Cable protective layer sealing performance monitoring method and device

Abstract

The invention provides a cable protection layer sealing performance monitoring method and device, and belongs to the technical field of bridge health monitoring, and the method comprises the steps that the axial temperature distribution and the axial humidity distribution of a cable body are obtained, and the cable body comprises a cable strand and a protection layer wrapping the cable strand; determining a first position where the sealing performance of the protective layer is reduced based on the axial temperature distribution and a reference axial temperature distribution; determining a second position where the sealing performance of the protective layer is reduced based on the axial humidity distribution and a reference axial humidity distribution; and when the first position is the same as the second position, determining that the sealing performance of the protective layer is reduced. According to the invention, the sealing performance of the protection layer is monitored through two different physical quantities of temperature and humidity, the problems of high contingency and unreliability of a single temperature judgment result are avoided, and the accuracy and reliability of monitoring the sealing performance of the cable protection layer are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge health monitoring, and in particular to a method and device for monitoring the sealing performance of a cable protective layer. Background Art

[0002] The protective layer of bridge cables is one or more layers of material wrapped around the outside of the metal cable (strand), which mainly plays the role of protection, stability, heat insulation and chemical protection; however, due to construction and weather reasons, the sealing performance of the protective layer will decrease (damage) to varying degrees, and its structural state is the key to the health of the bridge cable structure.

[0003] The existing monitoring and maintenance technologies for protective layers mainly include: using climbing equipment manually or climbing robots and drones to conduct appearance inspections. Manual inspections on cables are dangerous and inefficient, while machine inspections are efficient but have low accuracy; sampling is performed on cable wrapping aging and cracking parts for tensile strength, fracture extension and other performance tests. This method can accurately detect the damage to the parts where the sealing performance has decreased; regular cable force tests are performed, mainly including the magnetic flux method that reflects stress changes by measuring changes in magnetic permeability, testing the cable vibration frequency through an acceleration sensor and converting it to obtain tension, and the millimeter wave radar non-contact test method, but there is still a problem of low accuracy. In order to solve the various deficiencies in the above traditional methods, CN119043520A proposes a method for monitoring the protective layer through a sensing optical cable. Specifically, it obtains the temperature distribution of the cable and monitors the sealing performance of the protective layer through changes in the temperature distribution. It has the following technical problems: the sealing performance is monitored through a single temperature distribution, and the monitoring results are unreliable and have low accuracy.

[0004] Therefore, there is an urgent need to provide a method and device for monitoring the sealing performance of the cable protective layer, which can improve the reliability and accuracy of the monitoring results by introducing additional physical quantities and temperature distribution to jointly monitor the sealing performance of the protective layer. Summary of the invention

[0005] In view of this, it is necessary to provide a method and device for monitoring the sealing performance of a cable protective layer, so as to solve the technical problem in the prior art that the sealing performance of the protective layer is monitored only by a single temperature distribution, resulting in low reliability and accuracy of the monitoring results.

[0006] In a first aspect, in order to solve the above technical problems, the present invention provides a method for monitoring the sealing performance of a cable protective layer, comprising: Acquire an axial temperature distribution and an axial humidity distribution of a cable body, wherein the cable body comprises strands and a protective layer wrapping the strands; determining a first position where the sealing performance of the protective layer decreases based on the axial temperature distribution and a reference axial temperature distribution; Determine a second position where the sealing performance of the protective layer deteriorates based on the axial humidity distribution and the reference axial humidity distribution; When the first position and the second position are the same, it is determined that the sealing performance of the protective layer deteriorates.

[0007] In a possible implementation, the determining the first position where the sealing performance of the protective layer deteriorates based on the axial temperature distribution and the reference axial temperature distribution includes: Determine the heat conduction direction of the cable body and the temperature judgment strategy corresponding to the heat conduction direction; Determine the first position based on the temperature judgment strategy.

[0008] In a possible implementation, the heat conduction direction includes the direction of conduction towards the inside of the cable body and the direction of conduction towards the outside of the cable body; When the heat conduction direction is the direction of conduction towards the inside of the cable body, the temperature judgment strategy is: the temperature value in the axial temperature distribution corresponding to the first position is less than the reference temperature value in the reference axial temperature distribution corresponding to the first position; When the heat conduction direction is the direction of conduction towards the outside of the cable body, the temperature judgment strategy is: the temperature value in the axial temperature distribution corresponding to the first position is greater than the reference temperature value in the reference axial temperature distribution corresponding to the first position.

