement damage rate of the target maintenance area," specifically includes the following steps: S41, Obtain the center point of the target maintenance area and establish two radar detection lines that intersect perpendicularly at the center point; S42, according to the formula DR=(S r / S0) 100%, determine the internal pavement damage rate of the target maintenance area; where S r S0 represents the cross-sectional area of ​​the radar spectrum corresponding to the radar detection line where damage exists, and S0 represents the total test cross-sectional area of ​​the radar spectrum corresponding to the radar detection line.

2. The method for determining the timing of preventive maintenance for deep pavement defects according to claim 1, characterized in that, The "low-temperature region" in step S1 is obtained through the following steps: S11, the effective road surface thermal imaging map is divided into multiple grid units according to a preset size grid; S12, determine the average temperature of each grid cell; S13, determine whether the average temperature of the grid is less than a preset temperature threshold, and determine whether the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value; S14, when both of the following conditions are met simultaneously: the average temperature of the grid is less than a preset temperature threshold, and the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value, the grid cell is determined to be the low-temperature region.

3. The method for determining the timing of preventive maintenance for deep pavement defects according to claim 1, characterized in that, The step S104 is followed by the following step: S108, determine the average normal temperature in the thermal imaging map of the sub-segment road surface, and use the average normal temperature as a preset temperature threshold.

4. The method for determining the timing of preventive maintenance for deep pavement defects according to claim 2, characterized in that, The "area of ​​the low-temperature continuous region" in step S2 is obtained through the following steps: S21, when the grid cell is a low temperature region, all grid cells that meet the condition of being a low temperature region and having a minimum distance between grid cells that is less than a first preset distance threshold are taken as the first continuous region; among them, grid cells with an area of ​​less than half a cell are counted as 0 cells, and grid cells with an area of ​​more than half a cell are counted as 1 cell. S22, determine all first continuous regions that satisfy the condition that the minimum distance between two adjacent first continuous regions is less than a second preset distance threshold, and take the area of ​​all first continuous regions as the low-temperature continuous area; wherein, the second preset distance threshold is greater than the first preset distance threshold.

5. The method for determining the timing of preventive maintenance for deep pavement defects according to claim 2, characterized in that, The step S13 is followed by the following step: S15, if neither of the following conditions is met: the average temperature of the grid is less than a preset temperature threshold, or the temperature difference rate between the average temperature of the grid and the preset temperature threshold is greater than a preset value, the grid cell is determined to be a non-low temperature region.

6. The method for determining the timing of preventive maintenance for deep pavement defects according to claim 1, characterized in that, When the internal damage rate of the road surface is less than or equal to a preset threshold, the target maintenance area is determined to be a non-disease area, and the process returns to step S1.

7. A system for determining the timing of preventative maintenance for deep pavement defects, characterized in that, The system includes an infrared temperature sensor, a radar detector, a road surface condition sensor, and a control system. The infrared temperature sensor, the radar detector, and the road surface condition sensor are all connected to the control system. The control system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method for determining the timing of preventive maintenance for deep pavement defects as described in any one of claims 1 to 6.

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