A pipeline stress detection method based on soil moisture content

Abstract

The present invention provides a pipeline stress detection method based on soil moisture content, which simulates different moisture contents in the soil by pumping water on the soil surface above the buried pipe section, considers the water loss rate in the soil, and clarifies the influence of the moisture content in the soil on the magnetic field data above the buried pipe section, thereby obtaining the relationship between the position of each detection point on the buried pipe section and the magnetic field data at the position of each detection point under different soil moisture contents. Based on the relationship between the position of each detection point on the buried pipe section and the magnetic field data at the position of each detection point and the moisture content of the soil above the pipe section to be detected, the stress distribution information on the pipe section to be detected can be determined, and the influence of the moisture content of the soil above the detection pipe section on the stress detection of the pipe section to be detected can be eliminated, thereby improving the accuracy of the stress detection of the pipe section to be detected.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline nondestructive testing, and in particular to a pipeline stress detection method based on soil moisture content. Background Art

[0002] Pipeline transportation is the main way to transport oil and natural gas. However, stress concentration is very likely to occur during the operation of the pipeline. When the stress on the pipeline exceeds the yield limit of the pipeline material, plastic deformation or cracks may occur on the pipeline, seriously affecting the safe operation of the pipeline. Therefore, effective detection of pipeline stress is a necessary measure to avoid safety accidents.

[0003] At present, the stress distribution on the pipeline can be detected based on weak magnetic detection technology. That is, the stress state of the pipeline material is evaluated by using the natural magnetomechanical relationship of the stress concentration area to make early predictions and assessments of the pipeline stress concentration area.

[0004] However, since the weak magnetic detection signal is weak and easily interfered by external signals, for example, it is easily interfered by the water content in the covering soil on the pipeline. Therefore, in the process of detecting the stress distribution on the pipeline based on the weak magnetic stress detection technology, great interference and uncertainty are prone to occur, which reduces the accuracy of pipeline stress detection. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a pipeline stress detection method based on soil moisture content, which can improve the accuracy of pipeline stress detection.

[0006] The technical solution of the present invention to solve the above technical problems is as follows:

[0007] In a first aspect, the present invention provides a pipeline stress detection method based on soil moisture content, in which a detection point is set at a preset distance above the buried pipe section, and the initial magnetic field data of each detection point position is obtained. Wherein, there is soil above the buried pipe section. Water is injected into the soil in equal amounts N times, and the real-time magnetic field data of each detection point position after each water injection into the soil is detected. Wherein, there is water accumulation on the soil surface after the Nth water injection into the soil. The actual water increment in the soil after the i-th water injection into the soil is calculated. Wherein, the actual water increment is determined based on the total water injection amount of the first to i-th water injection into the soil and the water loss in the soil during the first to i-th water injection into the soil; the water loss in the soil during the first to i-th water injection into the soil is determined based on soil information; 1≤i≤N. Based on the initial magnetic field data and real-time magnetic field data of each detection point position, and the actual water increment in the soil after each water injection into the soil, a first functional relationship is obtained. The first functional relationship includes the relationship between the position of each detection point and the magnetic field data at the position of each detection point when the amount of water injected into the soil is different. Based on the first functional relationship, the second functional relationship is determined. The second functional relationship includes the relationship between the position of each detection point and the magnetic field data at the position of each detection point when the water content of the soil is different. Based on the water content of the soil above the pipe section to be detected and the second functional relationship, the stress distribution information on the pipe section to be detected is determined.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Further, the detection area is determined. The detection area is a cylindrical area, and the line connecting the center of the circle on the upper surface of the detection area and the center of gravity of the buried pipe section is perpendicular to the horizontal plane. The radius of the detection area is equal to the sum of the distance between the center of gravity of the buried pipe section and the end point of the buried pipe section and the preset distance. The upper surface of the detection area coincides with the upper surface of the soil. The lower surface of the detection area is the plane where the top of the buried pipe section is located. The detection point is located in the detection area. The soil in the detection area is sampled to obtain soil information. The soil information includes the number of pores in the soil, the proportion of large pores, the proportion of medium pores, the proportion of small pores, the water conductivity of large pores, the water conductivity of medium pores and the water conductivity of small pores. The pore size of the large pores is within the first preset range, the pore size of the medium pores is within the second preset range, and the pore size of the small pores is within the third preset range. The values ​​within the first preset range are all greater than the values ​​within the second preset range, and the values ​​within the second preset range are all greater than the values ​​within the third preset range.

