Construction method and system for general structure analysis model of hydraulic structure under BIM (Building Information Modeling) framework

Abstract

The invention discloses a construction method of a general structure analysis model of a hydraulic structure under a BIM framework. The construction method comprises the following steps: extracting a BIM entity model by means of an IFC toolbox; preprocessing the complex hydraulic structure entity model by using advanced virtual topology operation, and then performing mesh generation; preprocessing the terrain surface in a certain range by using a grid smoothing method, and then performing grid subdivision; constructing a general structure analysis model of the hydraulic structure based on the BIM metadata model; and constructing a data interface intercommunicated with the structure analysis software. According to the construction method and system for the general structure analysis model of the hydraulic structure under the BIM framework, a complex hydraulic structure entity model and terrain surface preprocessing within a certain range are supported, and information expression and information interaction based on a general data model are supported; the advantages of BIM information integration can be brought into full play, the construction efficiency and precision of the structure analysis model are improved, and the construction capability of the hydraulic structure analysis model is further expanded under a BIM framework.

Description

Technical Field

[0001] The invention belongs to the field of hydraulic structure safety analysis, and specifically is a method for constructing a universal structural analysis model of a hydraulic structure under a BIM framework. Background Art

[0002] Building Information Model (BIM) is an integrated management environment that supports the entire life cycle of engineering projects. It not only includes data models that describe the three-dimensional geometric information of engineering objects and related engineering information, but also integrates behavioral models to simulate the behavior of buildings in the real world and provide timely and reliable support for management decisions. However, since geometric modeling and finite element analysis follow completely different principles, the three-dimensional solid models drawn by BIM design software usually cannot meet the analysis requirements and need to be edited and adjusted before meshing.

[0003] Therefore, in order to reduce repetitive modeling work, give full play to the advantages of BIM information integration, and improve the efficiency and accuracy of structural analysis model construction, it is of great significance to further expand the ability to build hydraulic structure analysis models under the BIM framework.

[0004] At present, domestic and foreign scholars have done a lot of exploration and research on the automatic conversion method of structural analysis models based on existing building information models, but most of the research is carried out around building models and building structural analysis models. The research content mainly focuses on inferring the geometric topological information of line and surface units from the solid model information of building components such as beams, columns, and walls, and only supports the construction of structural analysis models based on line and surface units. At this stage, the research on structural analysis model conversion based on solid grid units is only applicable to some simple and regular solid models, and the information interaction and expression depend on specific application software, which has great limitations.

[0005] Considering that most hydraulic structures are complex solid structures, and the influence of terrain entities within a certain range on the main structure must be considered when conducting structural analysis, there are still many shortcomings in using existing research to convert the complex solid model of hydraulic structures into a structural analysis model based on solid grid units in the BIM environment.

[0006] In summary, it is necessary to fully study the above issues from two aspects: the conversion of hydraulic structure entity model to grid unit model and the information interaction and expression of structural analysis model. Summary of the invention

[0007] The purpose of the present invention is to provide a method for constructing a universal structural analysis model of hydraulic structures under the BIM framework in response to the problems existing in the prior art, which can realize the preprocessing of complex entity models of hydraulic structures and terrain surfaces within a certain range, as well as the information expression and information interaction of the universal structural analysis model.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] The present invention provides a method for constructing a universal structural analysis model of a hydraulic structure under a BIM framework, the method comprising the following steps:

[0010] Step S1: Use tools that support the IFC standard to extract the BIM entity model, screen the key components of the hydraulic structure, and export relevant geometric data to support the subsequent construction of the structural analysis model;

[0011] Step S2: Using advanced virtual topology operations, the topology of the complex hydraulic structure entity model is adjusted and edited without changing the geometric part of the model, and then meshing is performed;

[0012] Step S3: Based on the visual perception method, the visual saliency of the mesh vertices is calculated by local contrast and global sparsity, the terrain mesh features are distinguished, and the terrain mesh is smoothed by a hybrid low-pass filter, and then the smoothed terrain surface is meshed by an automatic meshing algorithm;

[0013] Step S4: Based on the BIM metadata model, construct a sub-model view of hydraulic structure analysis, extract and integrate structural analysis parameters, and generate a standardized general structural analysis data model;

[0014] Step S5: Construct a data interface for communication with the structural analysis software.

