Parametric rapid clearance analysis method for complex building space

Abstract

The application discloses a parameterized rapid clearance analysis method for complex building space and belongs to the technical field of building information modeling. In view of the defects of the existing clearance analysis, such as one-sided sampling, discrete coloring and lack of structured statistics, the structural frame positioning line is projected to the clearance base surface for geometric distance calculation to obtain the beam bottom clearance value, which is written into the component attribute, then normalized continuous chromatography mapping is carried out to realize three-dimensional full-amount coloring, clearance labeling is simultaneously carried out on the specified plane, and a structured statistical table is exported, so that the parameterized clearance analysis closed loop is formed. The application improves the comprehensiveness and geometric robustness of clearance calculation, realizes the persistence of clearance data and the continuous color gradient visualization, and provides accurate clearance data benchmark for building space quality control and subsequent design optimization.

Description

Technical Field

[0001] This invention belongs to the field of building information modeling technology, specifically involving a parametric rapid clearance analysis method for complex building spaces, applicable to batch calculation, visualization analysis and statistical output of the clearance at the bottom of frame beams in building structural engineering. Background Technology

[0002] Building Information Modeling (BIM) technology uses various relevant information and data of a building project as a basis to create a three-dimensional model, which also includes the actual information of the building. In the detailed design phase of MEP (Mechanical, Electrical, and Plumbing) pipeline integration, the clear height under the structural beams is a key constraint controlling the routing and arrangement of pipelines. Traditional methods of clear height analysis mainly rely on manual experience: using measurement tools in Revit software to screen areas that may not meet the clear height requirements, then sectioning the model and measuring the distance between the ground and the upper surface in the section view to obtain the clear height of that area; or importing the model into third-party software such as Navisworks, selecting and marking areas with insufficient clear height, and then returning to Revit for adjustments. Both methods require manual experience, are cumbersome, time-consuming, and prone to omissions.

[0003] Chinese invention patent application CN117494274A discloses a method and system for analyzing the net height of a BIM model based on the Dynamo tool. The method first acquires information on all structural frame beams within the BIM model and reads their height parameters. Then, it reads the top elevation parameters of each structural frame beam, subtracts the top elevation parameters from the beam height parameters to obtain the bottom elevation of the structure. Next, it takes a point on the bottom surface of each structural frame beam as the center point of the bottom surface, and emits a ray vertically downwards from this center point, taking the point on the floor slab below where the ray hits as the target point to obtain the floor slab elevation. Then, it subtracts the bottom elevation of the structure from the floor slab elevation to obtain the net height of the beam bottom. Finally, it filters the net height of each beam bottom according to preset height requirements, identifying structural frame beams that meet and do not meet the height requirements, and assigns them colors accordingly. Beams that meet the requirements are uniformly represented in green, while beams that do not meet the requirements are assigned different proportions of red according to the degree of non-compliance. However, this method relies entirely on subtracting elevation parameters and using a single-point ray method to calculate clearance. A ray emitted downwards from a point on the beam's bottom surface only reflects the local clearance at that sampling point, failing to cover the clearance distribution along the entire beam's length. Furthermore, it uses binary filtering based on preset height requirements, classifying beams into only two categories—those meeting the requirements and those not—and assigning them green and red respectively, failing to provide full, continuous color coding for all beams with different clearance heights. Simultaneously, this method does not write clearance values ​​into component attributes; clearance data is only used for immediate filtering and coloring, cannot be persistently saved with the model, and cannot be annotated in the plan view, making it impossible to directly read clearance constraints in the plan view during subsequent MEP (Mechanical, Electrical, and Pipeline) system detailing. In addition, this method lacks structured statistical output methods and cannot export statistical tables containing information such as beam type and clearance values.

[0004] Chinese invention patent application CN116127575A discloses a BIM-based method and system for analyzing the net height of indoor pipework spaces in buildings. This method uses a Dynamo plugin to obtain the beam's positioning lines, takes the two endpoints of these lines, and extends the line segments downwards to intersect with the floor slab or ceiling. Based on the Z-value of the intersection point, the net height of the beam bottom is calculated and stored in the beam bottom net height parameter of the beam component. Then, using a Revit view template filter, the beam component is segmented and pattern-filled according to a preset threshold range. Annotations are then made using Revit's "Annotate All" function, and finally, a DWG format file is exported. However, this method still has the following shortcomings: First, its clearance calculation only samples the downward extension line segments from both ends of the positioning line, failing to cover the clearance distribution along the entire beam length, resulting in sampling blind spots for the middle area of ​​the beam or uneven floor surfaces; Second, its coloring relies on Revit view template filters to perform segmented discrete coloring according to preset threshold intervals, requiring the pre-setting of a large number of threshold intervals and corresponding filters, which is cumbersome and results in step-like color jumps, failing to form a continuous clearance color gradient; Third, its planar annotation uses Revit's native "Annotate All" function, with the annotation position automatically determined by the software, making it impossible to precisely control the center position at the bottom of the beam, which is not convenient for directly reading clearance constraints during subsequent MEP and ductwork integration detailing; Fourth, its final export is a DWG drawing file, which fails to form a structured Excel statistical table containing beam type and clearance value, which is not conducive to data analysis and construction handover. Summary of the Invention