[0009] In a possible implementation, the determining the first position based on the temperature judgment strategy includes: When the heat conduction direction is the direction of conduction towards the inside of the cable body, determine a first candidate area where the temperature value in the axial temperature distribution is less than the reference temperature value in the reference axial temperature distribution; determine whether the temperature difference between the temperature value and the reference temperature value in the first candidate area is greater than a preset difference; if it is greater, use the position of the minimum temperature value among the temperature values as the first position; When the heat conduction direction is the direction of conduction towards the outside of the cable body, determine a second candidate area where the temperature value in the axial temperature distribution is greater than the reference temperature value in the reference axial temperature distribution; determine whether the temperature difference between the temperature value and the reference temperature value in the second candidate area is greater than a preset difference; if it is greater, use the position of the maximum temperature value among the temperature values as the first position.

[0010] In a possible implementation, the determining the second position where the sealing performance of the protective layer deteriorates based on the axial humidity distribution and the reference axial humidity distribution includes: Determine the moisture diffusion direction of the cable body and the humidity judgment strategy corresponding to the moisture diffusion direction; Determine the second position based on the humidity judgment strategy.

[0011] In a possible implementation, the moisture diffusion direction includes diffusion into the cable body and diffusion out of the cable body; When the moisture diffusion direction is the conduction direction out of the cable body, the humidity judgment strategy is: the humidity value in the axial humidity distribution corresponding to the second position is greater than the reference humidity value in the reference axial humidity distribution corresponding to the second position; When the moisture diffusion direction is the conduction direction into the cable body, the humidity judgment strategy is: the humidity value in the axial humidity distribution corresponding to the second position is less than the reference temperature value in the reference axial humidity distribution corresponding to the second position.

[0012] In a possible implementation, the determining the second position based on the humidity judgment strategy includes: When the moisture diffusion direction is the conduction direction out of the cable body, determine the first target area where the humidity value in the axial humidity distribution is less than the reference humidity value in the reference axial humidity distribution; determine whether the humidity difference between the humidity value and the reference humidity value in the first target area is greater than a preset humidity; if it is greater, use the position of the maximum humidity value in the humidity values as the second position; When the moisture diffusion direction is the conduction direction into the cable body, determine the second target area where the humidity value in the axial humidity distribution is greater than the reference humidity value in the reference axial humidity distribution; determine whether the humidity difference between the humidity value and the reference humidity value in the second target area is greater than a preset humidity; if it is greater, use the position of the minimum humidity value in the humidity values as the second position.

[0013] In a possible implementation, the method further includes: Obtain the radial temperature distribution and the reference radial temperature distribution at the first position; Determine the temperature deformation area and the temperature deformation direction in the radial temperature distribution based on the reference radial temperature distribution; Determine the heat conduction direction of the cable body based on the radial temperature distribution, and determine whether the sealing performance of the temperature deformation area has decreased based on the heat conduction direction and the temperature deformation direction.

[0014] In a possible implementation, the method further includes: Obtain the radial humidity distribution and the reference radial humidity distribution at the first position; Determine the humidity deformation region and the humidity deformation direction in the radial humidity distribution based on the reference radial humidity distribution; Determine the moisture diffusion direction of the cable body based on the humidity temperature distribution, and determine whether the sealing performance of the humidity deformation region has decreased based on the moisture diffusion direction and the humidity deformation direction.

[0015] In a second aspect, the present invention also provides a monitoring device for the sealing performance of a cable protective layer, including: A temperature and humidity distribution acquisition unit for acquiring the axial temperature distribution and the axial humidity distribution of the cable body, where the cable body includes cable strands and a protective layer wrapping the cable strands; A sealing performance temperature monitoring unit for determining a first position where the sealing performance of the protective layer has decreased based on the axial temperature distribution and a reference axial temperature distribution; A sealing performance humidity monitoring unit for determining a second position where the sealing performance of the protective layer has decreased based on the axial humidity distribution and a reference axial humidity distribution; A sealing performance determination unit for determining that the sealing performance of the protective layer has decreased when the first position and the second position are the same.

