Coalfield geological automatic modeling and fault integration method based on IFC

Abstract

The application relates to the technical field of geological modeling, and discloses a coalfield geological automatic modeling and fault integration method based on IFC. The method firstly acquires exploration data and initializes an IFC project structure; an initial closed stratum entity with consistent interlayer topology is constructed by reusing a last layer stratum floor grid and bidirectional stretching Boolean intersection operation through a sequence constraint strategy; a space sectioning area is defined based on fault parameters, a smooth displacement transformation based on a sine weight is applied, and a stratum model containing a fault structure is generated through progressive cutting and geometric splicing; finally, entity geometry is converted into an IfcFacetedBrep form and an extended attribute set composed of geological parameters is connected, and an IFC format file is output; the application effectively solves the automatic modeling problem of interlayer gaps and complex fault structures, and realizes BIM standardized expression and cross-platform interaction of geological model geometry and attributes.

Description

Technical Field

[0001] This invention relates to the field of geological modeling technology, specifically to an automated coalfield geological modeling and fault integration method based on IFC. Background Technology

[0002] Three-dimensional geological modeling is the foundation for intelligent construction and mining engineering design in coal mines. Currently, although various professional software are widely used in the industry for geological modeling, significant technical limitations still exist in terms of data interaction, geometric topology quality, and structural processing capabilities.

[0003] First, existing geological modeling software often uses proprietary, closed data formats, leading to data barriers between various stages of geological exploration, mine design, and production management. During cross-platform transfer, format conversion often results in reduced geometric accuracy or loss of key attribute information, making it difficult to meet the needs of unified management and sharing of geological data throughout the entire mine lifecycle. Second, existing modeling techniques have shortcomings in handling stratigraphic sequence constraints. Due to the discrete nature of borehole data, traditional algorithms often struggle to ensure strict consistency of the contact surfaces when constructing the top and bottom surfaces of adjacent strata. This results in geometric gaps or mesh overlaps between generated adjacent stratigraphic entities, preventing the formation of strictly closed entities and severely impacting the accuracy of subsequent reserve calculations and finite element numerical simulations.

[0004] Furthermore, automated integration of complex geological structures such as faults remains a challenge for current technologies. Existing methods often employ simple, rigid geometric cutting when dealing with faults, lacking a continuous representation of the displacement and deformation mechanisms of the strata on both sides of the fault. This approach easily causes geometric and topological tears at fault boundaries, preventing seamless integration of fault blocks with the main strata and typically requiring significant manual post-model repair.

[0005] Therefore, this invention proposes an automated coalfield geological modeling and fault integration method based on IFC to address the shortcomings of existing technologies. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides an automated coalfield geological modeling and fault integration method based on IFC, which solves the problems of incompatible data formats, poor sequence topological consistency of stratigraphy, and difficulty in achieving automated and seamless integration of complex fault structures in existing coalfield geological modeling technologies.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an automated coalfield geological modeling and fault integration method based on IFC, comprising the following steps: S100: Acquire borehole exploration data, a unified stratigraphic sequence table for the mining area, and fault geological parameters, and initialize a project file structure that conforms to the IFC standard. S200, based on the unified stratigraphic sequence table of the mining area, the geological layers are reconstructed into three-dimensional entities layer by layer; by reusing the bottom plate mesh data of the previous layer as the top plate surface mesh of the current layer, a stratigraphic sequence constraint relationship is established; reverse vertical stretching is performed on the top plate surface mesh and bottom plate surface mesh of each layer respectively, and an initial closed stratigraphic three-dimensional entity is generated through Boolean intersection operation; S300: Define a spatial cutting region based on the fault geological parameters; use the fault plane equation to geometrically segment the initial closed strata three-dimensional entities intersecting the spatial cutting region; classify the hanging wall and footwall vertices of the segmented grid according to the fault geometric elements, and apply a smooth displacement transformation based on spatial position weights; reconstruct the fault surface and generate fault structural blocks; and geometrically merge the fault structural blocks with the main strata entities unaffected by the fault. S400 converts the generated geometric data of the closed stratum 3D entity and fault structure block into the planar boundary representation in the IFC standard, defines a geological-specific extended attribute set, associates the geological-specific extended attribute set with the corresponding entity object, and outputs a coalfield geological model file in IFC format.

[0008] Preferably, in step S100, the process of establishing the unified stratigraphic sequence table for the mining area includes: establishing an ordered set containing all stratigraphic elements, defining a globally unique index, standard stratigraphic name, lithological category, and physical property parameter set for each stratigraphic element in the ordered set; the physical property parameter set includes at least density, permeability, and porosity; and using the unified stratigraphic sequence table for the mining area as a reference benchmark to check whether there are stratigraphic missing or inverted anomalies in the borehole exploration data.

[0009] Preferably, in step S200, establishing the stratigraphic sequence constraint relationship specifically includes: for the first stratum in the stratigraphic sequence, generating the top surface mesh of the first stratum based on the control point data in the borehole exploration data using the Delaunay triangulation algorithm; for any i-th stratum in the stratigraphic sequence located after the first stratum, directly inheriting the vertex data structure and topological connection relationship of the bottom surface mesh of the (i-1)-th stratum as the top surface mesh of the i-th stratum, so that the top of the i-th stratum coincides with the bottom of the (i-1)-th stratum in geometric space.

[0010] Preferably, in step S200, generating the initial closed stratum 3D entity specifically includes: obtaining the top surface mesh of the current stratum, projecting and translating all vertices of the top surface mesh along the gravity direction by a preset stretching threshold to construct a downward stretching body; obtaining the bottom surface mesh of the current stratum, projecting and translating all vertices of the bottom surface mesh along the anti-gravity direction by the stretching threshold to construct an upward stretching body; performing a Boolean intersection operation to construct the entity geometry on the downward stretching body and the upward stretching body, retaining the common space region located below the top surface mesh and simultaneously above the bottom surface mesh, to generate a closed stratum 3D entity that satisfies the manifold property.

