CAD-based civil engineering three-dimensional concrete and three-dimensional template metering method

Abstract

The invention relates to the technical field of civil engineering construction, and particularly discloses a CAD-based civil engineering three-dimensional concrete volume and template metering method, which comprises the following steps: in a two-dimensional mode, processing each engineering component to obtain an initial two-dimensional model; switching the CAD working space into a three-dimensional mode; extracting geometric parameters of the initial three-dimensional model through a three-dimensional model geometric parameter extraction algorithm to obtain a parameter data set; performing parameter constraint on the parameter data set to obtain parameter data of a logic dependency relationship; classifying and grouping the parameter data of the logic dependency relationship to obtain a logic structure model, and automatically generating a complete three-dimensional model through a built-in three-dimensional function of a CAD (Computer Aided Design) platform; the method supports multi-specialty collision detection and design defect pre-judgment, a CAD kernel is directly used for achieving calculus operation, the space overlapping error of two-dimensional calculation quantity is eliminated, and almost-error-free engineering quantity calculation of the three-dimensional concrete volume and the three-dimensional template area in the off-line environment is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering construction, and in particular relates to a CAD-based measurement method for civil engineering three-dimensional concrete and three-dimensional formwork. Background Art

[0002] Formwork, concrete, and rebar are the three most critical systems in civil engineering, and formwork and concrete are closely interrelated. Traditional formwork and concrete measurement relies primarily on manual calculations based on two-dimensional drawings, which is inefficient, inaccurate, and prone to errors. In the case of special-shaped structures, manual calculations can be extremely inaccurate or even impossible.

[0003] With the development of science and technology in my country, computerization and simulation of three-dimensional models have begun to be used in the field of civil engineering, gradually replacing manual calculations and greatly improving efficiency. However, the following problems still exist:

[0004] High cost of use: Currently, the annual cost of using a set of mainstream concrete and formwork computerization software is no less than 12,000 yuan, which is paid annually and becomes invalid after expiration;

[0005] It is completely dependent on the Internet and cannot be used in areas with poor or no Internet signal.

[0006] The underlying technical architecture and logical relationships of existing commercial computerized software are still based on the outdated two-dimensional planar architecture of decades ago. Although efficiency has been improved, the core of the software inevitably uses nested planar formulas, and the problem of large errors has not been completely solved. It is not applicable to special-shaped structural systems and cannot calculate special-shaped structures, forcing a reversion to manual calculations.

[0007] Although existing commercial software computerized processes can display in three dimensions, this 3D display is only a simulation, not a true 3D model, i.e., "fake 3D", and cannot detect errors or flaws in drawings;

[0008] The computerized results of existing commercial software are still presented in the form of two-dimensional graphics, which are not intuitive and difficult for non-professionals to interpret clearly. At the same time, the output engineering quantities are tabular values, which are extremely easy to be tampered with, and the reliability and authenticity of the data cannot be guaranteed.

[0009] In this regard, the inventors propose a CAD-based measurement method for three-dimensional concrete and three-dimensional formwork in civil engineering to solve the above problems. Summary of the Invention

[0010] The purpose of the present invention is to provide a CAD-based method for measuring three-dimensional concrete and three-dimensional formwork in civil engineering to solve the problems raised in the above-mentioned background technology.

[0011] To achieve the above object, the present invention provides the following technical solutions:

[0012] A method for measuring the volume of concrete in civil engineering based on CAD comprises the following steps:

[0013] In the 2D mode, each engineering component is processed by layer and color, and the initial outline is drawn to obtain the initial 2D model;

[0014] Switch the CAD workspace to 3D mode;

[0015] Extracting geometric parameters of the initial three-dimensional model using a three-dimensional model geometric parameter extraction algorithm to obtain a parameter data set;

[0016] Preliminarily processing the parameter data set to obtain a processed parameter data set, and performing parameter constraints on the processed parameter data set to obtain parameter data with a logical dependency relationship;

[0017] The parameter data of the logical dependency relationship are classified and grouped to obtain a logical structure model, and a complete three-dimensional model is automatically generated through the built-in three-dimensional function of the CAD platform.