[0015] Furthermore, in step S1, the method for extracting the BIM entity model includes: adopting an IFC information direct access method based on a standard data access interface, using an IFC toolbox to screen the entity model of the main structure of the hydraulic structure, extracting key components including the dam body, gates, energy dissipation facilities and water inlets, and exporting the geometric data information of the entity model in STEP format or SAT format to ensure the adequacy and completeness of the model.

[0016] Further, step S2 includes the following steps:

[0017] Step S201: performing basic virtual topological operations, including fusion, segmentation, connection, and construction, and repeatedly performing these operations in a specific order to form advanced virtual topological operations, including removing through holes, removing grooves, and model decomposition;

[0018] Step S202: Identify small features that are attached to the main structure of the hydraulic structure but have little impact on the overall analysis results of the model and significantly increase the difficulty of model meshing, including corridors and holes in the concrete dam body and track grooves built into different gates;

[0019] Step S203: remove the above-mentioned fine geometric features through advanced virtual topology operations, and use an automatic meshing algorithm to mesh the main structure.

[0020] Further, step S3 includes the following steps:

[0021] Step S301: Calculate any given vertex v in the terrain grid by using local contrast and global sparsity, and K-means clustering algorithm i The local contrast S l (v i ) and the global sparsity S g (v i ), including the following sub-steps:

[0022] Step S301.1: Calculate the local contrast S using formula (1) l (v i ), the calculation formula is as follows:

[0023]

[0024] Where U i are the m faces closest to the vertex, that is, σ a Take it as 0.6; ri is the size of the height map (the Euclidean distance from itself to the mesh surface along the ray perpendicular to the cutting plane); Z ri represents the Zernike coefficient;

[0025] Step S301.2: Calculate the global sparsity S using formula (2) g (v i ), the calculation formula is as follows:

[0026]

[0027] In the formula, Represents all vertices in the mesh, vertices with the same features have the same sparsity;

[0028] Step S301.3: Perform cluster analysis on similar vertices using the K-means clustering algorithm, replace the vertices in formula (2) with the center points of the corresponding clusters, and derive the sparsity of the cluster using formula (3). The sparsity calculation formula for the cluster is as follows:

[0029]

[0030] In the formula, c i and c jThey represent the center points of cluster i and cluster j in the feature space, K is the total number of clusters after clustering, n is the number of vertices in the grid, and n j represents the number of vertices in cluster j;

[0031] Step S301.4: After evaluating the sparsity of each cluster sample, the sparsity of a single vertex is calculated by an appropriate interpolation method. For a given vertex v i , the global sparsity of the vertex is calculated by formula (4):

[0032]

[0033] Where, T i are the m clusters closest to the vertex; σ a The value is 0.3, which is closer to the vertex v in the feature space. i The cluster with larger weight is assigned;

[0034] Step S302: When the local contrast S l (v i ) and the global sparsity S g (v i ) are calculated respectively, the visual saliency of the mesh vertices is calculated by formula (5), and it is normalized by formula (6) as the feature scale to distinguish the size features. The calculation formula is as follows:

[0035] S(v i )=S l (v i )+λS g (v i ) (5)

[0037]

[0038] In the formula, λ represents the weight factor, S i To obtain the visual saliency of vertex i by considering both local contrast and global sparsity, S max is the most significant value among the mesh vertices, S min is the lowest significant value among the mesh vertices;

[0039] Step S303: Select an appropriate threshold according to the actual situation of the terrain surface, and set the vertices larger than the threshold as small-scale feature vertices (set the label variable ε i =1), and the vertices smaller than the threshold are set as large-scale feature vertices (set the label variable ε i =0);

[0040] Step S304: Use a mixed low-pass filter to perform terrain mesh smoothing, that is, use different cutoff frequencies at different terrain mesh vertices. i The cut-off frequency at can be determined by the following formula:

[0041] σ i =α(1-ε i )+βε i (7)

[0043] In the formula, σ i is the cutoff frequency at vertex i, α is the large-scale feature point (ε i =0) participates in the cutoff frequency of geometric reconstruction, β is the small-scale feature point (ε i =1) is the cutoff frequency for geometric reconstruction;

[0044] Step S305: using an automatic meshing algorithm to perform quadrilateral meshing on the smoothed terrain surface, thereby achieving the goal of generating terrain solid hexahedral units.