[0016] The beneficial effects of the present invention are as follows: In the method for monitoring the sealing performance of the cable protective layer provided by the present invention, after determining the first position based on the axial temperature distribution, the second position is also determined based on the axial humidity distribution, that is, the sealing performance of the protective layer is monitored through two different physical quantities, temperature and humidity. Moreover, when the first position and the second position are the same, it is determined that the sealing performance of the protective layer has decreased, avoiding the technical problems of large contingency and unreliability in the single temperature judgment result. In other words, through the analysis of the temperature and humidity field distribution, the present invention realizes an accurate judgment on whether the sealing performance of the protective layer has decreased, that is, improves the accuracy and reliability of the monitoring of the sealing performance of the cable protective layer. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic flowchart of an embodiment of the method for monitoring the sealing performance of the cable protective layer provided by the present invention; Figure 2 It is a schematic flowchart of an embodiment of step S102 of the present invention; Figure 3A comparative diagram of an embodiment of the axial temperature distribution and the reference axial temperature distribution provided by the present invention; Figure 4 A schematic flowchart of an embodiment of step S103 of the present invention; Figure 5 A comparative diagram of an embodiment of the axial humidity distribution and the reference axial humidity distribution provided by the present invention; Figure 6 A schematic flowchart of an embodiment for judging whether the sealing performance deteriorates based on the radial temperature distribution provided by the present invention; Figure 7 A comparative schematic diagram of an embodiment of the radial temperature distribution and the reference radial temperature distribution provided by the present invention; Figure 8 A schematic flowchart of an embodiment for judging whether the sealing performance deteriorates based on the radial humidity distribution provided by the present invention; Figure 9 A comparative schematic diagram of an embodiment of the radial humidity distribution and the reference radial humidity distribution provided by the present invention; Figure 10 A schematic structural diagram of an embodiment of the cable protection layer sealing performance monitoring device provided by the present invention. Detailed implementation manners

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0020] It should be understood that the schematic drawings are not drawn to actual scale. The flowcharts used in the present invention illustrate the operations implemented according to some embodiments of the present invention. It should be understood that the operations in the flowchart may not be implemented in sequence, and steps without logical context relationships may be reversed or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart or remove one or more operations from the flowchart under the guidance of the content of the present invention. Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor systems and / or microcontroller systems.

[0021] Reference to "embodiment" in this text means that the specific features, structures, or characteristics described in connection with the embodiment may be included in at least one embodiment of the present invention. The phrase appears at various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0022] The present invention provides a method and device for monitoring the sealing performance of a cable protection layer, which will be described separately below.

[0023] Figure 1 FIG. is a schematic flowchart of an embodiment of the method for monitoring the sealing performance of the cable protection layer provided by the present invention. As Figure 1 shown, the method for monitoring the sealing performance of the cable protection layer includes: S101. Obtain the axial temperature distribution and axial humidity distribution of the cable core. The cable core includes cable strands and a protection layer that wraps the cable strands.

[0024] Among them, the axial temperature distribution is obtained based on the analysis and arrangement of the temperature data collected in real time by the temperature sensing optical cable embedded inside the cable core, and the axial humidity distribution is obtained based on the analysis and arrangement of the humidity data collected in real time by the humidity sensing optical cable embedded inside the cable core.

[0025] Among them, the protection layer is a functional structural layer used to protect the cable strands from external environmental erosion, physical damage, or functional interference.

[0026] S102. Determine the first position where the sealing performance of the protection layer deteriorates based on the axial temperature distribution and the reference axial temperature distribution.

[0027] Among them, the reference axial temperature distribution is the axial temperature distribution when the sealing performance of the protection layer of the cable core does not deteriorate.

[0028] The principle for determining the single position where the sealing performance of the protection layer deteriorates based on the axial temperature distribution and the reference axial temperature distribution is as follows: The cable strands are several parallel steel cables, which are metal materials, and the protection layer is a non-metal material. There is a significant difference in the heat transfer rate between the non-metal material and the metal material. In the initial stage of the completed bridge, the cable structure is stable, and the heat conduction process is also stable. The part of the cable structure most affected by external temperature changes is thermal radiation, that is, the changes in the position and intensity of sunlight within a day. At this time, the thermal radiation received by the entire cable structure is basically the same. The formula for the heat transfer efficiency is as follows:

[0029] In the formula, is the heat transfer efficiency per unit area, is the thermal conductivity of the material; is the temperature gradient. It can be seen from the formula that when the external temperature changes are the same, due to the different thermal conductivities of the protective layer and the cable strands, for example, the thermal conductivity of the protective layer is small, so the rate of heat transfer is slow and the heat transfer efficiency is low; the thermal conductivity of the cable strands is large, so the heat transfer rate and heat transfer efficiency are high, and heat can be transferred quickly. That is, a stable axial temperature distribution will appear inside the cable body. When the sealing performance of the protective layer decreases, the heat-conducting material at the decreased part becomes air, and its thermal conductivity is different from that of the protective layer, and the axial temperature distribution will change greatly. Therefore, through the axial temperature distribution, it can be determined whether the sealing performance of the protective layer has decreased and the first position where the sealing performance has decreased.

