Method and System for Inferring Internal Spatial Relationship Based on Surface of Rock Mass Structural Plane

Abstract

The present invention discloses a method and system for inferring the internal spatial relationship based on the surface of rock mass structural planes. The method includes: constructing the association between the surface characteristics of rock mass structural planes and their internal spatial relationship based on the identification results of rock mass structural planes of bedding planes, joint planes and fault planes, and determining the surface constraint conditions of bedding planes, joint planes and fault planes; realizing the constant-thickness extension of rock mass structural planes based on the setting of key control points, thickness constraint and geometric calculation of irregular triangular networks; realizing the thickness-varying extension between different depth levels by deforming the triangulated surface mesh based on the thickness constraint; and realizing the stratigraphic pinch-out by trimming the irregular triangular network with the intersection line of intersecting rock mass structural planes. The present invention obtains the attitude information such as dip and dip angle of the internal structure of the rock mass and the internal spatial relationship of the rock mass structural planes by extending the surface of the structural planes, and then uses the inferred result of the internal spatial relationship of the rock mass as an internal constraint to provide data support for subsequent three-dimensional modeling.

Description

Technical Field

[0001] The present invention belongs to the field of geology, and particularly relates to a method and system for inferring the internal spatial relationship of sedimentary rocks. Background Art

[0002] Inferring the internal spatial relationship of rock mass structural planes is an important research field that provides basic data for geological engineering, civil engineering, and mining engineering, etc., to ensure the feasibility and safety of engineering construction. Rock mass structural planes such as faults and large joints are crucial for the stability of rock masses, and thus become key factors in engineering design and construction. The inference of the internal spatial relationship of rock mass structural planes mainly adopts the following two methods: one is to use spatial interpolation algorithms to interpolate between known data points; the other is to allow the combination of expert geological knowledge to establish connections between data points. Spatial interpolation algorithms deduce the spatial attribute values of unknown points by interpolating between known data points and present spatial characteristics with a continuous data surface. The theoretical assumption for its implementation is that the closer the spatial positions are, the more similar the characteristic values are, and vice versa, the lower the similarity. However, domestic and foreign research mainly relies on borehole data to infer the internal spatial relationship of rock mass structural planes. The sparsity of borehole data results in insufficient accuracy and integrity of the constructed relationship, making it difficult to apply to the inference of the internal spatial relationship of complex geological bodies. And the method of combining expert geological knowledge has strong subjectivity and poor replicability, which limits its application scenarios.

[0003] Generally speaking, many geostatistical and database technologies can be used to interpolate between geological surveys, especially at the regional scale. However, these methods are usually not applicable to unevenly distributed data and may not be able to properly handle the qualitative and interpretive factors of geology. Summary of the Invention

[0004] Object of the Invention: Aiming at the deficiencies of the prior art, the present invention proposes a method and system for inferring the internal spatial relationship based on the surface of rock mass structural planes. By extending the surface of the structural plane, attitude information such as the dip and dip direction of the internal structure of the rock mass and the internal spatial relationship of the rock mass structural plane are obtained. Furthermore, the inference result of the internal spatial relationship of the rock mass is used as an internal constraint to provide data support for subsequent 3D modeling.

[0005] Technical Solution: According to the first aspect of the present invention, a method for inferring the internal spatial relationship based on the surface of rock mass structural planes includes the following steps:

[0006] S1: Extract the rock mass structural characteristics and spatial relationships of the stratigraphic surface, joint surface, and fault surface from the three-dimensional surface model data of the rock mass structure, construct the association between the surface characteristics of the rock mass structural plane and its internal spatial relationship, determine the surface constraint conditions of the stratigraphic surface, joint surface, and fault surface, and update the results to the fact library;

[0007] S2: Under the constraint conditions determined in step S1, based on the key control point setting, thickness constraint, and geometric calculation of the irregular triangular network, realize the invariant extension of the thickness of the rock mass structural plane, specifically including: starting from the known control points, based on the attitude and interpolation algorithm of the rock mass structural surface, determine the positions of the control points in the unknown area; according to the determined positions of the control points, based on the Graham-Scan convex hull algorithm, determine the boundary constraints of the rock mass structural surface, and under the boundary constraints, extend each stratum upward or downward from the reference plane, keeping the vertical distance from the reference plane unchanged;

[0008] S3: Obtain the thickness data between different depth levels of the rock mass structure, obtain the layer thicknesses of each triangle in the irregular triangular network at different depths through interpolation processing, and realize the deformation of the triangulated surface mesh under the specified thickness constraint, so as to realize the thickness change extension between different depth levels;

[0009] S4: Obtain the surface data of the rock mass structural plane, calculate the intersection lines of the intersecting rock mass structural planes, and clip the irregular triangular network based on the intersection lines to realize the stratigraphic pinch-out.