[0045] Furthermore, in step S3, the time complexity of calculating the saliency of all vertices is O(n 2 ), where n is the number of vertices in the grid. In order to reduce the computational complexity, the K-means clustering algorithm is used to adaptively sample different spaces by clustering the vertices into no more than 50 clusters. The number of clusters is significantly less than the actual number of vertices, thereby significantly reducing the computational complexity.

[0046] Further, step S4 includes the following steps:

[0047] Step S401: constructing a sub-model view definition for hydraulic structure analysis based on the BIM metadata model;

[0048] Step S402: extracting unit node information, physical and mechanical parameters, structural loads, boundary conditions and other related information from the grid model and the global BIM data model according to the specific information interaction requirements in the model view definition;

[0049] Step S403: Describe the necessary information required for the structural analysis model in a unified and standard form to form a universal data model that is independent of the expression language and the application software.

[0050] Furthermore, in step S5, the constructed data interface is used to implement the following three functions:

[0051] (1) Parse the general data model and read the key information required for structural analysis;

[0052] (2) Perform data information matching, integrating the geometric topological information of the grid cells obtained from the grid cell model with the material information of the main structure obtained from the global IFC model to ensure the consistency of information;

[0053] (3) Generate calculation files in a specific format according to the requirements of the structural analysis software.

[0054] Furthermore, the present invention adopts the following technical solutions:

[0055] A general structural analysis model construction system for hydraulic structures under a BIM framework, which is applied to the general structural analysis model construction method for hydraulic structures under a BIM framework as claimed in claims 1 to 7, and the general structural analysis model construction system for hydraulic structures under a BIM framework comprises:

[0056] The geometric model export module includes: a structural analysis unit, which is used to screen the structures that need to be analyzed in the main body of the hydraulic structure; a solid model export unit, which is used to select the file export format and add additional information;

[0057] The solid model preprocessing module includes: a model adjustment unit, which is used to select appropriate advanced virtual topology operations to process fine features on the solid model; a mesh automatic division unit, which is used to select appropriate automatic division algorithms according to the features of the solid model to perform mesh division on the processed solid model;

[0058] The terrain surface preprocessing module includes: a surface smoothing module, which is used to distinguish and filter small-scale features on the terrain surface, and only retain large-scale terrain features; a grid automatic subdivision unit, which is used to select a suitable algorithm to divide the surface unit and extend it in the vertical direction to form a terrain solid grid unit;

[0059] Mesh model analysis module: used to analyze the above-mentioned entity unit information that has been segmented, including the number of units, the number of nodes, the unit number, the node number, the node unit relationship, and the node coordinates;

[0060] The structural analysis model creation module includes: an information extraction unit, which is used to extract information from the grid model and material information and load information from the IFC model; a constraint application unit, which is used to batch select surface units or node units and add corresponding constraints; a general structural analysis model construction unit, which is used to import the pre-compiled sub-model view definition for hydraulic structure analysis and extract and integrate the necessary information in the model based on the sub-model view definition;

[0061] Data interface module: used to select the formats supported by different finite element commercial software, perform model analysis and information matching, and generate calculation files in a specific format.

[0062] Furthermore, the present invention adopts the following technical solutions:

[0063] An electronic device comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the method for constructing a general structural analysis model of a hydraulic structure under the BIM framework as described in any one of claims 1 to 7 can be implemented.

[0064] Furthermore, the present invention adopts the following technical solutions:

[0065] A computer-readable storage medium having a computer program stored thereon, wherein the computer program is used to run the method for constructing a general structural analysis model of a hydraulic structure under the BIM framework as described in any one of claims 1 to 7.

