Concrete foundation pile visual information integration system and method based on 3D GIS and ultrasonic tomography fusion

Abstract

The invention discloses a concrete foundation pile visual information integration system and method based on 3D GIS and ultrasonic tomography fusion, the 3D GIS and ultrasonic tomography technology are fused, internal defects of a foundation pile are accurately positioned and visually presented, and the detection intuition and accuracy are remarkably improved. By constructing a three-dimensional information model, correlation analysis of foundation pile defects, structures and geologic body information is achieved, and engineers are assisted in comprehensively evaluating structural safety and risk levels. The system adopts an optimization algorithm and a multi-level framework, not only improves data processing efficiency, but also supports multi-dimensional interaction analysis, provides a scientific basis for operation and maintenance management and reinforcement design of the foundation pile, and effectively overcomes the defects that a traditional detection means is difficult to position, depends on experience and lacks unified management.

Description

Technical Field

[0001] The present invention relates to the technical field of in-situ testing, and in particular to a concrete foundation pile visualization information integration system and method based on the fusion of 3DGIS and ultrasonic tomography. Background Art

[0002] In recent years, with the continued advancement of infrastructure construction in my country, pile foundation integrity testing technology has become increasingly widely used in construction projects. As the critical load-bearing foundation of building structures, the quality of pile construction directly impacts the safety and stability of the project. Therefore, accurate and efficient pile foundation testing methods are crucial for ensuring project quality.

[0003] Currently, commonly used pile foundation inspection methods in engineering include the low-strain reflection wave method, the acoustic transmission method, and the core drilling method. The low-strain reflection wave method primarily assesses integrity by measuring the vibration response at the top of the pile. This qualitative analysis method struggles to accurately locate and quantify defects within the pile shaft. While the core drilling method can visually reveal the internal structure of the pile, as a destructive method, it is not only costly but also potentially detrimental to the pile quality. The acoustic transmission method, with its non-destructive nature and wide applicability, has become an important method for internal pile quality inspection. It utilizes the propagation characteristics of ultrasonic waves in concrete to identify defects within the pile foundation. However, in actual engineering applications, the acoustic transmission method typically only provides velocity-depth and amplitude-depth curves. The precise location, shape, and size of defects within concrete piles often rely on the tester's experience, which is significantly affected by human factors, making it difficult to ensure the accuracy and universality of the test results.

[0004] In recent years, with the development of computer science, ultrasonic tomography technology has developed accordingly. This technology has been applied to the field of concrete structure inspection to a certain extent. However, it still faces many challenges in the non-destructive testing of concrete foundation piles based on the acoustic transmission method, mainly in the following three aspects:

[0005] ① The vertical dimension of the pile section area between the two acoustic detection tubes is much larger than the horizontal dimension, which limits the applicability of traditional imaging methods and affects the imaging accuracy;

[0006] ② Due to the constraints of the detection space (inside the acoustic testing tube) and the conditions of the detection equipment, in the actual testing process, the vertical spacing between adjacent transmitting and receiving transducers is usually large, making it difficult to achieve a fine arrangement of elastic wave rays, thus putting higher requirements on ray path tracing.

[0007] ③The structure usually contains multiple concrete foundation piles to be tested. The quality of different foundation piles varies, and there is a lack of an effective means to uniformly and intuitively reflect the quality status of each foundation pile.

[0008] Therefore, in order to solve the above problems, it is urgent to propose a concrete foundation pile visualization information integration system based on the fusion of 3DGIS (three-dimensional geographic information system) and ultrasonic tomography, so as to comprehensively improve the accuracy and management efficiency of ultrasonic tomography detection of foundation piles in structures. Summary of the Invention

[0009] To solve the technical problems in the above background, the present invention provides a concrete pile visualization information integration system based on the fusion of 3DGIS and ultrasonic tomography, comprising: an acquisition module, a construction module, a calculation module, a comparison module, an allocation module, an update module and an identification module;

