A culvert design method based on a refined BIM model

Abstract

This application relates to the field of culvert design technology, specifically to a culvert design method based on a refined BIM model. The method includes: establishing a culvert BIM model; converting the model into a culvert finite element model; meshing the model to obtain all mesh elements for each component in the culvert finite element model; calculating the first evaluation value, local curvature, second evaluation value, and evaluation coefficient for each mesh element; filtering all mesh elements to obtain the mesh to be refined; refining the mesh; optimizing the culvert BIM model through seismic simulation analysis of the refined culvert finite element model; and generating culvert design drawings using the optimized culvert BIM model. This application avoids unnecessary global refinement, reduces computational resource consumption, and simultaneously achieves refined analysis to improve the accuracy of culvert structural mechanical performance evaluation, ensuring the safety and reliability of culvert design.

Description

Technical Field

[0001] This application relates to the field of culvert design technology, specifically to a culvert design method based on a refined BIM model. Background Technology

[0002] Culverts, as an important infrastructure, are widely used in roads, railways, water conservancy, and other fields. The design and construction of culverts require consideration of various factors, including geological conditions, load effects, and seismic performance. BIM technology and finite element analysis technology have brought unprecedented visualization and information capabilities to the design of complex structures such as culverts. BIM technology provides parametric 3D models with rich attribute information, while finite element analysis can accurately simulate and evaluate the mechanical performance of the structure. Combining these two technologies enables digital management of the culvert design process, thereby helping to optimize culvert structural performance, reduce design errors and loopholes, and ensure its safety and reliability under various complex conditions.

[0003] To improve the accuracy of evaluating the mechanical performance of culvert structures, refined analysis is required. However, existing methods, after converting BIM models into finite element models, are not suitable for refined analysis. To achieve refined analysis, small-size meshes are usually used to divide the converted finite element models. However, small-size meshes lead to a significant increase in the number of meshes in the refined finite element models, resulting in a large consumption of computational resources during finite element analysis and seriously affecting the design efficiency of culverts. Summary of the Invention

[0004] To address the aforementioned technical issues, a culvert design method based on a refined BIM model is provided to resolve existing problems.

[0005] The solution to the technical problem presented in this application is to provide a culvert design method based on a refined BIM model, comprising the following steps:

[0006] Based on the structural information of the culvert, a BIM model of the culvert is established, which is then converted into a finite element model of the culvert. The model is then meshed to obtain all the mesh elements of each component on the finite element model of the culvert.

[0007] Analyze the number of adjacencies between each grid cell and different components, evaluate the situation where the grid cell is located at the splice between different components, and calculate the first evaluation value of each grid cell;

[0008] The local curvature of each grid cell is calculated based on the curvature of the local region where each grid cell is located; and the difference between the local curvature of each grid cell and the grid cells of the component to which it belongs is analyzed to calculate the second evaluation value of each grid cell.

[0009] Based on the first and second evaluation values, the evaluation coefficient of each grid unit is determined, and all grid units are screened to obtain the grids to be refined. All grids to be refined on the culvert finite element model are refined, and seismic simulation analysis is performed on the refined culvert finite element model to optimize the culvert BIM model. Finally, the optimized culvert BIM model is used to generate culvert design drawings.

[0010] Preferably, the structural information of the culvert includes at least the geometric parameters of all components of the culvert, the material type of the culvert, and the load requirements of the culvert.

[0011] Preferably, the calculation of the first evaluation value for each grid cell includes:

[0012] Analyze the number of times each vertex corresponding to each mesh cell appears on all component surfaces;

[0013] The first evaluation value is the fusion result of the number of times all vertices corresponding to each mesh cell are evaluated.

[0014] Preferably, the analysis of the number of times each vertex corresponding to each mesh cell appears on all component surfaces includes:

[0015] Number all vertices of all mesh elements on the finite element model of the culvert, and form a mesh vertex set by the sequence numbers of all vertices of all mesh elements distributed on each component.