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] (1) The method for constructing a general structural analysis model of hydraulic structures under the BIM framework proposed in the present invention can quickly preprocess the complex entity model and the terrain surface according to the characteristics of the hydraulic structure entity model, so as to realize the automatic segmentation of the finite element grid.

[0068] (2) The present invention provides an information interaction and expression method suitable for hydraulic structure analysis models, which can support the entire process of constructing hydraulic structure analysis models under the BIM framework and help further improve the BIM-based structural analysis model conversion mechanism.

[0069] (3) The data interface provided by the present invention can parse the general structural analysis model and reintegrate the information format of the structural analysis model according to the specific structural analysis software selected by the user, which helps to generate a hydraulic structure analysis model acceptable to any structural analysis software from the IFC information model exported by any BIM design software. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 is a flow chart of an embodiment of the present invention.

[0071] FIG. 2( a ) and FIG. 2( b ) are respectively an original entity model and a simplified entity model after preprocessing of a gravity dam powerhouse section in an embodiment of the present invention.

[0072] Figure 3 It is a general structural analysis data model of a concrete dam plant section in an embodiment of the present invention.

[0073] FIG. 4( a ) and FIG. 4( b ) are respectively the original terrain surface and the terrain surface after smoothing preprocessing of a certain arch dam in an embodiment of the present invention. DETAILED DESCRIPTION

[0074] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solution of the present invention. 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 creative work are within the scope of protection of the present invention.

[0075] like Figure 1 As shown, this embodiment provides a method for constructing a general structural analysis model of a hydraulic structure under a BIM framework, comprising the following steps:

[0076] Step 1: Extract the BIM entity model with the help of the IFC toolbox. More specifically, the IFC toolbox supports the separation of geometric data and non-geometric data of engineering objects using only very concise codes, avoiding the transfer and storage of large amounts of data in the database. The IFC toolbox can also realize the conversion of the entity model described by the IFC standard into other data formats. For example, both the Xbim and IfcOpenShell toolboxes support the export of IFC geometry information into STEP and SAT formats.

[0077] Step 2: Use advanced virtual topology operations to preprocess the complex hydraulic structure entity model and then perform meshing. More specifically, advanced virtual topology operations such as removing through holes, removing grooves, and model decomposition are used to perform preprocessing operations on complex models to meet the input requirements of the meshing algorithm. This operation requires only a small amount of human intervention and is universal. It can avoid adjusting the geometric part of the original model and greatly simplify the model modification process.

[0078] Step 3: Use a grid smoothing method to pre-process the terrain surface within a certain range, and then perform grid division; more specifically, the method of the present invention can accurately identify small-scale features on the surface from the perspective of visual perception and accurately eliminate them, which is particularly suitable for reducing the computational complexity of large-scale terrain surface smoothing work.

[0079] More specifically, the specific steps for accurately identifying small-scale features on the surface using visual perception principles and hybrid filtering methods are as follows:

[0080] First, the terrain grid features are distinguished based on human visual perception. This method calculates the data significance of the grid model through the local contrast principle and the global sparse principle, and uses it as the basis for distinguishing the feature scale. i , first calculate the local contrast S l (v i ) and the global sparsity S g (v i ). For a given vertex v i, there are m closely adjacent patches, using To represent, then the vertex v i The local contrast at can be calculated using the following formula:

[0081]

[0082] In the formula, σ a Take it as 0.6. ri is the size of the height map (the Euclidean distance from itself to the mesh surface along a ray perpendicular to the cutting plane). ri represents the Zernike coefficient. In contrast to local contrast, global saliency emphasizes regions of the mesh rather than its boundaries. For a given vertex v i , its global significance can be defined as:

[0083]

[0084] In the formula, Represents all vertices in the mesh, vertices with the same features have the same saliency. The time complexity of calculating the saliency of all vertices is O(n 2 ), where n is the number of vertices in the grid. It can be seen that the computational cost is high even for medium-sized grids. Therefore, after clustering similar vertices, the vertices in formula (2) can be replaced with the center points of the corresponding clusters to derive the significance of the cluster. The formula for calculating the significance of the cluster is as follows:

[0085]