[0011] Preferably, in step S300, the geometric segmentation specifically includes: constructing a three-dimensional closed geometry as the spatial cutting region; calculating the Boolean intersection of the initial closed stratum three-dimensional entity and the spatial cutting region to obtain the stratum block to be processed; calculating the Boolean difference between the initial closed stratum three-dimensional entity and the spatial cutting region to obtain the main stratum block that retains the original sedimentary morphology; and using the analyzed fault geological parameters to construct a point-normal plane equation to further segment the stratum block to be processed into the hanging wall region and the footwall region.

[0012] Preferably, in step S300, the classification of the hanging wall and footwall specifically includes: calculating the unit normal vector of the fault plane based on the strike angle and dip angle in the fault geological parameters; calculating the directed Euclidean distance from any grid vertex in the stratigraphic block to the fault plane; and dividing the grid vertices into a hanging wall point set and a footwall point set according to the positive or negative sign of the directed Euclidean distance.

[0013] Preferably, in step S300, applying a smooth displacement transformation based on spatial location weights specifically includes: calculating the basis vector of sliding along the maximum dip direction of the fault plane, and calculating the theoretical maximum rigid displacement vectors of the hanging wall and footwall in combination with the fault displacement in the fault geological parameters; introducing normalized location parameters and a sinusoidal attenuation weight function, wherein the sinusoidal attenuation weight function takes the maximum value at the fault plane position and attenuates to zero at the boundary of the spatial cutting area; applying a nonlinear displacement transformation to the vertex coordinates of the hanging wall point set and the footwall point set using the sinusoidal attenuation weight function, so that the geometric deformation caused by the fault is maximized near the fault plane and gradually and smoothly attenuates towards the two side boundaries.

[0014] Preferably, in step S300, the generation of fault structure blocks and geometric assembly specifically includes: obtaining the point set after the smooth displacement transformation; reconstructing the top and bottom surfaces of the hanging wall and footwall using the Kriging interpolation algorithm and the constrained Delaunay triangulation algorithm with fault traces as constraint edges; using a progressive cutting method, first using the fault plane to cut the initial tensile body to generate an intermediate body, and then using the reconstructed top and bottom surfaces to trim the intermediate body to generate independent fault structure blocks; performing a Boolean union operation on the main stratigraphic block and the generated fault structure block to merge them into a stratigraphic model containing fault structures.

[0015] Preferably, in step S400, the conversion to the planar boundary representation in the IFC standard specifically includes: extracting the triangular mesh data of the closed stratum 3D entity and fault structure block; instantiating the mesh vertices as IfcCartesianPoint Cartesian point objects, constructing IfcPolyLoop polygon loop objects using triangular facet vertex references, and then constructing IfcFace face objects; aggregating all IfcFace face objects into IfcClosedShell closed shell containers and encapsulating them as IfcFacetedBrep entity types; creating IfcBuildingElementProxy entities or IfcGeotechnicalElement entities as semantic containers to carry IfcFacetedBrep entity types, and establishing a spatial hierarchy mapping relationship from IfcProject project nodes to IfcSite site nodes and then to semantic containers.

[0016] Preferably, in step S400, defining the geological-specific extended attribute set includes: constructing a stratigraphic basic information attribute set, which includes stratigraphic sequence number, lithological name, and geological age attribute items; constructing a physical attribute set, which includes volumetric density, permeability, and porosity attribute items; constructing a fault structural parameter attribute set, which includes fault unique number, fault property, fault displacement, and fault dip attribute items; and creating an IfcRelDefinesByProperties relation entity to bidirectionally bind the geological-specific extended attribute set, filled with specific values, to the corresponding geological entity object.

[0017] This invention provides an automated coalfield geological modeling and fault integration method based on IFC (Integrated Fault Control). It has the following beneficial effects: 1. This invention effectively solves the common problems of interlayer gaps and overlaps in multi-layer geological body modeling by establishing a sequence constraint mechanism based on mesh inheritance. The method forcibly calls the bottom plate mesh data of the previous stratum as the top plate surface mesh of the current stratum, ensuring the geometric topological consistency of the contact surface between adjacent strata from the data source. Combined with bidirectional vertical stretching and Boolean intersection operations, it can automatically generate closed three-dimensional entities that satisfy manifold properties, ensuring the rigor of the geological model in terms of geometric structure, avoiding the topological errors caused by traditional independent interpolation modeling, and providing a high-quality geometric foundation for subsequent volume calculations and numerical simulations.

[0018] 2. This invention proposes a parameterized fault integration strategy based on spatial location weights, achieving seamless integration of fault structures and stratigraphic entities. By defining the fault spatial cutting region and applying a smooth attenuation displacement field based on a sine function, this method maximizes the displacement of the stratigraphic mesh near the fault plane and gradually transitions smoothly to zero towards the boundary of the affected area. This nonlinear displacement transformation method overcomes the problems of model edge tearing or geometric non-closure caused by the movement of traditional rigid fault blocks. It can accurately express the fault's drop and spatial attitude while maintaining the stability of the main stratigraphic structure, thus improving the realism and automated processing capability of complex geological structure models.

[0019] 3. This invention establishes a mapping system between geological entities and the IFC-4.3 international standard, breaking down data barriers between geological modeling and BIM engineering applications. By converting the geometry of geological bodies into an IfcFacetedBrep planar boundary representation and defining a dedicated extended attribute set that includes lithology, density, and fault parameters, the generated coalfield geological model possesses universal semantic interoperability. The generated IFC format file can be directly read and parsed by various BIM design software and mining professional software without format conversion, supporting the lossless transfer of geometric and attribute information and promoting cross-platform sharing and application of mine geological exploration data throughout the entire lifecycle of engineering design, construction, and operation and maintenance. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the method flow of the present invention; Figure 2 This is a schematic diagram of the system architecture of the present invention. Detailed Implementation

[0021] The technical solutions in 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, and 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.

