Underground pipeline detection data acquisition method and system

Abstract

The invention belongs to the technical field of data acquisition, and provides an underground pipeline detection data acquisition method and system, and the method comprises the following steps: collecting underground pipeline drawing data of a target region, and determining the information parameters of underground pipelines; performing field exploration, marking a ground outcrop point of the underground pipeline, and preliminarily judging the trend of the pipeline; detecting the underground pipeline through an electromagnetic method or a ground penetrating radar, and determining the position and the burial depth of the underground pipeline; reflected and scattered sound wave signals propagated through the internal fluid of the underground pipeline are collected through sound wave detection, and the state of the internal fluid is evaluated; fusing different detection data to generate an underground pipeline space model; by comprehensively using the electromagnetic method, the ground penetrating radar and the sound wave detection technology, the position, the burial depth and the internal fluid state information of the underground pipeline can be comprehensively collected, the physical position of the pipeline is determined, the state of the internal fluid of the pipeline is evaluated, and the accuracy and the reliability of the detection result are effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of data acquisition, and more specifically, it is a method and system for underground pipeline detection data acquisition. Background Art

[0002] In the process of current urban construction and development, underground pipelines are like the "lifelines" of cities, and their safe and efficient operation is crucial.

[0003] However, traditional underground pipeline detection methods generally adopt single or limited combined detection methods. The electromagnetic detection technology mainly relies on the electromagnetic characteristics of pipelines, and its applicable range is affected by pipeline materials, burial depths, and surrounding soil types. In the detection of some non-metallic pipelines or deeply buried pipelines, the effectiveness of the electromagnetic method is low, and it is easy to produce missed detections or misjudgments. In addition, for some soils with high electrical conductivity (such as wet areas), the transmission of electromagnetic signals will be severely interfered, resulting in inaccurate detection results.

[0004] Moreover, traditional detection methods often neglect the acquisition of information on the fluid state inside pipelines. The state of the fluid inside the pipeline is crucial for evaluating the operation status of the pipeline, predicting potential failures, and formulating maintenance strategies. However, existing detection technologies usually can only provide the physical location information of the pipeline and cannot directly obtain the state of the fluid inside the pipeline.

[0005] At the same time, traditional underground pipeline detection methods often adopt a single detection means and lack a data fusion and processing mechanism. This leads to possible errors in the collected data and cannot fully utilize the complementary advantages of different detection technologies.

[0006] Therefore, those skilled in the art have proposed a method and system for underground pipeline detection data acquisition, aiming to comprehensively use electromagnetic methods, ground-penetrating radar, and acoustic detection technologies, and fuse the data obtained from different detection technologies to improve the accuracy and reliability of detection results. Summary of the Invention

[0007] To solve the above technical problems, the present invention provides a method and system for underground pipeline detection data acquisition to solve the problems raised in the background art.

[0008] According to the first aspect of the present disclosure, a method for underground pipeline detection data acquisition is proposed, including the following steps:

[0009] S1. Based on the drawing materials of underground pipelines in the target area, determine the information parameters of the underground pipelines;

[0010] S2. Obtain pipeline alignment data; the pipeline alignment data is obtained by marking the ground outcrop points of underground pipelines based on on-site exploration.

[0011] S3. Obtain the location and burial depth data of the underground pipelines; the location and burial depth data are obtained based on electromagnetic method or ground penetrating radar;

[0012] S4. Obtain the reflected and scattered acoustic wave signals after propagating through the internal fluid of the underground pipelines, and evaluate the internal fluid state. The reflected and scattered acoustic wave signals are obtained based on acoustic wave detection;

[0013] S5. Integrate the detected data to generate a spatial model of the underground pipelines.

[0014] Preferably, the information parameters of the underground pipelines include the pipeline material, the size of the pipe diameter, and the type of the transported fluid. The pipeline materials include metal pipelines and non-metal pipelines.

[0015] Preferably, the ground outcrop points of the underground pipelines include valve wells, inspection wells, fire hydrants, and pipeline vent holes.