[0010] Further, based on the soil information and the first preset relationship, the water conductivity of the soil is calculated. The first preset relationship includes:

[0011] ;

[0012] in, is the water conductivity of the soil, is the number of pores, is the proportion of macropores, is the proportion of mesopores, is the proportion of small pores, ; is the macropore water conductivity, is the mesopore water conductivity, is the water conductivity of small pores.

[0013] Based on the second preset relationship, the horizontal moisture flux and the vertical moisture flux in the detection area are obtained. The second preset relationship includes:

[0014] ;

[0015] ;

[0016] in, is the horizontal moisture flux in the detection area, is the vertical moisture flux in the detection area, is the surface area of ​​the detection area, is the bottom area of ​​the detection area.

[0017] Based on the horizontal moisture flux in the detection area, the vertical moisture flux in the detection area and the third preset relationship, the water loss in the soil during the first to i-th water injection into the soil is calculated. The third preset relationship includes:

[0018] ;

[0019] in, is the amount of water lost in the soil during the first to i-th water injection process, is the time when the real-time magnetic field data of each detection point is detected after the i-th water injection into the soil. The starting time of the first water injection into the soil;

[0020] Based on the total water injection amount of the first to i-th water injections into the soil, the water loss in the soil during the first to i-th water injections into the soil, and the fourth preset relationship, the actual water increment in the soil after the i-th water injection into the soil is calculated. The fourth preset relationship includes:

[0021] ;

[0022] in, is the actual water increment in the soil after the i-th water injection into the soil, The amount of water injected into the soil each time.

[0023] Furthermore, the detection area is isolated from the non-detection area, and water is injected into the soil in the detection area in equal amounts N times.

[0024] Further, soil on the buried pipe section and water around the buried pipe section are removed. Stress values ​​and magnetic field data corresponding to the stress concentration position on the buried pipe section are obtained. Based on the stress values ​​and magnetic field data corresponding to the stress concentration position on the buried pipe section, the first functional relationship is corrected. Based on the corrected first functional relationship, a second functional relationship is determined.

[0025] Furthermore, when it is detected that there is a spatially scattered magnetic field above the buried pipe section, the spatially scattered magnetic field is offset based on a reverse magnetic field corresponding to the spatially scattered magnetic field.

[0026] Furthermore, the pipe section to be inspected has the same pipe section type as the buried pipe section. The pipe section type is determined based on at least one of the corresponding pipe section's material, model, environmental information of the environment, commissioning time, service time, design pressure, operating pressure, and type of transported medium.

[0027] The beneficial effects of the present invention are as follows: by pumping water on the soil surface above the buried pipe section, simulating different water contents in the soil, considering the water loss rate in the soil, clarifying the influence of the water content in the soil on the magnetic field data above the buried pipe section, and thus obtaining the relationship between the position of each detection point on the buried pipe section and the magnetic field data at the position of each detection point under different soil water contents. Based on the relationship between the position of each detection point on the buried pipe section and the magnetic field data at the position of each detection point and the water content of the soil above the pipe section to be detected, the stress distribution information on the pipe section to be detected can be determined, and the influence of the water content of the soil above the detection pipe section on the stress detection of the pipe section to be detected can be eliminated, thereby improving the accuracy of the stress detection of the pipe section to be detected.

[0028] In a second aspect, the present invention provides an electronic device, comprising: a memory, one or more processors; the memory and the processor are coupled; wherein the memory stores computer program code, the computer program code includes computer instructions, and when the computer instructions are executed by the processor, the electronic device executes the pipeline stress detection method based on soil moisture content as described in any one of the above-mentioned first aspects.

[0029] In a third aspect, a computer-readable storage medium is provided, comprising computer instructions. When the computer instructions are executed on an electronic device, the electronic device executes the pipeline stress detection method based on soil moisture content as described in any one of the first aspects.

[0030] In a fourth aspect, a computer program product is provided. When the computer program product is run on a computer, the computer is enabled to execute the pipeline stress detection method based on soil moisture content as described in any one of the first aspects.