[0030] S103. Determine the second position where the sealing performance of the protective layer has decreased based on the axial humidity distribution and the reference axial humidity distribution.

[0031] Among them, the reference axial humidity distribution is the axial humidity distribution when the sealing performance of the protective layer of the cable body has not decreased.

[0032] The principle of determining the second position where the sealing performance of the protective layer has decreased based on the axial humidity distribution and the reference axial humidity distribution is as follows: The humidity gradient inside and outside the protective layer (i.e., the water vapor concentration difference or relative humidity difference) will directly affect the moisture diffusion rate. If the sealing performance of the cable protective layer decreases, the diffusion medium during the moisture diffusion process is air, and the flow rate of the diffused substance per unit area (i.e., the diffusion flux J) is proportional to the humidity gradient on both sides of the diffusion interface, that is:

[0033] In the formula, D is the diffusion coefficient, is the humidity gradient. It can be known from this that the greater the humidity gradient inside and outside, the faster the diffusion rate, and the diffusion rate of moisture is proportional to the concentration difference. When the sealing performance of the protective layer decreases (is damaged), the diffusion medium at the decreased part of the sealing performance becomes air, and its diffusion coefficient is different from that of the protective layer, and the axial humidity distribution will change greatly. Therefore, through the axial humidity distribution, it can be determined whether the sealing performance of the protective layer has decreased and the second position where the sealing performance has decreased.

[0034] S104. When the first position and the second position are the same, determine that the sealing performance of the protective layer has decreased.

[0035] It should be noted that the humidity distribution and the temperature are negatively correlated. For example, when the axial temperature distribution first rises and then falls, the axial humidity distribution first falls and then rises. This is because when the temperature rises, if the actual water vapor content remains unchanged, the increase in the saturated water vapor pressure will lead to a decrease in the relative humidity, thus forming a negative correlation between temperature and humidity.

[0036] It should also be noted that: in order to provide a monitoring margin for sealing performance monitoring and to avoid the influence of parameters such as data acquisition accuracy on position judgment, in some embodiments of the present invention, the first position and the second position being the same means that the position difference between the first position and the second position is not greater than a preset position difference.

[0037] It should be understood that the preset position difference can be set or adjusted according to actual application scenarios or empirical values.

[0038] Compared with the prior art, the cable protective layer sealing performance monitoring method provided by the embodiment of the present invention determines the second position based on the axial humidity distribution after determining the first position based on the axial temperature distribution, that is, the sealing performance of the protective layer is monitored by two different physical quantities, temperature and humidity, and only when the first position and the second position are the same, it is determined that the sealing performance of the protective layer has decreased, thus avoiding the technical problem that the single temperature judgment result is highly accidental and unreliable. In other words, the embodiment of the present invention achieves an accurate judgment on whether the sealing performance of the protective layer has decreased by analyzing the temperature and humidity field distribution, that is, the accuracy and reliability of the monitoring of the sealing performance of the cable protective layer are improved.

[0039] Since the direction of heat conduction is from a place with high temperature to a place with low temperature, during the day, when the temperature rises during the day, the temperature of the cable body is lower than the ambient temperature, and when the temperature drops at night, the temperature of the cable body is higher than the ambient temperature, that is, the heat sensing direction of the cable body is not constant. Considering this situation, in some embodiments of the present invention, such as Figure 2 As shown, step S102 includes: S201, determining the heat conduction direction of the cable body and the temperature judgment strategy corresponding to the heat conduction direction.

[0040] Specifically, the heat conduction direction includes the conduction direction toward the inside of the cable body and the conduction direction toward the outside of the cable body. Since different heat conduction directions will lead to different distribution gradients of axial temperature distribution, it is necessary to set a temperature judgment strategy based on the heat conduction direction.

[0041] S202: Determine a first position based on a temperature judgment strategy.

[0042] The embodiment of the present invention uses the heat conduction direction as a reference factor to determine the temperature judgment strategy, thereby further improving the monitoring accuracy of the first position.

