Arch dam simulation analysis method and system based on topographic and geological reconstruction

Abstract

The application provides an arch dam simulation analysis method and system based on terrain and geological reconstruction, which comprises the following steps: based on dam body parameterization control information, generating dam body flood discharge orifice, full-elevation radial twist surface transverse joint and foundation surface transition thin layer, and constructing an arch dam body structure model; based on terrain and geological data, reconstructing dam shoulder slope, and establishing a closed excavation simulation terrain model; based on weathering layer and structure surface information, constructing a geological partition model through topological cutting, boundary closing and redundant body elimination; integrating the arch dam body structure model and the geological partition model; classifying, extracting and segmenting dam body structure control lines, excavation boundary control lines and structure surface control lines, and generating an overall three-dimensional finite element grid; according to the partition result, corresponding material parameters are given, boundary conditions and external loads are applied for numerical solution, so that fine simulation analysis and result output of an arch dam-foundation system under real terrain and geological conditions are realized.

Description

Technical Field

[0001] This invention belongs to the field of finite element simulation analysis technology for hydraulic structures, and particularly relates to a simulation analysis method and system for arch dams based on topographic and geological reconstruction. Background Technology

[0002] Arch dams, as typical high-head, long-span spatial shell water-retaining structures, are subject to various factors, including the dam's shape, abutment topography, foundation excavation morphology, weathered layers, lithology, and structural surfaces, in addition to their structural stress state. In high arch dam projects, employing refined simulation analysis methods that more closely approximate real engineering conditions is crucial for accurately evaluating the stress, deformation, and overall performance of the dam-foundation system.

[0003] Existing simulation analysis methods for arch dams are mostly based on idealized dam bodies and simplified ground topography to establish finite element models. To reduce modeling complexity, the dam body is usually simplified to a smooth structure without orifices and transverse joints, or only local details are treated separately. Meanwhile, geological conditions such as dam abutment slopes, excavated terrain, weathered layers, and geological structural surfaces are often simplified using regularized or homogenized methods because there is still a significant conversion barrier between the three-dimensional geometric model and the finite element calculation model. While this type of method can meet general analysis needs, it has the following shortcomings under complex terrain and geological conditions: 1. Insufficient representation of dam body details. Existing methods often fail to accurately represent structural features such as dam body openings and transverse joints. Even when transverse joint model simulation is considered, the model is often built using planar cutting methods, which makes it difficult to reflect the true distribution of transverse joints along the spatial curved surface of the dam body. This leads to deviations between the joint arrangement of dam sections and the actual engineering, and further affects the accuracy of local stress distribution and overall stress analysis results.

[0004] 2. Insufficient representation of topographic and geological conditions. For complex geological information such as dam abutment slopes, excavation simulation topography, weathered layers, and structural surfaces, existing models often use artificial simplification methods, resulting in distorted representation of topographic boundaries, difficulty in accurately reflecting structural features such as ramps, slopes, and stilling basins in excavation models, and the use of homogeneous approximations in the foundation area, making it difficult to realistically represent the cutting and intersecting relationships between complex geological bodies such as structural surfaces and faults.

[0005] 3. Lack of integrated modeling and analysis methods for dam body, excavation, and geology. Existing technologies often limit refined modeling methods to geometric representations, making them difficult to apply directly to complex finite element simulations. Furthermore, methods geared towards finite element analysis typically simplify the detailed structure of the dam body, excavation topography, and geological conditions, making it difficult to balance model realism with analytical accuracy. Because dam body modeling, excavation topography construction, and geological zoning are separated, there is a lack of a unified, systematic technical approach that allows for direct application to refined simulation analysis. This easily leads to problems such as inconsistent model boundaries, discontinuous computational nodes, unclear zoning relationships, and distorted analysis results.

[0006] 4. Insufficient automation in modeling and analysis processes. In complex arch dam projects, processes such as topographic and geological reconstruction, solid cutting and closure, mesh segmentation control, and material assignment often rely on a large amount of manual operation. This is not only inefficient, but also the modeling quality is significantly affected by human experience, making it difficult to meet the consistency and repeatability requirements of fine simulation analysis for large and complex projects.

[0007] Therefore, existing technologies lack a systematic method that can uniformly consider the fine structure of the dam body, the simulated topography of the excavation, and the geological zoning characteristics, and achieve fine simulation analysis of the arch dam-foundation system under real topographic and geological conditions. To this end, it is necessary to propose a fine simulation analysis method for arch dams based on topographic and geological reconstruction to improve the realism, integration, and simulation accuracy of complex arch dam engineering analysis models. Summary of the Invention

[0008] To address the problems in existing technologies, such as inaccurate simulation of dam details, insufficient representation of complex terrain and geological conditions, and difficulty in unifying and directly applying dam, excavation, and geological models to finite element fine analysis, this invention proposes a fine simulation analysis method for arch dams based on terrain and geological reconstruction.