[0031] It can be understood that the beneficial effects that can be achieved by the electronic device of the second aspect, the computer-readable storage medium of the third aspect, and the computer program product of the fourth aspect provided above can be referred to the beneficial effects in the first aspect and any possible design method thereof, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of a pipeline stress detection method based on soil moisture content provided by the present invention;

[0033] Figure 2 A schematic diagram of a detection area provided by the present invention. DETAILED DESCRIPTION

[0034] The technical solution in the embodiment of the present application will be described below in conjunction with the drawings in the embodiment of the present application. Among them, in the description of the present application, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship, for example, A / B can represent A or B; "and / or" in the present application is only a description of the association relationship of the associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. And, in the description of the present application, unless otherwise specified, "multiple" refers to two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple. In addition, in order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second" and the like are used to distinguish between the same items or similar items with substantially the same functions and effects. Those skilled in the art will understand that the words "first", "second" and the like do not limit the quantity and execution order, and the words "first", "second" and the like do not necessarily limit the differences. At the same time, in the embodiments of the present application, the words "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or design.

[0035] The present invention provides a pipeline stress detection method based on soil moisture content, see Figure 1 The method comprises the following steps S101-S106:

[0036] S101: setting a detection point at a preset distance above the buried pipe section, and acquiring initial magnetic field data at the position of each detection point.

[0037] Among them, there is soil above the buried pipe section.

[0038] In some embodiments, in order to improve the accuracy of detection, before executing step S101, the following steps may be further performed to reduce interference with detection.

[0039] In some embodiments, it is possible to detect whether there is an influence of a spatially scattered magnetic field above the buried pipe section. If it is detected that there is a spatially scattered magnetic field above the buried pipe section, the spatially scattered magnetic field can be offset based on the reverse magnetic field corresponding to the spatially scattered magnetic field.

[0040] In some embodiments, the detection area can be predetermined. Figure 2 , the detection area 200 is a cylindrical area, and the line connecting the center O of the upper surface of the detection area 200 and the center of gravity O' of the buried pipe section 201 is perpendicular to the horizontal plane. The radius R of the detection area 200 is equal to the sum of the distance between the center of gravity O' of the buried pipe section 201 and the end point A of the buried pipe section 201 and the preset distance L. The upper surface of the detection area 200 coincides with the upper surface of the soil 202. The lower surface of the detection area 200 is the plane where the top of the buried pipe section is located. The detection point is located in the detection area 200.

[0041] For example, a pipeline locator can be used to detect and locate the pipe segment, and the route of the pipe segment can be measured using GPS based on the nearest reference point. The midpoint of the route of the pipe segment is taken as the center of the circle, the center of the circle is connected to the end point of the route of the pipe segment, and the connection line is extended outward by 50 As radius R, here , mark the circular track on the soil surface, and use a plastic plate that does not affect the magnetic field signal to form a circle on the soil surface along the track. The circle is used as the upper surface, and the area extending downward to the top of the pipe section is used as the detection area.

[0042] In some embodiments, the weather forecast information of the geographical location of the buried pipe section can be checked, and a cloudy day can be selected as the date of the on-site inspection. The advantage of selecting a cloudy day is that the temperature and air humidity are higher on a cloudy day than on a sunny day, the evaporation rate of the water on the soil surface is lower, the water content in the soil simulated by water injection is more stable, and water resources are saved.

[0043] S102: Inject water into the soil in equal amounts N times, and detect real-time magnetic field data at each detection point after each injection of water into the soil.

[0044] Among them, there is water accumulation on the soil surface after the Nth water injection into the soil.

[0045] In some embodiments, the detection area can be isolated from the non-detection area. For example, the detection area can be isolated from the non-detection area by a plastic plate. Afterwards, water is injected into the soil in the detection area in equal amounts N times.

[0046] In some embodiments, the real-time magnetic field data of each detection point after each water injection into the soil can be detected based on a weak magnetic detection method. The principle of the weak magnetic detection method is as follows:

[0047] Ferromagnetic materials generate self-generated magnetic fields under the action of the geomagnetic field, and the magnetic lines of the geomagnetic field can be nearly parallel to the buried horizontal pipeline. The self-generated magnetic field exists inside the pipeline material. Due to the inverse magnetostrictive effect, the deformation at the defects and stress concentrations will cause the size and direction of the self-generated magnetic field to change. Detecting the changes in the magnetic field can detect the presence of defects and stress concentrations.

