A method for integrating BIM and SAP2000 foundation pit excavation calculation

Abstract

This invention discloses a method for integrating BIM and SAP2000 foundation pit excavation calculations, comprising: establishing a BIM parametric model using Revit software; the three-dimensional parametric model effectively integrates various relevant project information and specifies naming conventions for the structures and attributes required for subsequent calculations and analyses; exporting the three-dimensional BIM model as a common IFC file; obtaining the geometric information of all instance elements and the parameter attributes of model elements in the IFC file to extract key model data required for calculations; based on the obtained BIM model parameters and geometric information, establishing a foundation pit model suitable for load-structure analysis using a program; generating an .S2K format file and importing it into SAP2000 for calculation and analysis, thereby realizing the integrated BIM-SAP2000 foundation pit calculation technology.

Description

Technical Field

[0001] This invention relates to the field of deep foundation pit (e.g., subway stations, underground municipal roads, underground municipal utility tunnels, etc.) excavation and BIM-SAP2000 data interface technology, and particularly to a method for integrating BIM and SAP2000 foundation pit excavation calculation. Background Technology

[0002] Urban construction is accelerating rapidly, leading to increasing pressure on surface transportation. Building subway networks to alleviate urban traffic congestion has become a hot topic and a future plan for many cities. Subway construction naturally involves deep foundation pit engineering. Subway lines and station locations are often situated in densely populated areas or key municipal sites, making the projects relatively concealed, with complex construction environments, numerous influencing factors, and stringent quality requirements. Improper handling of any issues during construction can create a series of safety hazards for the existing environment and the construction site.

[0003] The application and research of BIM have developed rapidly in fields such as building structures. Many structural design software programs have mature data model conversion interfaces with BIM software, and their principles are basically based on the IFC intermediate format. However, in the field of geotechnical engineering, due to reasons such as file format and parameter selection, there are relatively few BIM application examples. To address the above issues, a reasonable design of the support structure for excavation engineering should be made from the perspective of design based on the excavation calculation of foundation pit engineering. However, the current design and calculation analysis of deep foundation pit engineering are still in a state of separation, making it difficult to complete efficient engineering tasks. Summary of the Invention

[0004] This invention provides a method for integrating BIM and SAP2000 foundation pit excavation calculations, which solves or at least partially solves the technical problem in the prior art where the design and calculation analysis of deep foundation pit projects are separated, making it difficult to complete efficient engineering tasks.

[0005] To address the aforementioned technical problems, this invention provides a method for integrating BIM and SAP2000 foundation pit excavation calculations, comprising:

[0006] S1: Establish a BIM parametric model and export the BIM parametric model as an IFC file. Identify and label the attributes according to the type of engineering object corresponding to the graphic element. The IFC file includes multiple graphic elements. The geometric and parameter information contained in the graphic elements is stored in the form of data blocks. The graphic elements have a corresponding relationship with the engineering objects. The types of engineering objects include foundation pit support structure, foundation pit internal support and soil.

[0007] S2: Use the parsing program to parse the IFC file, identify the engineering objects corresponding to the graphic elements according to the identification attributes of the annotations, and then extract the geometric information and parameter information contained in the graphic elements. The geometric information is matched and bound with the physical parameters. The extracted geometric information and parameter information are stored as OBJ files and JSON files respectively. The geometric information includes the vertex coordinates of key geometric graphics and the topological information of the graphics. The parameter information includes physical parameters and construction parameters.

[0008] S3: Based on the geometric information obtained by the analysis program, extract the coordinates of key geometric points from the foundation pit support structure and the internal support of the foundation pit, and record the key elevation information. Then, sort the extracted key geometric point coordinates. Based on the sorted nodes and key elevation information, generate the calculation elements for SAP2000 foundation pit excavation calculation, and form a format file that supports SAP2000 calculation. The key elevation information includes the elevation of the internal support of the foundation pit and the elevation of the layer interface of the foundation soil outside the foundation pit.

[0009] S4: Import the format file that supports SAP2000 calculation into SAP2000 for calculation and analysis, so as to realize the integration of BIM and SAP2000 foundation pit excavation calculation.

[0010] In one implementation, step S1, which involves identifying attribute labels based on the type of the engineering object, includes:

[0011] The solid structure of the foundation pit support is labeled using an elastic constitutive model, the solid structure of the support inside the foundation pit is labeled using a beam element model, and the soil is labeled using a soil constitutive model.

[0012] In one implementation, when S2 parses the IFC file using the parsing program, it designs complete primitives as classes and the information contained within the primitives as class members. The method for extracting the geometric information contained in the primitives is as follows:

[0013] The triangular element analytical function is used to parse each element in the IFC file one by one to obtain the key geometric vertex coordinates and topological information of each element in the BIM parametric model.