[0086] In the formula, c i and c j They represent the center points of cluster i and cluster j in the feature space, K is the total number of clusters after clustering, and n j represents the number of vertices in cluster j. After evaluating the significance of each cluster sample, the significance of a single vertex can be obtained by simple interpolation. For a given vertex v i , first we should find m clusters closest to the vertex in the feature space, assuming that T i Representing these clusters, the global sparsity of the vertices can be calculated by the following formula:

[0087]

[0088] In the formula, Here, σ a It can be taken as 0.3, which can be closer to the vertex v in the feature space iThe K-means clustering algorithm can adaptively sample different spaces. For general mesh models, good clustering results can be obtained within the range of 50 clusters. Clustering makes the number of clusters much smaller than the actual number of vertices, which greatly improves the computational complexity.

[0089] Next, when the local contrast S l (v i ) and the global sparsity S g (v i ) are calculated respectively, the visual saliency of the mesh vertices can be calculated by formula (5), and it can be normalized by formula (6) and used as the feature scale to distinguish the size features.

[0090] S(v i )=S l (v i )+λS g (v i ) (5)

[0091] In the formula, λ represents the weight factor.

[0092]

[0093] In the formula, S i To obtain the visual saliency of vertex i by considering both local contrast and global sparsity, S max is the most significant value among the mesh vertices, S min is the least significant value among the mesh vertices.

[0094] Then, according to the actual situation of the terrain surface, a suitable threshold is selected and the vertices larger than the threshold are set as small-scale feature vertices (the label variable ε is set as i =1), and the vertices smaller than the threshold are set as large-scale feature vertices (set the label variable ε i =0).

[0095] Finally, a hybrid low-pass filter is used to smooth the terrain mesh. This is manifested by using different cutoff frequencies at different terrain mesh vertices. The cutoff frequency at a vertex i can be determined by the following formula:

[0096] σ i =α(1-ε i )+βε i (7)

[0097] In the formula, σ i is the cutoff frequency at vertex i, α is the large-scale feature point (ε i =0) participates in the cutoff frequency of geometric reconstruction, β is the small-scale feature point (ε i=1) is the cutoff frequency for geometric reconstruction.

[0098] More specifically, the automatic segmentation of the processed solid mesh and terrain surface can be achieved by using the CUBIT toolbox, which integrates a variety of commonly used quadrilateral mesh automatic segmentation algorithms and hexahedral mesh automatic segmentation algorithms and is easy to integrate into the system.

[0099] Step 4: Construct a general structural analysis model for hydraulic structures based on the BIM metadata model. More specifically, constructing a sub-model view definition for hydraulic structure analysis based on the BIM metadata model can lay a foundation for accurately extracting information related to structural analysis; more specifically, describing the necessary information required for the structural analysis model in a unified and standard form (e.g., XML data model), which may include IFC model information, grid model information, and user input information.

[0100] Step 5: Construct a data interface that communicates with the structural analysis software. More specifically, the main implementation content of the interface includes the following three parts: 1) Parse the XML data model and read the necessary information for structural analysis. 2) Data information matching. In the present invention, there are multiple sources of information, and information from different sources must be matched to ensure the consistency of information. The present invention can extract the global unified identifier GUID of the structural entity as the basis for information matching. 3) According to the requirements of the finite element analysis software, a calculation file in a specific format is formed.

[0101] This embodiment also provides a general structural analysis model construction system for hydraulic structures under the BIM framework, including:

[0102] The geometric model export module includes: a structural analysis unit for screening the structures that need to be analyzed in the main body of the hydraulic structure; and a solid model export unit for selecting the file export format and adding additional information.

[0103] The solid model preprocessing module includes: a model adjustment unit for selecting appropriate advanced virtual topology operations to process fine features on the solid model; and a mesh automatic subdivision unit for selecting appropriate automatic subdivision algorithms according to the features of the solid model to perform mesh subdivision on the processed solid model.

[0104] The terrain surface preprocessing module includes: a surface smoothing module, which is used to distinguish and filter small-scale features on the terrain surface and retain only large-scale terrain features; a grid automatic subdivision unit, which is used to select a suitable algorithm to divide the surface unit and extend it vertically to form a terrain solid grid unit.