[0010] According to some embodiments of the first aspect, in step S1, the constraint conditions include point constraint conditions, line constraint conditions, and surface constraint conditions, and the determination methods are as follows:

[0011] Extract the boundary point set of the rock mass structural plane based on the Graham-Scan convex hull algorithm and the Douglas-Peuker point cloud feature thinning algorithm. According to the boundary point set, under the specified key point extraction rules, obtain the spatial information of all key points as the point constraint conditions for internal relationship speculation;

[0012] Extract the trace lines of the rock mass structure based on digital image technology. According to the trace lines of the rock mass structure, under the specified constraint line extraction rules, obtain the spatial information of all constraint lines as the line constraint conditions for internal relationship speculation;

[0013] Preliminarily extract the dip angle and dip direction information of the rock mass structural plane based on the region growing method, and then update the fact base to store the dip direction, dip angle, and adjacent structural plane information of the rock mass structural plane as the surface constraint conditions for internal relationship speculation.

[0014] According to some embodiments of the first aspect, in step S2, starting from the known control points, based on the attitude and interpolation algorithm of the rock mass structural surface, determining the positions of the control points in the unknown area includes:

[0015] Determine the stratum interfaces that need to be extended, and identify the key control points on each interface according to the obtained spatial information of the key points;

[0016] Determine the neighboring sampling points of the point to be interpolated. Based on the coordinate values and elevation values of these neighboring sampling points, use the inverse distance weighted IDW algorithm to calculate the elevation value of the interpolated point.

[0017] According to some embodiments of the first aspect, the IDW algorithm calculates the elevation value of the interpolated point, including:

[0018] For the point to be interpolated P(x, y, z) and a set of neighboring data points (X, Y, Z), where i = 1, 2, 3…n, calculate the elevation value of the interpolated point through the formula:

[0019]

[0020] w i (x) = 1 / d(x, x i ) m

[0021]

[0022] where x i is the neighboring abscissa point, z i is the nearby elevation value, N is the number of sample points used for interpolation, m is a positive integer power, and w i is the reciprocal of the sum of the squares of the Euclidean distances between the interpolated point and the known neighboring points.

[0023] According to some embodiments of the first aspect, in the step S2, based on the Graham-Scan convex hull algorithm, determine the boundary constraints on the surface of the rock mass structural plane, and under the boundary constraints, extend each stratum upward or downward from the reference plane while keeping the vertical distance from the reference plane unchanged, including:

[0024] Based on the Graham-Scan convex hull algorithm, determine the boundary constraints on the surface of the rock mass structural plane, and deduce the internal boundary line of the rock mass structural plane under the constructed surface constraint conditions;

[0025] Connect the upper and lower boundaries to construct the overall boundary constraints, and delete the interpolated points outside the boundary based on the boundary constraints;

[0026] Starting from the reference plane, extend each stratum upward or downward while keeping the vertical distance from the reference plane unchanged.

[0027] According to some embodiments of the first aspect, in the step S3, through interpolation processing, obtain the layer thicknesses of each triangle of the irregular triangular network at different depths, and realize the deformation of the triangularized surface mesh under the specified thickness constraint, including:

[0028] For each triangle, according to the depth information of its vertices and the corresponding layer thickness data between layers, perform interpolation processing to calculate the layer thicknesses of each triangle at different depths;

[0029] Generate new vertex coordinates based on the layer thickness data obtained by interpolation, representing the formation horizons at different depths.

[0030] Taking into account the position constraints of the vertices of the surface mesh, construct a new irregular triangular network according to the obtained new vertex coordinates, and calculate the new positions of the vertices of the surface mesh.

[0031] According to some embodiments of the first aspect, in step S4, obtain the data of the rock mass structural plane, including the spatial position and geometric shape of the formation horizon, and calculate the intersection line of the intersecting rock mass structural planes based on the spatial position and geometric shape of the formation horizon.