[0022] See attached document Figure 1 This method is mainly executed collaboratively by a data input module, a sequence constraint modeling module, a fault integration module, and an IFC generation module, specifically including: The data input module acquires borehole exploration data, a unified stratigraphic sequence table for the mining area, and fault geological parameters. The borehole exploration data includes the geographic coordinates of the borehole opening and the top and bottom depth data of different layers inside each borehole. The unified stratigraphic sequence table for the mining area defines the sedimentary sequence of geological layers from top to bottom, the standard stratigraphic position number, and the corresponding lithological and physical properties within the target area. The fault geological parameters include the spatial geometric elements of the fault, including strike angle, dip angle, dip vector, and displacement value. The data input module also initializes a project file structure conforming to the IFC4.3 standard and establishes the project root node and site node.

[0023] The sequence constraint modeling module reconstructs the geological layers into three-dimensional entities layer by layer based on the unified stratigraphic sequence table of the mining area. For the first stratum in the stratigraphic sequence, the module generates the top surface mesh using the Delaunay triangulation algorithm based on the borehole control point data of that layer. For any i-th stratum after the first layer in the stratigraphic sequence, the module forcibly calls the bottom mesh data of the (i-1)-th stratum as the top surface mesh of the i-th stratum, ensuring the topological consistency of the interface between adjacent strata through data reuse. The module performs a downward vertical stretching operation on the top surface mesh of each layer and an upward vertical stretching operation on the bottom surface mesh, constructing stretching bodies respectively. The module then calculates the common part of the two stretching bodies through Boolean intersection operation to generate the initial closed 3D stratum entity.

[0024] The fault integration module reads fault geological parameters and defines a spatial cutting region surrounding the fault in three-dimensional space. It identifies initial 3D stratigraphic entities that geometrically intersect this spatial cutting region and uses fault plane equations to geometrically segment the affected entities, dividing them into areas to be processed and areas to be preserved. Based on the geometric definitions of the hanging wall and footwall of the fault plane, the module classifies the mesh vertices within the area to be processed. It calculates the slip vector based on the fault type and displacement, and applies displacement transformations to the vertex coordinates of the hanging wall and footwall regions using a spatial position weighting function. The module reconstructs the fault surface using Kriging interpolation and constrained triangulation algorithms, and generates independent fault structure blocks containing the hanging wall entity, footwall entity, and fault plane using a progressive cutting method. Finally, the module geometrically merges the generated fault structure blocks with the main stratigraphic entities of the preserved areas to form a stratigraphic model containing fault structures.

[0025] The IFC generation module traverses all generated closed 3D strata entities and fault structures, converting their geometric data into the IfcFacetedBrep planar boundary representation in the IFC standard. The IFC generation module establishes a spatial hierarchy mapping from IfcProject to IfcSite and then to IfcBuildingElementProxy. The IFC generation module defines an IFC attribute set containing lithological descriptions, density, permeability, and fault geometric parameters, and associates this attribute set with the corresponding 3D entity objects, ultimately outputting a coalfield geological model file conforming to the IFC standard.

[0026] See attached document Figure 2 This invention provides an automated coalfield geological modeling and fault integration method based on IFC, comprising the following steps: S100, the data input module acquires borehole exploration data, a unified stratigraphic sequence table for the mining area, and fault geological parameters, and initializes the IFC project file structure; S200, the sequence constraint modeling module, based on the unified stratigraphic sequence table of the mining area, uses the sequence constraint strategy of reusing the bottom plate mesh of the previous layer as the top plate mesh of the current layer, and uses bidirectional stretching Boolean intersection operation to generate the initial closed three-dimensional entity of each geological layer. S300, the fault integration module defines a spatial cutting area based on fault geological parameters, segments the affected strata, calculates and applies the slip displacement of the hanging wall and footwall, reconstructs the fault surface and generates fault structural blocks, and combines them with the unaffected main strata entity; S400, the IFC generation module converts the generated stratigraphic entities and fault structures into IFC standard geometric representations, associates them with a predefined set of geological attributes, and outputs IFC format geological model files.

[0027] The specific implementation methods of the above steps will be described in detail below with reference to the accompanying drawings.

[0028] See attached document Figure 2 The data preprocessing step S100 performed by the data input module specifically includes the following steps: S110, Establish a structured mapping of borehole exploration data; The data input module reads the original borehole records stored in unstructured files or databases and parses them into a standardized borehole dataset. ,in, This represents the total number of boreholes; for any single borehole... It is defined to include the spatial coordinate information of the orifice. And a stratigraphic information list; the stratigraphic information list consists of several stratigraphic interval data units, each data unit containing stratigraphic name identifier and top depth. , bottom depth And the corresponding lithological description; in this process, if the coordinate system of the original data is inconsistent with the target modeling coordinate system, the coordinates of all borehole openings need to be uniformly transformed to the project engineering coordinate system through the coordinate transformation matrix.

[0029] S120, Constructing a unified stratigraphic sequence table for the mining area This sequence list is used to define the stratigraphic sedimentary sequence and physical property standards for the entire modeling area; the data input module establishes an ordered set. ,in, The total number of strata, subscript Represents the stratigraphic sequence index from top to bottom; for each stratigraphic element in the set The association defines its globally unique index. Standard stratigraphic name, lithological category, standard color value and a set of physical property parameters; the set of physical property parameters must include at least density. Penetration rate and porosity This unified stratigraphic sequence table serves as the sole reference for subsequent sequence constraint modeling and is used to verify stratigraphic missing or inverted anomalies in borehole data.

[0030] S130, analyze and quantify fault geological parameters; the data input module reads the fault parameter table for each fault. Analyze its geometric elements and kinematic parameters; geometric elements include the fault strike angle. (Angle of rotation clockwise from true north), Inclination (The angle between the fault plane and the horizontal plane) and the coordinates of the fault center point Kinematic parameters include fault elevation. And fault type identification; based on the resolved angle parameters, calculate the fault dip unit vector. ,in, On a horizontal plane, it is typically 0; for fault type identification, a coefficient is set. When its value is 1, it indicates a normal fault; when it is -1, it indicates a reverse fault; and when it is 0, it indicates a strike-slip fault.