[0014] In one implementation, the method for extracting parameter information contained in the primitives in S2 is as follows:

[0015] The physical and construction parameters of the engineering objects corresponding to each graphic element are obtained by using the numerical analysis function of the model attribute parameters.

[0016] In one implementation, step S2, which involves matching and binding geometric information with physical parameters, includes:

[0017] When the parsing program performs a parsing operation on a data block of a graphic element, it generates a universally unique identifier (UUID) and assigns it to all data in that data block.

[0018] The generated UUID is transferred to both the OBJ and JSON files to achieve matching and binding between the geometric information in the OBJ file and the physical parameter information in the JSON file.

[0019] In one implementation, the key elevation information in step S3 includes the elevation of the soil layer boundary, the elevation of the support installation, and the elevation of the excavation face.

[0020] In one implementation, step S3 generates calculation elements for SAP2000 foundation pit excavation calculation based on the sorted nodes and key elevation information, including:

[0021] Based on the extracted key elevation information, the projection points on the XOY plane are copied to the corresponding elevations. All nodes are sorted and numbered. All nodes are traversed and arranged counterclockwise to generate a region. The projection points on the XOY plane are the points obtained by projecting the geometric key points onto the XOY plane.

[0022] The coordinates of the support within the foundation pit are determined based on the identification attributes and UUID obtained by the parsing program. The node numbers of the two nodes in SAP2000 are obtained by coordinate matching, and the strings are output to the .S2K file to generate the corresponding frame units.

[0023] Earth pressure at key elevation nodes is calculated using elevation interpolation.

[0024] The surface spring in SAP2000 is used to simulate the soil spring. By traversing the elevation of the nodes associated with the surface region, all surface regions below the excavation surface elevation are retrieved, and the retrieved surface regions are associated with the corresponding elevation.

[0025] In one implementation, all nodes are traversed and arranged counterclockwise to generate a region, including:

[0026] Obtain the number of critical elevations to determine the number of nodes that need to be copied;

[0027] Copy the nodes on the projection plane to their corresponding elevations;

[0028] Connect each node to its corresponding node at the same level and its lower level in a counterclockwise direction to form a region geometry.

[0029] The OBJ geometry to which the region belongs is determined based on the coordinates of each node within the region, and the corresponding physical parameters are matched using the UUID value of the OBJ geometry. All information of the region is then output according to the data structure of the .S2K file, where the OBJ geometry corresponds to the OBJ file.

[0030] In one embodiment, after step S2, the method further includes: organizing the information extracted from the IFC file, serializing it according to the data structure in the SAP2000 computing software, and obtaining the coordinates and node number of each node.

[0031] In one embodiment, the method further includes: setting the boundary conditions required for calculation for the nodes corresponding to the node numbers corresponding to the minimum Z coordinate values ​​in the index node coordinates.

[0032] Compared with the prior art, the advantages and beneficial technical effects of the present invention are as follows:

[0033] This invention provides a method for integrating BIM and SAP2000 foundation pit excavation calculations. It utilizes Revit software to create a BIM parametric model. This 3D parametric model effectively integrates various relevant project information and establishes naming conventions for the structures and attributes required for subsequent calculations and analyses. The 3D BIM model is exported as a generic IFC file. A parsing program obtains the geometric information and parameter attributes of all instance units (primitives) in the IFC file, thereby extracting the key model data required for calculations. Then, based on the geometric information obtained from the parsing program, the coordinates of key geometric points are extracted from the foundation pit support structure and internal supports, while simultaneously recording key elevation information. The extracted key geometric point coordinates are then sorted. Based on the sorted nodes and key elevation information, calculation elements for SAP2000 foundation pit excavation calculations are generated, forming an .S2K format file. This file is imported into SAP2000 for calculation and analysis, achieving the integration of BIM and SAP2000 foundation pit calculations. This solves the technical problem in existing technologies where deep foundation pit engineering design and calculation analysis are separated, making it difficult to complete efficient engineering tasks. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a flowchart of a method for integrating BIM and SAP2000 foundation pit excavation calculations provided in an embodiment of the present invention;

[0036] Figure 2This is a schematic diagram of OBJ primitive components in an embodiment of the present invention. OBJ primitive components are a lightweight geometric definition file format that can be flexibly compatible with various three-dimensional geometry editing programs or software.

[0037] Figure 3 This is a schematic diagram of a JOSN file in an embodiment of the present invention. A JOSN file is a lightweight data exchange format that is easy for humans to read and write as well as easy for machines to parse. Its data structure is a serialized set of objects. The data in the file is stored in the form of key-value pairs. Its data structure is clear and suitable for parameter matching and reading.