[0048] Exemplarily, according to the weak magnetic detection method, a magnetic probe is used to step the distance Conduct non-contact inspection along the pipeline route and record the probe test starting point = , Step times 20 and the magnetic field data of the pipe section measured by the probe. Use a water pipe and a water pump to inject water into the detection area surrounded by the plastic board. The single injection volume =5L. Record the time when the first water injection begins Repeat the water injection steps until water begins to accumulate on the soil surface above the buried pipe section, then stop the water injection and record the first The set of time points at which the measurement ends after the first water injection is ={7:49;8:00;8:09;8:11;8:21;8:31}, cumulative pumping times =6.

[0049] S103: Calculate the actual water increment in the soil after the i-th water injection into the soil.

[0050] The actual water increment is determined based on the total water injection amount into the soil from the first to the i-th injection and the water loss in the soil during the first to the i-th injection. The water loss in the soil during the first to the i-th injection is determined based on soil information, 1≤i≤N.

[0051] In some embodiments, the water conductivity of the soil is calculated based on the soil information and the first preset relationship. The first preset relationship includes:

[0052] ;

[0053] in, is the water conductivity of the soil, is the number of pores, is the proportion of macropores, is the proportion of mesopores, is the proportion of small pores, ; is the macropore water conductivity, is the mesopore water conductivity, is the water conductivity of small pores.

[0054] In some embodiments, the soil in the detection area can be sampled to obtain soil information. The soil information includes the number of pores, the proportion of large pores, the proportion of medium pores, the proportion of small pores, the water conductivity of large pores, the water conductivity of medium pores, and the water conductivity of small pores. The pore size of the large pores is within the first preset range, the pore size of the medium pores is within the second preset range, and the pore size of the small pores is within the third preset range. The values ​​within the first preset range are all greater than the values ​​within the second preset range, and the values ​​within the second preset range are all greater than the values ​​within the third preset range.

[0055] For example, a soil sampler is used to sample the soil within the detection area (or outside the detection area). The soil within the radius is sampled to avoid affecting the soil content in the detection area), and the soil type detected is close to the soil within the water injection range; the ratio of sand, silt and clay is detected to determine the soil type, which is divided into loam.

[0056] From the data, we know that the porosity of clay is 45% to 60%, mainly capillary pores and inactive pores; the porosity of sand is 33% to 45%, with more aeration pores; the porosity of loam is 45% to 52%, with moderate aeration pores and more capillary pores. According to the pore size, it is divided into large pores (pore diameter greater than 100μm, that is, the first preset range is greater than 100μm), also called "ventilation pores" or "non-capillary pores", which have ventilation and drainage functions. Medium pores (pore diameter between 100μm and 30μm, that is, the second preset range is 100μm to 30μm) have water conductivity and fast capillary water movement. Small pores (pore diameter between 3μm and 30μm, that is, the third preset range is 3μm to 30μm) have water retention and slow capillary water movement.

[0057] The porosity of the sampled soil is determined to be 50%; the number of pores is obtained by multiplying the soil volume by the soil porosity, where f=π =14.13D, is the height of the detection area, which is determined by the subsequent excavation verification steps; the proportion of large pores 、The proportion of mesopores 、Proportion of small pores and macropore water conductivity , mesopore water conductivity , small pore water conductivity The relevant values ​​of can be determined by referring to the research results in the corresponding field, for example, , , , , , .

[0058] Based on the second preset relationship, the horizontal moisture flux and the vertical moisture flux in the detection area are obtained. The second preset relationship includes:

[0059] ;

[0060] ;

[0061] in, is the horizontal moisture flux in the detection area, is the vertical moisture flux in the detection area, is the surface area of ​​the detection area, is the bottom area of ​​the detection area. = , = ; is the radius of the detection area, is the height of the detection area.

[0062] Based on the horizontal moisture flux in the detection area, the vertical moisture flux in the detection area and the third preset relationship, the water loss in the soil during the first to i-th water injection into the soil is calculated. The third preset relationship includes:

[0063] ;

[0064] in, is the amount of water lost in the soil during the first to i-th water injection process, is the time when the real-time magnetic field data of each detection point is detected after the i-th water injection into the soil. The starting time of the first water injection into the soil;

[0065] Based on the total water injection amount of the first to i-th water injections into the soil, the water loss in the soil during the first to i-th water injections into the soil, and the fourth preset relationship, the actual water increment in the soil after the i-th water injection into the soil is calculated. The fourth preset relationship includes:

[0066] ;

[0067] in, is the actual water increment in the soil after the i-th water injection into the soil, The amount of water injected into the soil each time.