[0043] In a specific embodiment of the present invention, when the heat conduction direction is the direction of conduction toward the inside of the cable body, the temperature judgment strategy is: the temperature value in the axial temperature distribution corresponding to the first position is less than the reference temperature value in the reference axial temperature distribution corresponding to the first position; When the heat conduction direction is the direction of conduction to the outside of the cable body, the temperature judgment strategy is: the temperature value in the axial temperature distribution corresponding to the first position is greater than the reference temperature value in the reference axial temperature distribution corresponding to the first position.

[0044] In summary, the thermal conductivity of air is smaller than that of the protective layer. Therefore, the heat transferred by air is smaller, resulting in a lag in the temperature change at the position where the sealing performance deteriorates. Furthermore, when the heat conduction direction is the direction of conduction to the inside of the cable body, the temperature value of the axial temperature distribution at the position where the sealing performance deteriorates is less than the reference temperature value of the reference axial temperature distribution. When the heat conduction direction is the direction of conduction to the outside of the cable body, the temperature value of the axial temperature distribution at the position where the sealing performance deteriorates is greater than the reference temperature value of the reference axial temperature distribution.

[0045] In a specific embodiment of the present invention, step S202 includes: When the heat conduction direction is the direction of conduction to the inside of the cable body, determine a first candidate area where the temperature value in the axial temperature distribution is less than the reference temperature value in the reference axial temperature distribution; judge whether the temperature difference between the temperature value and the reference temperature value in the first candidate area is greater than a preset difference; if it is greater, take the position where the minimum temperature value in the temperature value is located as the first position; When the heat conduction direction is the direction of conduction to the outside of the cable body, determine a second candidate area where the temperature value in the axial temperature distribution is greater than the reference temperature value in the reference axial temperature distribution; judge whether the temperature difference between the temperature value and the reference temperature value in the second candidate area is greater than a preset difference; if it is greater, take the position where the maximum temperature value in the temperature value is located as the first position.

[0046] In a specific embodiment of the present invention, taking the heat conduction direction being the direction of conduction to the inside of the cable body as an example, as Figure 3 shown, Figure 3 the abscissa in is the position of the cable body, the ordinate is the temperature, the black line is the reference axial temperature distribution, and the red line is the axial temperature distribution. It can be seen from Figure 3 that: compared with the reference axial temperature distribution, the sealing performance deteriorates at 7.5 meters from the starting position in the axial temperature distribution.

[0047] Since the moisture diffusion direction is from the side with a higher moisture concentration to the side with a lower moisture concentration, and the external humidity and the humidity of the cable body are not fixed and unchanged. Therefore, in some embodiments of the present invention, as Figure 4 shown, step S103 includes: S401. Determine the moisture diffusion direction of the cable body and the humidity judgment strategy corresponding to the moisture diffusion direction.

[0048] The moisture diffusion direction includes diffusion into the cable body and diffusion into the cable body. Specifically, when the external humidity is greater than the internal humidity of the cable body, the moisture diffusion direction is diffusion into the cable body, and when the external humidity is less than the internal humidity of the cable body, the moisture diffusion direction is diffusion into the cable body.

[0049] Since different moisture diffusion directions will lead to different distribution gradients of axial humidity distribution, it is necessary to set a humidity judgment strategy based on the moisture diffusion direction.

[0050] S402: Determine a second position based on a humidity determination strategy.

[0051] The embodiment of the present invention uses the moisture diffusion direction as a reference factor to determine the humidity judgment strategy, thereby further improving the monitoring accuracy of the second position.

[0052] In a specific embodiment of the present invention, when the moisture diffusion direction is the conduction direction toward the outside of the cable body, the humidity judgment strategy is: the humidity value in the axial humidity distribution corresponding to the second position is greater than the reference humidity value in the reference axial humidity distribution corresponding to the second position; When the moisture diffusion direction is the conduction direction toward the inside of the cable body, the humidity judgment strategy is: the humidity value in the axial humidity distribution corresponding to the second position is less than the reference temperature value in the reference axial humidity distribution corresponding to the second position.

[0053] In summary, if the outside humidity is greater than the internal humidity, the moisture will diffuse inward, and the relative humidity at the location where the sealing performance is reduced will be greater than that at other locations; if the outside humidity is lower than the internal humidity, the moisture will diffuse outward, and the relative humidity at the location where the sealing performance is reduced will be lower than that at other locations.