[0016] Mark the location of the underground pipelines on the ground with marking paint, and use a GPS locator to record the accurate coordinates. According to the distribution of the ground outcrop points and the collected underground pipeline drawings, obtain the preliminary pipeline alignment;

[0017] The obtaining of the pipeline alignment data further includes:

[0018] Assist in judging the pipeline alignment based on the ground markings.

[0019] Preferably, the electromagnetic method for detecting underground pipelines is used for metal pipelines. Obtaining the location and burial depth data of underground pipelines based on the electromagnetic method includes:

[0020] Place the transmitter close to the target pipeline, and through electromagnetic induction, make the pipeline generate an induced current and emit electromagnetic signals;

[0021] The operator holds the receiver and slowly moves along the preliminarily judged pipeline alignment. The receiver displays the intensity of the received electromagnetic signal in real time. When the signal intensity is at the peak value, this position is the location of the underground pipeline;

[0022] When the signal intensity received by the receiver is 70% of the peak value, measure the vertical distance between the receiver and the ground at this time, and determine the vertical distance between the receiver and the ground at this time as the burial depth of the underground pipeline.

[0023] Preferably, the ground penetrating radar for detecting underground pipelines is used for non-metal pipelines. Obtaining the location and burial depth data of underground pipelines based on the ground penetrating radar includes:

[0024] Adopt a grid-shaped or S-shaped scanning path. In the ground penetrating radar image, the underground medium presents relatively uniform reflected signals, and its reflection form presents a hyperbolic characteristic, that is, this position is the location of the underground pipeline;

[0025] After determining the location of the underground pipeline, measure the two-way travel time t of the reflected signal c , and combine it with the known propagation speed v1 of the radar wave in the underground medium in this area. Calculate the buried depth h of the pipeline through the following formula:

[0026]

[0027] Among them, the propagation speed of the radar wave in different media is known, and the buried depth of the underground pipeline is determined by calculating the buried depth h of the pipeline.

[0028] Preferably, the acoustic wave detection obtains the reflected and scattered acoustic wave signals after propagating through the internal fluid of the underground pipeline, including:

[0029] Fix the acoustic wave generator and receiver on the pipeline. The acoustic wave generator selects the acoustic wave frequency and intensity according to the pipeline material and fluid type, and the acoustic wave receiver collects the reflected and scattered acoustic wave signals after propagating through the internal fluid of the pipeline;

[0030] The internal fluid state evaluation includes obstacle detection and flow velocity and flow rate evaluation. Among them, obstacle detection is to judge whether there are obstacles, bubbles or density inhomogeneous regions in the fluid according to the change of signal intensity. When the acoustic wave encounters an obstacle or a bubble, strong reflection and scattering will occur, resulting in a significant increase in the received signal intensity or abnormal fluctuations. Determine the position and size of the obstacle through the signal intensity change curve;

[0031] Among them, the flow velocity and flow rate evaluation is to install two pairs of acoustic wave generators and receivers at different positions upstream and downstream of the pipeline. By measuring the time difference of the acoustic wave propagating in the downstream and upstream directions, calculate the fluid flow velocity v2 according to the time difference and the acoustic wave propagation path length:

[0032]

[0033] Among them, L is the acoustic wave propagation path length, t1 is the acoustic wave propagation time in the downstream direction, and t2 is the acoustic wave propagation time in the upstream direction;

[0034] The flow rate is calculated according to the fluid flow velocity v2 and the pipeline cross-section, and is expressed as:

[0035] Q = v2 × A

[0036] Among them, Q is the fluid flow rate and A is the pipeline cross-section.