[0009] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A simulation analysis method for arch dams based on topographic and geological reconstruction includes the following steps: A smooth arch dam model was constructed. The positions of each spillway opening were determined with the same radial center. The smooth arch dam model was then cut to form openings in the dam body. A radial twisted transverse joint and a thin transition layer on the foundation surface were constructed to obtain the arch dam structure model. A foundation model is constructed based on topographic point cloud data, and an excavation cutting model is generated from the thin transition layer edge of the foundation surface according to the excavation control parameters; a closed excavation simulation terrain model is formed through Boolean operations between the excavation cutting model and the foundation model. Spatial positioning is achieved by extracting the attitude information of the structural plane; a structural plane influence zone entity with thickness is generated based on the width of the structural plane influence zone; the weathering layer is reconstructed based on the weathering layer information; the structural plane influence zone entity, the reconstructed weathering layer, and the closed excavation simulation terrain model are used as boundary constraints, and topological cutting and closure processing is performed on the foundation area based on the closed excavation simulation terrain model; the interface intersection relationship is identified and entity cutting, boundary closure, and redundant body removal are performed iteratively to obtain the geological zoning model; The arch dam structure model and the geological zoning model are spatially registered and integrated, and topologically processed to form an overall geometric model of the arch dam and foundation. Various control lines are classified, extracted, and segmented. Based on the segmentation results, dam body mesh, transition thin layer mesh, and foundation mesh are generated respectively, and the coordination between the fine dam body mesh and the coarse foundation mesh is achieved through the transition thin layer unit. According to the geological attribute information corresponding to each geological zoning, the corresponding material attribute parameters are assigned to form an overall three-dimensional finite element model of the arch dam and foundation that can be directly used for finite element solution. After applying boundary conditions and loads to the model, it can be solved.

[0010] Furthermore, the locations of each spillway opening are determined using the same radial center, and the smooth dam model of the arch dam is cut to form the dam body openings, including: Determine the coordinates of the radial center point of the dam's spillway gate and construct the gate's column cutting body; Boolean cutting was performed on the smooth arch dam model using the aforementioned orifice column cutting body to form an open structure in the dam body; Among them, the flood discharge outlets of each dam body at the same central elevation adopt the same radial center and are arranged radially along the radial center.

[0011] Furthermore, the radial torsion surface transverse joint is constructed using a full-elevation radial torsion surface modeling method based on the mid-surface geometry of the dam body, specifically including: Extract the upstream face curve of the crown arch and determine the control point position of the transverse joint on the upstream face curve of the crown arch based on the dam section design layout; The curve normal at the control point is calculated using the differential method, and a transverse seam positioning line segment is generated along this normal. Construct a vertical cutting plane along the elevation direction for the transverse joint positioning line segment, so that it intersects with the middle surface of the dam body, and obtain the transverse joint control points at each elevation position; Based on the mid-surface curves and corresponding transverse joint control points at each elevation location, the curve normal at the corresponding control point is calculated using the differential method, and the transverse joint positioning line segment at each elevation location is generated. The positioning line segments of the transverse joints at each elevation position are fitted along the elevation direction to form a full-elevation radial twisted transverse joint.

[0012] Furthermore, generating a structural influence zone entity with thickness based on the width of the structural influence zone includes: The spatial position of the structural surface relative to the dam coordinate system is determined based on the orientation, and the center plane of the structural surface is established based on the dip and inclination angle of the structural surface. The central plane of the structural surface is extended along the extension direction of the plane it is located in, and then cut within the target foundation area so that the central plane of the structural surface penetrates the terrain entity to be partitioned. Based on the width of the influence band of the structural surface, a bidirectional offset is made along the normal of the center plane of the structural surface to generate a solid structural surface influence band with thickness.

[0013] Furthermore, an interpolation fitting method was used to reconstruct the weathering layers.

[0014] Furthermore, the interpolation fitting method is implemented using the radial basis function interpolation method, including: Based on the weathering information obtained from the survey, control samples of the weathering layer depth are extracted, and a radial basis function interpolation model is constructed based on the weathering layer depth control samples to obtain the weathering layer depth function. Then, by combining the surface point cloud coordinates, the weathering layer is reconstructed based on the weathering layer depth values ​​corresponding to each surface point.

[0015] Furthermore, topological cutting and closure processing is performed on the foundation area; the interface intersection relationships are identified and solid cutting, boundary closure, and redundant volume removal are performed iteratively, including: Using the structural surface influence zone entity, the reconstructed weathered layer, and the closed excavation simulation terrain model as the boundary of the foundation area, the intersection relationship of the foundation entities to be divided is determined; for the target entities with intersection relationships, cutting processing is performed, and the open boundary formed after cutting is closed and reconstructed, and the redundant sub-entities generated by cutting are removed, thereby forming a closed geological zoning model.