[0105] Mesh model analysis module: used to analyze the above-mentioned entity unit information that has been segmented, including the number of units, the number of nodes, the unit number, the node number, the node unit relationship, and the node coordinates.

[0106] The structural analysis model creation module includes: an information extraction unit, which is used to extract information from the grid model and material information and load information from the IFC model; a constraint application unit, which is used to batch select surface units or node units and add corresponding constraints; a general structural analysis model construction unit, which is used to import pre-compiled sub-model view definitions for hydraulic structure analysis, and extract and integrate necessary information in the model based on the sub-model view definitions.

[0107] Data interface module: used to select the formats supported by different finite element commercial software, perform model analysis and information matching, and generate calculation files in a specific format.

[0108] More specifically, the general structural analysis model construction system for hydraulic structures under the BIM framework also includes:

[0109] An electronic device includes a processor and a memory, wherein a computer program is stored in the memory. When the computer program is executed by the processor, the method for constructing a general structural analysis model of a hydraulic structure under the BIM framework as described above can be implemented.

[0110] A computer-readable storage medium stores a computer program, wherein the computer program is used to run the method for constructing a general structural analysis model of a hydraulic structure under the BIM framework as described above.

[0111] Based on the above description, the method of the present invention also provides the following embodiments. Taking the riverbed powerhouse dam section of a gravity dam as an example, the main structure of the powerhouse dam section extracted from the BIM design software using the Xbim toolbox is shown in Figure 2(a). It can be seen that although the non-structural components and other irrelevant structures in the model have been filtered out, there are still some detailed features, which makes the model too complex and cannot support automatic hexahedral meshing.

[0112] First, advanced virtual topology operations are used to remove complex features attached to the main structure, such as through holes (vents) and grooves (plane gate grooves, corridor drainage ditches) in the dam model. Then, the narrow and long faces formed by the chamfers in the corridor are decomposed. Finally, the cleaned and adjusted model (as shown in Figure 2(b)) is divided into hexahedral meshes.

[0113] Next, a sub-model view definition for hydraulic structure analysis is constructed based on the BIM metadata model. Node unit information is extracted from the grid model according to the hydraulic structure analysis sub-model view definition, and other physical material information is extracted from the IFC information model. Custom boundary conditions including gravity, water pressure load and foundation constraints are added, and stored in XML format to form a general structural analysis data model for hydraulic structures (such as Figure 3 Finally, a data interface was constructed between the commercial finite element analysis software ABAQUS and the general structural analysis model of the powerhouse dam section, and a calculation file in inp format was generated and imported into ABAQUS.

[0114] Based on the above description, the method of the present invention also provides the following embodiments, taking the original three-dimensional terrain surface of a high arch dam (as shown in Figure 4 (a)) as an example, to prove the importance of the grid smoothing algorithm proposed by the present invention in the process of constructing a terrain entity grid model. This embodiment first uses C++ language to develop the grid smoothing algorithm based on human visual perception and hybrid low-pass filter on the basis of the basic geometry library (BGL). It can be seen that the algorithm effectively eliminates the noise and small-scale landform features on the terrain surface, and only retains the large-scale terrain undulation features (as shown in Figure 4 (b)). In addition, the boundary of the terrain surface has not shrunk, and the volume shrinkage rate of the terrain entity within 1.5 times the dam height below the foundation is only 2.14%, which can meet the needs of hydraulic structure analysis.

[0115] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims

1. A method for constructing a general structural analysis model of hydraulic structures under the BIM framework, characterized in that: The construction method comprises the following steps: Step S1: Use tools that support the IFC standard to extract the BIM entity model, screen the key components of the hydraulic structure, and export relevant geometric data to support the subsequent construction of the structural analysis model; Step S2: Using advanced virtual topology operations, the topology of the complex hydraulic structure entity model is adjusted and edited without changing the geometric part of the model, and then meshing is performed; Step S3: Based on the visual perception method, the visual saliency of the mesh vertices is calculated by local contrast and global sparsity, the terrain mesh features are distinguished, and the terrain mesh is smoothed by a hybrid low-pass filter, and then the smoothed terrain surface is meshed by an automatic meshing algorithm; Step S4: Based on the BIM metadata model, construct a sub-model view of hydraulic structure analysis, extract and integrate structural analysis parameters, and generate a standardized general structural analysis data model; Step S5: Construct a data interface for communication with the structural analysis software.