[0031] S140, Initialize the IFC project environment; the data input module calls the IFC engine interface to create a project instance file conforming to the IFC 4.3 architecture standard; in this instance, first, the IfcProject entity is created as the root node and assigned a globally unique identifier; then, the IfcUnitAssignment entity is created, setting the length unit to meters and the angle unit to degrees to ensure dimensional consistency in subsequent geometric operations; next, the IfcGeometricRepresentationContext entity is created, defining the coordinate space dimension of the 3D geometric modeling as 3 and the precision tolerance as 10. 5 Meters are used to support high-precision Boolean operations. Finally, an IfcSite entity is created under IfcProject to map the actual mining area's geographical site, serving as a spatial container for all subsequent geological entity objects; metadata information in the IFC file header, such as author, organization, and generation time, is automatically populated in this step.

[0032] See attached document Figure 2 In the sequence-constrained stratigraphic modeling step S200 executed by the sequence-constrained modeling module, considering the discreteness of stratigraphic data and the continuity of geological sequences, the following steps are specifically included: S210 performs the extraction and standardization of layered geological point cloud data; the sequence constraint modeling module is based on a pre-constructed unified stratigraphic sequence table for the mining area. Traverse the stratigraphic index in top-down order ( ); for the currently processed first The stratigraphic sequence constraint modeling module traverses the borehole dataset. Each drill hole If drilling There exists a first Record the stratigraphic layers to read the burial depth of the top plate of that layer. and the depth of the base plate Combined with borehole coordinates Calculate the spatial position of the control point in the absolute coordinate system.

[0033] Top plate control point set Defined as: ; Base plate control point set Defined as: ; During this process, the sequence constraint modeling module removes invalid data points and organizes all extracted 3D coordinate points into a format that facilitates geometric calculations. Floating-point matrix structure.

[0034] S220, construct a sequence-constrained surface based on mesh inheritance; the sequence-constrained modeling module uses a triangulation algorithm to reconstruct discrete point cloud data into a continuous triangular mesh surface; this step ensures the geometric consistency of the contact surface between adjacent strata through mandatory topological inheritance logic.

[0035] For the first stratum in the stratigraphic sequence (i.e. ): The sequence constraint modeling module obtains the control point set of the first floor roof slab. The points are projected onto the XY plane; the Delaunay triangulation algorithm is performed on the projected point set on the two-dimensional plane to construct triangular topological relationships; the vertex indices of the triangulated triangles are mapped back to three-dimensional spatial coordinates to generate the surface mesh of the first-layer top plate. The surface mesh consists of a vertex set. Dough Piece Index Set constitute.

[0036] For any th layer in the stratigraphic sequence that is after the first layer Layers (i.e.) ): The sequence constraint modeling module performs sequence constraint operations, but does not directly use the first sequence constraint. Top slab control point set of the layer Instead of performing independent interpolation or partitioning, it directly inherits from the previous stratum (the first stratum). The bottom surface mesh data of the current layer is used as the top surface mesh of the current layer; the constraint relationship is expressed as: ; In specific implementation, the hierarchical constraint modeling module will... The vertex data structure and topological connectivity of the bottom layer surface are directly copied into memory or referenced to the first layer. The top panel object makes: ; ; This operation ensures that the first The top slab of the first floor and the second floor The base plates of the layers are mathematically identical, and the normal distance between them is zero at any position, that is: ; This eliminates the interlayer gaps or interlayer overlaps commonly found in traditional independent interpolation methods at the geometric topology level.

[0037] For each stratum (including) to ) Base plate surface construction: The sequence constraint modeling module obtains the control point set of the current layer's bottom plate. In the XY plane projection space, the same Delaunay triangulation algorithm used for generating the top plate, or a constraint-boundary-based triangulation algorithm, is employed to generate the mesh for the bottom plate surface. The generated base plate surface mesh contains a vertex set. Dough Piece Index Set This mesh will serve as the geometric basis for generating the bottom surface of the current layer and the top surface of the next layer. Through the above iterative process, the set of top and bottom surfaces of all geological layers is generated, and this set satisfies the seamless interlayer connection constraint of the entire sequence.

[0038] The stratigraphic constraint modeling module completes the meshing of the top surface of each geological layer. and base plate surface grid After the initial construction, step S230 is executed, which is the closed solid generation step based on Boolean intersection operation. This step aims to solve the topological problem of generating sidewalls between irregular curved surfaces and automatically construct a closed 3D solid that satisfies the manifold property. Specifically, it includes the following steps: S231, Construct a downwardly stretched body; the sequence constraint modeling module first calculates the current strata. Maximum bounding box height range or preset stretch threshold The stretch threshold The thickness must be greater than the maximum possible thickness of the strata within the current modeling area to ensure the validity of subsequent Boolean operations; the sequence constraint modeling module obtains the top surface mesh. The coordinates of all vertices are projected and translated along the negative Z-axis (i.e., the direction of gravity) by a distance of . The sequence constraint modeling module stitches the boundary edges of the original top surface with the corresponding translated boundary edges using quadrilateral meshes, closing the sides to generate a closed polyhedron with downward semi-infinite spatial properties, defined as a downwardly stretched body. The geometric meaning of this entity represents all potential spatial regions located beneath the top of the strata.

[0039] S232, Construct an upwardly stretched body; the sequence constraint modeling module obtains the mesh of the base plate surface. The coordinates of all vertices are projected and translated along the positive Z-axis (i.e., the anti-gravity direction), with the translation distance also set to 1. The sequence constraint modeling module utilizes the same side stitching logic as S231 to connect the original base plate surface with the surface after upward translation, constructing a closed polyhedron with upward semi-infinite spatial properties, defined as an upwardly stretched body. The geometric meaning of this entity represents all potential spatial regions located above the stratum floor.