[0005] To address the aforementioned deficiencies in existing technologies, this invention provides a parametric rapid clearance analysis method for complex architectural spaces. Based on a building information modeling platform, the method calculates the beam bottom clearance value by projecting the structural frame positioning line onto the clearance foundation surface and performing geometric distance calculations. The clearance value is then normalized and mapped to achieve full three-dimensional coloring. Simultaneously, annotations are performed on a designated plane and statistical tables are exported, forming a closed loop for parametric clearance analysis.

[0006] Specifically, the method of the present invention includes five interconnected steps: calculating the beam bottom clearance value, writing the clearance value into the component attributes, three-dimensional full-volume coloring, planar clearance annotation, and exporting the clearance statistics table.

[0007] In the beam bottom clearance calculation stage, the structural frame and the clearance foundation surface are extracted. The positioning line of the structural frame is projected onto the clearance foundation surface, and the geometric distance between the positioning line and the clearance foundation surface is calculated. Combined with the beam height parameters of the structural frame, the beam bottom clearance value is obtained. Unlike existing technologies that rely on elevation parameter subtraction, single-point ray method, or two-endpoint line segment extension method, this invention projects the entire positioning line of the structural frame onto the clearance foundation surface, calculates the geometric distance, and then subtracts the beam height to obtain the clearance value. This covers the spatial relationship along the entire beam length direction, does not rely on the completeness of elevation parameters, and can accurately reflect the clearance distribution even for beams with variable cross-sections, inclined beams, or uneven floor surfaces, avoiding blind spots caused by single-point sampling or two-endpoint sampling.

[0008] During the stage of writing the clearance value into the component attributes, the clearance value at the bottom of the beam is formatted as a string and then written into the component attributes of the structural frame. Specifically, the numerical value of the clearance value at the bottom of the beam is converted into a string, invalid digits after the decimal point are removed, and the prefix "beam bottom clearance-" and the suffix "mm" are added to form a formatted clearance string, which is then written into the "annotation" attribute of the structural frame. By writing the clearance value into the component attributes, the clearance data is persistently saved with the model and can be read and called at any subsequent stage, solving the problem of clearance data being lost after one use in the prior art.

[0009] In the 3D full-scale coloring stage, color ranges are set, and the beam bottom clearance values ​​of each structural frame are normalized and mapped to the color ranges. All structural frames in the 3D view are then fully colored. Specifically, an RGB color range is set, and a numerical remapping command is called to normalize all beam bottom clearance values ​​to the preset range. Then, a color range command is called to continuously map the normalized clearance values ​​to the RGB color range, obtaining color values ​​corresponding to each structural frame. These color values ​​are then assigned to all structural frames in the 3D view using a view coloring command. Unlike existing technologies that rely on view template filters for segmented discrete coloring based on preset threshold ranges, this invention uses normalized values ​​and continuous color mapping to make all structural frames present a continuous color gradient according to their clearance size. This eliminates the need to pre-set numerous threshold ranges and filters, allowing for intuitive identification of areas with tight or excess clearance.

[0010] In the planar clearance annotation stage, the beam bottom centerline is extracted and annotation points are located. The clearance values ​​of the beam bottom of each structural frame are annotated in the specified plane. Specifically, the beam height parameter of the structural frame is read and half of the value is taken to obtain the distance that the beam positioning line is offset downwards; the beam positioning line and the vertical direction vector are extracted, and the beam bottom centerline is obtained by offsetting downwards by the half-value distance; the planar annotation point is located at the center position of the beam bottom centerline, the specified plane is selected and the clearance string is formatted, and the clearance annotation is generated at the planar annotation point. Unlike the existing technology that uses software automatic annotation function, this invention uses the midpoint of the beam bottom centerline for precise positioning, so that the clearance annotation is accurately attached to the center position of the beam bottom of each beam, instead of the annotation position being automatically determined by software. This directly serves the subsequent MEP pipeline design and construction, and the pipeline designer can directly read the clearance constraints of the beam bottom in the plan view without repeatedly switching the 3D view or consulting the attribute table.

