Disaster-oriented inversion of tectonic line element transmission tower rapid modeling method and system

Abstract

The application discloses a kind of structural line element transmission tower fast modeling methods and systems for disaster inversion, method includes: S1 transmission tower structure feature split and parameterized feature definition;S2 transmission tower global coordinate system establishment and node coordinate analytical calculation;S3 based on straight line segment line element transmission tower modular modeling;S4 transmission tower voxel model grid division, unit and cross section attribute and direction assignment;S5 transmission tower model optimization and geometric quality check.The application is realized by standardization line segment base element, parameterization drive and Boolean operation combination, and the rapid construction of transmission tower three-dimensional geometric model is greatly improved modeling efficiency and model reusability, for the technical problem of transmission tower model fast generation under earthquake disaster scene provides a kind of solution.

Description

Technical Field

[0001] This invention belongs to the field of engineering structure simulation and power grid disaster prevention and mitigation technology, specifically involving a rapid modeling method and system for structural element transmission towers oriented towards disaster inversion. Background Technology

[0002] With its wide coverage and long transmission line spans, the power grid has a large number of transmission towers erected in high-intensity earthquake zones and geologically complex areas. Seismic forces can easily cause buckling of members, failure of nodes, or even complete collapse of the transmission tower structure, leading to regional power grid paralysis. Conducting seismic response analysis, seismic performance assessment, and seismic disaster simulation of transmission towers is a key technical support for improving the seismic resilience of the power grid and ensuring the safe operation of the power system. High-precision and high-efficiency three-dimensional modeling methods are the core prerequisite for the above analysis and assessment work.

[0003] Current transmission tower modeling mainly relies on traditional CAD modeling and manual finite element modeling, which has significant shortcomings: On the one hand, transmission towers are composed of a large number of members such as angle steel and steel pipes, with complex structural forms and numerous nodes. Manual modeling requires defining the coordinates, cross-sectional properties, and connection relationships of each member, resulting in long modeling cycles and a large amount of repetitive work. On the other hand, the structures of transmission towers of different voltage levels and different tower types, such as the T-shaped, cat-head-shaped, and goblet-shaped towers, vary significantly. Traditional methods are difficult to use for rapid modification and batch generation of models. When multi-condition and multi-parameter earthquake disaster simulations are required, the model reconstruction efficiency is extremely low.

[0004] While existing parametric modeling techniques have improved modeling efficiency to some extent, they mostly focus on single components or simple frames, failing to modularize and extract features from the typical structural features of transmission towers, such as the tower body, tower legs, and tower head. This results in unclear representation of model topology relationships, making it difficult to adapt to the rapid reconstruction needs of complex tower types. Furthermore, dedicated modeling methods for power grid seismic hazards generally lack standardized line element combination rules and parameter-driven mechanisms. The coupling between the model and seismic response analysis and vulnerability calculation is poor, failing to meet the engineering application requirements for rapid early warning and seismic optimization design of power grid seismic hazards.

[0005] The constructive line element geometry method builds complex models using basic line elements and Boolean operations. It boasts advantages such as simple data structure, convenient modification, and complete geometric information, and has been applied in fields such as mechanical and architectural design. However, a standardized parametric modeling system adapted to power grid seismic disaster scenarios and the structural characteristics of transmission towers has not yet been established. Therefore, there is a need to develop a method based on constructive line elements, driven by feature parameters, that can rapidly generate high-precision transmission tower models. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a rapid modeling method and system for transmission towers. Based on the constructive line element geometry method and parametric modeling theory, it achieves rapid batch generation of three-dimensional transmission tower models through the construction of linear line element units, modular parameter driving, and Boolean operations. This efficiently supports seismic response analysis, vulnerability assessment, and seismic toughness assessment of transmission towers.

[0007] To achieve the above-mentioned technical objectives, the present invention employs the following technical means:

[0008] A rapid modeling method for transmission towers based on structural elements for disaster inversion, comprising the following steps:

[0009] S1. Transmission Tower Structural Feature Decomposition and Parametric Feature Definition: The overall structure of the transmission tower is decomposed into hierarchical features to establish a parametric feature system that includes size feature parameters and location feature parameters.

[0010] S2. Establishment of global coordinate system and analytical calculation of node coordinates of transmission tower: Based on the global coordinate system, according to the size characteristic parameters defined in step S1, establish the analytical calculation formula of the main material node coordinates, and solve the spatial coordinates of the node in batches through the accumulation of floor height and symmetric mapping.

[0011] S3. Modular modeling of transmission tower based on straight line segment elements: Based on the spatial coordinates of the nodes obtained in step S2, first establish a core load-bearing frame composed of main materials, then add cross diaphragms and inter-section cross auxiliary materials on the basis of the core load-bearing frame. Utilize the central symmetry, and generate tower legs, tower body and crossarm structure by mirroring the quarter structure through coordinate transformation. Then, give a unique identifier to the generated straight line segment elements to obtain the initial geometric model of transmission tower elements.

[0012] S4. Mesh generation, element and section attribute assignment, and orientation assignment of the initial transmission tower line element geometric model: Based on the initial transmission tower line element geometric model obtained in step S3, the model is meshed, element types are assigned, section attributes are defined, and the orientation of the angle steel members is calibrated. The orientation calibration includes: for beam element members, based on the tangent vector of the straight line segment element and the reference plane normal vector determined based on any edge line of the angle steel section, the unique local spatial coordinate system of the beam element is automatically determined through vector cross product operation, so as to uniquely determine the spatial orientation of the beam element. Through the above process, it is transformed into a transmission tower finite element model with the ability to perform mechanical analysis for earthquake disaster simulation.