[0037] Preferably, the fusion of the detection data to generate the underground pipeline space model includes:

[0038] Fuse the data information obtained by the electromagnetic method, ground penetrating radar and acoustic wave detection, preprocess the data information obtained by the electromagnetic method, ground penetrating radar and acoustic wave detection, and obtain data information in a unified format;

[0039] Perform spatial position matching. Based on the horizontal position and burial depth of the underground pipeline, associate the pipeline position information determined by the electromagnetic method and ground penetrating radar with the fluid state information obtained by acoustic wave detection, so that the data information representing the same pipeline position in different data sources can be correctly matched;

[0040] Use weighted average to fuse the burial depth data at the same position obtained by different detection methods. The fused burial depth h is represented by the following formula fused :

[0041] h fused =ω EM h EM +ω GPR h GPR

[0042] where h EM is the burial depth obtained by the electromagnetic method, ω EM is its weight, h GPR is the burial depth obtained by the ground penetrating radar, and ω GPR is its weight;

[0043] Construct a three-dimensional underground pipeline space model according to the horizontal position, burial depth and information parameters of the underground pipeline through three-dimensional modeling software.

[0044] According to the second aspect of the present disclosure, a data acquisition system for underground pipeline detection is proposed, which is applied to the first aspect and includes:

[0045] A data collection module for collecting the drawing materials of the underground pipelines in the target area and extracting the information parameters of the material, pipeline and fluid type transported by the underground pipelines from the collected drawing materials;

[0046] A field exploration assistance module for assisting the staff to mark the position of the ground outcrop points of the underground pipelines during field exploration, record their coordinate information, and preliminarily judge the trend of the underground pipelines in combination with the collected drawing materials;

[0047] A detection execution module for detecting metal pipelines by the electromagnetic method to determine the horizontal position and burial depth of the underground pipelines, detecting non-metal pipelines by the ground penetrating radar to determine their pipeline positions and burial depths, and evaluating the internal fluid state of the underground pipelines by acoustic wave detection;

[0048] A data fusion module, which is used to uniformly convert different formats of data obtained by the detection execution module, perform preprocessing operations on different detection data, and through spatial position matching, associate and integrate the obtained pipeline position information and fluid state information, and use weighted average to fuse different detection data at the same position to obtain the fused underground pipeline detection data;

[0049] A model generation module, which is used to construct an underground pipeline spatial model in a three-dimensional space according to the fused underground pipeline detection data and the collected information parameters.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] 1. By comprehensively using electromagnetic method, ground penetrating radar and acoustic wave detection technology, the present invention can comprehensively collect the position, burial depth and internal fluid state information of underground pipelines, not only determine the physical position of the pipelines, but also evaluate the state of the internal fluid of the pipelines, providing more detailed data support for the maintenance and management of the pipelines.

[0052] 2. By fusing the data obtained from different detection technologies, the present invention can reduce the errors that may be brought by a single detection method, improve the accuracy and reliability of the data, and use the weighted average method to fuse different detection data at the same position, further enhancing the accuracy of the data.

[0053] 3. The underground pipeline detection data acquisition method provided by the present invention can adapt to pipelines of different materials and complex underground environments, can effectively perform detection and data acquisition, and its systematic process reduces manual intervention and repetitive labor, improves work efficiency, and shortens the time for data acquisition and processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 is a flowchart of the underground pipeline detection data acquisition method of the present invention;

[0055] Figure 2 is a block diagram of the underground pipeline detection data acquisition system of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0056] The following further describes in detail the embodiments of the present invention in conjunction with the drawings and embodiments. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0057] As shown in the attached Figure 1 figure:

[0058] Embodiment 1: The present invention provides an underground pipeline detection data acquisition method, including the following steps:

[0059] S1. Collect the drawings and data of underground pipelines in the target area and determine the information parameters of underground pipelines; the information parameters of underground pipelines include the material of the pipelines, the size of the pipe diameter and the type of fluid transported. The materials of the pipelines include metal pipelines and non-metal pipelines. The drawings and data include completion drawings, planning drawings and past detection reports.

[0060] By collecting the above materials, the staff can understand the general layout, key parameters and historical conditions of the pipeline in advance, greatly reducing the blindness in the detection process and significantly improving the detection efficiency. For example, if the drawings show that there is a large-diameter metal water supply pipeline in a certain area, the appropriate electromagnetic detection equipment and parameters can be selected in a targeted manner during the detection.

