Building construction quality control method

Abstract

The invention discloses a building construction quality control method, and relates to the technical field of building engineering, and the method comprises the steps: building a BIM model; setting an observation station, and performing three-dimensional laser scanning on the constructed building part on the site according to the observation station to obtain a plurality of scanning images; splicing the plurality of scanning images based on the reference point to obtain a three-dimensional point cloud model; selecting a common reference point, moving the BIM model and the three-dimensional point cloud model to the common reference point to enable the two models to coincide, and checking and comparing deviations existing in key point positions on model components; calculating a variance according to the deviation, and determining whether to re-customize the curtain wall plate or not according to the variance; and 3, on the basis of the three-dimensional point cloud model obtained in the step 3, determining whether to re-establish the model according to the variance. According to the method, the real object is converted into the model through field scanning, the model and the BIM model are subjected to superposition comparative analysis, the deviation between the model and the BIM model is rapidly and accurately measured, and BIM model parameters and special-shaped curtain wall plate customization parameters are conveniently corrected in time.

Description

Technical Field

[0001] The invention relates to the technical field of building engineering, and in particular to a building construction quality control method. Background Art

[0002] In the conventional special-shaped curtain wall construction process, the steel structure keel external curtain wall method is usually adopted. The errors in the main building structure construction, steel structure keel production, installation and special-shaped curtain wall panel production process will cause the keel and the special-shaped curtain wall panel installation position to deviate, and the cost of later correction is high, and the aesthetics and integrity of the shape will be affected after correction. Using conventional measurement tools to measure the precise position of all installation nodes of the special-shaped structure is labor-intensive and prone to errors, which directly affects the subsequent construction and overall construction quality. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a construction quality control method.

[0004] The present invention is achieved through the following technical solutions.

[0005] A construction quality control method comprises the following steps:

[0006] Step 1: Establish BIM model;

[0007] Step 2: Set up a measuring station, and perform 3D laser scanning on the completed building parts on site according to the measuring station to obtain multiple scanned images;

[0008] Step 3: stitch multiple scanned images based on the reference points to obtain a 3D point cloud model;

[0009] Step 4: Select a common reference point, move the BIM model and the 3D point cloud model to the common reference point to make the two models overlap, and check the deviations of key points on the model components;

[0010] Step 5: Calculate the variance based on the deviation, and determine whether to re-customize the curtain wall panel based on the size of the variance;

[0011] Step 6: Based on the 3D point cloud model obtained in step 3, determine whether to rebuild the model according to the size of the variance.

[0012] Furthermore, in step 2, a 3D laser scanner is used to perform 3D laser scanning on the completed building parts on site.

[0013] Furthermore, in step three, the error of stitching point cloud is <5mm.

[0014] Furthermore, in step 3, when multiple scanned images are stitched together based on the reference points, a preliminary 3D point cloud image is first formed, and then redundant point cloud models are deleted to obtain the final 3D point cloud model. Redundant point cloud models include vehicles next to the building, construction fences, construction machinery, etc.

[0015] Furthermore, in step four, common reference points include: beam-column nodes at edge positions, measurement reference points, code scanning target points, and the origin of the measurement coordinate system.

[0016] Furthermore, in step five, if the variance is greater than 20 mm, the curtain wall panels are re-customized.

[0017] Furthermore, in step six, for components with variance greater than 20 mm, the model is rebuilt.

[0018] The beneficial effects of the present invention are:

[0019] 1. This method can be applied to large-scale buildings and structures with complex shapes and structures, especially when the installation needs to be completed within the specified construction period but there is a lack of accurate dimensional data support, to avoid material waste and time delay.

[0020] 2. The three-dimensional point cloud model obtained by scanning the entity by this method has high accuracy and strong reliability. The system distance measurement error is ≤2mm, and the error is negligible compared with the overall modeling.

[0021] 3. This method converts the physical object into a model by scanning it on site, and compares and analyzes the overlap with the BIM model, so as to quickly and accurately measure the deviation between the two, so as to facilitate the timely correction of BIM model parameters and special-shaped curtain wall panel customization parameters.