[0013] S5. Geometric quality verification and output of transmission tower model: Perform geometric simplification and quality check on the finite element model of the transmission tower obtained in step S4, and finally output a geometrically accurate finite element model of the transmission tower that can be directly used for seismic response analysis.

[0014] Furthermore, step S1 specifically includes the following sub-steps:

[0015] S11. The transmission tower is divided into three major modules: tower body, tower legs, and tower head. The tower body is regarded as a multi-layered regular square truncated pyramid, the tower legs are regarded as four triangular pyramids, and the tower head is further divided into tower head body, crossarm, and ground wire support sub-modules.

[0016] S12. Define dimensional characteristic parameters: width of the base of the tower. Top layer width Total number of floors in the tower Each floor height Where i is the floor number; the tower leg height Tower leg root opening The dimensional characteristics of the crossarm include: crossarm length, end width, and layer height.

[0017] S13. Define positional characteristic parameters: module installation layer number, inter-section type number, and transverse diaphragm arrangement position LRef, to determine the position of the substructure in the whole in the form of sequence number.

[0018] Furthermore, step S2 includes the following sub-steps:

[0019] S21. Establish a global coordinate system: the origin O (0,0,0) is the center of the bottom surface of the tower, the Z-axis is vertically upward, and the X and Y axes are horizontally distributed;

[0020] S22. Calculate the coordinates of the nodes between the tower leg and the main material of the tower body:

[0021] The coordinates of the i-th node on the edge of the tower leg and the tower body are calculated using the following formula:

[0022] ;

[0023] in, x-axis coordinates of the nodes For the y-axis coordinate of the node, The z-axis coordinate of the node For the width of the base of the tower, For the width of the top layer of the tower, The total number of stories in the tower and the height of each story are: , where i is the layer number; k is the current layer number of the tower leg or tower body being calculated;

[0024] S23. Utilizing central symmetry, the coordinates of all nodes on the other three edges can be directly mapped from the coordinates of the nodes on the first quadrant edge.

[0025] Furthermore, step S3 specifically includes the following sub-steps:

[0026] S31. Modeling the basic framework of the tower body: Traverse the node coordinate array, use the spatial line feature modeling method to connect adjacent layer nodes on the same edge in sequence, generate the main material straight line segment line element, and form the four-sided frustum framework of the tower body.

[0027] S32. Tower body diaphragm modeling: Take the corresponding layer nodes according to the location number LRef, connect them in sequence to form a square outer frame, and use the central symmetry of the distribution of the internal components of the diaphragm to generate internal rods, thus completing the diaphragm line element modeling.

[0028] S33. Intersection Cross Modeling: Taking a single side as a reference, first calculate the intersection point of the line elements of the two intersecting diagonal lines, generate the line elements of the intersecting diagonal straight line segments, and then symmetrically generate the intersection structure of the other three sides.

[0029] S34. Tower Leg Modeling: Based on the bottom nodes of the tower body, model the tower legs according to their height. With the base of the tower leg Generate a triangular pyramid frame, and then arrange inter-segmental intersecting line elements on the three sides respectively;

[0030] S35. Tower head modeling: Reuse the tower body modeling logic to sequentially build the tower head body, crossarm, and ground wire support. The crossarm is treated as a pentahedron or hexahedron, and line segment elements are generated according to the node coordinates.

[0031] Furthermore, step S5 specifically includes the following sub-steps:

[0032] S51. Geometric quality verification: The key dimensions of the transmission tower line element model are checked, including tower height, tower leg root opening, crossarm length, and crossarm height. The error is controlled within the preset threshold range. For nodes where multiple components intersect, the endpoints of all line elements are traversed.

[0033] S52. Model Output: Output the verified transmission tower line element model as a three-dimensional mechanical model, retaining the line element information and node coordinate data, to provide a basis for subsequent seismic resilience analysis of power grid structure.

[0034] This invention further discloses a rapid modeling system for structural line element transmission towers for disaster inversion, comprising:

[0035] The parameterized feature definition module is used to perform hierarchical feature decomposition on the overall structure of the transmission tower and establish a parameterized feature system that includes size feature parameters and location feature parameters.

[0036] The node coordinate analysis and calculation module is used to establish the coordinate analysis and calculation formula of the main material node based on the global coordinate system and the size feature parameters defined by the parameterized feature definition module. It solves the spatial coordinates of the node in batches through the accumulation of floor height and symmetric mapping.

[0037] The modular modeling module is used to solve the node spatial coordinates obtained by the node coordinate analytical calculation module. First, a core bearing frame composed of main materials is established. Then, cross diaphragms and inter-section cross auxiliary materials are added on the basis of the core bearing frame. The tower legs, tower body and crossarm structure are generated by mirroring the quarter structure through coordinate transformation using central symmetry. The generated straight line segments are uniquely identified to obtain the initial transmission tower line element geometric model.

[0038] The attribute assignment and mesh generation module is used to perform mesh generation, element type assignment, section attribute definition and angle steel member orientation calibration based on the initial transmission tower line element geometric model, so as to give it mechanical properties equivalent to the actual model and transform it into a transmission tower finite element model that can be directly used for earthquake disaster simulation.

[0039] The quality verification and output module is used to perform geometric simplification and quality checks on the finite element model of the transmission tower, ensuring that the line element combination relationship conforms to the actual structural connection, and finally outputting a geometrically accurate final finite element model of the transmission tower that can be directly used for seismic response analysis.

[0040] Furthermore, the parameterized feature definition module is specifically used to: divide the transmission tower into three major modules: tower body, tower leg, and tower head. The tower body is regarded as a multi-layered regular square truncated pyramid, the tower leg is regarded as four triangular pyramids, and the tower head is further divided into tower head body, crossarm, and ground wire support sub-modules.