[0054] In a specific embodiment of the present invention, step S402 includes: When the moisture diffusion direction is the conduction direction toward the outside of the cable body, determine the first target area where the humidity value in the axial humidity distribution is less than the reference humidity value in the reference axial humidity distribution; determine whether the humidity difference between the humidity value and the reference humidity value in the first target area is greater than the preset humidity; if greater, take the position of the maximum humidity value in the humidity value as the second position; When the moisture diffusion direction is the conduction direction toward the inside of the cable body, determine the second target area in which the humidity value in the axial humidity distribution is greater than the reference humidity value in the reference axial humidity distribution; judge whether the humidity difference between the humidity value in the second target area and the reference humidity value is greater than the preset humidity; if greater, take the position where the minimum humidity value in the humidity value is located as the second position.

[0055] In a specific embodiment of the present invention, taking the diffusion direction of moisture as diffusion toward the outside of the cable body as an example, Figure 5 As shown,Figure 5 The abscissa therein is the position of the cable body, the ordinate is the humidity, the black line is the reference axial humidity distribution, and the red line is the axial humidity distribution. From Figure 5 it can be seen that: compared with the reference axial humidity distribution, the axial humidity distribution shows a decrease in sealing performance at 7.5 meters from the starting position.

[0056] From Figure 3 and Figure 5 it is known that: the first position and the second position are the same, so it can be concluded that the sealing performance of the cable body decreases at 7.5 meters from the starting position.

[0057] Since the cable body is a three-dimensional structure, when its sealing performance decreases, its radial temperature distribution will also change. Based on this characteristic, in some embodiments of the present invention, in order to further improve the reliability of judging the sealing performance of the protective layer, as Figure 6 shown, the method for monitoring the sealing performance of the cable protective layer further includes: S601. Obtain the radial temperature distribution at the first position and the reference radial temperature distribution; S602. Determine the temperature deformation region and the temperature deformation direction in the radial temperature distribution based on the reference radial temperature distribution.

[0058] Among them, the temperature deformation direction includes inward depression and outward protrusion.

[0059] S603. Determine the heat conduction direction of the cable body based on the radial temperature distribution, and determine whether the sealing performance of the temperature deformation region decreases based on the heat conduction direction and the temperature deformation direction.

[0060] Among them, when the heat conduction direction is towards the inside of the cable body and the temperature deformation direction is inward depression, it is determined that the sealing performance decreases. When the heat conduction direction is towards the outside of the cable body, the temperature deformation direction is outward protrusion.

[0061] In a specific embodiment of the present invention, as Figure 7 shown, Figure 7 the left figure (a) therein is the reference radial temperature distribution. From the reference radial temperature distribution, it can be obtained that the heat conduction direction is towards the inside of the cable body. Figure 7 The right figure (b) is the radial temperature distribution. From Figure 7 the right figure, it can be seen that: there is an inward depression region, indicating that the sealing performance of the depression region decreases.

[0062] Furthermore, when the sealing performance of the cable body decreases, its radial humidity distribution will also change. Therefore, in order to further improve the reliability of monitoring the sealing performance, in some embodiments of the present invention, as Figure 8As shown, the cable protection layer sealing performance monitoring method further includes: S801. Obtain the radial humidity distribution and the reference radial humidity distribution at the first position; S802. Determine the humidity deformation region and the humidity deformation direction in the radial humidity distribution based on the reference radial humidity distribution.

[0063] Similarly, the humidity deformation direction includes inward depression and outward bulge.

[0064] S803. Determine the moisture diffusion direction of the cable body based on the humidity temperature distribution, and determine whether the sealing performance of the humidity deformation region has decreased based on the moisture diffusion direction and the humidity deformation direction.

[0065] Wherein, when the moisture diffusion direction is diffusing outward from the cable body, the relative humidity at the sealing performance degradation position is lower than that at other positions, and the temperature deformation direction is outward bulge; when the moisture diffusion direction is diffusing inward into the cable body, the relative humidity at the sealing performance degradation position is higher than that at other positions, and the temperature deformation direction is inward depression.

[0066] In a specific embodiment of the present invention, as Figure 9 shown, Figure 9 in the left figure (a) is the reference radial humidity distribution. From the reference radial humidity distribution, it can be obtained that the moisture diffusion direction is diffusing outward from the cable body. Figure 9 The right figure (b) is the radial humidity distribution. From Figure 9 the right figure, it can be seen that there is an outward bulge region, indicating that the sealing performance has decreased in the bulge region.