[0038] Figure 4 This is a schematic diagram of the inner support and the surface node in an embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram of discrete point projection in an embodiment of the present invention;

[0040] Figure 6 This is the convex polygon sorting algorithm in this embodiment of the invention (for subway station-type foundation pits, geometric reconstruction involves sorting problems, and a general algorithm is used for sorting the vertices of convex graphics).

[0041] Figure 7 This is a schematic diagram of the initial base point in the vertex sorting algorithm for concave polygons in this embodiment of the invention. (Unlike convex polygons, concave polygons do not have a universal vertex sorting algorithm. Their sorting algorithm varies depending on the shape. This invention designs a vertex sorting algorithm suitable for this model.)

[0042] Figure 8 This is a schematic diagram of the base point moving forward and clearing nodes in the concave polygon vertex sorting algorithm in an embodiment of the present invention;

[0043] Figure 9 This is a schematic diagram of changing the search direction in the concave polygon vertex sorting algorithm in an embodiment of the present invention;

[0044] Figure 10 This is a schematic diagram of a replication node in an embodiment of the present invention;

[0045] Figure 11 This is a schematic diagram of the file import interface in an embodiment of the present invention. Detailed Implementation

[0046] This invention provides an integrated method for BIM and SAP2000 foundation pit excavation calculation. It primarily uses Revit software to establish a BIM parametric model, preprocesses the IFC file, and extracts the key model data required for calculation. However, using BIM technology for parametric modeling of deep foundation pit projects requires addressing the following key issues: (1) Integrating specific information into the parametric model. (2) Defining the identification attributes of engineering objects to ensure efficient and accurate identification by the parsing program. (3) Extracting the geometric model of engineering objects. (4) Extracting the physical parameter information of engineering objects. (5) Binding the attributes of engineering objects to their geometric entities.

[0047] To achieve integrated BIM-SAP2000 foundation pit calculation technology, it is necessary to create a foundation pit model suitable for load-structure analysis using a program based on the acquired BIM model parameters and geometric information. This model is then generated as a .S2K file and imported into SAP2000. When simulating foundation pit excavation using SAP2000, the following five calculation elements need to be represented in the model: foundation pit support structure, internal foundation pit bracing, external earth pressure on the foundation pit, internal soil springs, and excavation face. Generating the calculation model from the .S2K file requires addressing the following key issues: extracting geometric information, node sorting, and generating calculation elements (regions, frame elements, external earth pressure on the foundation pit, and soil springs).

[0048] In summary, this invention focuses on parametric BIM models, developing an interface program for BIM-SAP2000 software. It establishes a foundation pit model suitable for load-structure analysis, generates an .S2K format file, imports it into SAP2000, and achieves BIM-SAP2000 software integration. The application and research of BIM have developed rapidly in fields such as building structures. Many structural design software programs and BIM software already have relatively mature data model conversion interfaces, primarily based on the IFC intermediate format. However, in the geotechnical engineering field, due to file formats and parameter selection limitations, BIM application examples are relatively few. This method promotes the application of BIM in mechanical calculations, compensating for the shortcomings of BIM in foundation pit calculation technology. Furthermore, compared with traditional manual repetitive modeling, this method significantly improves industrial production efficiency, thus significantly solving the current problem of the disconnect between engineering design and calculation analysis. Therefore, this invention has significant technical advantages, broad application prospects, and is worthy of trial and promotion within the industry.

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] This invention provides a method for integrating BIM and SAP2000 foundation pit excavation calculations, comprising:

[0051] S1: Establish a BIM parametric model and export the BIM parametric model as an IFC file. Identify and label the attributes according to the type of engineering object corresponding to the graphic element. The IFC file includes multiple graphic elements. The geometric and parameter information contained in the graphic elements is stored in the form of data blocks. The graphic elements have a corresponding relationship with the engineering objects. The types of engineering objects include foundation pit support structure, foundation pit internal support and soil.

[0052] S2: Use the parsing program to parse the IFC file, identify the engineering objects corresponding to the graphic elements according to the identification attributes of the annotations, and then extract the geometric information and parameter information contained in the graphic elements. The geometric information is matched and bound with the physical parameters. The extracted geometric information and parameter information are stored as OBJ files and JSON files respectively. The geometric information includes the vertex coordinates of key geometric graphics and the topological information of the graphics. The parameter information includes physical parameters and construction parameters.