[0041] Define dimensional characteristic parameters: width of the base of the tower. Top layer width Total number of floors Each floor height Where i is the floor number; the tower leg height Tower leg root opening The dimensional characteristics of the crossarm include, but are not limited to: crossarm length, end width, and layer height.

[0042] Define location characteristic parameters: module installation layer number, inter-section type number, and transverse diaphragm arrangement position LRef. The node coordinate analysis and calculation module uses the following formula to calculate the node coordinates:

[0043] ;

[0044] in, x-axis coordinates of the nodes For the y-axis coordinate of the node, The z-axis coordinate of the node For the width of the base of the tower, For top layer width, The total number of floors and the height of each floor are... , where i is the layer number; k is the current layer number of the tower leg or tower body being calculated.

[0045] Furthermore, the modular modeling module is specifically used for: tower body diaphragm modeling: taking the corresponding layer nodes according to the position number LRef, connecting them in sequence to form a square outer frame, generating the internal members of the diaphragm according to the central symmetry method, and completing the diaphragm line element modeling;

[0046] Inter-segment cross modeling: Taking a single side as a reference, first calculate the intersection point of the line elements of the two intersecting diagonal lines, generate the line elements of the intersecting diagonal straight line segments, and then symmetrically generate the inter-segment structure of the other three sides.

[0047] Tower leg modeling: Based on the bottom nodes of the tower body, model according to the tower leg height. With the base of the tower leg Generate a triangular pyramid frame, and then arrange inter-segmental intersecting line elements on the three sides respectively;

[0048] Tower head modeling: Reuse the tower body modeling logic to sequentially build the tower head body, crossarm, and ground wire support. The crossarm is treated as a pentahedron or hexahedron respectively, and line segment elements are generated according to the node coordinates.

[0049] Furthermore, the attribute assignment and mesh generation module is specifically used for: automatically completing mesh generation in general finite element software by arranging mesh seeds on line segment elements and setting seed spacing parameters; defining and assigning component section attributes, and realizing batch creation and assignment of sections through loop scripts; assigning truss elements or beam elements to different types of components according to component analysis requirements; for beam element components, automatically determining the unique local spatial coordinate system of the beam element through vector cross product operation based on the tangent vector of the line segment element and the normal vector of the reference plane, realizing spatial orientation calibration of the beam element, wherein the normal vector of the reference plane is determined according to the straight line on any wing edge line of the angle steel section.

[0050] The present invention further discloses a computer-readable storage medium storing a computer program or instructions thereon, wherein the computer program or instructions, when executed by a processor, implement the steps of the method for rapid modeling of transmission towers for disaster inversion.

[0051] Compared with the prior art, the present invention has the following advantages:

[0052] First, modeling efficiency and parametric-driven capabilities are significantly improved:

[0053] This invention establishes a hierarchical parameter feature system (size parameters + position parameters) in step S1, combined with the analytical coordinate formula in step S2 and the "quarter-modeling, overall mirroring" strategy implemented in step S3 using the structural center symmetry. Compared with traditional CAD or manual finite element modeling, the modeling speed is increased by several times, and only a few feature parameters need to be modified to complete the rapid reconstruction of models of different tower types and sizes. It is particularly suitable for the needs of multi-condition and multi-parameter batch simulation in power grid seismic disaster inversion.

[0054] Second, the construction of line elements and modular combinations ensures geometric accuracy and topological correctness:

[0055] This invention uses straight line segments as basic units. Through clearly defined rules for calculating node coordinates and a modular assembly sequence (main frame → transverse diaphragm → inter-segment intersection → tower leg → tower head), it ensures that all members are connected by nodes, eliminating wandering line elements or unexpected interference. The geometric quality verification in step S5 further eliminates isolated line elements and duplicate segments. The final output finite element model of the transmission tower is geometrically accurate, with connection relationships conforming to the actual structure, and can be directly used for seismic response analysis.

[0056] Third, batch assignment of mechanical properties and orientation calibration enables efficient conversion from geometric models to finite element models: Step S4 automates mesh generation, section property assignment, and element type assignment by placing mesh seeds on line segment elements, creating cross sections in batches using a loop script, and batch specifying element types in a component set. Particularly for beam element components, the driven vector is calculated by the cross product of the tangent vector and the reference plane normal vector, accurately calibrating the spatial orientation of angle steel components. This gives the line element model mechanical properties comparable to the actual structure, eliminating the need for manual adjustments and significantly improving preprocessing efficiency.

[0057] Fourth, the specialization and engineering applicability of the technology for disaster inversion scenarios:

[0058] This invention was designed from the outset to meet the needs of earthquake disaster inversion. All parametric features, modular decomposition, and attribute assignments take into account the practical engineering scenario of generating large batches of transmission tower models rapidly. By modifying parameters, serialized modeling with different story heights and widths can be achieved for the same tower type. It also supports rapid switching between different tower types (such as T-shaped, cat-head-shaped, and goblet-shaped), and can efficiently support the seismic response analysis, vulnerability assessment, and seismic toughness assessment of transmission towers.

[0059] In summary, this invention is superior to existing technologies in terms of modeling speed, parametric capability, geometric accuracy, and degree of automation in assigning mechanical properties. Attached Figure Description

[0060] Figure 1 A schematic diagram of the tower structure and characteristic parameters of an example power tower;

[0061] Figure 2 This is a schematic diagram showing the location distribution of the main edges of an example power tower.