[0018] Preferably, the step of obtaining the initial three-dimensional model includes:

[0019] In the two-dimensional environment, a two-dimensional sketch is constructed using two-dimensional graphic elements including a plane profile or a cross section, a profile, etc.;

[0020] Switch the CAD workspace to 3D modeling mode;

[0021] By utilizing the built-in 3D commands of CAD such as stretching, sweeping, lofting, cutting, shelling, interference, and Boolean operations, the 2D template sketch is converted into a 3D model entity to generate a model with 3D information. The model parameter data set includes component volume, template area, perimeter, moment of inertia, gyration radius, and 3D coordinates.

[0022] Preferably, the parameter constraint method is: through a preset rule base, geometric constraints and logical dependencies between parameters in the processed model parameter data set are established to obtain parameter data of the logical dependencies.

[0023] Preferably, the steps for implementing the three-dimensional model geometric parameter extraction algorithm include:

[0024] Utilize the CAD's own functions to divide complex models into several discrete sub-areas;

[0025] Perform high-precision numerical integration on each sub-region to calculate the volume Vi and area Ai;

[0026] Summarize the data of each sub-area to obtain the total concrete volume V of the component;

[0027] The calculation formula of the volume is:

[0028] Vi=∫VidV

[0029] Perform high-precision double numerical integration on each sub-region to calculate the area Ai;

[0030] The area is calculated as follows:

[0031]

[0032] Where Ai is the i-th surface unit generated after meshing the surface of the three-dimensional model;

[0033] Summarize the data of each sub-area to obtain the total concrete area of ​​the component;

[0034] The calculation formula of the total volume V of the concrete is:

[0035] V=ΣVi

[0036] The calculation formula for the total template area A1 of the component is:

[0037] A1=ΣAi。

[0038] Preferably, the process of automatically generating a complete three-dimensional model includes:

[0039] Based on the parameter data of each engineering component, the original model of the corresponding engineering component is obtained by distinguishing by layers and colors through the 3D model geometric parameter extraction algorithm;

[0040] The parameter data of components corresponding to the logical relationship are classified and grouped, and appropriate Boolean operations are performed to automatically deduct the spatial overlap and interference of components to obtain the final components and the overall logical structure model;

[0041] Utilize CAD's own instructions to automatically obtain the three-dimensional concrete engineering quantity; copy the three-dimensional model, release the integrity of the three-dimensional model, adjust the surface area attributes, deduct the invalid surfaces of the top and bottom surfaces corresponding to the three-dimensional model, and after secondary Boolean operations, automatically generate the overall three-dimensional template.

[0042] A CAD-based civil engineering three-dimensional formwork measurement method includes the following steps:

[0043] By calling the corresponding CAD function instructions, the direct engineering quantities such as the 3D volume and template area of ​​the required components can be automatically calculated, and the auxiliary engineering quantities or information such as length and 3D coordinates can be obtained at the same time;

[0044] Through the Boolean operation function of CAD itself, overlapping or interfering areas are automatically deducted and completed automatically using special instructions to obtain concrete engineering quantity data;

[0045] After automatically deducting overlapping or interfering areas, remove useless top and bottom surfaces, and use special instructions to automatically complete the calculation of template engineering quantity data.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] (1) The cost of using the present invention is almost zero, and no renewal is required; no network is required and it can be used in any area; the technical architecture is an advanced three-dimensional technical architecture, which completely eliminates and abandons the old two-dimensional technical architecture; it is not only applicable to ordinary structures but also compatible with special-shaped structures; the true three-dimensional model display can be observed from any angle, and can provide real-time guidance for various processes such as design, cost estimation, construction, and supervision; the measurement data is three-dimensional data, rather than flat two-dimensional data, which is intuitive, easy to understand, and cannot be modified manually, thus ensuring the authenticity and reliability of the data from the source.