[0032] Clip the irregular triangular network based on this intersection line to achieve formation pinch-out, including: inserting the formation pinch-out line as a constraint condition into the irregular triangular network, and performing the clipping operation of the irregular triangular network model according to the constraint line, so as to achieve the effect of formation pinch-out.

[0033] According to the second aspect of the present invention, a system for inferring the internal spatial relationship based on the surface of the rock mass structural plane includes:

[0034] A constraint condition determination module, configured to extract the rock mass structural characteristics and spatial relationships of the formation horizon, joint plane, and fault plane from the three-dimensional surface model data of the rock mass structure, construct the association between the surface characteristics of the rock mass structural plane and its internal spatial relationships, determine the surface constraint conditions of the formation horizon, joint plane, and fault plane, and update the results to the fact base.

[0035] A thickness-invariant extension module, configured to achieve the thickness-invariant extension of the rock mass structural plane based on the setting of key control points, thickness constraints, and geometric calculations of the irregular triangular network under the determined constraint conditions. Specifically, it includes: a control point setting unit, configured to start from known control points and determine the positions of control points in unknown areas based on the attitude and interpolation algorithm of the rock mass structure surface; a vertical extension unit, configured to determine the boundary constraints of the surface of the rock mass structural plane based on the Graham-Scan convex hull algorithm according to the determined control point positions, and under the boundary constraints, extend each formation upward or downward from the reference plane, keeping the vertical distance from the reference plane unchanged.

[0036] A thickness-variable extension module, configured to obtain the thickness data between different depth horizons of the rock mass structure, obtain the layer thickness of each triangle of the irregular triangular network at different depths through interpolation processing, and realize the deformation of the triangulated surface mesh under the specified thickness constraint, so as to achieve the thickness-variable extension between different depth horizons.

[0037] A formation pinch-out processing module, configured to obtain the surface data of the rock mass structural plane, calculate the intersection line of the intersecting rock mass structural planes, and clip the irregular triangular network based on this intersection line to achieve formation pinch-out.

[0038] According to a third aspect of the present invention, there is provided a computer device, including: one or more processors; a memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, and when the program is executed by the processor, it implements the steps of the method for inferring the internal spatial relationship based on the surface of the rock mass structural plane as described in the first aspect of the present invention.

[0039] According to a fourth aspect of the present invention, there is provided a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the method for inferring the internal spatial relationship based on the surface of the rock mass structural plane as described in the first aspect of the present invention.

[0040] Beneficial effects: The present invention designs a method for inferring the internal spatial relationship based on the surface of the rock mass structural plane based on high-precision point cloud data in the field area, extracts the characteristic information of the surface point cloud data and image data as constraint conditions, constructs the association between the surface characteristics of the rock mass structural plane and its internal spatial relationship on this basis, and designs the rock mass structural plane extension algorithms in three scenarios of constant thickness, variable thickness, and formation pinch-out between rock mass structural planes based on the key control point setting, thickness constraint, and geometric calculation of the irregular triangular network. The present invention realizes obtaining the attitude information such as the dip and dip angle of the internal structure of the rock mass and the internal spatial relationship of the rock mass structural plane by extending the surface of the structural plane, and further uses the inferred result of the internal spatial relationship of the rock mass as an internal constraint to provide data support for subsequent three-dimensional modeling. Compared with the prior art of inferring the internal spatial relationship of the rock mass based on borehole data, the method of the present invention is more convenient, has lower costs, and avoids the problems of inaccurate and incomplete inferred relationships caused by sparse boreholes, and can be applied to the inference of the internal spatial relationship of complex geological bodies, with strong practicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is the three-dimensional model data (left) and triangular network data (right) corresponding to the research area in the embodiment of the present invention;

[0042] Figure 2 is the flowchart of the method for inferring the internal spatial relationship based on the surface of the rock mass structural plane of the present invention;

[0043] Figure 3 is the layer diagram corresponding to the present invention;

[0044] Figure 4 is the joint plane diagram corresponding to the present invention;

[0045] Figure 5 is the fault geometric element diagram corresponding to the present invention;

[0046] Figure 6 is the flowchart of the implementation of the region growing method corresponding to the present invention;