[0062] Figure 3 A flowchart of the algorithm for calculating the coordinates of the corner points of the main tower structure;

[0063] Figure 4 A schematic diagram of the tower frame created for the script;

[0064] Figure 5 This is a diagram illustrating the five types of horizontal partitions included in a script program;

[0065] Figure 6 A schematic diagram showing the key node positions of the SeptumType1 type diaphragm;

[0066] Figure 7 These are schematic diagrams of the six tower sections included in the script program;

[0067] Figure 8 A schematic diagram of the tower leg structure and characteristic parameters of an example power tower;

[0068] Figure 9 This is a schematic diagram of the tower head module and characteristic parameters for an example of a power tower.

[0069] Figure 10 A schematic diagram of the pentahedral crossarm model and characteristic parameters for an example of an electric tower;

[0070] Figure 11 A schematic diagram of the hexahedral crossarm model and characteristic parameters for an example of an electric tower;

[0071] Figure 12 A flowchart for the algorithm to establish the four edges of a pentahedron;

[0072] Figure 13 Flowchart of the algorithm for batch specifying section types for traversing a Set of components;

[0073] Figure 14 A schematic diagram showing the determination of the reference plane and local coordinate system for the beam element;

[0074] Figure 15 The flowchart of the algorithm for checking the spacing error of intersecting nodes to merge nodes;

[0075] Figure 16 This is a schematic diagram of the power tower model obtained by constructing a parametric modeling method using line elements. Detailed Implementation

[0076] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0077] The rapid modeling method for structural line element transmission towers oriented to disaster inversion of the present invention realizes the rapid construction of a three-dimensional geometric model of the transmission tower through standardized line elements, parametric driving and Boolean operation combination, comprising the following steps:

[0078] S1. Splitting of structural features of the transmission tower and definition of parametric features: Perform hierarchical feature decomposition on the overall structure of the transmission tower, and divide the transmission tower into secondary structures and reusable substructures. At the same time, a complete parametric feature system is established to define dimensional feature parameters and position feature parameters respectively;

[0079] S2. Establishment of the global coordinate system of the transmission tower and analytical calculation of node coordinates: Taking the global coordinate system as the reference, according to the dimensional feature parameters defined in step (1), the analytical calculation formula for the coordinates of the main material nodes is established, and the spatial coordinates of the nodes are solved in batches through methods such as story height accumulation and symmetric mapping;

[0080] S3. Modular modeling of transmission towers based on straight line segment elements: First, the core load-bearing frame composed of main materials is established, then structures such as diaphragms and inter-panel crosses are added on the basis of the frame. Using symmetry, complex structures such as diaphragms and cross arms are simplified into quarter units for modeling and then mirrored to generate the whole, and a Set collection is created to uniquely identify the straight line segment elements;

[0081] S4. Meshing of the transmission tower line element model, assignment of element and section attributes and directions: Based on the completed transmission tower model, meshing of the model, assignment of element types, definition of section attributes and direction calibration of angle steel members are carried out, so that the geometric model is transformed into a finite element model that can be directly used for seismic disaster simulation;

[0082] S5. Geometric quality verification and output of the transmission tower model: Geometric simplification and quality inspection are performed on the completed overall model, and finally a transmission tower line element model with accurate geometry that can be directly used for seismic response analysis is output.

[0083] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings of the specification and specific embodiments. This embodiment takes a certain dry-type straight transmission tower as the object, based on the Abaqus platform combined with Python scripts, adopts the parametric reconstruction method of the structural line element transmission tower model oriented to seismic disaster according to the present invention, and completes the three-dimensional geometric modeling of the transmission tower through line element combination, so as to provide reliable model support for the subsequent seismic disaster simulation analysis of the power grid.

[0084] The specific implementation process of the splitting of structural features of the transmission tower and the definition of parametric features described in step S1 combined with the example is as follows:

[0085] S11. Structural hierarchy splitting: The overall transmission tower is split into three major modules: tower body, tower leg and tower head.

[0086] Tower body: Multi-layered square pyramidal structure, composed of main frame, diaphragms, and inter-sections;

[0087] Tower legs: 4 symmetrical triangular pyramidal structures, composed of the main frame and intersecting side sections;

[0088] Tower head: It is divided into tower head body, crossarm, and ground wire support sub-module.

[0089] S12, Parameter Definition:

[0090] Dimensional characteristic parameters: width of the base of the tower Top layer width Total number of floors Each floor height Tower leg height Tower leg root opening Tower head section height, crossarm length, end width, and layer height;

[0091] Location characteristic parameters: diaphragm layer number LRef, inter-segment crossing type number, crossarm installation layer number.

[0092] The specific implementation process of establishing the global coordinate system of the transmission tower and performing analytical calculations and examples in step S2 is as follows:

[0093] S21 establishes a global Cartesian coordinate system with the center of the tower's base as the origin O (0,0,0). The Z-axis points vertically upward, and the central axis of the tower coincides with the Z-axis. The structure is symmetrical about the Z-axis.

[0094] S22. In the real-world scenario of building a transmission tower, the main materials constitute the basic framework of the transmission tower. When building a transmission tower model, the basic main material framework should be considered first.

[0095] The tower structure is shown in the attached figure. Figure 1 As shown, the tower body is a regular square truncated pyramid structure; therefore, the dimensional characteristic parameter of the tower body is the width of the bottom layer. Top layer width Total number of floors in the tower and the floor height between each section Simultaneously, the base point of the entire tower body coincides with the origin. Based on the dimensional characteristic parameters, the coordinates of the quadrangular frustum projected onto edge 1 in the first quadrant of the xy plane are calculated. Due to symmetry, the coordinates of the other three edges can then be derived. Figure 2 The location distribution of the four main edges of the transmission tower is shown. The formula for calculating the coordinates of the i-th point on edge 1 is as follows:

[0096]

[0097] S23. Based on the above formula, the coordinates of the corner points on the four edges of each layer can be calculated iteratively according to the dimensional parameters. A three-dimensional array storing the coordinates of all corner points on the basic frame is calculated and returned. The relevant algorithm flowchart is attached. Figure 3 .