[0016] Furthermore, the topology tidying includes: Based on the intersection relationships between the arch dam structure model, the foundation transition thin layer, the closed excavation simulation terrain model, the reconstructed weathered layer, and the structural surface influence zone entities, common intersection lines, contact boundary lines, and intersection surfaces between each model are extracted. Topological consistency processing is performed on common boundary lines and common boundary surfaces that overlap in spatial position between adjacent models, ensuring that adjacent partitions reference the same boundary line or the same boundary surface at the common boundary. Specifically, for common boundary lines, they are divided according to the same dividing points, ensuring that the number of segments, segment positions, and endpoint coordinates of corresponding boundary lines in adjacent partitions remain consistent. For common contact surfaces or intersection surfaces, the boundary contours and internal dividing line topologies of corresponding surfaces in adjacent partitions remain consistent. Open boundaries and redundant sub-entities formed by Boolean cutting, terrain excavation, and geological partitioning are identified, and boundary closure and redundant body removal are implemented. This results in an overall computational geometric model where common line segments are divided equally, common surface patches are bounded equally, and adjacent partitions have consistent topology.

[0017] Furthermore, the classification, extraction, and segmentation of various control lines include: The dam body's transverse arch line, longitudinal radial line, vertical line, orifice outline, transverse joint boundary line, and foundation thin layer boundary line are segmented at a smaller scale; the excavation boundary line, weathering boundary line, and structural surface control line are segmented at a medium scale; the foundation outer boundary line far from the dam body is segmented at a larger scale; and the fine grid of the dam body and the coarse grid of the foundation are coordinated and connected through the grid of the foundation thin layer, thus forming an overall three-dimensional finite element model of the arch dam and foundation.

[0018] On the other hand, the present invention provides an arch dam simulation analysis system based on topographic and geological reconstruction, comprising: The dam structure reconstruction module is used to construct a smooth arch dam model, determine the position of each flood discharge gate with the same radial center, and cut the smooth arch dam model to form dam body openings; construct radial twisted transverse joints that run through the entire elevation and transition thin layers on the foundation surface to obtain the arch dam structure model; The excavation simulation terrain reconstruction module is used to construct a foundation model based on terrain point cloud data, generate an excavation cutting model from the thin transition layer edge of the foundation surface according to the excavation control parameters, and form a closed excavation simulation terrain model through Boolean operations between the excavation cutting model and the foundation model. The geological zoning model construction module is used to extract the attitude information of structural planes for spatial positioning; generate a structural plane influence zone entity with thickness based on the width of the structural plane influence zone; reconstruct the weathering layer based on the weathering layer information; use the structural plane influence zone entity, the reconstructed weathering layer, and the closed excavation simulation terrain model as boundary constraints, and perform topological cutting and closure processing on the foundation area based on the closed excavation simulation terrain model; identify the interface intersection relationship and iteratively implement entity cutting, boundary closure, and redundant body removal to obtain the geological zoning model; The integrated assembly and mesh generation module is used to spatially register and integrate the arch dam structure model and the geological zoning model, and perform topological sorting to form an overall geometric model of the arch dam-foundation; it classifies, extracts, and segments various control lines; it generates dam body mesh, transition thin layer mesh, and foundation mesh based on the segmentation results, and achieves coordinated connection between the fine dam body mesh and the coarse foundation mesh through the transition thin layer unit; based on the geological attribute information corresponding to each geological zoning, it forms an overall three-dimensional finite element model of the arch dam-foundation that can be directly used for finite element solution, and can be solved after applying boundary conditions and loads to the model.

[0019] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention can simultaneously and precisely express the dam body details such as the dam body openings, transverse joints and the thin transition layer of the foundation surface. The transverse joints adopt the full elevation radial twist surface modeling method based on the geometry of the dam body mid-surface, which can more realistically reflect the joint arrangement characteristics of the dam section and the spatial stress form of the transverse joints, thereby improving the modeling accuracy of the arch dam details.

[0020] (2) By reconstructing the dam shoulder slope, excavated simulated terrain, weathered layer and structural surface, this invention can more realistically reflect the spatial zoning characteristics of the foundation area under complex terrain and geological conditions and the cutting and interpenetration relationship of different geological interfaces, thereby improving the realism of the terrain and geological model.

[0021] (3) This invention integrates the dam body fine structure, excavation simulation terrain and geological zoning model into a unified finite element analysis model, which overcomes the problem that dam body modeling, excavation modeling and geological zoning processing are independent in the prior art. It is beneficial to avoid inconsistent model boundaries, discontinuous calculation nodes, unclear zoning relationships and distorted analysis results.

[0022] (4) This invention implements differentiated segmented control of the key structural lines, excavation boundary lines and structural surface control lines of the dam body, and constructs a sparse and dense overall three-dimensional finite element mesh, which can ensure the analysis accuracy of key areas while taking into account the overall calculation efficiency.