[0048] (2) The present invention automatically generates three-dimensional concrete and formwork quantities through the two-dimensional primitive drawing and stretching commands built into CAD, eliminating tedious manual drawing steps; automatically extracts model geometric parameters, greatly improves the efficiency of converting engineering drawings into digital models, shortens the design cycle, and adopts adaptive grid technology for non-standard shapes or curved surface structures, which can segment and integrate local geometric characteristics to meet the requirements of model complexity in different engineering scenarios; thus, it makes it possible to obtain complex three-dimensional templates that are difficult to achieve with traditional two-dimensional planar design, and provides accurate model data for subsequent engineering analysis and construction preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a flow chart of a method for obtaining a 3D civil engineering template based on CAD according to the present invention;

[0050] Figure 2 This is a flow chart of a CAD-based civil engineering concrete volume measurement method of the present invention;

[0051] Figure 3 This is a rendering of a square Roman column in Example 1 of the present invention;

[0052] Figure 4 This is a table showing the calculation data of the concrete and formwork quantities of the square Roman columns in Example 1 of the present invention;

[0053] Figure 5 Schematic diagram of the three-dimensional effect and template area of ​​the square Roman column in Example 1 of the present invention;

[0054] Figure 6This is a two-dimensional initial structure diagram of the hyperbolic circular end bridge pier in the second embodiment of the present invention;

[0055] Figure 7 Schematic diagram of the three-dimensional effect and template area of ​​the hyperbolic round-end bridge pier in Example 2 of the present invention. DETAILED DESCRIPTION

[0056] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0057] Example 1:

[0058] like Figure 1-5 As shown, square Roman columns

[0059] Data acquisition and modeling steps:

[0060] 2D sketch construction:

[0061] Create a new layer "Base" in CAD, set the color to red, and draw the following rectangles to create a 2D sketch;

[0062] Draw rectangle 1: length and width 0.65m × 0.65m;

[0063] Draw rectangle 2: length and width 0.60m × 0.60m;

[0064] Draw rectangle 3: length and width 0.70m × 0.70m;

[0065] Draw rectangle 4: length and width 0.60m × 0.60m;

[0066] Draw rectangle 5: length and width 0.72m × 0.72m;

[0067] Switch the workspace to 3D modeling mode, use the EXTRUDE command to stretch 0.1m along the Z axis to generate a 3D solid model, call the FILLET command multiple times to perform 3D chamfers with different radii; call the Boolean union command (UNION) to merge the above five solid models.

[0068] Create a new layer "Column Body" and set the color to cyan.

[0069] Draw a rectangle of 0.50m x 0.50m to create a 2D sketch of the column.

[0070] Use the EXTRUDE command to stretch 3.4m along the Z axis to generate a 3D solid model;

[0071] Create a new layer "Groove" and set the color to green.

[0072] Use the cylinder command (CYLIEDER) to generate 12 φ60 cylinders, use the sphere command (SPHER) to generate 12 φ60 spheres, overlap the center of the cylinder surface and the center of the sphere, call the Boolean operation union command (UNION) to merge all cylinders and spheres, call the Boolean operation difference command (SUBTRACT) to perform the difference operation between the column body and the cylinder / sphere to form the groove model in the four directions of the column body.

[0073] Create a new layer "Top Seat" and set the color to pink.

[0074] Since the size of the top seat and the base are exactly the same, only the upper and lower positions are opposite, the three-dimensional mirror command (3DMIRROR) is used to mirror and generate the top seat model.

[0075] The Boolean union instruction (UNION) is called to merge the three original models of the base, column body, and top seat to generate the final three-dimensional model.

[0076] Using the special command (MASSPROP), the concrete volume of the square Roman column is 1.22m 3 ;

[0077] Then use the entity release command (EXPLODE), change the surface area properties, delete the top and bottom surfaces of the column, and use the Boolean operation union command (UNION) again to call the area command (AREA), and the overall template engineering volume of the square Roman column is 11.80m 2 ;

[0078] Effect comparison:

[0079] Manual calculation shows that the concrete volume is 1.72m 3 , the template engineering volume is 10.04m 2 In this case, due to the presence of multiple arc chamfers and the integration of cylinders and spheres, the shape approximation algorithm and formula algorithm of trapezoidal surfaces instead of arc surfaces and triangular surfaces instead of arc surfaces were inevitably used in the process. As a result, the manual calculation of the engineering quantities of both concrete and formwork exceeded the allowable value and were judged to be incorrect values.