[0053] S3: Based on the geometric information obtained by the analysis program, extract the coordinates of key geometric points from the foundation pit support structure and the internal support of the foundation pit, and record the key elevation information. Then, sort the extracted key geometric point coordinates. Based on the sorted nodes and key elevation information, generate the calculation elements for SAP2000 foundation pit excavation calculation, and form a format file that supports SAP2000 calculation. The key elevation information includes the elevation of the internal support of the foundation pit and the elevation of the layer interface of the foundation soil outside the foundation pit.

[0054] S4: Import the format file that supports SAP2000 calculation into SAP2000 for calculation and analysis, so as to realize the integration of BIM and SAP2000 foundation pit excavation calculation.

[0055] Please see Figure 1 This is a flowchart of a method for integrating BIM and SAP2000 foundation pit excavation calculations provided in an embodiment of the present invention.

[0056] Specifically, step S1 of the above method is parametric modeling, step S2 is the extraction of geometric and parameter information of the model, and the extracted information serves as the basis for subsequent foundation pit analysis and calculation, step S3 is the extraction of key point coordinates and recording of elevation information based on the extracted geometric and parameter information, and further generating calculation elements of the foundation pit calculation model, and step S4 is to use the file obtained in S3 to perform calculation and analysis in SAP2000.

[0057] S1 uses Revit software to build a parametric BIM model. This 3D parametric model effectively integrates various relevant project information and establishes naming conventions for the structures and attributes required for subsequent calculations and analyses. The 3D BIM model is then exported as a generic IFC file. In Revit, elements are the basic building blocks of the BIM model. Within the IFC file, all information about each element is described line by line within the same data block, forming a cohesive whole. When reading and parsing the IFC file, object-oriented programming is employed, designing complete elements as classes and the information contained within each element as class members, ensuring the matching of all element information.

[0058] S2 uses a design parsing program to obtain the geometric information and parametric attributes of all instance elements in the IFC file, in order to extract the key model data (geometric and parametric information) required for calculation. The parsing program operates throughout the entire BIM model data extraction process. Based on the data structure of the IFC file, it parses the IFC file to extract the geometric model information required for engineering calculations, the physical parameter information attached during parametric modeling, and the construction information (i.e., special elevation markers used in BIM modeling). When the IFC file of the BIM model is uploaded to the parsing program, the program will perform the above functions and determine whether the element is a solid element based on the constitutive model attribute.

[0059] S3 and S4, based on the acquired BIM model parameters and geometric information, generate calculation elements for SAP2000 foundation pit excavation calculation, generate .S2K format files, and import them into SAP2000 for calculation and analysis, thereby realizing the integration of BIM-SAP2000 foundation pit calculation.

[0060] In one implementation, step S1, which involves identifying attribute labels based on the type of the engineering object, includes:

[0061] The solid structure of the foundation pit support is labeled using an elastic constitutive model, the solid structure of the support inside the foundation pit is labeled using a beam element model, and the soil is labeled using a soil constitutive model.

[0062] Specifically, since the constitutive model is the parameter that best reflects the specific differences between engineering objects, and the foundation pit support structure is generally in an elastic state, this implementation method uses an elastic constitutive model to label the foundation pit support structure entity. Lateral support entities are all labeled using beam element models. In the specific implementation process, soil and rock constitutive models (such as the PH model, Mohr-Coulomb model, Cambridge model, etc.) can be used to label the constitutive models of the soil involved in the foundation pit engineering. The parsing program will identify the soil and foundation pit support structure entities in the BIM model based on the constitutive model label of each element block, facilitating subsequent data parsing and realizing the identification and classification of engineering objects.

[0063] In one implementation, when S2 parses the IFC file using the parsing program, it designs complete primitives as classes and the information contained within the primitives as class members. The method for extracting the geometric information contained in the primitives is as follows:

[0064] The triangular element analytical function is used to parse each element in the IFC file one by one to obtain the key geometric vertex coordinates and topological information of each element in the BIM parametric model.

[0065] In the specific implementation process, after creating the BIM model in Revit software, an IFC file is exported according to the IFC2×3 standard. The TriangulationElement (triangular element parsing function) class member functions within the IfcGeom namespace of the open-source toolkit IFCOpenShell are used to parse each element in the IFC file one by one, thereby obtaining the complete geometric information of each element in the model and the topological information between the geometric elements. IfcGeom is a namespace in the toolkit that contains various functions responsible for acquiring and manipulating the geometric data of the BIM model. TriangulationElement is a function that obtains the geometric points and topology within the model data block in the form of a triangular mesh. The geometric information follows the principle of parsing first and then reconstructing in computer graphics. When parsing the IFC file, the program can only obtain the coordinates of the key geometric vertices of the elements and the topological information of the graphics, such as: the two vertices that constitute a line segment, the four vertices that constitute a region, and the six regions that constitute a solid. After obtaining this data, these elements are reconstructed according to triangular faces, and the geometric data of all engineering objects is converted into OBJ file format. Figure 2 The image shown is an OBJ primitive component. OBJ files are a lightweight geometric definition file format that is flexibly compatible with various 3D geometry editing programs or software. The extracted geometric information can not only be parsed but also transmitted to the front end for display.