[0023] (5) This invention realizes the fine simulation analysis of the arch dam-foundation system under real terrain and geological conditions, and can provide a more reliable analysis model and technical means for evaluating the stress, deformation and overall working performance of complex arch dam projects. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a flowchart of a method according to an embodiment of the present invention; Figure 2 A schematic diagram of the fine structural reconstruction method for arch dams; Figure 3 A schematic diagram of the transition thin layer construction method; Figure 4 A schematic diagram of the excavation and simulated terrain reconstruction method; Figure 5 A schematic diagram illustrating the method for topographic and geological reconstruction and the construction of an integrated dam-excavation-geology model; Figure 6A schematic diagram illustrating the grouping and segmentation method of the key control lines of the dam body and foundation; Figure 7 A schematic diagram is generated for the dam body, transverse joints, transition thin layers, and foundation surface mesh. Figure 8 Schematic diagram for assigning material parameters to a geological zoning model; Figure 9 This is a displacement cloud diagram for static analysis of the arch dam-foundation system according to the method of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] Example 1 like Figure 1 As shown, this embodiment provides a simulation analysis method for arch dams based on topographic and geological reconstruction, including the following steps: Step S1: Construct a smooth arch dam model, determine the location of each spillway opening with the same radial center, and cut the smooth arch dam model to form dam body openings; construct a radial twisted transverse joint that runs through the entire elevation and a thin transition layer on the foundation surface to obtain the arch dam structure model; Step S2: Construct a foundation model based on terrain point cloud data, and generate an excavation cutting model from the thin transition layer edge of the foundation surface according to the excavation control parameters; form a closed excavation simulation terrain model through Boolean operations between the excavation cutting model and the foundation model; Step S3: Extract the attitude information of the structural plane for spatial positioning; generate a structural plane influence zone entity with thickness based on the width of the structural plane influence zone; reconstruct the weathering layer based on the weathering layer information; using the structural plane influence zone entity, the reconstructed weathering layer, and the closed excavation simulation terrain model as boundary constraints, perform topological cutting and closure processing on the foundation area based on the closed excavation simulation terrain model; identify the interface intersection relationship and iteratively implement entity cutting, boundary closure, and redundant body removal to obtain the geological zoning model; Step S4: Spatial registration and integrated assembly of the arch dam structure model and the geological zoning model are performed, and topological sorting is carried out to form an overall geometric model of the arch dam-foundation; various control lines are classified, extracted, and segmented; based on the segmentation results, dam body mesh, transition thin layer mesh, and foundation mesh are generated respectively, and the coordination between the fine mesh of the dam body and the coarse mesh of the foundation is achieved through the transition thin layer unit; according to the geological attribute information corresponding to each geological zoning, including lithology, weathering grade, and structural surface influence zone type, corresponding material attribute parameters are assigned to form an overall three-dimensional finite element model of the arch dam-foundation that can be directly used for finite element solution; after applying boundary conditions and loads to the model, it can be solved.

[0028] This embodiment, based on actual arch dam design data from a hydropower project, conducts detailed structural reconstruction of the dam body, excavation simulation topography reconstruction, topographic and geological reconstruction, and construction and analysis of an integrated dam-excavation-geology model for a 300-meter-class high arch dam. The specific steps of the detailed simulation analysis method for arch dams based on topographic and geological reconstruction are as follows: Step S1: Fine-scale structural reconstruction of the arch dam body. An automated modeling method for quadratic curve arch dams is used to construct a smooth-surface arch dam model. The coordinate system is defined with the upstream vertex of the arch crown beam as... xOy plane origin O Pointing to the left bank in the direction across the river, pointing upstream in the direction along the river, and pointing vertically upward are respectively x , y , z The positive direction of the axis, z The zero point of the axis is located at the geoid. The orifice parameters are shown in Table 1.

[0029] Table 1. Modeling parameters for dam orifices

[0030] Based on the coordinates of the centerline of each orifice and the coordinates of the corresponding radial center of the orifice, the centerline of each orifice is generated parametrically; the orifice cutting column is constructed by extending along the preset orifice contour in the normal plane of each orifice centerline; then the orifice cutting column is subjected to Boolean difference operation with the smooth dam model to obtain a three-dimensional open dam model including the orifice structure of the dam body.

[0031] Based on the actual dam section joint layout design, the starting point for the transverse joint on the upstream arch curve of the dam crest is determined, and its corresponding arc length coordinate is: Starting from this point, according to the spacing The transverse joint placement points are determined sequentially along the arc length of the dam crest at intervals of 19.5m, 21m, and 22m. Let the first... i The coordinates of the deployment points are: And take the nearest neighboring point along the curve direction. Based on the differential approximation, the normal direction vector of this arrangement point in the horizontal plane can be obtained as follows: A transverse joint positioning line segment is constructed along the normal direction, and a corresponding vertical cutting surface is further generated. The intersection of this vertical cutting surface with the mid-surface of the dam body is used to obtain the transverse joint control intersection line. The intersection points on this line are the transverse joint control points at each elevation, used to determine the transverse joint control position at each elevation. Subsequently, the local normal direction is again obtained by differential approximation for the transverse joint control points at each elevation. Based on this, a transverse joint positioning line segment at the corresponding elevation is constructed, and it is laid out and fitted along the elevation direction, ultimately forming a radially twisted transverse joint that runs through the entire elevation, as shown below. Figure 2 As shown.