[0061] S2. Conduct field surveys, mark the ground outcrops of underground pipelines, and preliminarily determine the direction of the pipelines. The ground outcrops of underground pipelines include valve wells, inspection wells, fire hydrants, and pipeline vents. Use marking paint to mark their locations on the ground, and use a GPS locator to record accurate coordinates. Preliminary judgment of the direction of the pipelines is made based on the distribution of the ground outcrops and the collected underground pipeline drawings. Ground markings, i.e. pipeline direction signs, are used to assist in determining the direction of the pipelines. By marking the locations of the outcrops and recording the coordinates, the direction of the pipelines can be preliminarily determined based on the distribution of the outcrops and the information on the drawings.

[0062] By closely combining the actual location with the drawing information, accurate outcrop point marking provides a precise starting point and reliable reference position for subsequent detection, which helps to verify the accuracy of the drawing information. The initial judgment of the pipeline direction provides direction guidance for subsequent detection path planning, making the detection work more targeted and reducing unnecessary detection paths.

[0063] S3. Detect underground pipelines by electromagnetic method or ground penetrating radar to determine the location and buried depth of underground pipelines;

[0064] Among them, the electromagnetic method is used to detect underground pipelines for metal pipelines. The transmitter is placed close to the target pipeline, and the pipeline generates an induced current through electromagnetic induction, emitting electromagnetic signals.

[0065] The operator holds the receiver and moves slowly along the initially determined pipeline direction. The receiver displays the received electromagnetic signal strength in real time. When the signal strength reaches the peak, the location is the location of the underground pipeline.

[0066] When the signal strength received by the receiver is 70% of the peak value, measure the vertical distance between the receiver and the ground at this time. This distance is the buried depth of the underground pipeline.

[0067] Among them, ground penetrating radar is used to detect underground pipelines for non-metallic pipelines, adopting a grid-shaped or "S" - shaped scanning path. In the ground penetrating radar image, the underground medium presents relatively uniform reflection signals, and its reflection form presents a hyperbolic characteristic, that is, this position is the position of the underground pipeline.

[0068] After determining the position of the underground pipeline, by measuring the two-way travel time t of the reflection signal c , and combining with the known propagation speed v1 of the radar wave in the underground medium in this area, the pipeline burial depth h is calculated by the following formula:

[0069]

[0070] Among them, the propagation speed of the radar wave in different media is known, and the burial depth of the underground pipeline is determined by calculating the pipeline burial depth h.

[0071] By receiving the radar wave reflected by the underground medium to generate an image, the non-metallic pipeline and the pipeline in complex areas can be effectively detected. The pipeline position is accurately identified through the image characteristics and the burial depth is calculated, comprehensively mastering the distribution of underground pipelines, filling the blank of non-metallic pipeline detection.

[0072] S4. Collect the reflected and scattered acoustic wave signals after propagating through the internal fluid of the underground pipeline by acoustic wave detection to evaluate the internal fluid state; Acoustic wave detection is achieved by fixedly installing an acoustic wave generator and a receiver on the pipeline. Among them, the acoustic wave generator selects the acoustic wave frequency and intensity according to the pipeline material and fluid type, and the acoustic wave receiver collects the reflected and scattered acoustic wave signals after propagating through the internal fluid of the pipeline.

[0073] The evaluation of the internal fluid state includes obstacle detection and flow velocity and flow rate evaluation. Among them, obstacle detection is to judge whether there are obstacles, bubbles or regions with uneven density in the fluid according to the change of signal intensity. When the acoustic wave encounters an obstacle or a bubble, strong reflection and scattering will occur, resulting in a significant increase in the received signal intensity or abnormal fluctuations. The position and size of the obstacle are determined through the signal intensity change curve.