[0066] In one implementation, the method for extracting parameter information contained in the primitives in S2 is as follows:

[0067] The physical and construction parameters of the engineering objects corresponding to each graphic element are obtained by using the numerical analysis function of the model attribute parameters.

[0068] In the specific implementation process, the physical parameter information within the engineering object data block is retrieved line by line using the IfcPropertySingleValue (model attribute parameter numerical parsing function) class member function of IFC_PARSE_API under the IFC2×3 namespace in the IFCparse header file of the IFCOpenShell toolkit. (The engineering object data block contains all the information of a single BIM element; the engineering object data block is the computerized data representation of BIM model elements.) The corresponding parameter information is then saved in a JSON format file. Figure 3 This is an example of a JSON file. `IfcPropertySingleValue` is used to read the attribute names and corresponding values ​​stored during BIM parametric modeling. JSON is a widely accepted, lightweight data exchange format that is easy for humans to read and write, and also easy for machines to parse. The data structure of a JSON file itself is a serialized set of objects, with data stored in key-value pairs. Its data structure is clear and suitable for parameter matching. The library functions in the open-source toolkit nlohmann can easily perform various operations on JSON files, facilitating subsequent matching of physical parameters with the geometric model. During the overall BIM model analysis, geometric information and parameter information are parsed separately. The geometry generates OBJ files, and all attribute names and corresponding parameters generate JSON files. At this point, there is no direct correspondence between the geometric information and parameter information in the primitives. Therefore, before splitting and parsing the primitive data blocks, a globally unique identifier (UUID) is applied to all member information of the primitive, and the UUID is used as a specific binding attribute for geometry and parameters. Matching the same UUID allows the re-retrieval of the correspondence between the geometry and its parameters. JSON files are used as a scripting language for web pages. They are highly extensible and facilitate communication with the front end.

[0069] In one implementation, step S2, which involves matching and binding geometric information with physical parameters, includes:

[0070] When the parsing program performs a parsing operation on a data block of a graphic element, it generates a universally unique identifier (UUID) and assigns it to all data in that data block.

[0071] The generated UUID is transferred to both the OBJ and JSON files to achieve matching and binding between the geometric information in the OBJ file and the physical parameter information in the JSON file.

[0072] In the specific implementation process, to re-match and bind the geometric information and physical parameters of engineering objects, a universally unique identifier (UUID) is used to establish a connection between the two. When the parsing program parses a data block, it first generates a UUID and assigns it to all data in that data block, then transmits the UUID value to the geometry OBJ file and the attribute JSON file. By using key-value pairs to match the geometry within the OBJ file and the attributes in the JSON file with the same UUID, the binding of engineering objects can be achieved.

[0073] In one implementation, the key elevation information in step S3 includes the elevation of the soil layer boundary, the elevation of the support installation, and the elevation of the excavation face.

[0074] In the specific implementation process, such as Figure 4 As shown, to facilitate the creation of the nodes required for the frame elements and soil springs, a new program (i.e., a coordinate extraction program) needs to be written to extract the coordinates of geometric key points (the vertices of the support structure and the vertices of the foundation pit supports) from the foundation pit support structure and the foundation pit internal supports, respectively, and project them onto the XOY plane, as shown below. Figure 5 As shown. Simultaneously, key elevation information such as the excavation face, internal support elevation, and soil layer boundary elevation are recorded to complete the extraction of geometric information.

[0075] In SAP2000 software, all geometric modeling and load application are node-based. To generate ordered nodes, the geometric key points need to be sorted:

[0076] ① For the vertex sorting problem of convex graphs, a general algorithm is used, such as... Figure 6 As shown. Establish a local coordinate system with the centroid of the quadrilateral as the origin, and calculate the coordinates of the vectors formed by each vertex and the origin in the local coordinate system; calculate the angle between each vector and the X' axis of the local coordinate system; sort the angles in ascending (or descending) order and index the corresponding vertices to achieve the counterclockwise (or clockwise) sorting of the vertices of the convex polygon.