[0011] In the stage of exporting the clearance statistics table, the component attributes and beam bottom clearance values ​​of the structural frame are read and exported to form a clearance statistics table. Specifically, the formatted clearance string in the "annotation" attribute of the structural frame and the type attribute of the structural frame are read, and the type attribute and clearance value are exported to form a structured statistics table containing beam type and clearance data, which facilitates construction handover and quantity analysis. Unlike the existing technology of exporting DWG drawing files, this invention exports an Excel structured statistics table containing component type attributes and clearance values, which can be directly used for data analysis and material statistics without further drawing conversion.

[0012] The beneficial effects of this invention are as follows: by replacing elevation parameter subtraction and single-point or two-endpoint sampling with overall projection of the positioning line and geometric distance calculation, the comprehensiveness and geometric robustness of the clearance calculation are improved; by writing the clearance value into the component attributes, the model persistence of the clearance data is realized; by replacing segmented threshold discrete coloring with full normalized continuous color gamut mapping, the clearance distribution is presented as an intuitive spatial color gradient, without the need for cumbersome filter presets; by accurately locating and marking the midpoint of the beam bottom centerline on a specified plane, a direct planar reference is provided for the in-depth development of electromechanical and pipeline systems; by exporting a structured Excel clearance statistics table, construction briefing and data analysis are facilitated, thus forming a closed loop of parametric clearance analysis from calculation, visualization to statistical output. Attached Figure Description

[0013] Figure 1 This is a flowchart of the parametric analysis of the present invention, showing the connection between the five steps: beam bottom clearance calculation, attribute writing, three-dimensional coloring, planar annotation, and statistical export.

[0014] Figure 2This is a schematic diagram illustrating the logical method for extracting the structural frame and calculating the beam bottom clearance in Revit, showing the data flow of nodes such as Curve.Project, Geometry.DistanceTo, and Geometry.Translate.

[0015] Figure 3 This is a schematic diagram illustrating the logical method of adding the beam bottom clearance value to the "annotation" attribute, showing the string formatting and the connection relationship of the Element.SetParameterByName node.

[0016] Figure 4 This is a sample of the annotation attributes that have been added in this invention, showing that the "Annotation" field in the structural frame attribute table displays "Beam bottom clear height - ****mm".

[0017] Figure 5 This is a schematic diagram of the logical method of adding different colors to all beams in Revit 3D according to different clearances, showing the data flow of nodes such as Math.RemapRange, Color.Range, and Element.OverrideColorInView.

[0018] Figure 6 This is a schematic diagram of the three-dimensional model of the beam after coloring, showing that the frame beams with different clearance heights present a continuous color spectrum.

[0019] Figure 7 This is a schematic diagram of the logical method of marking the bottom clearance of all beams in a plane according to the present invention, showing the data flow of beam bottom centerline extraction, midpoint positioning and TextNote.ByLocation node.

[0020] Figure 8 This is a schematic diagram of the planar annotation formed by the present invention, showing the clearance values ​​of each frame beam in the plan view.

[0021] Figure 9 This is a schematic diagram of the logical method for extracting beam attributes to form an Excel table of beam bottom clearance statistics according to the present invention, showing the data flow of the Element.GetParameterValueByName and Data.ExportExcel nodes.

[0022] Figure 10 This is the final beam bottom clearance statistics table formed by the present invention, which shows a structured table containing structural frame types and corresponding clearance values. Detailed Implementation

[0023] The invention will be described in detail below using a commercial complex project as an example. The project's structural system is a frame structure, containing multiple structural frame beams with different cross-sectional dimensions. A batch analysis of the bottom clearance of all frame beams is required to guide subsequent detailed design of the electromechanical pipeline system.

[0024] I. Calculation of the net clearance at the bottom of the beam Dynamo is used to read the structural frame and the foundation slab for net clearance calculation in Revit, defining the calculation direction as vertically downwards. The positioning lines of the structural frame are extracted, and the Curve.Project command is used to project these lines onto the net clearance foundation surface, obtaining the projected positioning line geometry. The Geometry.DistanceTo command is used to calculate the geometric distance between the projected positioning line and the net clearance foundation surface. Simultaneously, the Element.GetParameterValueByName command is used to read the beam height parameters of the structural frame, and the Geometry.Translate command is used to offset the beam positioning lines vertically. Combining the geometric distance and beam height parameters, the net clearance value at the bottom of the beam is calculated. This process, based on the overall projection of the positioning lines and the geometric distance calculation, covers the spatial relationship along the entire beam length, does not rely on the completeness of elevation parameters, and accurately reflects the net clearance distribution even for beams with variable cross-sections, inclined beams, or uneven floor surfaces, avoiding blind spots caused by single-point sampling or sampling at two endpoints.