[0047] Figure 7 It is a schematic diagram of interpolation of constraint data points corresponding to the present invention;

[0048] Figure 8 It is a schematic diagram of boundary constraints corresponding to the present invention;

[0049] Figure 9 An example analysis diagram of the internal spatial relationship speculation algorithm based on the surface of the rock mass structural plane;

[0050] Figure 10 It is the initial surface mesh (left) and the application effect diagram of the deformation algorithm (right) corresponding to the present invention;

[0051] Figure 11 It is a schematic diagram of the clipping algorithm for the irregular triangular network corresponding to the present invention;

[0052] Figure 12 It is the speculation result of the internal spatial relationship corresponding to the present invention. Specific embodiments

[0053] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0054] In the embodiment of the present invention, the small-scale rock mass structural characteristics of the Nanjing Tangshan Mine Park are taken as the research object, and the surface data of the rock mass structural plane in the research area is obtained for speculation of the internal spatial relationship. The multi-rotor UAV DJI M300 RTK is used as the flight platform and DJI Zenmuse P1 is used as the load to collect data in the research area. The oblique three-dimensional reconstruction technology is used to construct a three-dimensional surface model for in-house data processing, so as to obtain the scene point cloud and its three-dimensional surface model data of the research area, as Figure 1 shown, (a) is the three-dimensional model data corresponding to the research area, and (b) is the triangular network data, which is used as the input of the method of the present invention.

[0055] Referring to Figure 2 , the method for speculating the internal spatial relationship based on the surface of the rock mass structural plane proposed by the present invention includes the following steps:

[0056] Step (1), based on the region growing method and the "Rock Mass Structural Feature Recognition Method Considering Spatial Relationships in Complex Scenarios" (Patent No.: ZL202310739126.X), extract the rock mass structural features and spatial relationships of the stratigraphic surface, joint surface, and fault surface from the three-dimensional surface model data of the rock mass structure (see Figures 3 - 5 respectively), construct the association between the surface features of the rock mass structural plane and its internal spatial relationship, determine the surface constraint conditions of the stratigraphic surface, joint surface, and fault surface, and update the results to the fact library, specifically including:

[0057] (1-1) Point constraint conditions for determining the internal extension of structural planes based on the geometric elements of rock mass structures: Based on the Graham-Scan convex hull algorithm and the Douglas-Peuker point cloud feature thinning algorithm, the boundary point set of the rock mass structural plane is extracted. Then, combined with the spatial relationships between the rock mass structural planes extracted in this patent, the extraction rules for key points are set, that is, rules are defined by combining the geographical knowledge base and the fact base constructed in this patent (the intersection points of rock strata with topological relationships or contact relationships, the starting points of stratigraphic sequences, etc. in the fact base are defined as key points). Through the rule engine of this patent, rule matching, agenda triggering, and Drools execution are carried out to obtain the spatial information of all key points, which serves as the point constraint conditions for subsequent speculation of internal relationships;

[0058] (1-2) Line constraint conditions for determining the internal extension of structural planes based on the geometric elements of rock mass structures: Based on digital image technology (image segmentation - denoising - dilation and erosion - filtering - thinning and deburring), the trace lines of the rock mass are extracted. Then, combined with the spatial relationships between the rock mass structural planes extracted in this patent, the extraction rules for key line segments are set, that is, rules are defined by combining the geographical knowledge base and the fact base constructed in this patent (the boundaries of rock strata with topological relationships or contact relationships, the contact lines between stratigraphic sequences, etc. in the fact base are defined as constraint lines). Through the rule engine of this patent, rule matching, agenda triggering, and Drools execution are carried out to obtain the spatial information of all constraint lines, which serves as the line constraint conditions for subsequent speculation of internal relationships;

[0059] (1-3) Plane constraint conditions for determining the internal extension of structural planes based on the region growing method and the geometric elements of rock mass structures: Based on the region growing method, the dip angle and dip direction information of the rock mass structural plane are initially extracted. Then, the fact base is updated to store the dip direction, dip angle, and adjacent structural plane information of the rock mass structural plane, which serves as the plane constraint conditions for subsequent speculation of internal relationships.