[0022] 4. This method has obvious application advantages in scanning operation areas in unrestricted and restricted environmental areas such as construction sites with large personnel flow, urban streets, etc. It has no obstacles in measurement, small footprint, short construction time, simple and fast operation, no special technical requirements for the person measuring, and high work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a flow chart of a construction quality control method of the present invention;

[0024] Figure 2 Partial cut of the BIM model Figure 1 ;

[0025] Figure 3 Partial cut of the BIM model Figure 2 ;

[0026] Figure 4 Schematic diagram for leveling the instrument;

[0027] Figure 5This is a schematic diagram of the distribution principle of measuring stations;

[0028] Figure 6 To preview the image during scanning;

[0029] Figure 7 The point cloud image after stitching;

[0030] Figure 8 The three-dimensional point cloud model after point cloud cleaning;

[0031] Fig. 9 It is a three-dimensional point cloud model diagram;

[0032] Fig.10 To measure the dimension drawing of the component;

[0033] Fig.11 This is a comparison chart between the 3D point cloud model and the BIM model;

[0034] Fig.12 is the measurement error value diagram;

[0035] Fig.13 This is the reverse modeling diagram. DETAILED DESCRIPTION

[0036] The following further describes the structures involved in the present invention or the technical terms used in these descriptions. These descriptions are only used as examples to illustrate how the methods of the present invention are implemented, and cannot constitute any limitation to the present invention.

[0037] like Figure 1 As shown, taking a certain project as an example, the building shape is a streamlined surface, and the construction quality control method includes the following steps:

[0038] 1. Build a BIM model

[0039] Create a BIM model based on the building's design parameters, see Figure 2-3 .

[0040] 2. 3D laser scanner leveling

[0041] The building of this project is large and complex in shape. Based on the survey results, the 3D laser scanner operator set up a carbon steel tripod, placed the instrument on the carbon steel tripod steadily, fixed the instrument, and adjusted the support legs to make the top surface of the tripod roughly flat. By adjusting the three foot screws at the bottom of the instrument, the original bubble is roughly centered in the leveler. Turn on the leveling function of the instrument leveler for precise leveling, check the electronic bubble displayed on the screen, rotate the foot screws while observing the position of the electronic bubble, and adjust it to the center, and set it as the reference point for point cloud image stitching, see Figure 4 .

[0042] 3. Set parameters and scan the object

[0043] First, according to the actual situation and needs, select the appropriate scanning accuracy. The higher the accuracy, the smaller the point spacing, see Table 1. This project uses three levels of scanning accuracy. Secondly, confirm that the color point cloud function is turned on to collect the actual color of the scanned object to facilitate later point cloud data analysis and processing; turn on the fixed exposure mode to balance the intensity of light during the scanning process; unless there are special circumstances, the atmospheric correction value remains unchanged by default.

[0044] Use the 3D laser scanner correctly to perform scanning operations according to the operating specifications (instrument manual), and perform horizontal scanning in a clockwise direction according to the set parameters. The first round is a warm-up scan, and the instrument automatically circles around. The second round begins the formal scanning. This project uses the third-level scanning accuracy, with a point spacing of 5.7mm@30m. The scanning time for each measuring station is about 15 minutes. In principle, each time a measuring station is changed, it is necessary to ensure that there are three or more common surfaces within the scanning range. See Figure 5 , and after each scan, you can preview the scanned image in the instrument window. Figure 6 .

[0045] Table 1

[0046] Gear Scanning time required for each gear (minutes) Point spacing Preview 2min 15.1mm@10m Level 1 3min 22.6mm@30m Level2 5min 11.3mm@30m Level3 19min 5.7mm@30m

[0047] 4. Data splicing and cleaning

[0048] See also Figure 7-9 After the data collected in the field is copied and decompressed, Trimble Realworks is used to take the first survey station as the horizontal reference point, identify other reference points through the software, and perform image stitching. The stitching point cloud error is <5mm; a preliminary three-dimensional point cloud image is formed.

[0049] In the editing module of the software, select the point cloud model, select the segmentation command, adjust to the appropriate viewing angle, select the required point cloud image, and delete the redundant point cloud models, such as vehicles next to the building, construction fences, construction machinery, etc. Repeat this work to finally obtain the required 3D point cloud model of the main building.