[0032] Based on the generated model of the dam body with openings and joints, the boundary contour of the dam body foundation surface is extracted and divided into the left bank side, right bank side, and bottom plane, as follows: Figure 3 As shown. The top and bottom structural lines of the left and right bank sides are extracted respectively. The outward normal of the left bank top structural line is... The outward normal of the left bank bottom structural line is Based on the above two outward normal weighted averages, the extension direction of the thin layer on the left bank is determined as follows: Its offset distance is 2 m. The outward normal of the right bank top structure line is... The outward normal of the right bank bottom structural line is Based on the above two outward normal weighted averages, the extension direction of the thin layer on the right bank is determined as follows: The offset distance is 2 m. At the same time, the bottom plane is offset downward by 2 m, and a triangular prism transition body is constructed to connect with the thin layers on the left and right banks, thereby forming a fine dam model of the arch dam that includes dam body openings, transverse joints and foundation transition structures.

[0033] Step S2: Employing a point cloud-based refined arch dam foundation model and excavation simulation method, a lightweight refined foundation model is first constructed based on topographic point cloud data. On this basis, combining excavation control parameters such as excavation direction, slope ratio, excavation length, ramp width, and the bottom elevation of the stilling basin, an excavation cutting model containing the excavated slope, stilling basin, and ramp is automatically generated from the thin transition layer edge of the self-built foundation surface. Then, through Boolean operations between the excavation cutting model and the refined foundation model, the excavated terrain and the simulated terrain are reconstructed, such as... Figure 4 As shown.

[0034] Step S3: First, extract the attitude information of the structural plane from the engineering plan view. Determine the spatial position of the structural plane relative to the dam coordinate system based on its orientation, and establish the center plane of the structural plane according to its dip and dip angle. Extend the center plane of the structural plane along the extension direction of its plane and trim it within the target foundation area so that the center plane of the structural plane penetrates the terrain entity to be partitioned. Then, based on the width of the influence zone of the structural plane, perform a bidirectional offset along the normal of the center plane of the structural plane to generate a structural plane influence zone entity with thickness. For ease of demonstration, this embodiment selects a representative structural plane F. 10 F 11 and Fd 112 The geometric shape of the influence zone of the structural plane can be reconstructed based on the input spatial location, dip, tilt angle and influence zone width information.

[0035] Based on the weathering layer thickness and spatial location information obtained from the survey, and combined with surface point cloud data, the weathering layer is reconstructed. Specifically, firstly, control sample points for the weathering layer depth are extracted from the survey data, denoted as the [missing information - likely a specific point or data point]. j The coordinates of the sample points are The corresponding surface elevation is Then the point corresponds to the thickness of the weathering layer. for

[0036] in, The first j sample points x , y , z Axis coordinates.

[0037] Based on the weathering layer depth control samples, a weathering layer depth function is constructed using the radial basis function interpolation method. The weathering layer depth function can represent

[0038] In the formula, N The number of sample points was controlled to determine the depth of the weathering layer; These are the interpolation coefficients to be determined; These are radial basis functions; These are low-order polynomial terms used to improve interpolation stability and overall fitting accuracy. The low-order polynomial term is taken as...

[0039] In the formula, a 0, a 1, a 2 represents an undetermined coefficient. The radial basis function... The function can be selected from quadratic functions, Gaussian functions, or thin-plate spline functions, depending on the actual needs. Here, we choose...

[0040] In the formula, r The interpolation point is the planar distance between the interpolation point and the control sample point. c For shape parameters.

[0041] By ensuring that the interpolation function satisfies the depth constraint conditions at all control sample points.

[0042] And combined with additional constraints

[0043] Find the interpolation coefficients and polynomial coefficients a 0, a 1, a 2. Thus, a weathering layer depth function is established. .

[0044] Furthermore, the weathering layers are reconstructed by combining the coordinates of the surface point cloud. Let the coordinates of any point in the surface point cloud be... Then the coordinates of the weathering layer reconstruction point corresponding to this point are: ,in

[0045] That is, based on the planar position of the surface point, its corresponding depth is obtained using the weathering layer depth function, and then the weathering layer point is obtained by vertically offset downwards. All reconstructed points are then... By performing surface fitting, a continuous weathering layer can be formed. Further, using the structural surface influence zone entity, weathering layer, and closed excavation simulation terrain as boundary constraints, topological cutting and closure processing are performed on the foundation area. The program automatically determines the intersection relationship between each interface and accordingly performs cyclical entity cutting, local closure repair, and redundant debris removal until a geological zoning model with complete boundaries and correct topological relationships is formed, such as... Figure 5 As shown.

[0046] Step S4: Construction and Analysis of the Integrated Dam-Excavation-Geological Model. To ensure the geometric continuity and topological consistency between the thin-layer structure and the dam and foundation models, the interfaces in contact with the foundation in the thin layer are cut in the same way as the foundation, while the remaining interfaces remain unchanged. After the cutting is completed, the thin layer assembly is sealed. Subsequently, the perforated and segmented dam model generated in Step S1, the excavation simulation terrain model generated in Step S2, and the geological zoning model generated in Step S3 are uniformly registered and integrated to form a comprehensive three-dimensional model including the dam body, excavation slope, weathered layer, structural surfaces, and stratigraphic zoning.