[0074] Among them, the flow velocity and flow rate evaluation is to install two pairs of acoustic wave generators and receivers at different positions upstream and downstream of the pipeline. By measuring the time difference of the acoustic wave propagating in the downstream and upstream directions, the fluid flow velocity v2 is calculated according to the time difference and the acoustic wave propagation path length:

[0075]

[0076] Among them, L is the acoustic wave propagation path length, t1 is the acoustic wave propagation time in the downstream direction, and t2 is the acoustic wave propagation time in the upstream direction;

[0077] The flow rate is calculated according to the fluid flow velocity v2 and the pipeline cross-section, expressed as:

[0078] Q = v2×A

[0079] Wherein, Q is the fluid flow rate and A is the cross-sectional area of the pipeline.

[0080] By detecting and collecting the reflected and scattered acoustic wave signals after propagating through the fluid inside the underground pipeline by acoustic wave detection, obstacles and bubbles in the fluid can be detected, the flow velocity and flow rate can be accurately calculated, etc., providing key data support for evaluating the fluid state in the underground pipeline. In the detection of oil pipelines, problems such as scaling and blockage in the pipeline can be detected in a timely manner to ensure the safe operation of the pipeline.

[0081] S5. Integrate different detection data to generate a spatial model of the underground pipeline. The integration of different detection data is to integrate the data information obtained by the electromagnetic method, ground penetrating radar and acoustic wave detection. First, preprocess the three data information to obtain data information in a unified format, and then perform spatial position matching. Based on the planar position and burial depth of the underground pipeline, associate the pipeline position information determined by the electromagnetic method and ground penetrating radar with the fluid state information obtained by acoustic wave detection, so that the data information representing the same pipeline position in different data sources can be correctly matched;

[0082] The weighted average is used to integrate the burial depth data obtained by different detection methods at the same position. The integrated burial depth h is represented by the following formula fused :

[0083] h fused = ω EM h EM + ω GPR h GPR

[0084] Wherein, h EM is the burial depth obtained by the electromagnetic method, ω EM is its weight, h GPR is the burial depth obtained by the ground penetrating radar, and ω GPR is its weight;

[0085] According to the planar position, burial depth and information parameters of the underground pipeline, a three-dimensional spatial model of the underground pipeline is constructed by using three-dimensional modeling software. The abstract data is converted into an intuitive three-dimensional model, which is convenient for users to intuitively understand various attributes such as the spatial distribution, material, pipe diameter, and fluid state of the underground pipeline, enabling users to deeply query the detailed information of specific pipelines and comprehensively master the situation of the underground pipeline.

[0086] As can be seen from the above, the drawing information collected in step S1 provides the basis for the on-site investigation in step S2, and the outcrop points marked and the estimated trend in step S2 guide the electromagnetic method and ground penetrating radar in step S3. The pipeline position and burial depth data determined in step S3, as well as the internal fluid state data evaluated in step S4, jointly serve as the basis for data fusion and model generation in step S5. Moreover, step S5 also constructs and generates a model based on the underground pipeline information parameters collected in step S1, realizing a complete process from basic information collection, on-site investigation, pipeline detection, fluid state evaluation to the final three-dimensional model construction and display, and comprehensively and accurately obtaining various types of information of underground pipelines.

[0087] Embodiment 2: As shown in the appendix Figure 2 The present invention also provides an underground pipeline detection data acquisition system, including:

[0088] A data collection module, configured to collect drawing materials of underground pipelines in a target area, and extract information parameters of the materials of the underground pipelines, the types of pipelines and the transported fluids from the collected drawing materials;

[0089] An on-site investigation assistance module, configured to assist workers in marking the positions of the ground outcrop points of the underground pipelines during on-site investigation, record their coordinate information, and preliminarily judge the trend of the underground pipelines in combination with the collected drawing materials;

[0090] A detection execution module, configured to detect metal pipelines by the electromagnetic method to determine the planar position and burial depth of the underground pipelines, detect non-metal pipelines by ground penetrating radar to determine their pipeline positions and burial depths, and evaluate the internal fluid state of the underground pipelines by acoustic wave detection;

[0091] A data fusion module, configured to uniformly convert different formats of data obtained by the detection execution module, perform preprocessing operations on different detection data, and through spatial position matching, associate and integrate the obtained pipeline position information and fluid state information, and use weighted average to fuse different detection data at the same position to obtain the fused underground pipeline detection data;

[0092] A model generation module, configured to construct an underground pipeline space model in a three-dimensional space according to the fused underground pipeline detection data and the collected information parameters.