[0016] Count the number of times the corresponding vertex number of each grid cell appears in all grid vertex sets.

[0017] Preferably, the calculation of the local curvature of each mesh cell includes:

[0018] All grid cells directly connected to each grid cell are denoted as neighboring grid cells;

[0019] Obtain the normal vectors of the plane containing each grid cell and the planes containing each neighboring grid cell;

[0020] Calculate the sine of the angle between the normal vector of the plane containing each grid cell and the normal vectors of the planes containing its neighboring grid cells;

[0021] The local curvature is the result of fusing the sine values ​​between each mesh cell and all its neighboring mesh cells.

[0022] Preferably, the specific process of the fusion is as follows: calculate the mean of the sine values ​​between each grid cell and all its neighboring grid cells, and use it as the local curvature of each grid cell.

[0023] Preferably, the calculation process for the second evaluation value is as follows: calculate the average value of the local curvature of all grid cells corresponding to the component to which each grid cell belongs; and take the difference between the local curvature of each grid cell and the average value as the second evaluation value of each grid cell.

[0024] Preferably, the evaluation coefficient is the sum of the normalized first evaluation value and the normalized second evaluation value.

[0025] Preferably, the process of obtaining the mesh to be refined is as follows: obtain the segmentation threshold of the evaluation coefficients of all mesh elements on the culvert finite element model, and select all mesh elements whose evaluation coefficients are greater than the segmentation threshold as the mesh to be refined.

[0026] Preferably, the refinement process for all meshes to be refined on the culvert finite element model includes: using a mesh refinement algorithm to refine all meshes to be refined on the culvert finite element model to obtain a refined culvert finite element model.

[0027] This application has at least the following beneficial effects:

[0028] This application analyzes the adjacency of each mesh element with different components and calculates a first evaluation value for each mesh element. The advantage of this approach is that it considers the situation where the mesh element belongs to the splicing or boundary between different components, thus identifying mesh elements located in weak points at component boundaries. This allows for mesh refinement, enabling accurate assessment of stress concentration distribution in weak mesh elements during subsequent mechanical evaluation of the culvert's finite element model. This facilitates local optimization of weak points during the design phase, improving the overall structural performance. Secondly, it calculates the local curvature of each mesh element. This is beneficial because it considers the non-coplanarity between each mesh element and its adjacent mesh elements, reflecting the curvature of the local area where the mesh element is located and assessing the unevenness and complex geometry of that area. Finally, it calculates a second evaluation value for each mesh element. This is beneficial because it considers the differences in curvature characteristics between each mesh element and the remaining mesh elements of its component, identifying mesh elements located at geometrically discontinuous locations such as holes, grooves, and shoulders, thus allowing for mesh refinement and subsequent evaluation of those mesh elements. The stress concentration distribution in the area is analyzed, and local optimization is performed during the design phase to improve the crack resistance and overall performance of the structure. The evaluation coefficients for each mesh element are determined, and all mesh elements are screened to obtain the meshes to be refined. Refining all the meshes to be refined on the culvert finite element model has the advantage of avoiding unnecessary global refinement by selecting mesh elements in weak and geometrically discontinuous areas, reducing computational resource consumption, and more accurately capturing stress concentration and deformation, thus more accurately assessing the mechanical performance of the structure. Seismic simulation analysis is performed on the refined culvert finite element model to optimize the culvert BIM model, and culvert design drawings are generated using the optimized culvert BIM model. The advantage of seismic simulation analysis is that it identifies areas in the culvert BIM model that need further optimization, thereby improving the accuracy of the mechanical performance assessment of the culvert structure through refined analysis, reducing computational resources for finite element analysis, improving culvert design efficiency, reducing design errors and loopholes, and ensuring the safety and reliability of the culvert design. Attached Figure Description

[0029] The following section provides a more detailed description of a culvert design method based on a refined BIM model, in conjunction with the accompanying drawings.