[0080] The time consumption of the whole process of the present invention is significantly shortened compared with manual calculation, and the error of both the concrete engineering quantity and the formwork engineering quantity is almost zero.

[0081] Example 2: Hyperbolic Circular End Pier

[0082] like Figure 6 and Figure 7As shown, the 2D sketch is constructed:

[0083] Create a new layer "Pier Head" and set the color to red.

[0084] Create a new layer "Pier Body" and set the color to blue.

[0085] Copy the original plan, delete all dimensions, and keep the center line.

[0086] Switch the workspace to 3D mode, use the 3D rotation command (3DROTATE) to convert the main view and left view of the pier from plan to elevation, rotate the left view elevation 90°, and move it to coincide with the center line of the main view, and move the two sections to the corresponding positions of the main view.

[0087] Use the Loft command (LOFT) to loft a curve with a radius of 4651 to form the original 3D model of pier head 1. Use the Loft command again to loft a curve with a radius of 7812 to form the original 3D model of pier head 2. Use the Boolean Intersection command (INTERSECT) to intersect pier heads 1 and 2 to obtain the pier head model.

[0088] Use the stretch command (EXTRUDE) to stretch the section to the specified height to obtain the original model of the pier body. Use the Boolean operation union (UNION) command to merge the column head and the pier body into a whole to obtain the final three-dimensional model.

[0089] Use the SLICE cut command to cut the top of the pier to form a diagonal groove at the top of the pier.

[0090] Using the special command (MASSPROP), the total concrete volume of the pier is 126.41m 3 ;

[0091] Then use the EXPLODE command to change the surface properties and delete the top and bottom surfaces of the pier. Use the UNION command again to call the AREA command to obtain the overall formwork volume of the pier, which is 165.78 square meters.

[0092] Effect comparison:

[0093] Traditional method: Manual calculation can only calculate the concrete and formwork quantities of the pier body, but cannot process and calculate the concrete and formwork quantities of the hyperbolic part of the pier head.

[0094] The three-dimensional model and engineering quantity of the hyperbolic circular-end bridge pier in this example cannot be completed by existing commercial software.

[0095] The present invention: Adaptive grid precise integration, template area automatically deducts interference surface, takes 9 minutes;

[0096] Compatibility: Supports special-shaped structures, avoids manual calculations, and shortens the design cycle.

[0097] As can be seen from the above, the present invention does not require commercial software, saving costs; offline operation is suitable for remote construction sites. The present invention has high three-dimensional solid accuracy: calculus is directly calculated through the CAD kernel to eliminate two-dimensional projection errors;

[0098] Economical: No software purchase cost, offline operation is suitable for no network environment;

[0099] Improved efficiency: The efficiency of modeling complex special-shaped structures is improved, and the error in engineering quantity calculation is <1%.

[0100] Example 3:

[0101] Component type: Hyperbolic paraboloid concrete wall:

[0102] 2D sketch parameters: Section curve equation is z=0.1x 2 -0.05y 2 , projection range x∈[-2,2] m,y∈[-3,3] m

[0103] Data acquisition and modeling steps:

[0104] 2D sketch construction:

[0105] Create a new layer "Curved Wall" and set the color to blue.

[0106] Trace the curved wall to make it a closed section, use spline curves to draw the curved wall path, and generate discrete point clouds based on equations.

[0107] 3D model generation:

[0108] Switch to 3D mode and use the SWEEP command to sweep the closed section along the path direction to generate a curved wall entity.

[0109] Enable adaptive meshing technology, divide the model into 1000 subregions, and calculate the volume by numerical integration:

[0110]

[0111] Template area calculation:

[0112] Copy the model, delete the top surface, bottom surface and the area interfering with the floor (minus an area of ​​2.5m 2 ).

[0113] Perform surface segmentation and calculate the surface development area (taking curvature correction into account):

[0114]

[0115] Effect comparison:

[0116] Traditional method: Manual calculation cannot handle surface integrals, resulting in errors >15%;

[0117] The present invention: Adaptive grid precise integration, template area automatically deducts interference surface;

[0118] Compatibility: Supports special-shaped structures, avoids manual calculations, and shortens the design cycle.