[0025] II. Write the clearance value into the component properties The beam bottom clearance value obtained in step one is converted into a string using the `String from Object` command, and the `String.Replace` command is used to remove invalid digits after the decimal point. The prefix "beam bottom clearance-" and the suffix "mm" are added using Code Block, and this is combined with the clearance string formed in step one using `List.Map` to create a formatted clearance string. Finally, the `Element.SetParameterByName` command is used to write the formatted clearance string into the "Comment" attribute of all structural frames, ensuring the clearance data is persistently saved with the model.

[0026] III. 3D Full Shading The `Color.ByARGB` command is used to set the RGB color range and define the start and end colors of the color spectrum. The `Math.RemapRange` command is then used to normalize all beam bottom clearance values, redistributing them between 0 and 1. The `Color.Range` command is used to connect the beam bottom clearance values, the RGB color range, and the normalized index, allowing for continuous color assignment to different beam bottom clearance values ​​without the need for pre-setting numerous threshold ranges and filters. Finally, the `Element.OverrideColorInView` command is used to connect all structural frames and their corresponding color values, performing color replacement and shading in the 3D view to present a continuous color spectrum for all frame beams according to their clearance size.

[0027] IV. Plane Clearance Marking The `Element.GetParameterValueByName` command is used to extract the beam height parameter of the structural frame, and then divided by 2 to obtain the distance the beam positioning line needs to be offset downwards. The beam positioning line and the vertical downward vector are extracted, and the `Geometry.Translate` command is used to offset it downwards by half the beam height distance to obtain the beam bottom centerline. The `Curve.PointAtParameter` command is used to locate the plane annotation point at the center of the beam bottom centerline, instead of letting the software automatically determine the annotation position. Then, the `TextNote.ByLocation` command is used to select the plane to be annotated, the format string for the beam bottom clearance value, the plane annotation position, and the text alignment, generating the clearance annotation in the plane. Finally, the `String.Replace` and `TextNote.SetText` commands are used to remove trailing zeros from the annotation string, resulting in a concise plane clearance annotation.

[0028] V. Exporting the Net Air Statistical Table The `Element.GetParameterValueByName` command is used to read the formatted net height string "beam bottom clearance - ****mm" from the structural frame's "Annotation" properties. Simultaneously, the `Element.GetParameterValueByName` command is used to read the structural frame's type properties, and other built-in Revit property values ​​can also be read. Then, the `Data.ExportExcel` command is called, setting the file path, table name, starting row and column, and the beam property values ​​to be displayed in the table. The type properties and net height values ​​are then exported, automatically generating a statistical table of beam bottom clearances. This table can be directly used for data analysis and material statistics without further drawing conversion.

[0029] Through the above process, the net clearance values ​​of all structural frame beams in the project were calculated in batches, attributed, 3D colored, plane labeled, and statistically exported in a short period of time. The generated 3D color model intuitively presents the net clearance distribution gradient, the plane label provides a direct reference for the detailed design of the electromechanical and pipeline system, and the statistical table facilitates construction handover and data analysis.

[0030] Taking a typical high-rise office floor as an example, this floor has a building area of ​​approximately 2,500 square meters, with a frame column grid spacing of 8 to 12 meters and approximately 120 structural frame beams. Existing technologies can automatically calculate the net height and filter colors, but can only output binary two-color results indicating whether the requirements are met or not, or rely on view template filters for segmented discrete coloring, and cannot generate planar annotations or structured statistical tables. During subsequent MEP (Mechanical, Electrical, and Pipeline) integration detailing, designers still need to manually check the net height of each beam and record the data, taking approximately 2 to 3 hours in total. However, using the method of this invention, a single parametric run can complete the net height calculation, attribute writing, 3D full coloring, planar annotation, and Excel statistical table export for all approximately 120 beams, taking approximately 10 to 15 minutes. Furthermore, the generated planar annotations and statistical tables can be directly used for MEP integration detailing and construction handover, without requiring secondary manual processing.