[0040] S233, Perform Boolean intersection operation to generate the final stratigraphic entity; the sequence constraint modeling module applies the downwardly stretched body... and upward stretching body Perform the Boolean intersection operation in the constructed solid geometry; the mathematical model is represented as follows: ; in, Indicates the generated first Layered geological entities, This represents the Boolean intersection operator; through this operation, the system automatically preserves the common space area located below the top plate and simultaneously above the bottom plate.

[0041] S234, Topological integrity verification and normal unification; in this process, since the sidewalls generated by the downward stretching of the top plate and the upward stretching of the bottom plate are completely coincident in the horizontal projection, the Boolean intersection operation can automatically generate the vertical side boundary connecting the top and bottom plates, without the need for manual side stitching or repair; the sequence constraint modeling module performs modeling on the generated entities. Water tightness testing is performed to ensure that the normal vectors of all triangular facets point uniformly outward from the solid and that there are no non-manifold edges or holes. For solids that pass the test, they are marked as valid stratigraphic geometric objects and used as the input basis for subsequent fault integration. This Boolean intersection-based generation method can effectively handle the complex situation where the projections of the top and bottom plates are not completely consistent, and avoids the generation of self-intersecting meshes, compared with the traditional direct stitching side edge method.

[0042] In the fault structure integration step S300 executed by the fault integration module, the following sub-steps are specifically included to address the complex spatial geometric features of the geological body's fault structure: S310, Define the fault-affected area and perform local stratigraphic segmentation; the fault integration module constructs a three-dimensional closed geometry (including but not limited to an axis-aligned cuboid defined by parametric equations, a column formed by stretching the boundary of any closed polygon along the vertical direction, or other irregular three-dimensional closed bodies) as the fault-affected area based on the fault distribution range provided by geological exploration. The area The boundary forms the interface between the fault disturbance zone and the background stratigraphic zone; the fault integration module traverses every stratigraphic entity in the initial stratigraphic model set. It performs Boolean partitioning operations based on the constructed entity geometry. First, it calculates the stratigraphic entity. and the area of ​​impact The Boolean intersection yields the stratigraphic blocks located within the fault's influence area that require geometric reconstruction. Simultaneously, calculate the stratigraphic entity. and the area of ​​impact The Boolean difference set yields the main stratigraphic block located outside the fault's influence area and retaining its original sedimentary morphology. This step transforms the overall modeling problem into a local structural reconstruction problem, ensuring the absolute stability of data in non-fault areas and providing geometric constraints for the seamless integration of fault blocks with the main strata.

[0043] S320 analyzes fault plane parameters and classifies stratigraphic grid points; the fault integration module is based on the input fault strike angle. ,inclination and tendency vector (in (Usually set to 0), calculate the unit normal vector of the fault plane. The formula for calculating the normal vector is defined as follows: ; The normal vector determines the spatial orientation of the fault plane; the fault integration module obtains the fault center location point. Establish the point-normal fault plane equation: Subsequently, the fault integration module extracts the stratigraphic blocks to be processed. All grid vertices, for any vertex Calculate its directed Euclidean distance to the fault plane. : ; Based on the sign of the directed distance, the fault integration module divides the mesh vertices into upper disk point sets. and the next set of scores ; definition if Then the vertex It belongs to the upper plate; if Then the vertex It belongs to the lower plate; this classification process lays the data foundation for subsequent differential application of tectonic displacement.

[0044] S330, Calculate the smoothed attenuation displacement field based on a sinusoidal weighting function; this step aims to resolve the relationship between the displacement of the fault block and the unmoved main stratum block. To address the geometric tearing problem between fault planes and achieve a smooth spatial transition of displacement, the fault integration module first calculates the basis vectors of sliding along the fault plane. This vector indicates the unit direction of the formation's slip along the direction of maximum dip: ; Next, combined with the fault elevation difference With fault type coefficient (Take normal faults as 1, reverse faults as -1), calculate the theoretical maximum rigid displacement vector between the hanging wall and footwall; total slip distance. It is derived from the geometric relationship between elevation difference and inclination angle, that is... Upper plate displacement vector With the lower displacement vector They are defined as follows: ; ; To ensure the displacement continuity between the fault block edge and the main stratigraphic block edge, the fault integration module introduces normalized position parameters. and sinusoidal decay weighting function For the affected area any point within, defined It is the normalized mapping value of the area from one boundary of the affected region across the fault plane to the other boundary, where and Corresponding area boundary, Corresponding fault plane location; the weighting function is defined as: ; This function is at the fault plane ( The value is 1, corresponding to the maximum displacement; at the boundary ( A value of 0 corresponds to zero displacement; the fault integration module uses this weighting function to assign coordinates to all vertices of the hanging wall and footwall. Apply nonlinear displacement transformation to generate deformed coordinates : ; Through this smooth attenuation model, the geometric deformation caused by the fault is mainly concentrated near the fault plane and gradually attenuates to zero towards the two sides, thus ensuring... It can still be deformed By keeping the boundaries closed, the model breakage caused by traditional rigid movement is avoided.

[0045] In the fault structure integration step S300 executed by the fault integration module, after the displacement field calculation is completed, the surface reconstruction and solid cutting sub-steps are executed. This process uses a specific progressive Boolean operation sequence to solve the complex geometric topology closure problem caused by fault displacement, and specifically includes the following process: S340, perform fault surface reconstruction based on the variation function; the fault integration module obtains the upper plate point set after smooth displacement field transformation. and the next set of scores Because the displacement transformation distorts the topology of the original mesh, the fault integration module needs to reconstruct a continuous geometric surface. To address the spatial correlation of geological variables, the fault integration module employs a spherical model as the variation function in a Kriging interpolation algorithm to perform high-precision reconstruction of the top and bottom plates of the hanging wall and footwall respectively. (Spherical model function...) The definition is as follows: ; in, Indicates the lag distance between sample points. This indicates the nugget value, representing micro-variation or measurement error; The arch height represents the magnitude of structural variation; The variable range represents the maximum extent of spatial correlation. A dense grid is generated using this interpolation algorithm. Subsequently, the fault integration module employs the constrained Delaunay triangulation (CDT) algorithm to generate a new upper plate surface. Surface of the upper plate bottom and the corresponding lower plate surface and During this segmentation process, the fault integration module sets the traces of the fault plane as forced constraint edges to ensure that the reconstructed surface precisely matches the geometric features of the fault plane at the fault boundary, preventing the formation of cracks.