[0030] Figure 1 A flowchart illustrating the steps of a culvert design method based on a refined BIM model, provided for embodiments of this application;

[0031] Figure 2 A flowchart illustrating the steps of the method for obtaining the refined culvert finite element model provided in this application embodiment. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of a culvert design method based on a refined BIM model, in conjunction with the accompanying drawings and implementation examples, is provided. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0034] Please see Figure 1 The diagram illustrates a flowchart of a culvert design method based on a refined BIM model, according to an embodiment of this application. The method includes the following steps:

[0035] Step 1: Based on the structural information of the culvert, establish a BIM model of the culvert, convert the model into a finite element model of the culvert, and mesh it to obtain all the mesh elements of each component on the finite element model of the culvert.

[0036] Building Information Modeling (BIM) provides a multi-dimensional information model that supports the entire lifecycle of a building project. Furthermore, it has great potential in optimizing culvert design, improving construction efficiency, reducing costs, and enhancing safety management.

[0037] Culverts are generally composed of multiple components. Based on the structural information of the culvert, a BIM model of the culvert is constructed using BIM software.

[0038] It should be noted that, for example, the multiple components of a culvert include the wing walls, end walls, and cutoff walls at the culvert opening, and the culvert abutments, cover plates, and approach slabs at the culvert body. Secondly, the structural information of the culvert includes the names of all components of the culvert, geometric parameter information, load requirements of the culvert, and material type of the culvert, such as the material type of concrete, brick, stone, steel reinforcement, etc.

[0039] In this embodiment, the culvert BIM model is constructed using Revit software. The use of Revit software is a well-known technology and will not be described in detail here. As other implementation methods, implementers can use software such as Tekla, BIM5D, and Bentley to construct the culvert BIM model.

[0040] The BIM model of the culvert was converted into a finite element model using finite element conversion software.

[0041] In this embodiment, the FEMTransfer software is used to convert the culvert BIM model into a finite element model. The use of FEMTransfer software is a well-known technology. As another implementation method, the implementer can use the ypermesh software for model conversion.

[0042] The finite element model of the culvert is then meshed to obtain all the mesh elements corresponding to each component on the finite element model of the culvert.

[0043] In this embodiment, the finite element model is coarsely meshed in ABAQUS software. The mesh type is tetrahedral and the size is 300mm. As for other implementation methods, the implementer can set it according to the actual situation.

[0044] It should be noted that each face of the tetrahedron is a triangle, therefore, each grid cell is a triangle with three vertices.

[0045] At this point, all the mesh elements corresponding to each component on the culvert finite element model are obtained.

[0046] Step 2: Analyze the number of adjacent components of each grid cell, evaluate the situation where the grid cell is located at the splice between different components, and calculate the first evaluation value of each grid cell.

[0047] When performing seismic analysis on a culvert finite element model, the joints between different components are generally the weak points of the culvert structure. For example, the junction between the main arch and the protective arch, and the junction between the wing wall and the cutoff wall, are most prone to cracking during an earthquake. Therefore, in order to better simulate the stress distribution at the joints of components in the culvert, it is necessary to perform more refined meshing at the joints to more accurately capture changes in stress distribution, thereby optimizing the culvert BIM model and improving the crack resistance and overall stability of the culvert structure.

[0048] Based on the above analysis, the more different components a single grid cell connects, the more likely that grid cell is to be a weak point in the culvert, and the more prone it is to multi-directional cracking, crushing, or slippage during an earthquake. Therefore, by analyzing the components adjacent to each grid cell, the first evaluation value is calculated as follows:

[0049] Number all vertices of all mesh elements on the finite element model of the culvert, and form a mesh vertex set by the sequence numbers of all vertices of all mesh elements distributed on each component.