[0077] ② Unlike convex polygons, concave polygons do not have a universal vertex sorting algorithm; their sorting algorithm varies depending on the shape. This invention designs a vertex sorting algorithm suitable for this model, realizing vertex sorting for this projected concave shape. For example... Figure 7 As shown, the circular area in the diagram represents the range of the search step size. The search step size needs to be estimated in advance based on the distance between geometric key points, and it is advisable to take a value slightly larger than the distance between two points. The algorithm specifies four search modes: upward search, downward search, leftward search, and rightward search. A node in the diagram is selected as the initial search base point, stored in a sorted container, and its sequence is set to 1. The initial search direction is specified and maintained to the right until the corner of the lattice is reached. When a node simultaneously meets the requirements of the search step size range and the search direction, the node is captured and stored in the sorted container. Figure 8 As shown, once a node is captured, the search base point is immediately moved to that capture point according to the current search direction, while the original search base point is cleared. This node acquisition method is maintained until a corner of the grid is reached. Figure 9 As shown, when the current search node is a corner of the matrix, continuing to execute the capture command in the current search direction will not yield a new node. In this case, the search direction is changed (e.g., upwards), and an attempt is made to capture the node in the new direction. If a new node is captured, the capture will continue in the new search direction until the next corner; if a new node cannot be captured, the search direction will be changed again. Since the algorithm clears the original base point each time it moves, all nodes along the movement path of the search base point will be cleared, and the number of nodes in the matrix will gradually decrease until only one node remains. At this point, all nodes have been stored in a sorted container, and the node can be obtained by reading the index of the sorted container. Figure 4 The result of sorting the nodes.

[0078] After completing the node sorting, various calculation elements (region, frame element, external earth pressure of the foundation pit, soil spring) need to be generated based on the node information. For example... Figure 10 As shown, based on the key elevation information extracted earlier, the projection points on the XOY plane are copied to various elevation locations (illustrated using three-layer nodes). Finally, an .S2K file that can be read by SAP2000 is output. The file is then imported into SAP2000 (e.g., ...). Figure 11 (as shown) and calculate.

[0079] In one implementation, step S3 generates calculation elements for SAP2000 foundation pit excavation calculation based on the sorted nodes and key elevation information, including:

[0080] Based on the extracted key elevation information, the projection points on the XOY plane are copied to the corresponding elevations. All nodes are sorted and numbered. All nodes are traversed and arranged counterclockwise to generate a region. The projection points on the XOY plane are the points obtained by projecting the geometric key points onto the XOY plane.

[0081] The coordinates of the support within the foundation pit are determined based on the identification attributes and UUID obtained by the parsing program. The node numbers of the two nodes in SAP2000 are obtained by coordinate matching, and the strings are output to the .S2K file to generate the corresponding frame units.

[0082] Earth pressure at key elevation nodes is calculated using elevation interpolation.

[0083] The surface spring in SAP2000 is used to simulate the soil spring. By traversing the elevation of the nodes associated with the surface region, all surface regions below the excavation surface elevation are retrieved, and the retrieved surface regions are associated with the corresponding elevation.

[0084] In one implementation, all nodes are traversed and arranged counterclockwise to generate a region, including:

[0085] Obtain the number of critical elevations to determine the number of nodes that need to be copied;

[0086] Copy the nodes on the projection plane to their corresponding elevations;

[0087] Connect each node to its corresponding node at the same level and its lower level in a counterclockwise direction to form a region geometry.

[0088] The OBJ geometry to which the region belongs is determined based on the coordinates of each node within the region, and the corresponding physical parameters are matched using the UUID value of the OBJ geometry. All information of the region is then output according to the data structure of the .S2K file, where the OBJ geometry corresponds to the OBJ file.

[0089] In one embodiment, after step S2, the method further includes: organizing the information extracted from the IFC file, serializing it according to the data structure in the SAP2000 computing software, and obtaining the coordinates and node number of each node.

[0090] After obtaining all the information required for the calculation (step S2), the information extracted from the IFC file needs to be organized and serialized according to the data structure in the calculation software (SAP2000). The node information during serialization includes both XYZ coordinates and node numbers; the node number can be retrieved using the node's coordinates.

[0091] In one embodiment, the method further includes: setting the boundary conditions required for calculation for the nodes corresponding to the node numbers corresponding to the minimum Z coordinate values ​​in the index node coordinates.

[0092] Apply fixed constraints to all indexed nodes, i.e. set the boundary conditions required for the calculation.

[0093] To more clearly illustrate the implementation process of the method of the present invention, the following description is provided in conjunction with the appendix. Figures 1-8 The method of the present invention will be further described in detail below.

[0094] When using the method of the present invention, the operation steps are as follows:

[0095] Step 1: Use Revit software to create a BIM parametric model. In particular, draw the elevation of the excavation face and label it with the keyword "excavation". Export the IFC file according to the 2×3 standard.

[0096] Step 2: Input the IFC file exported from the parametric model into the parsing program. The parsing program traverses the IFC file and parses the primitive blocks in each data block one by one.