[0060] The implementation process of the region growing method is as Figure 6 shown, referring to Figure 6 , the specific steps of step (1-3) include:

[0061] (1-3-1) According to the basic situation of the research area, set the seed triangle Pi;

[0062] (1-3-2) According to the triangular mesh topological relationship, set the growth rule, grow outward based on the seed triangle, and expand the candidate point set of the current plane by adding adjacent similar triangular meshes Qj;

[0063] (1-3-3) Calculate the normal vector angle α between adjacent triangular patches (Pi, Qj), calculate the angle θ between Qj and the average normal vector of the plane Ai where Pi is located, and perform the α, θ threshold judgment. When there are no edge points to be queried or the remaining points can no longer satisfy the candidate points of the target rule, this growth is completed, and the plane set An is generated.

[0064] (1-3-4) Update the attitude information such as dip and dip angle of each plane in the fact database. Subsequently, the rock mass structural planes will extend inward based on this attitude information.

[0065] Step (2), based on the key control point setting, thickness constraint, and geometric calculation of the Triangulated Irregular Network (TIN), achieve the invariant extension of the rock mass structural plane thickness, specifically including:

[0066] (2-1) Starting from the known control points, based on the attitude of the rock mass structural surface and the interpolation algorithm, determine the positions of the control points in the unknown area;

[0067] (2-2) Based on the Graham-Scan convex hull algorithm, determine the boundary constraints of the rock mass structural plane surface. Starting from the reference plane, extend each stratum upward or downward, keeping the perpendicular distance from the reference plane (i.e., the stratum thickness) unchanged.

[0068] Furthermore, step (2-1) includes:

[0069] (2-1-1) Determine the stratum interface to be extended, and mark the key control points on each interface based on the key point spatial information obtained in step (1-1);

[0070] (2-1-2) Determine the adjacent sampling points of the interpolation points. According to the coordinate values and elevation values of these adjacent points, use the inverse distance weighted IDW algorithm to calculate the elevation value of the interpolation points. Specifically, for the interpolation point P(x, y, z) and a group of its adjacent data points (X, Y, Z), i = 1, 2, 3…n, calculate the elevation value of the interpolation point through the formula:

[0071]

[0072] w i (x) = 1 / d(x, x i ) m

[0073]

[0074] where x i is the adjacent abscissa point, z i is the nearby elevation value, N is the number of sample points used for interpolation, m is the positive integer power (generally, values from 0.5 to 3 can obtain the most reasonable results), and w i is the reciprocal of the sum of the squares of the Euclidean distances between the interpolation point and the known adjacent points, that is, the weight. For example Figure 7As shown in the figure, (a) is a schematic diagram of the original structural plane before interpolation, and (b) is a schematic diagram after interpolation. The red points are the control points established according to the idea of the present invention, that is, the constrained data points, and the blue ones are the interpolated data points.

[0075] Furthermore, step (2-2) includes:

[0076] (2-2-1) Determine the boundary constraints on the surface of the rock mass structural plane based on the Graham-Scan convex hull algorithm, and calculate the internal boundary line of the rock mass structural plane under the surface constraint conditions constructed in step (1);

[0077] (2-2-2) Connect the upper and lower boundaries to construct the overall boundary constraints, and delete the interpolated points outside the boundary based on the boundary constraints. The schematic diagram of the boundary constraints is as Figure 8 shown, where (a) is the schematic diagram of the original structural plane, and (b) is the schematic diagram of the constructed boundary constraints;

[0078] (2-2-3) Starting from the reference plane, extend each stratum upward or downward, keeping the vertical distance from the reference plane (i.e., the stratum thickness) unchanged. The result diagram of the algorithm applied in the example is as Figure 9 shown in (a) of the figure. Starting from the reference planes of the blue, purple, and green layers respectively, extend downward and keep the vertical distance (i.e., the stratum thickness) between each layer unchanged.