[0050] The number of times the index of each vertex corresponding to each grid cell appears in all grid vertex sets;

[0051] Calculate the average of the number of times each vertex corresponds to each grid cell, and use it as the first evaluation value for each grid cell;

[0052] It should be noted that each component corresponds to a set of mesh vertices. The larger the number, the more components the vertex belongs to, that is, it is shared by multiple components, reflecting that the vertex is more likely to be located at the splicing part of different components. The larger the first evaluation value, the more culvert components are adjacent to the surface area where the mesh unit is located, reflecting that the mesh unit is more located at the junction of multiple components, belongs to the weak part of the culvert, and its structure is more complex, requiring subsequent fine processing.

[0053] At this point, the first evaluation value for each grid cell is obtained.

[0054] Step 3: Calculate the local curvature of each grid cell by considering the curvature of the local area where each grid cell is located; and analyze the difference in local curvature between each grid cell and the other grid cells of its component to calculate the second evaluation value of each grid cell.

[0055] Furthermore, for the remaining mesh elements located at non-boundary points within the culvert, when the surface area of ​​this mesh element is situated at geometrically discontinuous locations such as holes, grooves, or shoulders within the structural members, the abrupt changes in the cross-sectional dimensions or shape of the members cause uneven stress distribution during seismic analysis. This leads to stress concentration, which in turn reduces the strength of the structural members, making them more susceptible to deformation, cracking, and fracture during earthquakes. Therefore, to more accurately analyze areas within the culvert prone to stress concentration, it is necessary to perform more refined meshing on the surface areas of geometrically discontinuous locations such as holes, grooves, and shoulders within the structural members, thereby optimizing the culvert BIM model.

[0056] Secondly, at geometrically discontinuous parts, due to local abrupt changes in the cross-sectional shape or topology of the component, the surface area will exhibit sharp bends, such as depressions, protrusions, or corners. This results in a relatively large degree of local bending in these surface areas. In the finite element model of a culvert, since the mesh elements are generally triangular or quadrilateral, they represent a plane and cannot reflect the local bending characteristics of the real culvert surface.

[0057] All grid cells directly connected to each grid cell are denoted as neighboring grid cells;

[0058] Obtain the normal vectors of the plane containing each grid cell and the planes containing each neighboring grid cell;

[0059] It should be noted that obtaining the normal vector of a plane is a well-known technique and will not be elaborated upon here.

[0060] Calculate the sine of the angle between the normal vector of the plane containing each grid cell and the normal vectors of the planes containing its neighboring grid cells;

[0061] Calculate the mean of the sine values ​​between each grid cell and all its neighboring grid cells, and use this as the local curvature of each grid cell;

[0062] It should be noted that the calculation of the angle between the normal vectors of the two planes is a well-known technique and will not be elaborated here. Secondly, the larger the sine value, the closer the planes of the two grid cells are to being perpendicular. The larger the local curvature, the greater the degree of local curvature between the grid cell and its neighboring grid cells. This reflects that the surface area where the grid cell is located is more curved locally, the more drastic and uneven the surface changes are, the higher the degree of geometric discontinuity, and the more complex the geometric shape changes.

[0063] Furthermore, based on the differences in local curvature between each mesh element and the other different mesh elements corresponding to its constituent components, a second evaluation value is calculated, specifically as follows:

[0064] Calculate the average local curvature of all mesh elements corresponding to the component to which each mesh element belongs;

[0065] The difference between the local curvature of each grid cell and the average value is used as the second evaluation value for each grid cell;

[0066] In this embodiment, the mean of the differences between the local curvature of each grid cell and the average value is used as the second evaluation value of each grid cell.

[0067] It should be noted that the larger the second evaluation value, the more significant the difference between the local geometry of the area where the grid cell is located and the average curvature of the component. This indicates that the area where the grid cell is located is more likely to have abrupt surface bending and be a geometric discontinuity, and is more prone to stress concentration. Therefore, the area where the grid cell is located should be further refined into a finer grid.