[0068] S104: Obtain a first functional relationship based on the initial magnetic field data and the real-time magnetic field data at each detection point, and the actual water increment in the soil after each water injection into the soil.

[0069] The first functional relationship includes the relationship between the position of each detection point and the magnetic field data at the position of each detection point when the amount of water injected into the soil is different.

[0070] S105: Determine a second functional relationship based on the first functional relationship.

[0071] The second functional relationship includes the relationship between the position of each detection point and the magnetic field data at the position of each detection point when the moisture content of the soil is different.

[0072] In some embodiments, soil on the buried pipe segment and water around the buried pipe segment are removed. Stress values ​​and magnetic field data corresponding to stress concentration locations on the buried pipe segment are obtained. Based on the stress values ​​and magnetic field data corresponding to stress concentration locations on the buried pipe segment, the first functional relationship is corrected. Based on the corrected first functional relationship, a second functional relationship is determined.

[0073] For example, the buried pipe section can be dug out. If there is water accumulation around the buried pipe section, a water pump can be used to pump out the water and measure the depth of the dug pit. . Measure and record the actual physical parameters of the pipe segment. For example, the curvature of the pipe segment is 261.76 , slope of 15°, slip of 0m. Afterwards, the stress condition of the pipe section can be detected using a contact magnetic detector, and the stress value and magnetic field data corresponding to the stress concentration position measured by the probe can be recorded; finally, the anti-corrosion layer of the pipeline can be removed, and the outer wall of the pipe section can be visually inspected to find defects, scratches and corrosion, and the depth and location of defects, scratches and corrosion can be measured and recorded. Based on the above information, the first functional relationship can be corrected.

[0074] In some embodiments, is the horizontal axis , the magnetic field data is the vertical coordinate , use MATLAB software to draw a certain water injection volume The scatter plot below interpolates the data and draws - Curve; Draw different water injection volumes in the same two-dimensional coordinate graph according to the detection order Next - The different colors of the curve represent different pumping volumes. is the starting point of the probe test, is the number of steps, is the stepping distance.

[0075] Based on the obtained stress concentration position, find the corresponding coordinates in the figure and obtain the water injection volume at each stress concentration point. Magnetic field data under water injection is the horizontal axis , the magnetic field data at the stress concentration point is the vertical coordinate , use the software MATLAB to draw a scatter plot, and according to the observed scatter plot characteristics, select the fitting function, fit the scatter data, and obtain different water injection volumes. The functional relationship between the magnetic field signal at the lower stress concentration and the water injection volume V is obtained to obtain the spatial distribution law of the magnetic field of the quantitative stress concentration affected by the introduction of water. That is, the second functional relationship is obtained.

[0076] S106: Determine stress distribution information on the pipe section to be inspected based on the water content of the soil above the pipe section to be inspected and the second functional relationship.

[0077] In some embodiments, the pipe segment to be detected is of the same type as the corresponding buried pipe segment. The pipe segment type is determined based on at least one of the material, model, environmental information of the environment, commissioning time, service time, design pressure, operating pressure, and type of the transport medium of the corresponding pipe segment.

[0078] For example, the oil and gas transportation pipeline database of the pipeline network can be queried to view the pipeline design, pipeline operation and operation documents, and obtain the pipeline construction and commissioning time, pipeline specifications, design pressure, operating pressure, pipeline material, anti-corrosion layer material, pipeline transportation medium, pipeline service time, pipeline environmental information along the pipeline and pipeline historical detection data, including pipeline geometric deformation detection data and pipeline internal detection data. Among them, the environmental information along the pipeline includes soil properties, pipeline passing rivers, cities, construction sites, etc. Based on the acquired data, the segment type of the corresponding pipeline segment can be determined.

[0079] Pipeline segment types include those with macroscopic stress concentration and those with microscopic stress concentration. Pipeline segments that may have macroscopic stress concentration can be determined based on the time when the pipeline was put into operation, pipeline specifications, design pressure, operating pressure, and pipeline service time. Pipe segments that may have microscopic stress concentration can be determined based on whether the pipeline transport medium is corrosive. Pipe segments that may have macroscopic stress concentration and microscopic stress concentration can be determined based on the environmental information along the pipeline.