[0079] Step (3), realizing the deformation of the triangulated surface mesh based on the thickness constraint, and further realizing the thickness change extension between different depth layers, specifically including:

[0080] (3-1) Obtain the thickness data between different depth layers of the rock mass structure through profile data, virtual data or other data;

[0081] (3-2) Conduct linear interpolation processing. For each triangle in the TIN, according to the depth information of its vertices and the corresponding thickness data between layers, use the IDW algorithm for interpolation processing to calculate the layer thickness of each triangle at different depths;

[0082] (3-3) Generate new vertex coordinates according to the interpolated layer thickness data, representing the stratum layers at different depths;

[0083] (3-4) Realize the deformation of the triangulated surface mesh based on the thickness constraint, that is, under the condition of considering the position constraints of some vertices of the surface mesh, construct a new irregular triangular network according to the obtained new vertex coordinates to calculate the new positions of the vertices of the surface mesh. The application effect of its deformation algorithm is as Figure 10 shown in the figure. The region of interest has the characteristics of green vertices (unconstrained vertices) and red vertices (control vertices), Figure 10(a) in it is the initial surface mesh, and (b) is the effect diagram of the application of the deformation algorithm. Through the deformation of the triangularized surface mesh, the thickness change and extension are realized.

[0084] The result diagram of the algorithm application in the example is as Figure 9 shown in (b) of it. It is known that the purple, red, and green layers are parallel layers, and the red layer and the green layer intersect. The thickness change and extension algorithm changes its original thickness (0.56m) and sets its final thickness to half (1.17m) of the thickness (2.34m) between the purple and green layers to achieve the thickness change and extension between the layers.

[0085] Step (4), based on the intersection line of the intersecting rock mass structural planes, clip the irregular triangular network to achieve the stratigraphic pinch-out, specifically including:

[0086] (4-1) Obtain the data of the rock layer structural planes, including the spatial position and geometric shape of the stratum surface, and calculate the intersection line of the intersecting rock mass structural planes as the constraint condition;

[0087] (4-2) Insert the stratigraphic pinch-out line as a constraint condition into the irregular triangular network, and perform the clipping operation of the TIN model according to the constraint line, that is, remove the part between the stratigraphic pinch-out points and retain the effective stratigraphic structure; The flow chart of the clipping algorithm is as Figure 11 shown, so as to achieve the effect of stratigraphic pinch-out.

[0088] The result diagram of the algorithm application in the example is as Figure 9 shown in (c) of it. Through the known or set pinch-out conditions, the blue layer undergoes pinch-out during the extension process. When the distance between two layers meets the pinch-out conditions, the intersection line of the two layers is defined as the pinch-out line (as shown by the black line in (c) of Figure 9 it), and according to the superposition principle, the layer with a newer formation time after the pinch-out line is removed.

[0089] Step (5), sequentially execute steps (2), (3), and (4) to obtain the final inferred result of the internal spatial relationship (as shown in Figure 12 it). It can be seen that the example has 12 joint planes and 31 layers. Based on the inferred result diagram of the internal spatial relationship, the internal spatial distribution of the rock mass structural planes in the example can be clearly seen.

[0090] Based on the same technical concept as the method embodiment, the present invention also provides an internal spatial relationship inference system based on the surface of the rock mass structural plane, including:

[0091] The constraint condition determination module is used to extract the rock mass structure characteristics and spatial relationships of the stratigraphic plane, joint plane, and fault plane from the three-dimensional surface model data of the rock mass structure, construct the association between the surface characteristics of the rock mass structural plane and its internal spatial relationships, determine the surface constraint conditions of the stratigraphic plane, joint plane, and fault plane, and update the results to the fact base;

[0092] The constant-thickness extension module is used to realize the constant-thickness extension of the rock mass structural plane under the determined constraint conditions based on the key control point setting, thickness constraint, and geometric calculation of the irregular triangular network. Specifically, it includes: a control point setting unit, which is used to start from the known control points and determine the positions of the control points in the unknown area based on the attitude and interpolation algorithm of the rock mass structure surface; a vertical extension unit, which is used to determine the boundary constraints of the rock mass structural plane surface based on the Graham-Scan convex hull algorithm according to the determined control point positions, and under the boundary constraints, extend each stratum upward or downward from the reference plane while keeping the vertical distance from the reference plane unchanged;

[0093] The variable-thickness extension module is used to obtain the thickness data between different depth levels of the rock mass structure, obtain the layer thickness of each triangle of the irregular triangular network at different depths through interpolation processing, and realize the variable-thickness extension between different depth levels by deforming the triangulated surface mesh under the specified thickness constraint;

[0094] The stratum pinch-out processing module is used to obtain the surface data of the rock mass structural plane, calculate the intersection line of the intersecting rock mass structural planes, and clip the irregular triangular network based on the intersection line to realize the stratum pinch-out.