[0098] The specific implementation process of modular modeling and instance combination of transmission tower based on straight line segment elements described in step S3 is as follows:

[0099] S31. Basic Frame Modeling of the Tower: Based on the spatial coordinates of the main material nodes obtained in step S2, the WirePolyLine method is called cyclically in a certain order. That is, the second and third dimensions of the three-dimensional array bodybasenode are traversed, and the WirePolyLine method is used to connect the corner points of the i-th layer and the corner points of the (i+1)-th layer on each edge to obtain the tower frame, as shown in the attached figure. Figure 4 As shown.

[0100] Note: In this embodiment, the "WirePolyLine method" mentioned in step S31 refers to: obtaining the spatial three-dimensional coordinates of each key node of the transmission tower, and using a spatial polyline generation algorithm based on point set sequences to sequentially connect the nodes in the preprocessing environment to generate spatial line features for subsequent assignment of beam element attributes. It should be understood that WirePolyLine is only a specific function implementation in this embodiment on the Abaqus platform. Similar spatial polyline or node connection commands can be used in other finite element or CAD platforms to achieve the same technical effect.

[0101] Note: Since the Abaqus platform typically uses Beam or Truss elements to model slender members, this simplification is acceptable from a mechanical analysis perspective. When modeling Beam or Truss elements, Abaqus first uses 3D line elements for spatial positioning. Subsequently, different member cross-sections are set in Beam or Truss elements in different regions of the property module, ultimately resulting in a simplified 3D model with geometric relationships consistent with the example model. Based on these characteristics, straight line segment elements are used when modeling all main members, diagonal members, and auxiliary members in the example.

[0102] To locate the established line segments for subsequent indexing and assigning them cross-sections and directions, a collection of line segments can be created in Abaqus Python, which can be located using the findAt method.

[0103] S32. Tower diaphragm modeling: Since the diaphragm is subordinate to the tower structure, the dimensional parameters of its peripheral square frame are not independent, so it is unnecessary to separately set the dimensional parameters of the diaphragm, and only the position parameter LRef of the diaphragm needs to be specified. The accompanying Figure 5 enumerates five types of diaphragms involved in this program. Taking Type 1 as an example, the implementation idea of the diaphragm modeling function is introduced.

[0104] First, a function for creating the SeptumType1 diaphragm is defined, with the position number and the basic tower frame array passed in as parameters. It can be observed that the diaphragm also has obvious central symmetry. Therefore, we can take the part in the first quadrant, number each node, and calculate the coordinates of each numbered node in turn within the function according to the number and the positions of the corner points of the diaphragm's peripheral frame. During modeling, a simplification process for node positions is performed, that is, nodes are considered to be located at the midpoint of a line segment or at equal division points of multiple segments. As shown in the accompanying Figure 6 , the No. 3 node is considered to be located at the midpoint of the line segment formed by the No. 2 node and the No. 4 node, and the No. 6 node is the same. According to the numbers, this array is called and passed into the WirePolyLine method as a parameter for cyclic modeling to obtain a quarter of the model, and the remaining three quarters only need to undergo coordinate transformation of the array and repeated cyclic modeling. For example, after determining the coordinates of the corner points of the diaphragm's peripheral frame, the local coordinates of the endpoints of the internal cross members are calculated according to the diaphragm type (as Figure 5 shown). Taking Type 1 as an example, the internal intersection points are located at the midpoint of the side length of the peripheral frame and the centroid, and by calculating the midpoint coordinates and centroid coordinates, they are connected in sequence to form a 'meter'-shaped set of internal members.

[0105] It is noted that for the parts of the diaphragm that do not conform to central symmetry, only 7-6''', 6'-7'', 8-0, and 8''-0'' need to be processed separately. For other types of diaphragms, the processing idea is similar: first simplify the modeling to a quarter based on central symmetry, and then process the parts that do not conform to central symmetry. Similarly, a Set should also be created when creating the diaphragm members.

[0106] S33. Inter-panel cross modeling: The parameters passed into the inter-panel modeling function are also the position number parameter and the coordinate array of the corner points of the basic tower frame. Due to the high symmetry of the transmission tower, the inter-panels on the four sides of the transmission tower at the same position are all identical, so the function modeling idea can also be simplified to first establish the inter-panel cross of a certain side, and then perform cyclic modeling based on central symmetry.

[0107] Similar to the diaphragm, the program also designs modeling functions for different tower inter-panels, and the accompanying Figure 7 shows the 6 designed tower inter-panels. The inter-panels are also modeled through the key node numbering method, and a Set is also created when creating the members.

[0108] S34. Tower leg modeling: The basic frame of the tower leg is the three edges of a triangular pyramid, and the size of its bottom triangle (see the accompanying Figure 8 triangle composed of edges 1-2, 1-3, and 2-3 in the figure) depends on the characteristic parameters . The independent dimensional characteristic parameter of the tower leg is its height and the tower leg root spread . According to these parameters, the spatial coordinates of point 0, point 1, point 2, and point 3 can be obtained through simple geometric operations, and the WirePolyLine command is called to connect edge 1, edge 2 and edge 3 to establish the basic frame of the tower leg. Similarly, a Set also needs to be created when building the tower leg members.