[0031] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A parametric rapid clearance analysis method for complex architectural spaces, characterized in that, Based on the building information modeling platform, the net clearance value of the beam bottom is obtained by projecting the positioning line of the structural frame onto the net foundation surface and calculating the geometric distance. The net clearance value is then normalized and mapped to achieve three-dimensional full coloring. Simultaneously, it is labeled on a specified plane and a statistical table is exported to form a parametric net clearance analysis closed loop. The method includes the following steps: S1. Calculation of beam bottom clearance value: Extract the structural frame and the clear foundation surface, project the positioning line of the structural frame onto the clear foundation surface, calculate the geometric distance between the positioning line and the clear foundation surface, and combine the beam height parameters of the structural frame to obtain the beam bottom clearance value. S2. Write the clearance value to the component properties: After formatting the clearance value at the bottom of the beam as a string, write it into the component properties of the structural frame. S3, Three-dimensional full coloring: Set a color range, normalize the beam bottom clearance value of each structural frame and map it to the color range, and perform full coloring on all structural frames in the three-dimensional view. S4. Plane clearance annotation: Extract the center line of the beam bottom and locate the annotation point, and annotate the beam bottom clearance value of each structural frame in the specified plane; S5. Exporting the Clearance Statistics Table: Read the component properties and beam bottom clearance values ​​of the structural frame, and export them to form a clearance statistics table.

2. The parameterized rapid airspace analysis method according to claim 1, characterized in that, In S1, the step of projecting the structural frame positioning line onto the clear foundation surface and calculating the geometric distance includes: The parametric design tool is used to extract the structural frame and the floor slab below as the clear foundation surface, and the positioning line of the structural frame is extracted. The curve projection command is used to project the positioning line onto the clear foundation surface, and the geometric distance command is used to calculate the distance between the projected positioning line and the clear foundation surface. The geometric translation command is used to offset the positioning line in the vertical direction to the beam height, and the beam bottom clearance value is obtained by combining the geometric distance.

3. The parameterized rapid airspace analysis method according to claim 1, characterized in that, In S2, the string formatting of the beam bottom clearance value includes: Convert the numerical value of the beam bottom clearance to a string, remove invalid digits after the decimal point, add the prefix "beam bottom clearance-" and the suffix "mm" to form a formatted clearance string.

4. The parameterized rapid airspace analysis method according to claim 1 or 3, characterized in that, In S2, the component attributes written into the structural frame include: Invoke the parameter setting command to write the formatted blank string into the "Comment" attribute of the structural frame.

5. The parameterized rapid airspace analysis method according to claim 1, characterized in that, In S3, the setting of color ranges and the normalization of the beam bottom clearance value include: Set the RGB color range, call the numerical remapping command to normalize all beam bottom clearance values ​​to the preset range, call the color range command to map the normalized clearance values ​​to the RGB color range, and obtain color values ​​corresponding to each structural frame; call the view shading command to assign the color values ​​to all structural frames in the 3D view.

6. The parameterized rapid airspace analysis method according to claim 1, characterized in that, In S4, the step of extracting the center line of the beam bottom and locating the marking point includes: Read the beam height parameters of the structural frame and take half of the value to obtain the distance by which the beam positioning line is offset downwards; extract the beam positioning line and the vertical direction vector, and call the geometric translation command to offset downwards by the half-value distance to obtain the center line of the beam bottom; call the curve point acquisition command to locate the plane marking point at the center position of the center line of the beam bottom.

7. The parameterized rapid airspace analysis method according to claim 1 or 6, characterized in that, In S4, marking the net clearance value at the bottom of the beams of each structural frame in the specified plane includes: Select the format string for the specified plane and beam bottom clearance values, call the plane text annotation command to generate clearance annotations at the plane annotation points; remove trailing zeros from the string of the clearance annotations.

8. The parameterized rapid airspace analysis method according to claim 1, characterized in that, In S5, the step of reading and exporting the component attributes and beam bottom clearance values ​​of the structural frame includes: The parameter reading command is invoked to read the formatted blank string in the "comment" attribute of the structural framework, as well as the type attribute of the structural framework; the export file path, table name, and starting row and column are set, and the data export command is invoked to export the type attribute and the formatted blank string to form a blank statistics table.

9. The parameterized rapid airspace analysis method according to claim 1, characterized in that, The method is applicable to the structural clearance analysis and clearance statistics of structural framework systems of the same form, and has parameterized reusability.

10. The parameterized rapid airspace analysis method according to claim 1, characterized in that, The building information modeling platform is Revit / Dynamo.

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