[0095] It should be understood that the internal spatial relationship speculation system based on the surface of the rock mass structural plane in the embodiments of the present invention can implement all the technical solutions in the above method embodiments. The functions of its respective functional modules can be specifically implemented according to the methods in the above method embodiments, and the specific implementation process can refer to the relevant descriptions in the above embodiments, which will not be elaborated here.

[0096] The present invention also provides a computer device, including: one or more processors; a memory; and one or more programs, where the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and when the program is executed by the processor, it implements the steps of the above-mentioned method for speculating the internal spatial relationship based on the surface of the rock mass structural plane.

[0097] The present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the above-mentioned method for speculating the internal spatial relationship based on the surface of the rock mass structural plane.

[0098] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, an apparatus (system), a computer device, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) containing computer-usable program code.

[0099] The present invention is described with reference to the flowchart of the method according to the embodiments of the present invention. It should be understood that each process in the flowchart and the combination of processes in the flowchart can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one process or multiple processes.

[0100] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing devices to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device that implements the functions specified in Figure 1 one process or multiple processes.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing devices, such that a series of operation steps are executed on the computer or other programmable devices to generate a computer-implemented process, so that the instructions executed on the computer or other programmable devices provide steps for implementing the functions specified in Figure 1 one process or multiple processes.

Claims

1. A method for estimating internal spatial relations based on the surface of a rock mass structural surface, characterized in that: The steps include: S1: Extract the rock mass structure characteristics and spatial relationships of the stratigraphic plane, joint plane, and fault plane from the three-dimensional surface model data of the rock mass structure, construct the association between the surface characteristics of the rock mass structure plane and its internal spatial relationship, determine the surface constraints of the stratigraphic plane, joint plane, and fault plane, and update the results to the fact base; S2: Under the constraints determined in step S1, based on the key control point setting, thickness constraint and geometric calculation of the irregular triangulated network, the thickness of the rock structure surface is extended unchanged, specifically including: starting from the known control points, based on the occurrence and interpolation algorithm of the rock structure surface, the control point position of the unknown area is determined; according to the determined control point position, the boundary constraint of the rock structure surface is determined based on the Graham-Scan convex hull algorithm, and under the boundary constraint, each stratum is extended upward or downward from the reference plane, keeping the vertical distance from the reference plane unchanged; S3: Obtain the thickness data between layers at different depths of the rock mass structure, obtain the layer thickness of each triangle of the irregular triangulated network at different depths through interpolation processing, realize the deformation of the triangulated surface mesh under the specified thickness constraint, and then realize the thickness change extension between layers at different depths; S4: Obtain the surface data of the rock mass structural surface, calculate the intersection line of the intersecting rock mass structural surfaces, and cut the irregular triangulated network based on the intersection line to achieve stratum pinch-out.

2. The method according to claim 1, characterized in that In step S1, the constraint conditions include point constraint conditions, line constraint conditions, and surface constraint conditions, and the determination method is as follows: Based on the Graham-Scan convex hull algorithm and the Douglas-Peuker point cloud feature thinning algorithm, the boundary point set of the rock mass structural surface is extracted. According to the boundary point set and under the specified key point extraction rules, the spatial information of all key points is obtained as the point constraint condition for internal relationship inference. Extract rock mass structure traces based on digital image technology, and obtain all constraint line spatial information according to the rock mass structure traces under the specified constraint line extraction rules as the line constraint conditions for internal relationship inference; Based on the regional growing method, the inclination and dip information of the rock mass structural surface is preliminarily extracted, and then the fact database is updated to store the inclination, dip and adjacent structural surface information of the rock mass structural surface as the surface constraint conditions for internal relationship inference.

3. The method according to claim 2, characterized in that In step S2, starting from the known control points, based on the occurrence of the rock mass structure surface and the interpolation algorithm, the control point positions of the unknown area are determined, including: Determine the stratigraphic interfaces that need to be extended, and identify key control points on each interface based on the key point spatial information obtained; Determine the neighboring sampling points of the point to be interpolated, and calculate the elevation value of the interpolation point using the inverse distance weighted IDW algorithm based on the coordinate values ​​and elevation values ​​of these neighboring sampling points.