[0047] Further model topology refinement is performed. Based on the intersection relationships between the arch dam body model, the transition thin layer of the foundation surface, the excavation simulation terrain model, the weathered layer, and the structural surface influence zone entities, common intersection lines, contact boundary lines, and intersection surfaces between each model are extracted. Topological consistency processing is performed on the boundary lines and boundary surfaces that overlap in spatial position between adjacent models, so that adjacent partitions reference the same boundary line or the same boundary surface at the common boundary. Specifically, for the common boundary line, it is divided according to the same dividing point, so that the number of segments, segment positions, and endpoint coordinates of the corresponding boundary lines of adjacent partitions are consistent. For the common contact surface or intersection surface, the boundary contour and internal dividing line topology of the corresponding surface of adjacent partitions are consistent. Open boundaries and redundant sub-entities formed by Boolean cutting, terrain excavation, and geological partitioning are identified, and boundary closure and redundant body removal are implemented. This forms an overall computational geometry model with common line segments, common surface patches, and consistent topology between adjacent partitions, so that the subsequent finite element mesh has consistent node positions and element boundaries at the common boundary of adjacent partitions.

[0048] After model assembly and topology refinement, the key control lines of the dam body and foundation are classified, extracted, grouped, and segmented in a differentiated manner. In this embodiment, the key structural lines of the dam body mainly include the transverse arch line, the longitudinal radial line, the vertical control line, and the orifice outline control line. The transverse arch line controls the grid distribution along the arch direction of the dam body; the longitudinal radial line controls the grid transition along the upstream and downstream directions; the vertical control line ensures the grid continuity and interlayer correspondence along the elevation direction; and the orifice outline control line precisely describes the boundary morphology of complex local areas such as spillway orifices. By grouping and managing these structural lines, the grid density and grid generation rules in different directions can be controlled separately, thereby ensuring that the dam body grid is generally regular and orderly.

[0049] For critical foundation segments, the mesh density of excavation boundary lines, weathering boundaries, and structural surface control lines is generally lower than that of the dam body. For other foundation boundary segments, a coarser segmentation method is used to balance computational efficiency and accuracy. In this embodiment, the dam body's transverse arch line, longitudinal radial line, vertical line, orifice outline, transverse joint boundary line, and thin-layer boundary line of the foundation surface use a smaller segmentation scale, with an average mesh size of 6-7m; the excavation boundary line, weathering boundary line, and structural surface control line use a medium segmentation scale, with an average mesh size of 14-16m; and the outer foundation boundary lines far from the dam body use a larger segmentation scale, with an average mesh size of 40-50m. Figure 6 As shown. The final generated overall three-dimensional finite element mesh exhibits balanced density. The dam body mesh, transverse joint mesh, thin transition mesh near the dam face, thin transition mesh near the foundation, and foundation surface mesh are shown below. Figure 7 As shown.

[0050] Furthermore, corresponding material parameters are assigned based on the geological properties of each zone, such as... Figure 8 As shown in the figure, different colored grids correspond to different material properties, including elastic modulus, density, and Poisson's ratio, thus providing a material parameter basis for subsequent finite element analysis.

[0051] To verify the rationality and computational feasibility of the model constructed by the method of this invention, boundary normal displacement constraints and bottom full constraints were applied to the model. Taking normal water level and temperature drop conditions as an example, static solutions were performed by sequentially applying ground stress, gravity, upstream and downstream hydrostatic pressure, silt pressure, uplift pressure, and temperature load, resulting in a total displacement contour map, as shown below. Figure 9 As shown. By Figure 9 It can be seen that the maximum total displacement of the dam body is approximately 11 cm. The displacement distribution pattern is consistent with the understanding gained from engineering practice, indicating that the calculation model constructed by the method of this invention has good rationality and computability, and can realize the fine finite element simulation analysis and result output of the arch dam-foundation system. It should be understood that all parts not described in detail in this specification belong to the prior art.