[0093] Importantly, it should be noted that the construction and arrangement of the present application shown in multiple different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who refer to this disclosure should easily understand that many modifications are possible without substantially departing from the novel teachings and advantages of the subject matter described in this application. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the exemplary embodiments without departing from the scope of the present invention. Therefore, the present invention is not limited to a specific embodiment, but extends to various modifications that still fall within the scope of the appended claims.

[0094] In addition, to provide a concise description of the exemplary embodiments, all features of the actual embodiments may not be described (i.e., those features that are not relevant to the currently considered best mode of implementing the present invention or those features that are not relevant to implementing the present invention).

[0095] It should be understood that in the development of any actual implementation, in any engineering or design project, a large number of specific implementation decisions may be made. Such development efforts may be complex and time-consuming, but for those of ordinary skill in the art who benefit from this disclosure, without undue experimentation, such development efforts will be a routine task of design, manufacture, and production.

[0096] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A method for collecting underground pipeline detection data, characterized in that: The following steps are involved: S1. Determine the information parameters of underground pipelines based on the underground pipeline drawings and data in the target area; S2, obtaining pipeline direction data; The pipeline direction data is obtained by marking the ground outcropping points of the underground pipeline based on field survey; S3. Obtaining the location and burial depth data of underground pipelines; the location and burial depth data are obtained based on electromagnetic method or ground penetrating radar; S4, obtaining reflected and scattered sound wave signals after propagation through the internal fluid of the underground pipeline, and evaluating the internal fluid state, wherein the reflected and scattered sound wave signals are obtained based on sound wave detection; S5. Fusion of the detection data to generate an underground pipeline space model.

2. The underground pipeline detection data collection method according to claim 1, characterized in that: The information parameters of the underground pipeline include the material of the pipeline, the size of the pipe diameter and the type of fluid transported. The material of the pipeline includes metal pipeline and non-metal pipeline.

3. The underground pipeline detection data collection method according to claim 1, characterized in that: The ground outcropping points of the underground pipelines include valve wells, inspection wells, fire hydrants and pipeline vents. Use marking paint to mark the location of the underground pipeline on the ground, and use a GPS locator to record the accurate coordinates, and obtain the preliminary pipeline direction based on the distribution of ground outcropping points combined with the collected underground pipeline drawings; The obtaining of pipeline direction data further includes: Based on the ground markings, assist in determining the direction of the pipeline.

4. The underground pipeline detection data collection method according to claim 1, characterized in that: The electromagnetic method for detecting underground pipelines is used for metal pipelines, and the location and buried depth data of underground pipelines are obtained based on the electromagnetic method, including: Place the transmitter close to the target pipeline, generate an induced current in the pipeline through electromagnetic induction, and emit an electromagnetic signal; The operator holds the receiver and moves slowly along the initially determined pipeline direction. The receiver displays the received electromagnetic signal strength in real time. When the signal strength reaches the peak, the location is the location of the underground pipeline. When the signal strength received by the receiver is 70% of the peak value, the vertical distance between the receiver and the ground is measured, and the vertical distance between the receiver and the ground is determined as the buried depth of the underground pipeline.

5. The underground pipeline detection data collection method according to claim 1, characterized in that: The ground penetrating radar is used to detect underground pipelines for non-metallic pipelines, and the location and buried depth data of the underground pipelines are obtained based on the ground penetrating radar, including: Using a grid-shaped or S-shaped scanning path, in the ground penetrating radar image, the underground medium presents a relatively uniform reflection signal, and its reflection morphology presents a hyperbolic feature, which means that the location is the location of the underground pipeline; After the location of the underground pipeline is determined, the round-trip travel time t of the reflected signal is measured. c , and combined with the known radar wave propagation speed v1 in the underground medium of the area, the pipeline burial depth h is calculated by the following formula: Among them, the propagation speed of radar waves in different media is known, and the buried depth of the underground pipeline is determined by calculating the buried depth h of the pipeline.