[0080] Among them, the short radius of the stress action range of the macro stress concentration is greater than 1 The corresponding pipe sections can be classified into large curvature sections, span sections, lateral sliding sections and climbing sections. The short radius of the stress action range of micro stress concentration is less than 1 The corresponding pipe sections can be specifically classified according to the pipe sections with defects, scratches, and welds.

[0081] It can be seen that the present invention simulates different water contents in the soil by pumping water on the soil surface above the buried pipe section, considers the water loss rate in the soil, clarifies the influence of the water content in the soil on the magnetic field data above the buried pipe section, and thus obtains the relationship between the position of each detection point on the buried pipe section and the magnetic field data at the position of each detection point under different soil water contents. Based on the relationship between the position of each detection point on the buried pipe section and the magnetic field data at the position of each detection point and the water content of the soil above the pipe section to be detected, the stress distribution information on the pipe section to be detected can be determined, and the influence of the water content of the soil above the detection pipe section on the stress detection of the pipe section to be detected can be eliminated, thereby improving the accuracy of the stress detection of the pipe section to be detected.

[0082] In some schemes, multiple embodiments of the present application can be combined, and the combined scheme can be implemented. Optionally, some operations in the process of each method embodiment are optionally combined, and / or the order of some operations is optionally changed. In addition, the execution order between the steps of each process is only exemplary and does not constitute a restriction on the execution order between the steps. There can also be other execution orders between the steps. It is not intended to indicate that the execution order is the only order in which these operations can be performed. A person of ordinary skill in the art will think of a variety of ways to reorder the operations described herein. In addition, it should be noted that the process details involved in a certain embodiment of this article are also applicable to other embodiments in a similar manner, or different embodiments can be used in combination.

[0083] In addition, some steps in the method embodiment may be equivalently replaced by other possible steps. Alternatively, some steps in the method embodiment may be optional and may be deleted in certain usage scenarios. Alternatively, other possible steps may be added to the method embodiment. Furthermore, the method embodiments may be implemented separately or in combination.

[0084] In the several embodiments provided in this application, it should be understood that the disclosed methods can be implemented in other ways.

[0085] The technical solution of the embodiment of the present application may be essentially or in other words, the part that contributes or all or part of the technical solution may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a device (which may be a single-chip microcomputer, chip, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0086] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application shall be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A pipeline stress detection method based on soil moisture content, characterized in that: include: A detection point is set at a preset distance above the buried pipe section to obtain initial magnetic field data at each detection point; There is soil above the buried pipe section; Injecting water into the soil in equal amounts N times, and detecting real-time magnetic field data of the positions of the detection points after each injection of water into the soil; wherein water accumulates on the soil surface after the Nth injection of water into the soil; Calculating the actual water increment in the soil after the i-th water injection into the soil; the actual water increment is determined based on the total water injection amount into the soil from the first to the i-th water injection into the soil and the water loss amount in the soil during the first to the i-th water injection into the soil; the water loss amount in the soil during the first to the i-th water injection into the soil is determined based on soil information; 1≤i≤N; Based on the initial magnetic field data and the real-time magnetic field data at the position of each detection point, and the actual water increment in the soil after each water injection into the soil, a first functional relationship is obtained; the first functional relationship includes the relationship between the position of each detection point and the magnetic field data at the position of each detection point when the amount of water injected into the soil is different; Based on the first functional relationship, determining a second functional relationship; the second functional relationship includes a relationship between the position of each of the detection points and the magnetic field data at the position of each of the detection points when the moisture content of the soil is different; Based on the water content of the soil above the pipe section to be inspected and the second functional relationship, the stress distribution information on the pipe section to be inspected is determined.