[0010] The acquisition module is used to collect travel time data for the concrete foundation pile to be tested using an ultrasonic transmission detection method to obtain the geometric dimensions of the concrete foundation pile and site geological information. The ultrasonic transmission detection method includes arranging an ultrasonic transducer in the acoustic detection tube of the foundation pile to excite and receive ultrasonic signals;

[0011] The construction module is used to construct a three-dimensional pile-geological body structure information model based on the geometric dimensions of the concrete piles and the site geological information;

[0012] The calculation module is used to construct a relationship matrix containing information of each wave source point and its adjacent source points based on the three-dimensional pile-geological body structure information model using the Dijkstra algorithm, and calculate the theoretical travel time data between all transducer pairs;

[0013] The comparison module is used to compare the on-site measured transducer pair travel time data collected by the acquisition module with the theoretical travel time data calculated by the calculation module, and record the theoretical calculated travel time error of the ultrasonic wave propagating between each transducer pair;

[0014] The allocation module is used to allocate the theoretical calculated travel time error obtained in the comparison module to the wave source point field in the three-dimensional pile foundation-geological body structure information model using the optimized SIRT inversion algorithm, and update the slowness value of each wave source point in the concrete pile foundation model;

[0015] The update module is used to repeat the workflow of the calculation module, the comparison module and the allocation module to iteratively update the three-dimensional pile-geological body structure information model so that the error between the theoretically calculated travel time data and the field measured data converges to a preset range, thereby obtaining a wave velocity distribution model that conforms to the actual concrete structure state;

[0016] The identification module is used to identify and analyze defects inside the concrete foundation pile based on the wave velocity distribution model, and determine the location, shape and range of the defects.

[0017] Preferably, the acquisition module uses the ultrasonic transmission detection method to collect travel time data, specifically: arranging ultrasonic transducers at preset intervals in the acoustic detection tube of the foundation pile, exciting ultrasonic signals, and receiving the ultrasonic signals through the receiving transducer, and recording the travel time data of the ultrasonic signals.

[0018] Preferably, the method for constructing a three-dimensional pile foundation-geological body structural information model by the construction module includes: obtaining geometric dimension parameters of the concrete pile foundation, including the length, width, height of the pile foundation and the layout position of the acoustic detection tube; collecting site geological information, including the distribution of geological layers and rock and soil property parameters; based on the geometric dimension parameters and geological information, using 3DGIS to construct the three-dimensional pile foundation-geological body structural information model.

[0019] Preferably, the workflow of the calculation module includes: constructing cubic grid units in the three-dimensional detection domain, and using the vertices of the grid units as wave source points; determining the spatial relationship between each wave source point and the surrounding adjacent wave source points, and constructing a relationship matrix of adjacent wave source points; and calculating the propagation time of ultrasonic waves between adjacent wave source points based on the distance and slowness between the wave source points.

[0020] Preferably, the workflow of the comparison module includes: for each transducer pair, calculating the difference between the field measured travel time data and the theoretical travel time data to obtain the travel time error; and statistically analyzing and recording the travel time errors of all transducer pairs to form an error data set.

[0021] Preferably, the workflow of the allocation module includes: initializing the medium slowness information in the field; correcting the wave source point slowness information based on the difference between the measured data and the calculated travel time combined with the relaxation factor; and updating the slowness information of all wave source points in the detection area using the nearest neighbor interpolation function method.

[0022] Preferably, the workflow of the update module includes: setting the number of iterations and the convergence threshold; in each iteration process, recalculating the theoretical travel time data, comparing it with the field measured data, and updating the wave source point slowness information; judging whether the error converges to a preset range, if so, stopping the iteration; if not, continuing the iterative update.

[0023] Preferably, the workflow of the identification module includes: visualizing the wave velocity distribution model to generate a three-dimensional visualization image; determining the location, shape and range of the defect by analyzing the abnormal area of ​​wave velocity in the three-dimensional visualization image; and evaluating the structural safety and integrity of the concrete foundation pile based on the location, shape and range of the defect.