[0097] Step 2 in this invention includes the following steps:

[0098] Step 2.1: When the parsing program reads the image data block, it will generate a globally unique identifier (UUID) based on the current time as the basic attribute of the image element.

[0099] Step 2.2: Subsequently, the functions within the IfcGeom namespace are called to parse the geometric information of the current primitive, and the TriangulationElement function is used to decompose each face of the primitive into triangular patches. The parsed primitive geometric information is written to the .obj file according to the obj data structure, and the primitive UUID from Step 2.1 is also written to the corresponding position of the primitive in the .obj file. Figure 1 The image shown is an OBJ primitive component.

[0100] Step 2.3: Then, use the IfcPropertySingleValue class member function of IFC_PARSE_API to obtain the physical parameter information in the original data block line by line, and save the corresponding parameter information and the original UUID in Step 2.1 in a JSON format file.

[0101] Step 2.4: After traversing all BIM entity elements, begin parsing the excavation elevations in the BIM model. Again, traverse all elements in the IFC file, creating pointers to access the elements in the IfcBuildingStorey namespace: IfcBuildingStorey::Argument(7) (elevation name) and IfcBuildingStorey::Argument(9) (elevation value). Obtain the elevation value corresponding to the keyword "excavation" in the elevation name; this is the excavation face elevation. Sort all excavation face elevation values ​​and write them to the JSON file in Step 2.3.

[0102] Step 3: As Figure 4 As shown, the coordinates of geometric key points are extracted from the foundation pit support structure and the internal support of the foundation pit, and then projected onto the XOY plane. Figure 5 Simultaneously record key elevation information such as the excavation face, internal support elevation, soil layer boundary elevation, and excavation face.

[0103] Step 4: Extracted geometric key points are obtained through concave polygons ( Figures 7-9 Sort using sorting algorithms.

[0104] Step 5: Based on the extracted key elevation information (including the elevation of soil layer boundaries, support installation elevation, and excavation face elevation), copy the projection points on the XOY plane to each elevation location, sort and number all nodes, such as... Figure 10As shown.

[0105] Step 6: Write a loop to traverse all nodes and generate the region in a counter-clockwise order.

[0106] Step 6 in this invention includes the following steps:

[0107] Step 6.1: Obtain the number of critical elevations and determine the number of nodes that need to be copied.

[0108] Step 6.2: Copy the nodes on the projection plane to the corresponding elevation. Since the projection points were arranged in order in Step 5, the points in this step also follow this sorting rule. The node labels of nodes with the same X and Y coordinates differ by n × the number of projection points (where n is the number of layers between the current node and the Z=0 plane of the projection point).

[0109] Step 6.3: After the processing in step 6.2, the node numbers around any node are known. At this time, connect each node to its corresponding node at the same level and its lower level in a counterclockwise direction to form a surface geometry.

[0110] Step 6.4: Execute the loop: Determine the OBJ geometry to which the region belongs based on the coordinates of each node within the region. Then, match its corresponding physical parameters using the UUID value of the OBJ geometry. Output all information of the region according to the data structure of the .S2K file, until all regions have been traversed. At this point, the diaphragm wall is formed.

[0111] Step 7: Determine the coordinates of the supports within the foundation pit using the constitutive model attributes and UUIDs in the IFC parsing results. Obtain the node numbers of these two nodes in SAP2000 by matching the coordinates, and output the strings to the .S2K file to generate the corresponding frame unit.

[0112] Step 8: Earth pressure at each key elevation node is calculated by elevation interpolation. Once the earth pressure at all elevation nodes is obtained, it is output to an .S2K file to generate the corresponding earth pressure load.

[0113] Step 9: Use surface springs in SAP2000 to simulate soil springs. By traversing the node elevations associated with the surface area, retrieve all surface areas below the excavation surface elevation, and create and associate elevations on these surface areas.

[0114] Step 10: Number all nodes corresponding to the minimum Z-coordinate and apply fixed constraints to these nodes, i.e., calculate the required boundary conditions.

[0115] Step 11: Successfully establish the foundation pit model suitable for load-structure analysis model, generate an S2K format file and import it into SAP2000 to complete the integration of BIM-SAP2000 software.

[0116] This invention is described with reference to flowchart illustrations and / or block diagrams of methods according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0117] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the invention.

[0118] Obviously, those skilled in the art can make various modifications and variations to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if these modifications and variations to the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and variations.