2. The method according to claim 1, characterized in that Before setting a detection point at a preset distance above the buried pipe section and obtaining initial magnetic field data at each detection point, the method further includes: Determine a detection area; the detection area is a cylindrical area, and the line connecting the center of the upper surface of the detection area and the center of gravity of the buried pipe section is perpendicular to the horizontal plane; the radius of the detection area is equal to the sum of the distance between the center of gravity of the buried pipe section and the end point of the buried pipe section and a preset distance; the upper surface of the detection area coincides with the upper surface of the soil; the lower surface of the detection area is the plane where the top of the buried pipe section is located; the detection point is located within the detection area; The soil in the detection area is sampled to obtain soil information; the soil information includes the number of pores, the proportion of large pores, the proportion of medium pores, the proportion of small pores, the water conductivity of large pores, the water conductivity of medium pores and the water conductivity of small pores of the soil; the pore size of the large pores is within a first preset range, the pore size of the medium pores is within a second preset range, and the pore size of the small pores is within a third preset range; the values ​​within the first preset range are all greater than the values ​​within the second preset range; the values ​​within the second preset range are all greater than the values ​​within the third preset range.

3. The method according to claim 2, characterized in that The calculating the actual water increment in the soil after the i-th water injection into the soil comprises: Based on the product of i and the amount of water injected into the soil each time, the total amount of water injected into the soil from the 1st to the ith time is obtained as follows; The water conductivity of the soil is calculated based on the soil information and a first preset relationship; the first preset relationship includes: ； in, is the water conductivity of the soil, is the number of pores, is the percentage of macropores, is the proportion of the mesopores, is the percentage of small pores, ; is the macropore water conductivity, is the mesopore water conductivity, is the water conductivity rate of the small pores; Based on a second preset relationship, the horizontal moisture flux and the vertical moisture flux in the detection area are obtained; the second preset relationship includes: ； ； in, is the horizontal moisture flux in the detection area, is the vertical moisture flux in the detection area, is the surface area of ​​the detection region, is the bottom area of ​​the detection area; The amount of water lost in the soil during the first to i-th water injection into the soil is calculated based on the horizontal water flux in the detection area, the vertical water flux in the detection area, and a third preset relationship; the third preset relationship includes: ； in, is the amount of water lost in the soil during the first to i-th water injection into the soil, is the time when the detection of the real-time magnetic field data at each detection point is completed after the i-th water injection into the soil, is the starting time of the first water injection into the soil; Based on the total amount of water injected into the soil from the first to the i-th time, the amount of water lost in the soil during the first to the i-th water injection into the soil, and a fourth preset relationship, the actual water increment in the soil after the i-th water injection into the soil is calculated; the fourth preset relationship includes: ； in, is the actual water increment in the soil after water is injected into the soil for the i-th time, The amount of water injected into the soil each time.

4. The method according to claim 3, characterized in that The step of injecting water into the soil in equal amounts for N times comprises: isolating the detection area from the non-detection area; Water is injected into the soil in the detection area in equal amounts in N times.

5. The method according to claim 4, characterized in that The determining of the second functional relationship based on the first functional relationship includes: removing soil on the buried pipe section and accumulated water around the buried pipe section; Obtaining stress values ​​and magnetic field data corresponding to stress concentration positions on the buried pipe section; Correcting the first functional relationship based on stress values ​​and magnetic field data corresponding to the stress concentration position on the buried pipe section; The second functional relationship is determined based on the corrected first functional relationship.

6. The method according to claim 5, characterized in that Before setting a detection point at a preset distance above the buried pipe section and obtaining initial magnetic field data at each detection point, the method further includes: When it is detected that there is a spatially scattered magnetic field above the buried pipe section, the spatially scattered magnetic field is offset based on a reverse magnetic field corresponding to the spatially scattered magnetic field.

7. The method according to claim 6, characterized in that The pipe section to be inspected is of the same pipe section type as that corresponding to the buried pipe section; the pipe section type is determined based on at least one of the material, model, environmental information of the environment in which it is located, commissioning time, service time, design pressure, operating pressure, and type of conveying medium of the corresponding pipe section.

8. An electronic device, characterized in that: include: A memory and one or more processors; the memory is coupled to the processor; wherein the memory stores computer program code, the computer program code includes computer instructions, and when the computer instructions are executed by the processor, the electronic device executes the pipeline stress detection method based on soil moisture content as described in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that: It comprises computer instructions, and when the computer instructions are executed on an electronic device, the electronic device executes the pipeline stress detection method based on soil moisture content as described in any one of claims 1 to 7.

10. A computer program product, characterized in that When the computer program product is run on a computer, the computer is enabled to execute the pipeline stress detection method based on soil moisture content according to any one of claims 1 to 7.

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