[0046] S350 performs progressive fault block cutting; to avoid non-manifold geometric errors or Boolean operation failures that may occur when directly generating solids using complex surfaces, the fault integration module generates fault structure blocks in a specific order of "stretching first, then cutting, and then trimming".

[0047] First, construct the initial stretched body. The fault integration module generates a map covering the area affected by the fault. Furthermore, rectangular or convex solids with heights far exceeding the thickness of the strata are used as raw materials for geometric processing.

[0048] Secondly, the initial tensile body is cut using the fault plane; the fault integration module utilizes the fault plane equation defined in step S320. For the initial stretched body Perform a Boolean split operation; this operation will It splits into two along the fault plane, forming an intermediate body located on the hanging wall side. and the intermediate body located on the lower side This step ensures that the generated solid sidewalls fit perfectly against the fracture surface.

[0049] Finally, the intermediate body is trimmed using the reconstructed surface; the fault integration module utilizes the reconstructed upper plate surface. As the upper cutting surface, the surface of the upper plate bottom plate As the lower cutting surface, for Perform Boolean difference or intersection trimming operations to remove excess volume located above the top plate and below the bottom plate, thereby obtaining the final shape of the hanging wall fault block. Similarly, the surface of the bottom plate of the lower plate is used to... Trimming was performed to obtain the footwall fault block. This progressive strategy ensures that the generated fault blocks are geometrically strictly closed and topologically correct through step-by-step constraints.

[0050] S360: Perform geometric integration of fault structures with the main stratigraphy; after generating independent fault blocks, the fault integration module merges the updated structures back into the original stratigraphic model; the fault integration module performs a Boolean union operation, retaining the main stratigraphic blocks... Newly formed hanging wall fault block and the newly formed footwall fault block Merged into a single geometric object; the merged stratigraphic entity Expressed as: ; In cases where multiple faults exist, the fault integration module will integrate the current faults. As input for the next round of processing, read the next fault parameters. Repeat steps S310 to S360 until all faults are integrated into the model. Through this iterative mechanism, the system can automatically handle complex geological structures such as multiple fault intersections and finally output a refined stratigraphic model containing complete fault information.

[0051] In the IFC standard model generation step S400 executed by the IFC generation module, the aim is to transform the calculated heterogeneous geological geometric data into BIM standard data with semantic interoperability, specifically including the following sub-steps: S410, perform IFC geometric representation transformation of geological entities; the IFC generation module traverses the final set of stratigraphic entities and fault structure blocks generated in step S300; for any 3D geological entity object, the IFC generation module first extracts its triangular mesh data, which consists of a vertex coordinate list and a facet index list; the IFC generation module performs geometric reconstruction using boundary representation (B-Rep) according to the data definition of the IFC 4.3 standard; specifically, the IFC generation module instantiates each vertex coordinate (x, y, z) in the mesh as an IfcCartesianPoint object; for each triangular facet... The IfcPolyLoop object is constructed using references to its three vertices, defining the closed face boundary. Subsequently, an IfcFace object is constructed based on the IfcPolyLoop, and all IfcFace objects contained in the entity are aggregated into the IfcClosedShell container to form a closed shell structure. Finally, the IfcClosedShell is encapsulated into the IfcFacetedBrep entity type. This type is specifically designed to express a closed shell enclosed by planar polygons, which can accurately support complex geological surfaces generated by Delaunay triangulation and meet the manifold consistency requirements of geometric topology.

[0052] S420 constructs the IFC spatial hierarchy mapping; the IFC generation module establishes a strict tree-like containment relationship based on the spatial decomposition specifications of the industrial basic class standard; the IFC generation module creates IfcBuildingElementProxy or IfcGeotechnicalElement entity instances as semantic containers for geological entities, used to carry the generated IfcFacetedBrep geometric expressions; the IFC generation module associates the IfcBuildingElementProxy instance representing the geological entity with the IfcSite node through the IfcRelContainedInSpatialStructure relation entity, establishing the spatial membership relationship between the geological body and the mining area site, thereby constructing a three-level spatial topology structure of "Project (IfcProject), Site (IfcSite), Geological Entity (IfcBuildingElementProxy)".

[0053] S430 defines a geologically specific extended attribute set; to address the lack of dedicated semantic descriptions for coalfield geological features in the standard IFC system, the IFC generation module constructs a custom attribute set template in memory; this template contains three independent attribute set definitions: First, construct the basic stratigraphic information attribute set Pset_LayerBasicInfo; this attribute set contains the following attribute items: LayerIndex: Type IfcInteger, stores the stratigraphic sequence number of the stratum. Used to identify the depositional sequence of strata; Lithology: of type IfcLabel, stores the lithological names of strata (such as sandstone, mudstone), corresponding to the descriptions in the unified stratigraphic sequence table; GeologicAge: of type IfcLabel, stores geological age information; Color_RGB: Type IfcLabel, stores the RGB value string of the color (formatted as (R, G, B)), used in visualization software to render and distinguish different geological layers.

[0054] Second, construct the physical property information attribute set Pset_PhysicalProperties; this attribute set contains the following attribute items: MassDensity: Type IfcMassDensityMeasure, stores the volume density ρ of the formation unit, in kg / m³. 3 ; Permeability: Type IfcReal, storage penetration coefficient. For subsequent hydrogeological analysis; Porosity: Type IfcNormalisedRatioMeasure, stores porosity. The value ranges from 0 to 1.