[0050] 5. Generate model and match mold

[0051] After obtaining the required 3D point cloud model, generate the plan, elevation, section and construction image in the software according to the actual site requirements, and mark the relevant component size, angle, elevation and other information on the drawing. Fig.10 .

[0052] Then import the 3D point cloud model into the Revit software, and manually identify the reference points with strong characteristics, such as: beam-column nodes at the edge, measurement reference points, code scanning target points, measurement coordinate system origin, etc. This project uses the beam-column nodes at the edge to perform manual point-to-point movement operations, and gradually move the BIM model and the 3D point cloud model to the common reference points so that the common reference points completely overlap. By looking at the deviation between the comparison models from different angles, such as front view, top view, and side view, manually find the parts with large deviations between the 3D point cloud model and the BIM model, and use measurement tools to measure and annotate, see Figure 11-12 .

[0053] 6. Generate model and match mold

[0054] Regarding the size of the error range, if the deviation range between the key points on the BIM model and the 3D point cloud model components is ≤5 mm, it is within the design error range and can be ignored; when the deviation is greater than 5 mm, the stability of the structure should be verified in a timely manner.

[0055] If the variance of the deviation is greater than 20mm, it will affect the installation of the curtain wall panels and the curtain wall panels will need to be re-customized.

[0056] If the deviations of the key points on the component are x1, x2, x3…x n , the mean is M,

[0057] The variance formula is:

[0058]

[0059] 7. Inverse Parametric Modeling

[0060] Convert the 3D point cloud model file into .rcp format file and import it into Rhino parametric modeling software. Based on the 3D point cloud model of the steel structure keel obtained by actual on-site scanning, for the parts where the variance of the construction deviation value is greater than 20㎜ and may affect the appearance and construction of the curtain wall, establish models of aluminum plates, curtain wall structures, etc., obtain the affected curtain wall size and location information, make detailed annotations, and issue relevant drawings and 3D models to ensure the smooth progress of the subsequent curtain wall installation project. See Fig.13 .

[0061] 8. Contact the manufacturer and correct the components

[0062] Communicate with component manufacturers and deliver the drawings, models, data and other materials generated in the previous steps so that manufacturers can adjust the customized size and installation information of curtain wall panels in a timely manner. Manufacturers will produce and review the curtain wall panels actually constructed on site based on the updated drawings, models, data and other materials to reduce material waste and rework.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction quality control method, characterized in that: The following steps are involved: Step 1: Establish BIM model; Step 2: Set up a measuring station, and perform 3D laser scanning on the completed building parts on site according to the measuring station to obtain multiple scanned images; Step 3: stitch multiple scanned images based on the reference points to obtain a 3D point cloud model; Step 4: Select a common reference point, move the BIM model and the 3D point cloud model to the common reference point to make the two models overlap, and check the deviations of key points on the model components; Step 5: Calculate the variance based on the deviation, and determine whether to re-customize the curtain wall panel based on the size of the variance; Step 6: Based on the 3D point cloud model obtained in step 3, determine whether to rebuild the model according to the size of the variance.

2. The construction quality control method according to claim 1, characterized in that: In step 2, a 3D laser scanner is used to perform 3D laser scanning on the completed building parts on site.

3. The construction quality control method according to claim 1, characterized in that: In step 3, the stitching point cloud error is <5mm.

4. The construction quality control method according to claim 1, characterized in that: In step three, when multiple scanned images are stitched together based on reference points, a preliminary three-dimensional point cloud image is first formed, and then redundant point cloud models are deleted to obtain a final three-dimensional point cloud model.

5. The construction quality control method according to claim 4 is characterized in that: Redundant point cloud models include vehicles next to buildings, construction fences, and construction machinery.

6. The construction quality control method according to claim 1, characterized in that: In step 4, the common reference point is one of the beam-column node at the edge position, the measurement reference point, the code scanning target point, and the origin of the measurement coordinate system.

7. The construction quality control method according to claim 1, characterized in that: In step 5, if the variance is greater than 20 mm, re-customize the curtain wall panels.

8. The construction quality control method according to claim 1, characterized in that: In step six, for components with variance greater than 20 mm, the model is rebuilt.

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