[0068] At this point, the second evaluation value for each grid cell is obtained.

[0069] Step 4: Based on the first and second evaluation values, determine the evaluation coefficient of each grid unit, filter all grid units to obtain the grid to be refined; refine all the grids to be refined on the culvert finite element model, perform seismic simulation analysis on the refined culvert finite element model, optimize the culvert BIM model, and generate culvert design drawings using the optimized culvert BIM model.

[0070] Furthermore, based on the first evaluation value and the second evaluation value, an evaluation coefficient is determined, specifically as follows:

[0071] The sum of the normalized first evaluation value and the normalized second evaluation value is used as the evaluation coefficient for each grid cell.

[0072] In this embodiment, the first and second evaluation values ​​of all grid cells are normalized using the maximum-minimum normalization method. The maximum-minimum normalization method is a well-known technique and will not be described in detail here. As other implementation methods, implementers may use other methods of the prior art, such as the Z-score normalization method. This embodiment does not impose any special restrictions on this.

[0073] It should be noted that the larger the evaluation coefficient, the more detailed the mesh division of the grid cell needs to be, so as to better simulate the splicing parts of the components in the culvert and the geometric discontinuities such as holes, grooves, and shoulders in the components. This is to evaluate the stress distribution in the seismic analysis of these parts that are prone to stress concentration, and thus optimize the culvert BIM model more accurately.

[0074] Obtain the segmentation threshold for the evaluation coefficients of all mesh elements on the finite element model of the culvert;

[0075] In this embodiment, the Otsu threshold segmentation algorithm is used to obtain the segmentation threshold. The Otsu threshold segmentation algorithm is a well-known technology and will not be described in detail here. As other implementation methods, implementers may use other methods of the prior art, such as cross-validation. This embodiment does not impose any special restrictions on this.

[0076] All grid cells whose evaluation coefficient is greater than the segmentation threshold are selected and denoted as the grid to be refined;

[0077] A mesh refinement algorithm is used to refine all the meshes to be refined on the culvert finite element model to obtain the refined culvert finite element model.

[0078] In this embodiment, an adaptive mesh refinement method is used for mesh refinement. The adaptive mesh refinement method is a well-known technology and will not be described in detail here. As other implementation methods, implementers can use other methods of the prior art, such as mesh refinement methods based on geometric features, mesh refinement methods based on error estimation, etc. This embodiment does not impose any special restrictions on this.

[0079] Furthermore, the flowchart of the method for obtaining the refined culvert finite element model provided in this application embodiment is as follows: Figure 2 As shown.

[0080] The ABAQUS software was used to perform seismic steady-state analysis on the refined culvert finite element model, and the culvert BIM model was optimized. The optimized culvert BIM model was then used to generate culvert design drawings.

[0081] It should be noted that response spectrum analysis of the culvert finite element model was performed using ABAQUS software to evaluate the structural response of the culvert finite element model under seismic loading. By applying seismic loads to the culvert finite element model and performing seismic simulation, stress and displacement contour maps were obtained. Areas in the stress contour map where the stress exceeds the allowable value of the material were identified, which are the weak points in seismic resistance and need to be optimized and reinforced. It was also determined whether the maximum displacement in the displacement contour map met the code limit. Supports were added to areas where the displacement exceeded the code limit to improve the rigidity of the structure, thereby optimizing the culvert BIM model. The optimized culvert BIM model was then used to generate design drawings corresponding to the plan, elevation, and section views.

[0082] For example, if the stress of the main component exceeds the standard, the cross-sectional dimension parameters in the culvert finite element model are increased, such as increasing the thickness of the culvert abutment. If there is stress concentration at a local geometric abrupt change, its geometry is optimized, such as changing the right-angle chamfer at the stress concentration point to a rounded chamfer in the culvert finite element model. If the stress at the connection part is complex, the steel reinforcement is carried out in the culvert finite element model, such as increasing the diameter of the steel bars or reducing the spacing. If the stiffness of the structure is insufficient, auxiliary components such as reinforcing ribs are added at the corresponding positions in the culvert finite element model.