[0109] S35. Tower head modeling: According to the accompanying Figure 9 , the tower head of the portal-type tower can be divided into two modules: the tower head body and the crossarm.

[0110] For the tower head body, it can generate the corner point coordinate array of the tower head body according to the dimensional parameters, generate the basic frame of the tower head body by taking the intersection coordinate array of the tower head body as a parameter, and then establish two decorative parts, namely the diaphragm model and the inter-panel cross model, on the basic frame. The code for tower body modeling can be reused in the modeling of the tower head body, and only a new set of dimensional parameters, diaphragm position number parameters and inter-panel cross position number parameters need to be added.

[0111] For the crossarm, the program designs two different crossarm modeling functions, which are respectively for the pentahedral crossarm and the hexahedral crossarm, see the accompanying Figure 10 and the accompanying Figure 11 , the former is used to mount the conductor, and the latter is used to mount the ground wire.

[0112] The characteristic parameters of the layer structure that can be extracted for the pentahedral crossarm are as follows: the width of the edge at the end of the crossarm , the number of crossarm layers , the "height" parameter along the direction of the edge of the lower surface , and the position number parameter LRef. According to summation, the x-coordinates of the two vertices at the tip of the crossarm can be calculated. Based on the symmetry of the crossarm along the x-z plane and the horizontal feature of the lower surface, the calculation formula for the corner points on each edge of the tower body can be borrowed to obtain the main body corner point coordinates of the crossarm. Then, the corner point coordinates are passed in as parameters, and the WirePolyLine method is called to perform cyclic line connection to obtain the four edges of the pentahedral structure. The flow chart of the relevant algorithm is shown in the accompanying Figure 12 , the modeling method of the crossarm inter-panel cross is similar to the modeling method of the tower body inter-panel cross, which will not be further described.

[0113] The characteristic parameters of the layer structure that can be extracted for the hexahedral crossarm are as follows: the width of the upper edge at the end of the crossarm , the width of the lower edge , the end lifting height Number of layers on the upper side of the crossbeam The number of bottom surface layers (m) and parameters along the direction of the top surface edge. The "height" parameter along the direction of the lower side edge. ,like Figure 11 The parameters along the upper lateral edge of the hexahedron shown are respectively , , , The height parameters along the direction of the lower side edge are respectively , , , , The lifting height of the lower side edge of the crossarm The position number parameter is LRef. Similarly, calling the WirePolyLine method to loop through the lines yields the eight edges of the hexahedral structure. For modeling the inter-segment of a hexahedral crossarm, the entire side of the crossarm can be considered as one inter-segment, and the lines can be connected sequentially according to the node numbering method.

[0114] Grounding supports are typically installed on the lower side or end face of the upper crossarm. In this example, the hexahedral crossarm is the upper crossarm, and the grounding support can be considered as its decorative structure. The grounding support structure is relatively simple; it can be considered as a single-section pentahedral crossarm structure with a horizontal lower side and only the lower surface having section crossovers installed. Therefore, the modeling approach for pentahedral crossarms can also be applied to grounding support structures.

[0115] The specific implementation process of mesh generation, element and section attribute assignment, and orientation assignment of the transmission tower line element model described in step S4, combined with instance analysis, is as follows:

[0116] S41. Arrange mesh seeds for the line element model in the global scope, and set the seed spacing parameter SeedSize (0.5m in this embodiment). Abaqus will automatically divide each line segment into multiple small unit segments according to the built-in algorithm to achieve uniform mesh division.

[0117] S42. Define the truss section and beam section respectively: In this example, the cross-sectional area of ​​the truss section is 0.01m². 2 The material properties are defined only by density (7850 kg / m³). 3 The elastic modulus (206 GPa) and yield strength (345 MPa) of the beam are respectively, and the cross-sectional shape of the beam is L160. 14. L140 10. L125 8. L110 10. L90 7. L70 6. L50 4. Material properties are defined only for density (7850 kg / m³). 3 The elastic modulus (206 GPa) and yield strength (345 MPa and 420 MPa) are calculated. Sections are created in batches using a loop script, and the corresponding sections are assigned based on the member's Set by calling the SectionAssignment method. See the attached flowchart for the relevant algorithm. Figure 13 .

[0118] Note: In this embodiment, the "SectionAssignment method" mentioned in step S42 refers to associating and binding a pre-created section attribute object containing material constitutive parameters (such as elastic modulus and Poisson's ratio) and geometric section parameters with the corresponding geometric region of the transmission tower spatial member, so that the geometric region has the physical properties to participate in mechanical calculations. It should be understood that SectionAssignment is only the specific interface name in the Abaqus script environment in this embodiment. In other processing software, similar mapping mechanisms such as attribute assignment or component definition can be used to achieve the same technical effect.

[0119] S43. Based on the component type and mechanical analysis requirements, assign element types to components in different Sets: main members, diagonal members, and crossbeams use three-dimensional beam elements B31, while auxiliary members such as inter-section crossbeams use three-dimensional truss elements T3D2. The element types are specified in batches by traversing the component Sets.

[0120] S44. By inputting a vector that is not parallel to its axis for each beam element, the unique local spatial coordinate system of the beam element is automatically determined through vector cross product operation, thereby determining its spatial orientation.

[0121] For example, for an L-shaped angle steel section, the straight line containing the outer edge of any flange is used as the normal vector of the reference plane. The cross product of this normal vector and the tangent vector of the line element uniquely determines the direction of the driven vector. Furthermore, this establishes the local coordinate system of the beam element section, thereby accurately simulating the orientation of the angle steel in the actual structure. Figure 14 As shown.