2. The method for constructing a general structural analysis model of a hydraulic structure under a BIM framework according to claim 1 is characterized in that: In step S1, the method for extracting the BIM entity model includes: using the IFC information direct access method based on the standard data access interface, using the IFC toolbox to screen the entity model of the main structure of the hydraulic structure, extracting key components including the dam body, gates, energy dissipation facilities and water inlets, and exporting the geometric data information of the entity model in STEP format or SAT format to ensure the adequacy and completeness of the model.

3. The method for constructing a general structural analysis model of a hydraulic structure under a BIM framework according to claim 1 is characterized in that: Step S2 includes the following steps: Step S201: performing basic virtual topological operations, including fusion, segmentation, connection, and construction, and repeatedly performing these operations in a specific order to form advanced virtual topological operations, including removing through holes, removing grooves, and model decomposition; Step S202: Identify small features that are attached to the main structure of the hydraulic structure but have little impact on the overall analysis results of the model and significantly increase the difficulty of model meshing, including corridors and holes in the concrete dam body and track grooves built into different gates; Step S203: remove the above-mentioned fine geometric features through advanced virtual topology operations, and use an automatic meshing algorithm to mesh the main structure.

4. The method for constructing a general structural analysis model of a hydraulic structure under a BIM framework according to claim 1, characterized in that: Step S3 includes the following steps: Step S301: Calculate any given vertex v in the terrain grid by using local contrast and global sparsity, and K-means clustering algorithm i The local contrast S l (v i ) and the global sparsity S g (r i ), including the following sub-steps: Step S301.1: Calculate the local contrast S using formula (1) l (v i ), the calculation formula is as follows: Where U i are the m faces closest to the vertex, that is, σ a Take it as 0.6; ri is the size of the height map (the Euclidean distance from itself to the mesh surface along the ray perpendicular to the cutting plane); Z ri represents the Zernike coefficient; Step S301.2: Calculate the global sparsity S using formula (2) g (v i ), the calculation formula is as follows: In the formula, Represents all vertices in the mesh, vertices with the same features have the same sparsity; Step S301.3: Perform cluster analysis on similar vertices using the K-means clustering algorithm, replace the vertices in formula (2) with the center points of the corresponding clusters, and derive the sparsity of the cluster using formula (3). The sparsity calculation formula for the cluster is as follows: In the formula, c i and c j They represent the center points of cluster i and cluster j in the feature space, K is the total number of clusters after clustering, n is the number of vertices in the grid, and n j represents the number of vertices in cluster j; Step S301.4: After evaluating the sparsity of each cluster sample, the sparsity of a single vertex is calculated by an appropriate interpolation method. For a given vertex v i , the global sparsity of the vertex is calculated by formula (4): Where, T i are the m clusters closest to the vertex; σ a The value is 0.3, which is closer to the vertex v in the feature space. i The cluster with larger weight is assigned; Step S302: When the local contrast S l (v i ) and the global sparsity S g (v i ) are calculated respectively, the visual saliency of the mesh vertices is calculated by formula (5), and it is normalized by formula (6) as the feature scale to distinguish the size features. The calculation formula is as follows: S(v i )=S l (v i )+λS g (v i ) (5) In the formula, λ represents the weight factor, S i To obtain the visual saliency of vertex i by considering both local contrast and global sparsity, S max is the most significant value among the mesh vertices, S min is the lowest significant value among the mesh vertices; Step S303: Select an appropriate threshold according to the actual situation of the terrain surface, and set the vertices larger than the threshold as small-scale feature vertices (set the label variable ε i =1), and the vertices smaller than the threshold are set as large-scale feature vertices (set the label variable ε i =0); Step S304: Use a mixed low-pass filter to perform terrain mesh smoothing, that is, use different cutoff frequencies at different terrain mesh vertices. i The cut-off frequency at can be determined by the following formula: s i =α(1-ε i )+be i (7) In the formula, σ i is the cutoff frequency at vertex i, α is the large-scale feature point (ε i =0) participates in the cutoff frequency of geometric reconstruction, β is the small-scale feature point (ε i =1) is the cutoff frequency for geometric reconstruction; Step S305: using an automatic meshing algorithm to perform quadrilateral meshing on the smoothed terrain surface, thereby achieving the goal of generating terrain solid hexahedral units.