[0052] Example 2 This embodiment provides an arch dam simulation analysis system based on topographic and geological reconstruction, including: The dam structure reconstruction module is used to construct a smooth arch dam model, determine the position of each flood discharge gate with the same radial center, and cut the smooth arch dam model to form dam body openings; construct radial twisted transverse joints that run through the entire elevation and transition thin layers on the foundation surface to obtain the arch dam structure model; The excavation simulation terrain reconstruction module is used to construct a foundation model based on terrain point cloud data, generate an excavation cutting model from the thin transition layer edge of the foundation surface according to the excavation control parameters, and form a closed excavation simulation terrain model through Boolean operations between the excavation cutting model and the foundation model. The geological zoning model construction module is used to extract the attitude information of structural planes for spatial positioning; generate a structural plane influence zone entity with thickness based on the width of the structural plane influence zone; reconstruct the weathering layer based on the weathering layer information; use the structural plane influence zone entity, the reconstructed weathering layer, and the closed excavation simulation terrain model as boundary constraints, and perform topological cutting and closure processing on the foundation area based on the closed excavation simulation terrain model; identify the interface intersection relationship and iteratively implement entity cutting, boundary closure, and redundant body removal to obtain the geological zoning model; The integrated assembly and mesh generation module is used to spatially register and integrate the arch dam structure model and the geological zoning model, and perform topological sorting to form an overall geometric model of the arch dam-foundation. It classifies, extracts, and segments various control lines; generates dam body mesh, transition thin layer mesh, and foundation mesh based on the segmentation results, and achieves coordinated connection between the fine dam body mesh and the coarse foundation mesh through transition thin layer units; and assigns corresponding material property parameters according to the lithology, weathering grade, and structural surface influence zone type of each geological zoning, forming an overall three-dimensional finite element model of the arch dam-foundation that can be directly used for finite element solution. After applying boundary conditions and loads to the model, it can be solved.

[0053] It should be understood that the above description of the preferred embodiments is quite detailed, but this should not be construed as limiting the scope of protection of this invention. It is neither necessary nor possible to exhaustively describe all possible implementations. Those skilled in the art, guided by this invention, can make substitutions or modifications without departing from the scope of the claims, all of which fall within the scope of protection of this invention. The scope of protection of this invention should be determined by the appended claims.

Claims

1. A simulation analysis method for arch dams based on topographic and geological reconstruction, characterized in that, Includes the following steps: A smooth arch dam model was constructed. The positions of each spillway opening were determined with the same radial center. The smooth arch dam model was then cut to form openings in the dam body. A radial twisted transverse joint and a thin transition layer on the foundation surface were constructed to obtain the arch dam structure model. A foundation model is constructed based on topographic point cloud data, and an excavation cutting model is generated from the thin transition layer edge of the foundation surface according to the excavation control parameters; a closed excavation simulation terrain model is formed through Boolean operations between the excavation cutting model and the foundation model. Extract the attitude information of the structural plane for spatial positioning; generate a structural plane influence zone entity with thickness based on the width of the structural plane influence zone; reconstruct the weathered layer based on the weathered layer information; and perform topological cutting and closure processing on the foundation area based on the closed excavation simulation terrain model, using the structural plane influence zone entity, the reconstructed weathered layer, and the closed excavation simulation terrain model as boundary constraints. The geological zoning model is obtained by identifying the intersection relationships of interfaces and iteratively performing entity cutting, boundary closure and redundant body removal. The arch dam structure model and the geological zoning model are spatially registered and integrated, and topologically processed to form an overall geometric model of the arch dam and foundation. Various control lines are classified, extracted, and segmented. Based on the segmentation results, dam body mesh, transition thin layer mesh, and foundation mesh are generated respectively, and the coordination between the fine dam body mesh and the coarse foundation mesh is achieved through the transition thin layer unit. According to the geological attribute information corresponding to each geological zoning, the corresponding material attribute parameters are assigned to form an overall three-dimensional finite element model of the arch dam and foundation that can be directly used for finite element solution. After applying boundary conditions and loads to the model, it can be solved.

2. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, The locations of each spillway opening are determined using the same radial center, and the smooth dam model of the arch dam is cut to form the dam body openings, including: Determine the coordinates of the radial center point of the dam's spillway gate and construct the gate's column cutting body; Boolean cutting was performed on the smooth arch dam model using the aforementioned orifice column cutting body to form an open structure in the dam body; Among them, the flood discharge outlets of each dam body at the same central elevation adopt the same radial center and are arranged radially along the radial center.

3. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, The radial twisted surface transverse joint is constructed using a full-elevation radial twisted surface modeling method based on the mid-surface geometry of the dam body, specifically including: Extract the upstream face curve of the crown arch and determine the control point position of the transverse joint on the upstream face curve of the crown arch based on the dam section design layout; The curve normal at the control point is calculated using the differential method, and a transverse seam positioning line segment is generated along this normal. Construct a vertical cutting plane along the elevation direction for the transverse joint positioning line segment, so that it intersects with the middle surface of the dam body, and obtain the transverse joint control points at each elevation position; Based on the mid-surface curves and corresponding transverse joint control points at each elevation location, the curve normal at the corresponding control point is calculated using the differential method, and the transverse joint positioning line segment at each elevation location is generated. The positioning line segments of the transverse joints at each elevation position are fitted along the elevation direction to form a full-elevation radial twisted transverse joint.

4. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, Generating a structural influence zone entity with thickness based on the width of the structural influence zone includes: The spatial position of the structural surface relative to the dam coordinate system is determined based on the orientation, and the center plane of the structural surface is established based on the dip and inclination angle of the structural surface. The central plane of the structural surface is extended along the extension direction of the plane it is located in, and then cut within the target foundation area so that the central plane of the structural surface penetrates the terrain entity to be partitioned. Based on the width of the influence band of the structural surface, a bidirectional offset is made along the normal of the center plane of the structural surface to generate a solid structural surface influence band with thickness.

5. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, The weathering layers were reconstructed using an interpolation fitting method.

6. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 5, characterized in that, The interpolation fitting method is implemented using the radial basis function interpolation method, including: Based on the weathering information obtained from the survey, control samples of the weathering layer depth are extracted, and a radial basis function interpolation model is constructed based on the weathering layer depth control samples to obtain the weathering layer depth function. Then, by combining the surface point cloud coordinates, the weathering layer is reconstructed based on the weathering layer depth values ​​corresponding to each surface point.

7. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, Perform topological cutting and closure on the foundation area; Identifying interface intersections and iteratively performing entity cutting, boundary closure, and redundant volume removal includes: Using the structural surface influence zone entity, the reconstructed weathered layer, and the closed excavation simulation terrain model as the foundation area partition boundary, the intersection relationship of the foundation entities to be partitioned is determined. For target entities with intersecting relationships, a cutting process is performed, and the open boundaries formed after the cutting are closed and reconstructed. Then, redundant sub-entities generated by the cutting are removed, thereby forming a closed geological zoning model.

8. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, The topology simplification includes: Based on the intersection relationships between the arch dam structure model, the foundation transition thin layer, the closed excavation simulation terrain model, the reconstructed weathered layer, and the structural surface influence zone entities, common intersection lines, contact boundary lines, and intersection surfaces between each model are extracted. Topological consistency processing is performed on common boundary lines and common boundary surfaces that overlap in spatial position between adjacent models, ensuring that adjacent partitions reference the same boundary line or the same boundary surface at the common boundary. Specifically, for common boundary lines, they are divided according to the same dividing points, ensuring that the number of segments, segment positions, and endpoint coordinates of corresponding boundary lines in adjacent partitions remain consistent. For common contact surfaces or intersection surfaces, the boundary contours and internal dividing line topologies of corresponding surfaces in adjacent partitions remain consistent. Open boundaries and redundant sub-entities formed by Boolean cutting, terrain excavation, and geological partitioning are identified, and boundary closure and redundant body removal are implemented. This results in an overall computational geometric model where common line segments are divided equally, common surface patches are bounded equally, and adjacent partitions have consistent topology.

9. The method for simulation analysis of arch dams based on topographic and geological reconstruction according to claim 1, characterized in that, The classification, extraction, and segmentation of various control lines include: The dam body's transverse arch line, longitudinal radial line, vertical line, orifice outline, transverse joint boundary line, and foundation thin layer boundary line are segmented at a smaller scale; the excavation boundary line, weathering boundary line, and structural surface control line are segmented at a medium scale; the foundation outer boundary line far from the dam body is segmented at a larger scale; and the fine grid of the dam body and the coarse grid of the foundation are coordinated and connected through the grid of the foundation thin layer, thus forming an overall three-dimensional finite element model of the arch dam and foundation.

10. A simulation analysis system for arch dams based on topographic and geological reconstruction, characterized in that, include: The dam structure reconstruction module is used to construct a smooth arch dam model, determine the position of each flood discharge gate with the same radial center, and cut the smooth arch dam model to form dam body openings; construct radial twisted transverse joints that run through the entire elevation and transition thin layers on the foundation surface to obtain the arch dam structure model; The excavation simulation terrain reconstruction module is used to construct a foundation model based on terrain point cloud data, generate an excavation cutting model from the thin transition layer edge of the foundation surface according to the excavation control parameters, and form a closed excavation simulation terrain model through Boolean operations between the excavation cutting model and the foundation model. The geological zoning model construction module is used to extract the attitude information of the structural plane for spatial positioning; generate a structural plane influence zone entity with thickness based on the width of the structural plane influence zone; reconstruct the weathering layer based on the weathering layer information; and perform topological cutting and closure processing on the foundation area based on the closed excavation simulation terrain model, using the structural plane influence zone entity, the reconstructed weathering layer, and the closed excavation simulation terrain model as boundary constraints. The geological zoning model is obtained by identifying the intersection relationships of interfaces and iteratively performing entity cutting, boundary closure and redundant body removal. The integrated assembly and mesh generation module is used to spatially register and integrate the arch dam structure model and the geological zoning model, and perform topological sorting to form an overall geometric model of the arch dam-foundation; it classifies, extracts, and segments various control lines; it generates dam body mesh, transition thin layer mesh, and foundation mesh based on the segmentation results, and achieves coordinated connection between the fine dam body mesh and the coarse foundation mesh through the transition thin layer unit; it assigns corresponding material property parameters according to the geological attribute information corresponding to each geological zoning, forming an overall three-dimensional finite element model of the arch dam-foundation that can be directly used for finite element solution; and it can be solved after applying boundary conditions and loads to the model. The arch dam simulation analysis system based on topographic and geological reconstruction is used to perform the steps in the arch dam simulation analysis method based on topographic and geological reconstruction as described in any one of claims 1 to 9.

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