[0024] The present invention also provides a method for integrating visualization information of concrete foundation piles based on the fusion of 3DGIS and ultrasonic tomography. The method is applied to the above-mentioned system and includes:

[0025] Step S1: For the concrete foundation pile to be tested, travel time data is collected using an ultrasonic transmission detection method to obtain the geometric dimensions of the concrete foundation pile and site geological information. The ultrasonic transmission detection method includes arranging an ultrasonic transducer in an acoustic detection tube of the foundation pile to excite and receive ultrasonic signals;

[0026] Step S2: constructing a three-dimensional pile-geological structure information model based on the geometric dimensions of the concrete piles and the site geological information;

[0027] Step S3: Based on the three-dimensional pile-geological body structure information model, a Dijkstra algorithm is used to construct a relationship matrix containing information of each wave source point and its adjacent source points, and the theoretical travel time data between all transducer pairs are calculated;

[0028] Step S4: comparing the on-site measured transducer pair travel time data collected in step S1 with the theoretical travel time data calculated in step S3, and recording the theoretical calculated travel time error of the ultrasonic wave propagating between each transducer pair;

[0029] Step S5: using the optimized SIRT inversion algorithm to distribute the error information obtained in step S4 to the wave source point field in the three-dimensional pile foundation-geological body structure information model, and updating the slowness value of each wave source point in the concrete pile foundation model;

[0030] Step S6: Repeat steps S3 to S5 to iteratively update the three-dimensional pile-geological body structure information model so that the error between the theoretically calculated travel time data and the field measured data converges to a preset range, thereby obtaining a wave velocity distribution model that conforms to the actual concrete structure state;

[0031] Step S7: Based on the wave velocity distribution model, identify and analyze defects inside the concrete foundation piles to determine the location, shape and range of the defects.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) Accurate defect location and visualization: The ultrasonic tomography optimization algorithm is integrated with 3DGIS to achieve three-dimensional accurate positioning and visualization of internal defects in pile foundations. Based on multi-view interaction and slice analysis functions, defect feature extraction and multi-dimensional judgment of structural status can be performed, thereby improving the intuitiveness and comprehensiveness of detection.

[0034] (2) Auxiliary diagnosis and risk assessment: Relying on the intuitive and interactive features of the integrated three-dimensional model, engineers can obtain complete and accurate inspection information, and then identify defects, determine risk levels and evaluate the safety of the structure.

[0035] (3) Defect-Structure-Geological Body Correlation Analysis: By integrating test data, pile foundation structural models, and 3D geological information, the distribution patterns of internal defects in pile foundations can be revealed, supporting the analysis of the causes of engineering disasters. In addition, this information integration system can also provide a data basis for the subsequent operation and maintenance management and reinforcement design of pile foundations, improving the reliability of pile foundation structure safety assessments under complex geological conditions.

[0036] (4) Comprehensive evaluation of structural status: Based on multi-source information integration, the system can achieve a comprehensive evaluation of key performance indicators such as pile integrity, stability and bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 This is a schematic diagram of the arrangement of wave source points according to an embodiment of the present invention;

[0039] Figure 2 Schematic diagram of a propagation model of 26 adjacent wave source points according to an embodiment of the present invention;

[0040] Figure 3 This is a flow chart of an optimization algorithm for ultrasonic tomography of concrete foundation piles according to an embodiment of the present invention;

[0041] Figure 4 This is a design diagram of the detection information integration platform according to an embodiment of the present invention;

[0042] Figure 5 This is a diagram of the detection information integration system architecture according to an embodiment of the present invention;

[0043] Figure 6 This is a schematic diagram of an integrated three-dimensional information model of defect information-concrete pile structure-geological body according to an embodiment of the present invention;

[0044] Figure 7 Schematic diagram of the transducer arrangement according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] Before proceeding with the description, the technical terms used in the present invention are first introduced.

[0048] Transducer pair: a transmitting transducer (Transmitter) and a receiving transducer (Receiver) that work in pairs in ultrasonic testing. The transducer arrangement of the present invention is as follows: Figure 7 shown.