[0055] Third, construct the fault structural parameter attribute set Pset_FaultParameters. This attribute set is defined only for entities identified as fault structural blocks and includes the following attribute items: Fault-ID: Type IfcIdentifier, stores a unique number for the fault; Fault-Type: The type is IfcLabel, which stores the fault nature (normal fault / reverse fault). Throw-Distance: Type IfcLengthMeasure, stores the fault drop. ; Dip-Angle: Type IfcPlaneAngleMeasure, stores fault dip angle. .

[0056] In step S440, the semantic binding of attribute sets and entities is performed. The IFC generation module instantiates an IfcPropertySet object and fills the corresponding attribute set template with the specific attribute values ​​defined in step S430. Subsequently, the IFC generation module creates an IfcRelDefinesByProperties relation entity and performs a two-way binding between the populated IfcPropertySet instance and the corresponding IfcBuildingElementProxy geological entity instance. Through this binding operation, the geometric model and non-geometric geological semantic information are integrated at the data level. Finally, the IFC generation module serializes all constructed objects into the STEP physical file format (.ifc), outputting a BIM model file containing complete geometric topology and geological attributes. This file can be directly read by general BIM software or mining design software, realizing cross-platform interaction and full lifecycle application of geological modeling results.

[0057] This embodiment selects exploration data from the northern wing mining area of ​​an actual coal mine as the input object. Through specific data parameter settings and process execution, the effectiveness and topological integrity of the method proposed in this invention are verified.

[0058] The implementation example establishes the background and input data parameters. This example selects 24 control boreholes numbered ZK01 to ZK24 within the mining area as the initial input. The stratigraphic sequence is set as a four-layer standard stratigraphic structure, from top to bottom: Quaternary topsoil (sequence index k=1), coarse sandstone aquifer (sequence index k=2), No. 3 coal seam (sequence index k=3), and silty mudstone floor (sequence index k=4). The input fault parameters correspond to the F5 normal fault in this area, with the following geological parameters: fault strike angle of 45 degrees, dip direction southeast, fault dip angle of 60 degrees, fault displacement of 15 meters, and fault center point coordinates located at the geometric center of the mining area. The data input module parses the above borehole coordinate data and stratigraphic layer thickness data into a three-dimensional scatter cloud matrix and converts the fault parameters into unit normal vectors and sliding basis vectors.

[0059] Key process parameters were set and intermediate sequence geological bodies were generated. In the sequence constraint modeling stage, the horizontal grid interpolation accuracy was set to 10 m × 10 m, the kriging interpolation range parameter was set to 500 m, and the nugget value was 0. To ensure the effectiveness of the Boolean intersection operation, the vertical stretching threshold was set to 300 m. The sequence constraint modeling module first constructed the top surface grid of the Quaternary topsoil. When constructing the coarse sandstone aquifer (k=2), the bottom grid data of the Quaternary topsoil was directly called as the top grid of the coarse sandstone aquifer, ensuring zero-error fit of the contact surface between the two in geometric space. Subsequently, downward and upward stretching bodies of each layer were generated and Boolean intersection operation was performed. Intermediate results showed that the four initial stratigraphic entities generated maintained strict layered sedimentary relationships in areas undisturbed by faults, and there were no gaps or overlaps between adjacent strata.

[0060] Fault integration and smooth displacement processing were performed. The fault integration module defined a rectangular space with a width of 100 meters as the influence area of ​​the F5 fault. For the No. 3 coal seam entity located within this area, the fault integration module used the point-normal plane equation to divide it into the hanging wall block and the footwall block to be processed. Based on the sinusoidal decay weight function, a downward slip component along the dip direction was applied to the grid vertices of the hanging wall, and an upward slip component along the dip direction was applied to the grid vertices of the footwall. The slip amount reached a maximum of 7.5 meters (half of the total drop) at the fault plane and decayed to 0 at the boundary. During the surface reconstruction process, the constrained Delaunay triangulation algorithm was used to repair the grid distortion caused by displacement. Finally, through progressive cutting and splicing, a composite geological model containing the structural features of the F5 fault was generated.

[0061] The final model is output and its topological integrity is verified. The IFC generation module converts the above geometric objects into IfcFacetedBrep entities and attaches an extended attribute set containing lithology (e.g., "No. 3 coal"), density (e.g., 1.35 tons / cubic meter), and fault drop (15 meters). The system finally outputs a STEP format file conforming to the IFC-4.3 standard. The output file is parsed and geometrically checked using a standard BIM model checking tool. The results show that the eight generated geological entity objects (including fault fracture zone blocks) are all manifold geometries, their Euler indices conform to the characteristics of a closed shell, all triangular facets have outward normals, and there are no non-manifold edges or exposed edges. At the same time, in the IFC viewer, the attribute information of each geological body is complete, and the spatial hierarchy is correctly displayed as "Project, Site, Geological Entity", verifying the feasibility of this method in actual complex geological modeling and the reliability of its data interaction capabilities.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for automated coalfield geological modeling and fault integration based on IFC, characterized in that, Includes the following steps: S100: Acquire borehole exploration data, a unified stratigraphic sequence table for the mining area, and fault geological parameters, and initialize a project file structure that conforms to the IFC standard. S200, based on the unified stratigraphic sequence table of the mining area, the geological layers are reconstructed into three-dimensional entities layer by layer; by reusing the bottom plate mesh data of the previous layer as the top plate surface mesh of the current layer, a stratigraphic sequence constraint relationship is established; reverse vertical stretching is performed on the top plate surface mesh and bottom plate surface mesh of each layer respectively, and an initial closed stratigraphic three-dimensional entity is generated through Boolean intersection operation; S300, define a spatial cutting region based on the fault geological parameters, and use the fault plane equation to geometrically segment the initial closed three-dimensional strata that intersect with the spatial cutting region; classify the hanging wall and footwall of the segmented mesh vertices according to the fault geometric elements, and apply a smooth displacement transformation based on spatial position weights. The fault surface is reconstructed and fault structure blocks are generated. The fault structure blocks are then geometrically assembled with the main stratigraphic entities that are not affected by the fault. S400 converts the generated geometric data of the closed stratum 3D entity and fault structure block into the planar boundary representation in the IFC standard, defines a geological-specific extended attribute set, associates the geological-specific extended attribute set with the corresponding entity object, and outputs a coalfield geological model file in IFC format.

2. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 1, characterized in that, In step S100, the process of establishing the unified stratigraphic sequence table for the mining area includes: Establish an ordered set containing all stratigraphic elements, and define a globally unique index, standard stratigraphic name, lithological category, and physical property parameter set for each stratigraphic element in the ordered set; The set of physical property parameters includes at least density, permeability, and porosity; The unified stratigraphic sequence table of the mining area serves as a reference for verifying whether there are any missing or inverted stratigraphic sequences in the borehole exploration data.

3. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 1, characterized in that, In step S200, establishing the hierarchical constraint relationship specifically includes: For the first stratum in the stratigraphic sequence, the Delaunay triangulation algorithm is used to generate the surface mesh of the top plate of the first stratum based on the control point data in the borehole exploration data. For any i-th stratum located after the first stratum in the stratigraphic sequence, the vertex data structure and topological connection relationship of the bottom surface mesh of the (i-1)-th stratum are directly inherited as the top surface mesh of the i-th stratum, so that the top plate of the i-th stratum coincides with the bottom plate of the (i-1)-th stratum in geometric space.

4. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 3, characterized in that, In step S200, generating the initial closed three-dimensional entity of the formation specifically includes: Obtain the top surface mesh of the current stratum, and project and translate all vertices of the top surface mesh along the direction of gravity by a preset stretching threshold to construct a downwardly stretched body; Obtain the base surface mesh of the current stratum, and project and translate all vertices of the base surface mesh along the anti-gravity direction by the stretching threshold to construct an upwardly stretched body; Perform a Boolean intersection operation on the downwardly stretched body and the upwardly stretched body to construct the solid geometry, retain the common space region located below the top plate surface mesh and simultaneously above the bottom plate surface mesh, and generate a closed stratum three-dimensional solid that satisfies the manifold property.

5. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 1, characterized in that, In step S300, the geometric segmentation specifically includes: Construct a three-dimensional closed geometry as the spatial sectioning region; Calculate the Boolean intersection of the initial closed 3D stratum entity and the spatially cut region to obtain the stratum block to be processed; The Boolean difference set between the initial closed three-dimensional stratum entity and the spatially cut area is calculated to obtain the main stratigraphic block that retains the original sedimentary morphology; Using the analyzed fault geological parameters, a point-normal plane equation is constructed to further divide the strata block to be treated into the hanging wall region and the footwall region.

6. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 5, characterized in that, In step S300, the classification of the upper and lower plates specifically includes: Calculate the unit normal vector of the fault plane based on the strike angle and dip angle in the fault geological parameters; Calculate the directed Euclidean distance from any grid vertex in the stratigraphic block to the fault plane; Based on the sign of the directed Euclidean distance, the grid vertices are divided into an upper disk vertex set and a lower disk vertex set.

7. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 6, characterized in that, In step S300, applying a smooth displacement transformation based on spatial location weights specifically includes: Calculate the basis vector of sliding along the maximum dip direction of the fault plane, and calculate the theoretical maximum rigid displacement vector of the hanging wall and footwall by combining the fault displacement in the geological parameters of the fault. A normalized position parameter and a sinusoidal attenuation weight function are introduced. The sinusoidal attenuation weight function takes the maximum value at the fault plane position and attenuates to zero at the boundary of the spatial cutting region. By applying the sinusoidal attenuation weighting function to the vertex coordinates of the upper and lower plate point sets using nonlinear displacement transformation, the geometric deformation caused by the fault is maximized near the fault plane and gradually and smoothly attenuates towards the two side boundaries.

8. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 7, characterized in that, In step S300, the generation of fault structure blocks and geometric assembly specifically includes: The point set after the smooth displacement transformation is obtained, and the top and bottom surfaces of the hanging wall and footwall are reconstructed using the Kriging interpolation algorithm and the constrained Delaunay triangulation algorithm with fault traces as constraint edges. The progressive cutting method is adopted. First, the initial tensile body is cut using the fault plane to generate an intermediate body. Then, the intermediate body is trimmed using the reconstructed top and bottom plate surfaces to generate an independent fault structure block. Perform a Boolean union operation on the main stratigraphic block and the generated fault structure block to merge them into a stratigraphic model containing fault structures.

9. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 1, characterized in that, In step S400, the conversion to the planar boundary representation in the IFC standard specifically includes: Extract the triangular mesh data of the three-dimensional solid of the closed strata and the fault structure blocks; Instantiate the mesh vertices as IfcCartesianPoint Cartesian point objects, construct IfcPolyLoop polygon loop objects using triangular facet vertex references, and then construct IfcFace face objects. Aggregate all IfcFace objects into an IfcClosedShell closed shell container and encapsulate them into an IfcFacetedBrep entity type; Create an IfcBuildingElementProxy entity or an IfcGeotechnicalElement entity as a semantic container to carry the IfcFacetedBrep entity type, and establish a spatial hierarchy mapping relationship from the IfcProject project node to the IfcSite site node and then to the semantic container.

10. The method for automated coalfield geological modeling and fault integration based on IFC according to claim 9, characterized in that, In step S400, defining the geological-specific extended attribute set includes: Construct a basic stratigraphic information attribute set, which includes stratigraphic sequence number, lithological name, geological age, and display color attribute items; Construct a physical property information attribute set, which includes attribute items such as bulk density, permeability, and porosity; Construct a fault structural parameter attribute set, which includes fault unique number, fault nature, fault displacement and fault dip angle attributes; By creating an IfcRelDefinesByProperties relational entity, the geological-specific extended attribute set, after being populated with specific values, is bidirectionally bound to the corresponding geological entity object.

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