Claims

1. A method for integrating BIM and SAP2000 foundation pit excavation calculations, characterized in that, include: S1: Establish a BIM parametric model and export the BIM parametric model as an IFC file. Identify and label the attributes according to the type of engineering object corresponding to the graphic element. The IFC file includes multiple graphic elements. The geometric and parameter information contained in the graphic elements is stored in the form of data blocks. The graphic elements have a corresponding relationship with the engineering objects. The types of engineering objects include foundation pit support structure, foundation pit internal support and soil. S2: Use the parsing program to parse the IFC file, identify the engineering objects corresponding to the graphic elements according to the identification attributes of the annotations, and then extract the geometric information and parameter information contained in the graphic elements. The geometric information is matched and bound with the physical parameters. The extracted geometric information and parameter information are stored as OBJ files and JSON files respectively. The geometric information includes the vertex coordinates of key geometric graphics and the topological information of the graphics. The parameter information includes physical parameters and construction parameters. S3: Based on the geometric information obtained by the analysis program, extract the coordinates of key geometric points from the foundation pit support structure and the internal support of the foundation pit, and record the key elevation information. Then, sort the extracted key geometric point coordinates. Based on the sorted nodes and key elevation information, generate the calculation elements for SAP2000 foundation pit excavation calculation, and form a format file that supports SAP2000 calculation. The key elevation information includes the elevation of the internal support of the foundation pit and the elevation of the layer interface of the foundation soil outside the foundation pit. S4: Import the format file that supports SAP2000 calculation into SAP2000 for calculation and analysis, so as to realize the integration of BIM and SAP2000 foundation pit excavation calculation; In step S2, the geometric information is matched and bound to the physical parameters, including: When the parsing program performs a parsing operation on a data block of a graphic element, it generates a universally unique identifier (UUID) and assigns it to all data in that data block. The generated UUID is transferred to both the OBJ and JSON files to achieve matching and binding between the geometric information in the OBJ file and the physical parameter information in the JSON file.

2. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 1, characterized in that, Step S1, which involves identifying and labeling attributes based on the type of the engineering object, includes: The solid structure of the foundation pit support is labeled using an elastic constitutive model, the solid structure of the support inside the foundation pit is labeled using a beam element model, and the soil is labeled using a soil constitutive model.

3. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 1, characterized in that, When S2 parses IFC files using a parsing program, it designs complete primitives as classes and the information contained within the primitives as class members. The method for extracting the geometric information contained in the primitives is as follows: The triangular element analytical function is used to parse each element in the IFC file one by one to obtain the key geometric vertex coordinates and topological information of each element in the BIM parametric model.

4. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 1, characterized in that, The method for extracting parameter information contained in primitives in S2 is as follows: The physical and construction parameters of the engineering objects corresponding to each graphic element are obtained by using the numerical analysis function of the model attribute parameters.

5. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 2, characterized in that, The key elevation information in step S3 includes the elevation of the soil layer boundary, the elevation of the support installation, and the elevation of the excavation face.

6. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 1, characterized in that, Step S3 generates calculation elements for SAP2000 foundation pit excavation calculation based on the sorted node and key elevation information, including: Based on the extracted key elevation information, the projection points on the XOY plane are copied to the corresponding elevations. All nodes are sorted and numbered. All nodes are traversed and arranged counterclockwise to generate a region. The projection points on the XOY plane are the points obtained by projecting the geometric key points onto the XOY plane. The coordinates of the support within the foundation pit are determined based on the identification attributes and UUID obtained by the parsing program. The node numbers of the two nodes in SAP2000 are obtained by coordinate matching, and the strings are output to the .S2K file to generate the corresponding frame units. Earth pressure at key elevation nodes is calculated using elevation interpolation. The surface spring in SAP2000 is used to simulate the soil spring. By traversing the elevation of the nodes associated with the surface region, all surface regions below the excavation surface elevation are retrieved, and the retrieved surface regions are associated with the corresponding elevation.

7. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 6, characterized in that, Traverse all nodes and generate a region by arranging them counter-clockwise, including: Obtain the number of critical elevations to determine the number of nodes that need to be copied; Copy the nodes on the projection plane to their corresponding elevations; Connect each node to its corresponding node at the same level and its lower level in a counterclockwise direction to form a region geometry. The OBJ geometry to which the region belongs is determined based on the coordinates of each node within the region, and the corresponding physical parameters are matched using the UUID value of the OBJ geometry. All information of the region is then output according to the data structure of the .S2K file, where the OBJ geometry corresponds to the OBJ file.

8. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 6, characterized in that, After step S2, the method further includes: organizing the information extracted from the IFC file, serializing it according to the data structure in the SAP2000 computing software, and obtaining the coordinates and node number of each node.

9. The method for integrating BIM and SAP2000 foundation pit excavation calculation as described in claim 8, characterized in that, The method further includes setting the boundary conditions required for calculation for the nodes corresponding to the nodes with the minimum Z coordinate value in the index node coordinates.

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