5. The method for constructing a general structural analysis model of a hydraulic structure under a BIM framework according to claim 4 is characterized in that: In step S3, the time complexity of calculating the saliency of all vertices is O(n 2 ), where n is the number of vertices in the grid. In order to reduce the computational complexity, the K-means clustering algorithm is used to adaptively sample different spaces by clustering the vertices into no more than 50 clusters. The number of clusters is significantly less than the actual number of vertices, thereby significantly reducing the computational complexity.

6. The method for constructing a general structural analysis model of a hydraulic structure under a BIM framework according to claim 1, characterized in that: Step S4 includes the following steps: Step S401: constructing a sub-model view definition for hydraulic structure analysis based on the BIM metadata model; Step S402: extracting unit node information, physical and mechanical parameters, structural loads, boundary conditions and other related information from the grid model and the global BIM data model according to the specific information interaction requirements in the model view definition; Step S403: Describe the necessary information required for the structural analysis model in a unified and standard form to form a universal data model that is independent of the expression language and the application software.

7. The method for constructing a general structural analysis model of a hydraulic structure under a BIM framework according to claim 1, characterized in that: In step S5, the constructed data interface is used to implement the following three functions: (1) Parse the general data model and read the key information required for structural analysis; (2) Perform data information matching, integrating the geometric topological information of the grid cells obtained from the grid cell model with the material information of the main structure obtained from the global IFC model to ensure the consistency of information; (3) Generate calculation files in a specific format according to the requirements of the structural analysis software.

8. A system for constructing a universal structural analysis model of a hydraulic structure under a BIM framework, which is applied to the method for constructing a universal structural analysis model of a hydraulic structure under a BIM framework as claimed in claims 1 to 7, characterized in that: The general structural analysis model construction system of hydraulic structures under the BIM framework includes: The geometric model export module includes: a structural analysis unit, which is used to screen the structures that need to be analyzed in the main body of the hydraulic structure; a solid model export unit, which is used to select the file export format and add additional information; The solid model preprocessing module includes: a model adjustment unit, which is used to select appropriate advanced virtual topology operations to process fine features on the solid model; a mesh automatic division unit, which is used to select appropriate automatic division algorithms according to the features of the solid model to perform mesh division on the processed solid model; The terrain surface preprocessing module includes: a surface smoothing module, which is used to distinguish and filter small-scale features on the terrain surface, and only retain large-scale terrain features; a grid automatic subdivision unit, which is used to select a suitable algorithm to divide the surface unit and extend it in the vertical direction to form a terrain solid grid unit; Mesh model analysis module: used to analyze the above-mentioned entity unit information that has been segmented, including the number of units, the number of nodes, the unit number, the node number, the node unit relationship, and the node coordinates; The structural analysis model creation module includes: an information extraction unit, which is used to extract information from the grid model and material information and load information from the IFC model; a constraint application unit, which is used to batch select surface units or node units and add corresponding constraints; a general structural analysis model construction unit, which is used to import the pre-compiled sub-model view definition for hydraulic structure analysis and extract and integrate the necessary information in the model based on the sub-model view definition; Data interface module: used to select the formats supported by different finite element commercial software, perform model analysis and information matching, and generate calculation files in a specific format.

9. An electronic device, characterized in that: It comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, it can implement the method for constructing a general structural analysis model of hydraulic structures under the BIM framework as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer program is used to run the method for constructing a general structural analysis model of hydraulic structures under the BIM framework as described in any one of claims 1 to 7.

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