[0049] Example 1

[0050] This embodiment provides a concrete pile visualization information integration system based on the fusion of 3DGIS and ultrasonic tomography (hereinafter referred to as the detection information integration system), including: an acquisition module, a construction module, a calculation module, a comparison module, an allocation module, an update module and an identification module.

[0051] The following will describe in detail how the present invention solves technical problems in real life in conjunction with this embodiment.

[0052] First, the acquisition module uses the ultrasonic transmission detection method to collect travel time data for the concrete foundation pile to be tested, and obtain the geometric dimensions of the concrete foundation pile and the site geological information. The ultrasonic transmission detection method includes arranging an ultrasonic transducer in the acoustic detection tube of the foundation pile to excite and receive ultrasonic signals.

[0053] In this embodiment, the wave source points are arranged as follows: Figure 1 As shown, close-range photography and aerial photography were used to obtain topographic and geological data and construct a DEM and DOM three-dimensional topographic and geological database.

[0054] Specifically, a cubic grid of cells is constructed in the three-dimensional detection domain, with its vertices serving as wave sources and each node representing the medium parameters of the surrounding field (such as wave velocity and slowness). The propagation time is calculated by multiplying the distance between adjacent nodes by the slowness.

[0055] On the other hand, this embodiment encrypts the number of wave source points in the field in the following way. The long side size of the area to be measured is L a , the short side is L b , the transducer spacing is ΔL, then the vertical / horizontal size ratio α of the cross section of the area to be measured is l and vertical density coefficient β e It can be expressed as:

[0056] α l =L a / L b

[0057]

[0058] Where, is the rounding symbol, L acc is the calculation accuracy.

[0059] The number of grid node types in depth, horizontal and vertical directions within the field are:

[0060]

[0061] At the same time, the ultrasonic tomography and concrete foundation pile structure data are stored in the form of 3DGIS compatible point cloud data. The flowchart of the concrete foundation pile ultrasonic tomography optimization algorithm is as follows: Figure 3 shown.

[0062] Afterwards, the construction module is used to construct a three-dimensional pile-geological body structure information model based on the geometric dimensions of the concrete piles and the site geological information.

[0063] Unify the projection and spatial reference system to achieve spatial alignment of ultrasonic tomography data, concrete pile structure data, and 3D geological models. Furthermore, through multi-level of detail (LOD) technology, an integrated 3D information model integrating defect information, pile structure, and geological body features is constructed, such as Figure 6 shown.

[0064] like Figure 2 The figure shows the wave source point model and the propagation pattern of 26 spatially adjacent wave source points in this embodiment. This step can quickly locate the position of each discrete wave source point in the field (including the layout of each transmitting and receiving transducer), which can significantly improve the efficiency of subsequent complex path retrieval and forward and inversion.

[0065] The calculation module is based on the three-dimensional pile-geological structure information model and the Dijkstra algorithm is used to construct a relationship matrix containing the information of each wave source point and its adjacent source points, and the theoretical travel time data between all transducer pairs are calculated.

[0066] Specifically, the Dijkstra algorithm is used to track the shortest propagation path of the ultrasonic wave in the field. The expression is as follows:

[0067]

[0068] Where, l d is the distance between adjacent source points; S sp 、S np are the slowness values ​​of the field source medium at the wave source point and the adjacent nodes respectively.

[0069] The comparison module is used to compare the on-site measured transducer pair travel time data collected by the acquisition module with the theoretical travel time data calculated in the calculation module, and record the theoretical calculated travel time error of the ultrasonic wave propagating between each transducer pair.

[0070] The allocation module uses the optimized SIRT inversion algorithm to allocate the error information obtained by the comparison module to the wave source point field in the three-dimensional pile foundation-geological body structure information model, and updates the slowness value of each wave source point in the concrete pile foundation model.

[0071] When the measured acoustic transmission data and the ultrasonic propagation path obtained by the forward algorithm are both known, the following inversion steps are used to reconstruct the acoustic information in the field:

[0072] (1)s k represents the medium slowness information in the field at k iterations, Represents the local slowness information of the jth node, s 0 is the initial iteration parameter.