[0067] It should be noted that: only when the monitoring results of the radial temperature distribution and the radial humidity distribution, and the axial temperature distribution and the axial humidity distribution all show a decrease in the sealing performance, it is determined that the sealing performance of the cable body has decreased. Moreover, the temperature deformation region and the humidity deformation region need to be the same. And the temperature deformation region and the humidity deformation region are the radial positions where the sealing performance has decreased. Through the radial position and the axial position of the first position / second position, the accurate positioning of the sealing performance can be achieved.

[0068] In summary, the cable protection layer sealing performance monitoring method proposed in the embodiments of the present invention not only monitors whether the sealing performance of the protection layer has decreased based on the physical quantities in two dimensions of temperature and humidity, improving the monitoring reliability, but also further verifies the monitoring results of the sealing performance by using the distributions in two directions of radial and axial respectively, further ensuring the reliability and accuracy of the sealing performance monitoring results. Further, through the two directions of radial and axial, the accurate positioning of the sealing performance degradation position can also be achieved, facilitating the safety maintenance of the bridge and improving the response ability to accidents caused by bridge structure changes.

[0069] To better implement the cable protection layer sealing performance monitoring method in the embodiments of the present invention, correspondingly, based on the cable protection layer sealing performance monitoring method, the embodiments of the present invention further provide a cable protection layer sealing performance monitoring device, as Figure 10 shown, the cable protection layer sealing performance monitoring device 1000 includes: A temperature and humidity distribution acquisition unit 1001, configured to acquire the axial temperature distribution and axial humidity distribution of the cable body. The cable body includes cable strands and a protection layer wrapping the cable strands; A sealing performance temperature monitoring unit 1002, configured to determine a first position where the sealing performance of the protection layer deteriorates based on the axial temperature distribution and a reference axial temperature distribution; A sealing performance humidity monitoring unit 1003, configured to determine a second position where the sealing performance of the protection layer deteriorates based on the axial humidity distribution and a reference axial humidity distribution; A sealing performance determination unit 1004, configured to determine that the sealing performance of the protection layer deteriorates when the first position and the second position are the same.

[0070] The cable protection layer sealing performance monitoring device 1000 provided in the above embodiments can implement the technical solutions described in the embodiments of the cable protection layer sealing performance monitoring method. For the specific implementation principles of the above modules or units, reference can be made to the corresponding content in the embodiments of the cable protection layer sealing performance monitoring method, which will not be elaborated here.

[0071] Those skilled in the art can understand that all or part of the processes for implementing the methods in the above embodiments can be completed by instructing relevant hardware (such as a processor, a controller, etc.) through a computer program. The computer program can be stored in a computer-readable storage medium. Among them, the computer-readable storage medium is a magnetic disk, an optical disk, a read-only memory, or a random access memory, etc.

[0072] The above has introduced in detail a cable protection layer sealing performance monitoring method and device provided by the present invention. Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present invention; at the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for monitoring the sealing performance of a cable protective layer, characterized in that: include: Acquire an axial temperature distribution and an axial humidity distribution of a cable body, wherein the cable body comprises strands and a protective layer wrapping the strands; determining a first position where the sealing performance of the protective layer decreases based on the axial temperature distribution and a reference axial temperature distribution; determining a second position where the sealing performance of the protective layer decreases based on the axial humidity distribution and a reference axial humidity distribution; When the first position and the second position are the same, it is determined that the sealing performance of the protective layer is degraded.

2. The cable protective layer sealing performance monitoring method according to claim 1 is characterized in that: The determining, based on the axial temperature distribution and the reference axial temperature distribution, a first position where the sealing performance of the protective layer decreases comprises: Determining the heat conduction direction of the cable body and a temperature judgment strategy corresponding to the heat conduction direction; The first position is determined based on the temperature determination strategy.

3. The cable protective layer sealing performance monitoring method according to claim 2 is characterized in that: The heat conduction direction includes a conduction direction toward the inside of the cable body and a conduction direction toward the outside of the cable body; When the heat conduction direction is the heat conduction direction toward the inside of the cable body, the temperature judgment strategy is: the temperature value in the axial temperature distribution corresponding to the first position is less than the reference temperature value in the reference axial temperature distribution corresponding to the first position; When the heat conduction direction is toward the outside of the cable body, the temperature judgment strategy is: the temperature value in the axial temperature distribution corresponding to the first position is greater than the reference temperature value in the reference axial temperature distribution corresponding to the first position.