[0119] As can be seen from the above, the present invention has high three-dimensional solid accuracy: calculus is directly calculated through the CAD kernel to eliminate two-dimensional projection errors.

[0120] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A CAD-based method for measuring the volume of concrete in civil engineering, characterized in that: The following steps are involved: In the 2D mode, each engineering component is processed by layer and color, and the initial outline is drawn to obtain the initial 2D model; Switch the CAD workspace to 3D mode; Extracting geometric parameters of the initial three-dimensional model using a three-dimensional model geometric parameter extraction algorithm to obtain a parameter data set; Preliminarily processing the parameter data set to obtain a processed parameter data set, and performing parameter constraints on the processed parameter data set to obtain parameter data with a logical dependency relationship; The parameter data of the logical dependency relationship are classified and grouped to obtain a logical structure model, and a complete three-dimensional model is automatically generated through the built-in three-dimensional function of the CAD platform.

2. A CAD-based civil engineering concrete volume measurement method according to claim 1, characterized in that: The step of obtaining the initial three-dimensional model includes: In the two-dimensional environment, a two-dimensional sketch is constructed using two-dimensional graphic elements including a plane profile or a cross section, a profile, etc.; Switch the CAD workspace to 3D modeling mode; By utilizing the built-in 3D commands of CAD such as stretching, sweeping, lofting, cutting, shelling, interference, and Boolean operations, the 2D template sketch is converted into a 3D model entity to generate a model with 3D information. The model parameter data set includes component volume, template area, perimeter, moment of inertia, gyration radius, and 3D coordinates.

3. The method for measuring the volume of concrete in civil engineering based on CAD according to claim 1, characterized in that: The parameter constraint method is: through a preset rule base, geometric constraints and logical dependency relationships between parameters in the processed model parameter data set are established to obtain parameter data of the logical dependency relationships.

4. The method for measuring the volume of concrete in civil engineering based on CAD according to claim 1, characterized in that: The implementation steps of the three-dimensional model geometric parameter extraction algorithm include: Utilize the CAD's own functions to divide complex models into several discrete sub-areas; Perform high-precision numerical integration on each sub-region to calculate the volume Vi and area Ai; Summarize the data of each sub-area to obtain the total concrete volume V of the component; The calculation formula of the volume is: Vi=∫VidV Perform high-precision double numerical integration on each sub-region to calculate the area Ai; The area is calculated as follows: Where Ai is the i-th surface unit generated after meshing the surface of the three-dimensional model; Summarize the data of each sub-area to obtain the total concrete area of ​​the component; The calculation formula of the total volume V of the concrete is: V=ΣVi The calculation formula for the total template area A1 of the component is: A1=ΣAi。 5. The method for measuring the volume of concrete in civil engineering based on CAD according to claim 1, characterized in that: The process of automatically generating a complete three-dimensional model includes: Based on the parameter data of each engineering component, the original model of the corresponding engineering component is obtained by distinguishing by layers and colors through the 3D model geometric parameter extraction algorithm; The parameter data of components corresponding to the logical relationship are classified and grouped, and appropriate Boolean operations are performed to automatically deduct the spatial overlap and interference of components to obtain the final components and the overall logical structure model; Utilize CAD's own instructions to automatically obtain the three-dimensional concrete engineering quantity; copy the three-dimensional model, release the integrity of the three-dimensional model, adjust the surface area attributes, deduct the invalid surfaces of the top and bottom surfaces corresponding to the three-dimensional model, and after secondary Boolean operations, automatically generate the overall three-dimensional template.

6. A CAD-based civil engineering three-dimensional template measurement method, characterized in that: The following steps are involved: By calling the corresponding CAD function instructions, the direct engineering quantities such as the 3D volume and template area of ​​the required components can be automatically calculated, and the auxiliary engineering quantities or information such as length and 3D coordinates can be obtained at the same time; Through the Boolean operation function of CAD itself, overlapping or interfering areas are automatically deducted and completed automatically using special instructions to obtain concrete engineering quantity data; After automatically deducting overlapping or interfering areas, remove useless top and bottom surfaces, and use special instructions to automatically complete the calculation of template engineering quantity data.

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