[0122] The specific implementation process of verifying and outputting the geometric quality of the transmission tower model in step S5, combined with the example, is as follows:

[0123] S51. Verify the key dimensions of the transmission tower line element model, including tower height, tower leg root opening, crossarm length, and crossarm height, with errors controlled within 0.01m. For nodes where multiple components intersect, use a Python script to traverse the endpoints of all line elements and force the endpoints with coordinate errors within 0.0001m to merge into the same node. See the attached flowchart for the relevant algorithm. Figure 15 .

[0124] S52. Run the modeling script in the Abaqus script interface to obtain the transmission tower line element model for subsequent Abaqus finite element seismic response analysis. The parametric modeling results are attached. Figure 16 As shown.

[0125] The above description is merely a preferred embodiment of the present invention. This embodiment uses a T-shaped straight-line transmission tower as an example to illustrate the method and system of the present invention in detail, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention, such as applying this method to other tower types such as cat-head or goblet-shaped towers, or implementing it based on other finite element software platforms, should be covered within the scope of protection of the present invention.

Claims

1. A rapid modeling method for structural line element transmission towers for disaster inversion, characterized in that, The method includes the following steps: S1. Transmission Tower Structural Feature Decomposition and Parametric Feature Definition: The overall structure of the transmission tower is decomposed into hierarchical features to establish a parametric feature system that includes size feature parameters and location feature parameters. S2. Establishment of global coordinate system and analytical calculation of node coordinates of transmission tower: Based on the global coordinate system, according to the size characteristic parameters defined in step S1, establish the analytical calculation formula of the main material node coordinates, and solve the spatial coordinates of the node in batches through the accumulation of floor height and symmetric mapping. S3. Modular modeling of transmission tower based on straight line segment elements: Based on the spatial coordinates of the nodes obtained in step S2, first establish a core load-bearing frame composed of main materials, then add cross diaphragms and inter-section cross auxiliary materials on the basis of the core load-bearing frame. Utilize the central symmetry, and generate tower legs, tower body and crossarm structure by mirroring the quarter structure through coordinate transformation. Then, give a unique identifier to the generated straight line segment elements to obtain the initial geometric model of transmission tower elements. S4. Mesh generation, element and section attribute assignment, and orientation assignment of the initial transmission tower line element geometric model: Based on the initial transmission tower line element geometric model obtained in step S3, the model is meshed, element types are assigned, section attributes are defined, and the orientation of the angle steel members is calibrated. The orientation calibration includes: for beam element members, based on the tangent vector of the straight line segment element and the reference plane normal vector determined based on any edge line of the angle steel section, the unique local spatial coordinate system of the beam element is automatically determined through vector cross product operation, so as to uniquely determine the spatial orientation of the beam element. Through the above process, it is transformed into a transmission tower finite element model with the ability to perform mechanical analysis for earthquake disaster simulation. S5. Geometric quality verification and output of transmission tower model: Perform geometric simplification and quality check on the finite element model of the transmission tower obtained in step S4, and finally output a geometrically accurate finite element model of the transmission tower that can be directly used for seismic response analysis.

2. The rapid modeling method for structural line element transmission towers oriented towards disaster inversion as described in claim 1, characterized in that: Step S1 specifically includes the following sub-steps: S11. The transmission tower is divided into three major modules: tower body, tower legs, and tower head. The tower body is regarded as a multi-layered regular square truncated pyramid, the tower legs are regarded as four triangular pyramids, and the tower head is further divided into tower head body, crossarm, and ground wire support sub-modules. S12. Define dimensional characteristic parameters: width of the base of the tower. Top layer width Total number of floors in the tower Each floor height Where i is the floor number; the tower leg height Tower leg root opening The dimensional characteristics of the crossarm include: crossarm length, end width, and layer height. S13. Define positional characteristic parameters: module installation layer number, inter-section type number, and transverse diaphragm arrangement position LRef, to determine the position of the substructure in the whole in the form of sequence number.

3. The rapid modeling method for structural line element transmission towers oriented towards disaster inversion according to claim 1, characterized in that: Step S2 includes the following sub-steps: S21. Establish a global coordinate system: the origin O (0,0,0) is the center of the bottom surface of the tower, the Z-axis is vertically upward, and the X and Y axes are horizontally distributed; S22. Calculate the coordinates of the nodes between the tower leg and the main material of the tower body: The coordinates of the i-th node on the edge of the tower leg and the tower body are calculated using the following formula: ； in, x-axis coordinates of the nodes For the y-axis coordinate of the node, The z-axis coordinate of the node For the width of the base of the tower, For the width of the top layer of the tower, The total number of stories in the tower and the height of each story are: , where i is the layer number; k is the current layer number of the tower leg or tower body being calculated; S23. Utilizing central symmetry, the coordinates of all nodes on the other three edges can be directly mapped from the coordinates of the nodes on the first quadrant edge.

4. The rapid modeling method for structural line element transmission towers oriented towards disaster inversion according to claim 1, characterized in that: Step S3 specifically includes the following sub-steps: S31. Modeling the basic framework of the tower body: Traverse the node coordinate array, use the spatial line feature modeling method to connect adjacent layer nodes on the same edge in sequence, generate the main material straight line segment line element, and form the four-sided frustum framework of the tower body. S32. Tower body diaphragm modeling: Take the corresponding layer nodes according to the location number LRef, connect them in sequence to form a square outer frame, and use the central symmetry of the distribution of the internal components of the diaphragm to generate internal rods, thus completing the diaphragm line element modeling. S33. Intersection Cross Modeling: Taking a single side as a reference, first calculate the intersection point of the line elements of the two intersecting diagonal lines, generate the line elements of the intersecting diagonal straight line segments, and then symmetrically generate the intersection structure of the other three sides. S34. Tower Leg Modeling: Based on the bottom nodes of the tower body, model the tower legs according to their height. With the base of the tower leg Generate a triangular pyramid frame, and then arrange inter-segmental intersecting line elements on the three sides respectively; S35. Tower head modeling: Reuse the tower body modeling logic to sequentially build the tower head body, crossarm, and ground wire support. The crossarm is treated as a pentahedron or hexahedron, and line segment elements are generated according to the node coordinates.