[0083] It should be noted that the response spectrum analysis and the optimization of the culvert BIM model in seismic steady-state analysis are well-known techniques and will not be elaborated here.

[0084] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0085] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0086] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application, without departing from the content of the technical solution of this application, shall fall within the protection scope of the technical solution of this application.

Claims

1. A culvert design method based on a refined BIM model, characterized by, The method includes the following steps: Based on the structural information of the culvert, a BIM model of the culvert is established, which is then converted into a finite element model of the culvert. The model is then meshed to obtain all the mesh elements of each component on the finite element model of the culvert. Analyze the number of adjacencies between each grid cell and different components, evaluate the situation where the grid cell is located at the splice between different components, and calculate the first evaluation value of each grid cell; The local curvature of each grid cell is calculated based on the curvature of the local region where each grid cell is located; and the difference between the local curvature of each grid cell and the grid cells of the component to which it belongs is analyzed to calculate the second evaluation value of each grid cell. Based on the first and second evaluation values, the evaluation coefficient of each grid unit is determined, all grid units are screened to obtain the grid to be refined; all grids to be refined on the culvert finite element model are refined, seismic simulation analysis is performed on the refined culvert finite element model, the culvert BIM model is optimized, and culvert design drawings are generated using the optimized culvert BIM model. The calculation of the first evaluation value for each grid cell includes: Analyze the number of times each vertex corresponding to each mesh cell appears on all component surfaces; The first evaluation value is the fusion result of the number of times said for all vertices corresponding to each mesh cell; The calculation process for the second evaluation value is as follows: calculate the average local curvature of all grid cells corresponding to the component to which each grid cell belongs; and take the difference between the local curvature of each grid cell and the average value as the second evaluation value of each grid cell. The evaluation coefficient is the sum of the normalized first evaluation value and the normalized second evaluation value; The process of obtaining the mesh to be refined is as follows: obtain the segmentation threshold of the evaluation coefficients of all mesh elements on the culvert finite element model, select all mesh elements whose evaluation coefficients are greater than the segmentation threshold, and record them as the mesh to be refined.

2. The culvert design method based on a refined BIM model of claim 1, wherein, The structural information of the culvert includes at least the geometric parameters of all components of the culvert, the material type of the culvert, and the load requirements of the culvert.

3. The culvert design method based on a refined BIM model of claim 1, wherein, The analysis of the number of times each vertex corresponding to each mesh cell appears on all component surfaces includes: Number all vertices of all mesh elements on the finite element model of the culvert, and form a mesh vertex set by the sequence numbers of all vertices of all mesh elements distributed on each component. Count the number of times the corresponding index of each vertex in each grid cell appears in all grid vertex sets.

4. The culvert design method based on a refined BIM model of claim 1, wherein, The calculation of the local curvature of each mesh cell includes: All grid cells directly connected to each grid cell are denoted as neighboring grid cells; Obtain the normal vectors of the plane containing each grid cell and the planes containing each neighboring grid cell; Calculate the sine of the angle between the normal vector of the plane containing each grid cell and the normal vectors of the planes containing its neighboring grid cells; The local curvature is the result of fusing the sine values ​​between each mesh cell and all its neighboring mesh cells.

5. The culvert design method based on a refined BIM model of claim 4, wherein, The specific process of the fusion is as follows: calculate the mean of the sine values ​​between each grid cell and all its neighboring grid cells, and use it as the local curvature of each grid cell.

6. The culvert design method based on a refined BIM model as described in claim 1, characterized in that, The refinement process for all meshes to be refined on the culvert finite element model includes: using a mesh refinement algorithm to refine all meshes to be refined on the culvert finite element model to obtain a refined culvert finite element model.

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