6. The underground pipeline detection data collection method according to claim 1, characterized in that: The acoustic wave detection obtains reflected and scattered acoustic wave signals after propagating through the fluid inside the underground pipeline, including: By fixing the sound wave generator and receiver on the pipeline, the sound wave generator selects the sound wave frequency and intensity according to the pipeline material and fluid type, and the sound wave receiver collects the reflected and scattered sound wave signals after propagating through the fluid inside the pipeline; The internal fluid state assessment includes obstacle detection and flow rate and flow assessment, wherein obstacle detection is to judge whether there are obstacles, bubbles or areas of uneven density in the fluid based on changes in signal strength. When sound waves encounter obstacles or bubbles, strong reflection and scattering will occur, resulting in a significant increase in the received signal strength or abnormal fluctuations. The position and size of the obstacle are determined through the signal strength change curve; The flow rate and flow assessment is to install two pairs of sound wave generators and receivers at different locations in the upstream and downstream of the pipeline, measure the time difference of the sound wave propagation in the downstream and upstream directions, and calculate the fluid flow rate v2 based on the time difference and the length of the sound wave propagation path: Where L is the length of the sound wave propagation path, t1 is the propagation time of the sound wave in the downstream direction, and t2 is the propagation time of the sound wave in the upstream direction; The flow rate is calculated based on the fluid velocity v2 and the pipeline cross section and is expressed as: Q=v2×A Where Q is the fluid flow rate and A is the pipeline cross section.

7. The underground pipeline detection data collection method according to claim 1, characterized in that: The fusing of the detection data to generate an underground pipeline space model includes: The data information obtained by the electromagnetic method, ground penetrating radar and acoustic wave detection are integrated, and the data information obtained by the electromagnetic method, ground penetrating radar and acoustic wave detection are preprocessed to obtain data information in a unified format; Perform spatial position matching, using the plane position and burial depth of underground pipelines as the matching basis, and associate the pipeline position information determined by electromagnetic method and ground penetrating radar with the fluid state information obtained by acoustic wave detection, so that the data information representing the same pipeline position in different data sources can be correctly matched; The weighted average is used to fuse the burial depth data of the same location obtained by different detection methods. The fused burial depth h is expressed by the following formula: fused : h fused =ω EM h EM +ω GPR h GPR Among them, h EM is the buried depth obtained by electromagnetic method, ω EM Its weight, h GPR is the burial depth obtained by ground penetrating radar, ω GPR for its weight; A three-dimensional underground pipeline space model is constructed through three-dimensional modeling software based on the plane position, burial depth and information parameters of the underground pipeline.

8. An underground pipeline detection data acquisition system, characterized in that: include: A data collection module is used to collect drawings and data of underground pipelines in the target area, and extract information parameters of the material, pipeline and type of transported fluid of the underground pipelines from the collected drawings and data; The field survey auxiliary module is used to assist the staff in marking the location of the ground outcropping points of underground pipelines during field surveys, and record their coordinate information, and preliminarily determine the direction of underground pipelines in combination with the collected drawings and materials; The detection execution module is used to detect metal pipelines through electromagnetic methods to determine the plane position and burial depth of underground pipelines, detect non-metallic pipelines through ground penetrating radar to determine their pipeline positions and burial depths, and evaluate the internal fluid state of underground pipelines through acoustic wave detection; The data fusion module is used to uniformly convert the data of different formats obtained by the detection execution module, perform preprocessing operations on different detection data, and associate and integrate the obtained pipeline location information with the fluid state information through spatial position matching, and use weighted average to fuse different detection data at the same position to obtain fused underground pipeline detection data; The model generation module is used to construct an underground pipeline space model in three-dimensional space based on the fused underground pipeline detection data and the collected information parameters.

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