5. The rapid modeling method for transmission towers based on structural line elements for disaster inversion as described in claim 1, characterized in that: Step S5 specifically includes the following sub-steps: S51. Geometric quality verification: The key dimensions of the transmission tower line element model are checked, including tower height, tower leg root opening, crossarm length, and crossarm height. The error is controlled within the preset threshold range. For nodes where multiple components intersect, traverse the endpoints of all line elements; S52. Model Output: Output the verified transmission tower line element model as a three-dimensional mechanical model, retaining the line element information and node coordinate data, to provide a basis for subsequent seismic resilience analysis of power grid structure.

6. A rapid modeling system for structural line element transmission towers for disaster inversion, characterized in that, include: The parameterized feature definition module is used to perform hierarchical feature decomposition on the overall structure of the transmission tower and establish a parameterized feature system that includes size feature parameters and location feature parameters. The node coordinate analysis and calculation module is used to establish the coordinate analysis and calculation formula of the main material node based on the global coordinate system and the size feature parameters defined by the parameterized feature definition module. It solves the spatial coordinates of the node in batches through the accumulation of floor height and symmetric mapping. The modular modeling module is used to solve the node spatial coordinates obtained by the node coordinate analytical calculation module. First, a core bearing frame composed of main materials is established. Then, cross diaphragms and inter-section cross auxiliary materials are added on the basis of the core bearing frame. The tower legs, tower body and crossarm structure are generated by mirroring the quarter structure through coordinate transformation using central symmetry. The generated straight line segments are uniquely identified to obtain the initial transmission tower line element geometric model. The attribute assignment and mesh generation module is used to perform mesh generation, element type assignment, section attribute definition and angle steel member orientation calibration based on the initial transmission tower line element geometric model, so as to give it mechanical properties equivalent to the actual model and transform it into a transmission tower finite element model that can be directly used for earthquake disaster simulation. The quality verification and output module is used to perform geometric simplification and quality checks on the finite element model of the transmission tower, ensuring that the line element combination relationship conforms to the actual structural connection, and finally outputting a geometrically accurate final finite element model of the transmission tower that can be directly used for seismic response analysis.

7. The rapid modeling system for structural line element transmission towers for disaster inversion according to claim 6, characterized in that, The parameterized feature definition module is specifically used to: divide the transmission tower into three major modules: tower body, tower leg, and tower head. The tower body is regarded as a multi-layered regular square truncated pyramid, the tower leg is regarded as four triangular pyramids, and the tower head is further divided into tower head body, crossarm, and ground wire support sub-modules. Define dimensional characteristic parameters: width of the base of the tower. Top layer width Total number of floors Each floor height Where i is the floor number; the tower leg height Tower leg root opening The dimensional characteristics of the crossarm include, but are not limited to: crossarm length, end width, and layer height. Define location characteristic parameters: module installation layer number, inter-section type number, and transverse diaphragm arrangement position LRef. The node coordinate analysis and calculation module uses the following formula to calculate the node coordinates: ； in, x-axis coordinates of the nodes For the y-axis coordinate of the node, The z-axis coordinate of the node For the width of the base of the tower, For top layer width, The total number of floors and the height of each floor are... , where i is the layer number; k is the current layer number of the tower leg or tower body being calculated.

8. The rapid modeling system for structural line element transmission towers for disaster inversion according to claim 6, characterized in that, The modular modeling module is specifically used for: tower body diaphragm modeling: taking the corresponding layer nodes according to the location number LRef, connecting them sequentially to form a square outer frame, generating the internal members of the diaphragm according to the central symmetry method, and completing the diaphragm line element modeling; Inter-joint modeling: Taking a single side as a reference, first calculate the intersection point of the line elements of the two intersecting diagonal lines, generate the line elements of the intersecting diagonal straight line segments, and then symmetrically generate the inter-joint structure of the other three sides. Tower leg modeling: Based on the bottom nodes of the tower body, model according to the tower leg height. With the base of the tower leg Generate a triangular pyramid frame, and then arrange inter-segmental intersecting line elements on the three sides respectively; Tower head modeling: Reuse the tower body modeling logic to sequentially build the tower head body, crossarm, and ground wire support. The crossarm is treated as a pentahedron or hexahedron respectively, and line segment elements are generated according to the node coordinates.

9. The rapid modeling system for structural line element transmission towers for disaster inversion according to claim 6, characterized in that, The attribute assignment and mesh generation module is specifically used for: automatically completing mesh generation in general finite element software by arranging mesh seeds on line segment elements and setting seed spacing parameters; defining and assigning component section attributes, and realizing batch creation and assignment of sections through loop scripts; assigning truss elements or beam elements to different types of components according to component analysis requirements; for beam element components, automatically determining the unique local spatial coordinate system of the beam element through vector cross product operation based on the tangent vector of the line segment element and the normal vector of the reference plane, realizing spatial orientation calibration of the beam element, wherein the normal vector of the reference plane is determined according to the straight line on any wing edge edge line of the angle steel section.

10. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed by the processor, they implement the steps of the rapid modeling method for structural element transmission towers oriented towards disaster inversion as described in any one of claims 1 to 5.

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