[0073] (2) Represents the travel time of the i-th ray, where a ij is the effective path length of node j on the i-th ray, which is half of the sum of the distances from the node to the adjacent front and rear wave source points.

[0074] (3) According to the difference between the measured data and the calculated travel time, the slowness information of the wave source point is corrected in combination with the relaxation factor μ (0 < μ < 1):

[0075]

[0076] Among them, μ is the relaxation factor, which is used to accelerate the convergence of the results.

[0077] Based on the non-zero slowness nodes in the field obtained by the calculation module in step 1, the nearest neighbor interpolation function method is used to update the slowness information of all wave source points in the detection area.

[0078] The update module is used to repeat the workflow of the calculation module, comparison module and allocation module, and iteratively update the three-dimensional pile-geological body structure information model, so that the error between the theoretically calculated travel time data and the field measured data converges to a preset range, and obtains a wave velocity distribution model that conforms to the actual concrete structure state.

[0079] The identification module is used to identify and analyze defects inside concrete foundation piles based on the wave velocity distribution model, and determine the location, shape and range of the defects.

[0080] like Figure 4 As shown, the detection system of this embodiment adopts C / S architecture, which is divided into perception layer, data layer, business logic layer and presentation layer to meet the multi-functional and multi-level data processing requirements; its system architecture is as follows Figure 5 shown.

[0081] Example 2

[0082] This embodiment also provides a method for integrating visualization information of concrete foundation piles based on the fusion of 3DGIS and ultrasonic tomography, comprising the following steps:

[0083] Step S1: For the concrete foundation pile to be tested, the ultrasonic transmission detection method is used to collect travel time data to obtain the geometric dimensions of the concrete foundation pile and the site geological information. The ultrasonic transmission detection method includes arranging an ultrasonic transducer in the acoustic detection tube of the foundation pile to excite and receive ultrasonic signals.

[0084] In this embodiment, the wave source points are arranged as follows: Figure 1 As shown in the figure, close-range photography and aerial photography are used to obtain topographic and geological data and construct DEM and DOM three-dimensional topographic and geological databases.

[0085] Specifically, a cubic grid of cells is constructed in the three-dimensional detection domain, with its vertices serving as wave sources and each node representing the medium parameters of the surrounding field (such as wave velocity and slowness). The propagation time is calculated by multiplying the distance between adjacent nodes by the slowness.

[0086] On the other hand, this embodiment encrypts the number of wave source points in the field in the following way. The long side size of the area to be measured is L a , the short side is L b , the transducer spacing is ΔL, then the vertical / horizontal size ratio α of the cross section of the area to be measured is l and vertical density coefficient β e It can be expressed as:

[0087] α l =L a / L b

[0088]

[0089] Where, is the rounding symbol, L acc is the calculation accuracy.

[0090] The number of grid node types in depth, horizontal and vertical directions within the field are:

[0091]

[0092] At the same time, the ultrasonic tomography and concrete foundation pile structure data are stored in the form of 3DGIS compatible point cloud data. The flowchart of the concrete foundation pile ultrasonic tomography optimization algorithm is as follows: Figure 3 shown.

[0093] Step S2: Construct a three-dimensional pile-geological structure information model based on the geometric dimensions of the concrete piles and the site geological information.

[0094] Unify the projection and spatial reference system to achieve spatial alignment of ultrasonic tomography data, concrete pile structure data, and 3D geological models. Furthermore, through multi-level of detail (LOD) technology, an integrated 3D information model integrating defect information, pile structure, and geological body features is constructed, such as Figure 6 shown.

[0095] like Figure 2 The figure shows the wave source point model and the propagation pattern of 26 spatially adjacent wave source points in this embodiment. This step can quickly locate the position of each discrete wave source point in the field (including the layout of each transmitting and receiving transducer), which can significantly improve the efficiency of subsequent complex path retrieval and forward and inversion.