4. The cable protective layer sealing performance monitoring method according to claim 3 is characterized in that: The determining the first position based on the temperature judgment strategy includes: When the heat conduction direction is the direction of conduction toward the inside of the cable body, determine a first candidate area in which the temperature value in the axial temperature distribution is less than the reference temperature value in the reference axial temperature distribution; determine whether the temperature difference between the temperature value and the reference temperature value in the first candidate area is greater than a preset difference; if greater, take the position where the minimum temperature value in the temperature values ​​is located as the first position; When the heat conduction direction is the conduction direction toward the outside of the cable body, determine a second candidate area in which the temperature value in the axial temperature distribution is greater than the reference temperature value in the reference axial temperature distribution; judge whether the temperature difference between the temperature value and the reference temperature value in the second candidate area is greater than a preset difference; if greater, take the position of the maximum temperature value in the temperature values ​​as the first position.

5. The cable protective layer sealing performance monitoring method according to claim 1 is characterized in that: The determining, based on the axial humidity distribution and the reference axial humidity distribution, a second position where the sealing performance of the protective layer decreases comprises: Determining the moisture diffusion direction of the cable body and a humidity judgment strategy corresponding to the moisture diffusion direction; The second position is determined based on the humidity determination strategy.

6. The cable protective layer sealing performance monitoring method according to claim 5 is characterized in that: The moisture diffusion direction includes diffusion toward the inside of the cable body and diffusion toward the outside of the cable body; When the moisture diffusion direction is the conduction direction toward the outside of the cable body, the humidity judgment strategy is: the humidity value in the axial humidity distribution corresponding to the second position is greater than the reference humidity value in the reference axial humidity distribution corresponding to the second position; When the moisture diffusion direction is the conduction direction toward the inside of the cable body, the humidity judgment strategy is: the humidity value in the axial humidity distribution corresponding to the second position is less than the reference temperature value in the reference axial humidity distribution corresponding to the second position.

7. The cable protective layer sealing performance monitoring method according to claim 6 is characterized in that: The determining the second position based on the humidity judgment strategy includes: When the moisture diffusion direction is the conduction direction toward the outside of the cable body, determine a first target area where the humidity value in the axial humidity distribution is less than the reference humidity value in the reference axial humidity distribution; determine whether the humidity difference between the humidity value and the reference humidity value in the first target area is greater than a preset humidity; if greater, take the position of the maximum humidity value in the humidity value as the second position; When the moisture diffusion direction is the conduction direction toward the inside of the cable body, determine a second target area in which the humidity value in the axial humidity distribution is greater than the reference humidity value in the reference axial humidity distribution; determine whether the humidity difference between the humidity value and the reference humidity value in the second target area is greater than the preset humidity; if greater, take the position of the minimum humidity value in the humidity values ​​as the second position.

8. The cable protective layer sealing performance monitoring method according to claim 1 is characterized in that: The method further comprises: Acquire the radial temperature distribution of the first position and a reference radial temperature distribution; determining a temperature deformation region and a temperature deformation direction in the radial temperature distribution based on the reference radial temperature distribution; The heat conduction direction of the cable body is determined based on the radial temperature distribution, and whether the sealing performance of the temperature deformation area is reduced is determined based on the heat conduction direction and the temperature deformation direction.

9. The cable protective layer sealing performance monitoring method according to claim 1, characterized in that: The method further comprises: Acquire the radial humidity distribution of the first position and a reference radial humidity distribution; determining a humidity deformation region and a humidity deformation direction in the radial humidity distribution based on the reference radial humidity distribution; The moisture diffusion direction of the cable body is determined based on the humidity temperature distribution, and whether the sealing performance of the humidity deformation area is reduced is determined based on the moisture diffusion direction and the humidity deformation direction.

10. A cable protective layer sealing performance monitoring device, characterized in that: include: A temperature and humidity distribution acquisition unit, used to acquire the axial temperature distribution and axial humidity distribution of a cable body, wherein the cable body comprises a cable strand and a protective layer wrapping the cable strand; a sealing performance temperature monitoring unit, configured to determine a first position where the sealing performance of the protective layer decreases based on the axial temperature distribution and a reference axial temperature distribution; a sealing performance humidity monitoring unit, configured to determine a second position where the sealing performance of the protective layer decreases based on the axial humidity distribution and a reference axial humidity distribution; The sealing performance determining unit is used to determine that the sealing performance of the protective layer decreases when the first position and the second position are the same.

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