4. The method according to claim 3, characterized in that The IDW algorithm calculates the elevation value of the interpolation point, including: For the interpolation point P (x, y, z) and its adjacent set of data points (X, Y, Z), i = 1, 2, 3 ... n, the elevation value of the interpolation point is calculated by the formula: w i (x)=1 / d(x,x i ) m Among them, x i is the adjacent horizontal coordinate point, z i is the nearby elevation value, N is the number of sample points used for interpolation, m is a positive integer power, and w i It is the reciprocal of the sum of squared Euclidean distances between the interpolated point and its known neighboring points.

5. The method according to claim 2, characterized in that: In step S2, the boundary constraints of the surface of the rock mass structural plane are determined based on the Graham-Scan convex hull algorithm, and under the boundary constraints, each stratum is extended upward or downward from the reference plane to keep the vertical distance from the reference plane unchanged, including: The boundary constraints of the rock mass structural surface are determined based on the Graham-Scan convex hull algorithm, and the internal boundaries of the rock mass structural surface are deduced under the constructed surface constraints. Connect the upper and lower boundaries to construct the overall boundary constraint, and delete the interpolation points outside the boundary based on the boundary constraint; Starting from the datum, extend each stratum upward or downward, maintaining a constant vertical distance from the datum.

6. The method according to claim 1, characterized in that In step S3, the layer thickness of each triangle of the irregular triangulated network at different depths is obtained by interpolation processing, and the triangulated surface mesh deformation is realized under the specified thickness constraint, including: For each triangle, interpolation processing is performed based on the depth information of its vertices and the corresponding inter-layer thickness data to calculate the layer thickness of each triangle at different depths; According to the interpolated layer thickness data, new vertex coordinates are generated to represent the stratigraphic layers at different depths; Taking into account the position restrictions of the surface mesh vertices, a new irregular triangulated network is constructed according to the obtained new vertex coordinates, and the new positions of the surface mesh vertices are calculated.

7. The method according to claim 1, characterized in that In the step S4, data of the rock formation structural surface is obtained, including the spatial position and geometric shape of the stratigraphic surface, and the intersection line of the intersecting rock formation structural surface is calculated based on the spatial position and geometric shape of the stratigraphic surface; The irregular triangulated network is trimmed based on the intersection line to achieve stratum pinch-out, including: inserting the stratum pinch-out line into the irregular triangulated network as a constraint condition, and performing a trimming operation on the irregular triangulated network model according to the constraint line, thereby achieving the stratum pinch-out effect.

8. A system for estimating internal spatial relations based on the surface of a rock mass structure, characterized in that: include: The constraint condition determination module is used to extract the rock structure characteristics and spatial relationships of the stratigraphic plane, joint plane, and fault plane from the three-dimensional surface model data of the rock structure, to build the association between the surface characteristics of the rock structure plane and its internal spatial relationship, to determine the surface constraint conditions of the stratigraphic plane, joint plane, and fault plane, and to update the results to the fact base; The thickness-invariant extension module is used to achieve thickness-invariant extension of the rock mass structure surface based on key control point setting, thickness constraints and geometric calculations of irregular triangulated networks under certain constraints. Specifically, it includes: a control point setting unit, which is used to determine the control point positions of unknown areas based on the occurrence and interpolation algorithms of the rock mass structure surface from known control points; a vertical extension unit, which is used to determine the boundary constraints of the rock mass structure surface based on the Graham-Scan convex hull algorithm according to the determined control point positions, and to extend each stratum upward or downward from the reference plane under the boundary constraints, keeping the vertical distance from the reference plane unchanged; Thickness variation extension module is used to obtain thickness data between layers at different depths of rock mass structure, obtain the thickness of each triangle of irregular triangulated network at different depths through interpolation processing, realize triangulated surface mesh deformation under specified thickness constraints, and then realize thickness variation extension between layers at different depths; The formation pinch-out processing module is used to obtain the surface data of the rock structure surface, calculate the intersection line of the intersecting rock structure surfaces, and cut the irregular triangulated network based on the intersection line to achieve formation pinch-out.

9. A computer device, characterized in that: include: one or more processors; Memory; And one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and when the programs are executed by the processors, the steps of the method for inferring the internal spatial relationship based on the surface of the rock structure surface as described in any one of claims 1-7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for inferring the internal spatial relationship based on the surface of a rock mass structural surface as described in any one of claims 1 to 7 are implemented.

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