[0096] Step S3: Based on the three-dimensional pile-geological body structure information model, the Dijkstra algorithm is used to construct a relationship matrix containing the information of each wave source point and its adjacent source points, and the theoretical travel time data between all transducer pairs are calculated.

[0097] Specifically, the Dijkstra algorithm is used to track the shortest propagation path of the ultrasonic wave in the field. The expression is as follows:

[0098]

[0099] Where, l d is the distance between adjacent source points; S sp 、S np are the slowness values ​​of the field source medium at the wave source point and the adjacent nodes respectively.

[0100] Step S4: Compare the on-site measured transducer pair travel time data collected in step S1 with the theoretical travel time data calculated in step S3, and record the theoretical calculated travel time error of the ultrasonic wave propagating between each transducer pair.

[0101] Step S5: using the optimized SIRT inversion algorithm to distribute the error information obtained in step S4 to the wave source point field in the three-dimensional pile foundation-geological body structure information model, and update the slowness value of each wave source point in the concrete pile foundation model.

[0102] When the measured acoustic wave transmission data and the corresponding ray propagation paths are known, the following inversion steps are used to reconstruct the acoustic information in the field:

[0103] (1)s k represents the medium slowness information in the field at k iterations, Represents the local slowness information of the jth node, s 0 is the initial iteration parameter.

[0104] (2) Represents the travel time of the i-th ray, where a ij is the effective path length of node j on the i-th ray, which is half of the sum of the distances from the node to the adjacent front and rear wave source points.

[0105] (3) According to the difference between the measured data and the calculated travel time, the slowness information of the wave source point is corrected in combination with the relaxation factor μ (0 < μ < 1):

[0106]

[0107] Among them, μ is the relaxation factor, which is used to accelerate the convergence of the results.

[0108] Based on the non-zero slowness nodes in the field obtained in step S3, the nearest neighbor interpolation function method is used to update the slowness information of all wave source points in the detection area.

[0109] Step S6: Repeat steps S3 to S5 to iteratively update the three-dimensional pile foundation-geological body structure information model so that the error between the theoretically calculated travel time data and the field measured data converges to a preset range, and obtain a wave velocity distribution model that conforms to the actual concrete structure state.

[0110] Step S7: Based on the wave velocity distribution model, identify and analyze defects inside the concrete foundation piles to determine the location, shape, and range of the defects.

[0111] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A concrete pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion, characterized by: include: Acquisition module, construction module, calculation module, comparison module, allocation module, update module and recognition module; The acquisition module is used to collect travel time data for the concrete foundation pile to be tested using an ultrasonic transmission detection method to obtain the geometric dimensions of the concrete foundation pile and site geological information. The ultrasonic transmission detection method includes arranging an ultrasonic transducer in the acoustic detection tube of the foundation pile to excite and receive ultrasonic signals; The construction module is used to construct a three-dimensional pile-geological body structure information model based on the geometric dimensions of the concrete piles and the site geological information; The calculation module is used to construct a relationship matrix containing information of each wave source point and its adjacent source points based on the three-dimensional pile-geological body structure information model using the Dijkstra algorithm, and calculate the theoretical travel time data between all transducer pairs; The comparison module is used to compare the transducer pair travel time data collected in the collection module with the theoretical travel time data calculated in the calculation module, and record the theoretical calculated travel time error of the ultrasonic wave propagating between each transducer pair; The allocation module is used to allocate the theoretical calculated travel time error obtained in the comparison module to the wave source point field of the three-dimensional pile foundation-geological body structure information model using the optimized SIRT inversion algorithm, and update the slowness value of each wave source point in the concrete pile foundation model; The update module is used to repeat the workflow of the calculation module, the comparison module and the allocation module to iteratively update the three-dimensional pile foundation-geological body structure information model so that the error between the calculated theoretical travel time data and the field measured data converges to a preset range, thereby obtaining a wave velocity distribution model that conforms to the actual concrete structure state; The identification module is used to identify and analyze defects inside the concrete foundation pile based on the wave velocity distribution model, and determine the location, shape and range of the defects.

2. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The acquisition module uses the ultrasonic transmission detection method to collect travel time data, specifically: arranging ultrasonic transducers at preset intervals in the acoustic detection tube of the foundation pile, exciting ultrasonic signals, and receiving the ultrasonic signals through the receiving transducer, and recording the travel time data of the ultrasonic signals.

3. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The method for constructing a three-dimensional pile foundation-geological body structural information model using the construction module includes: obtaining geometric dimension parameters of concrete pile foundations, including the length, width, height of the pile foundations and the layout position of the acoustic detection tube; collecting site geological information, including the distribution of geological layers and rock and soil property parameters; and constructing the three-dimensional pile foundation-geological body structural information model using 3DGIS based on the geometric dimension parameters and geological information.

4. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The workflow of the calculation module includes: constructing cubic grid units in the three-dimensional detection domain, and using the vertices of the grid units as wave source points; determining the spatial relationship between each wave source point and its surrounding adjacent wave source points, and constructing a relationship matrix of adjacent wave source points; and calculating the propagation time of ultrasonic waves between adjacent wave source points based on the distance and slowness between the wave source points.

5. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The workflow of the comparison module includes: for each transducer pair, calculating the difference between the field measured travel time data and the theoretical travel time data to obtain the travel time error; and statistically recording the travel time errors of all transducer pairs to form an error data set.

6. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The workflow of the allocation module includes: initializing the medium slowness information in the field; correcting the wave source point slowness information based on the difference between the measured data and the calculated travel time combined with the relaxation factor; and updating the slowness information of all wave source points in the detection area using the nearest neighbor interpolation function method.

7. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The workflow of the update module includes: setting the number of iterations and the convergence threshold; during each iteration, recalculating the theoretical travel time data, comparing it with the field measured data, and updating the wave source point slowness information; judging whether the error converges to a preset range, if so, stopping the iteration; if not, continuing the iterative update.

8. The concrete foundation pile visualization information integration system based on 3DGIS and ultrasonic tomography fusion according to claim 1 is characterized in that: The workflow of the identification module includes: visualizing the wave velocity distribution model to generate a three-dimensional visualization image; determining the location, shape, and range of defects by analyzing abnormal areas of wave velocity in the three-dimensional visualization image; and evaluating the structural safety and integrity of the concrete foundation piles based on the location, shape, and range of the defects.

9. A method for integrating visualization information of concrete foundation piles based on the fusion of 3DGIS and ultrasonic tomography, the method being applied to the system according to any one of claims 1 to 8, characterized in that: include: Step S1: For the concrete foundation pile to be tested, travel time data is collected using an ultrasonic transmission detection method to obtain the geometric dimensions of the concrete foundation pile and site geological information. The ultrasonic transmission detection method includes arranging an ultrasonic transducer in an acoustic detection tube of the foundation pile to excite and receive ultrasonic signals; Step S2: constructing a three-dimensional pile-geological structure information model based on the geometric dimensions of the concrete piles and the site geological information; Step S3: Based on the three-dimensional pile-geological body structure information model, a Dijkstra algorithm is used to construct a relationship matrix containing information of each wave source point and its adjacent source points, and the theoretical travel time data between all transducer pairs are calculated; Step S4: comparing the transducer pair travel time data collected in step S1 with the theoretical travel time data calculated in step S3, and recording the theoretical calculated travel time error of the ultrasonic wave propagating between each transducer pair; Step S5: using the optimized SIRT inversion algorithm to distribute the theoretical calculated travel time error obtained in step S4 to the wave source point field of the three-dimensional pile-geological structure information model, and updating the slowness value of each wave source point in the concrete pile model; Step S6: Repeat steps S3 to S5 to iteratively update the three-dimensional pile-geological body structure information model so that the error between the theoretically calculated travel time data and the field measured data converges to a preset range, thereby obtaining a wave velocity distribution model that conforms to the actual concrete structure state; Step S7: Based on the wave velocity distribution model, identify and analyze defects inside the concrete foundation piles to determine the location, shape and range of the defects.

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