Construction method for column post-injection of subway cover structure based on scanning technology and BIM cooperation

Abstract

This invention discloses a method for rebar installation in subway overpass structures based on scanning technology and BIM collaboration, belonging to the field of building construction technology. The method includes: cleaning the site and marking construction control lines; laying a graduated reference plate to establish precise coordinate references; using a 3D scanner to acquire real point cloud data of existing beam and slab reinforcement; constructing BIM models of the point cloud data and design drawings respectively and precisely aligning their coordinates; parametrically arranging the rebar installation in the fused model and performing collision checks to optimize the rebar model; finally, outputting construction guidance documents to guide precise on-site operations. By scanning to understand the actual distribution of existing reinforcement and using BIM technology for pre-construction simulation and optimization of the rebar installation path, the method fundamentally avoids damage to the existing reinforcement structure during rebar installation, improving the efficiency and safety of rebar installation construction.

Description

Technical Field

[0001] This invention relates to the field of subway overpass construction technology, and in particular to a method for constructing rebar anchoring for subway overpass structural columns based on scanning technology and BIM collaboration. Background Technology

[0002] With the rapid development of urban underground rail transit, the number of buildings above subway stations is also gradually increasing. These buildings can make full use of the space above the subway, thereby improving the utilization rate of urban land.

[0003] The structural columns above subway buildings are key load-bearing components in subway development projects. They primarily support the loads of the superstructure, such as residential and commercial facilities, and transfer these loads to the underground structure or foundation. The existing buildings below, used for subway functions, need to be completed in the first phase of construction. Generally, certain connecting components are reserved for subsequent construction of the superstructure. However, since a considerable amount of time is required after the subway superstructure construction is completed before the superstructure can be built, for continued subway superstructure projects, considering the special safety requirements of subway projects, the design often involves large diameter and numerous reinforcing bars in the beams, and there are deviations in the original beam reinforcement. If construction is carried out entirely according to the original reserved reinforcement positions, it may not only compromise the safety of the superstructure but also damage the existing reinforcement in the subway structure, weakening the load-bearing capacity of the beams and slabs, and thus posing a potential threat to the stability of the subway operation below. Summary of the Invention

[0004] The purpose of this invention is to provide a method for rebar installation in subway overpass structures based on scanning technology and BIM collaboration. By scanning, the actual distribution of existing rebars can be understood, and BIM technology can be used to simulate and optimize the rebar installation path before construction, thereby fundamentally avoiding damage to the existing rebar structure during rebar installation and improving the efficiency and safety of rebar installation.

[0005] To solve the above-mentioned technical problems, the embodiments of the present invention provide a technical solution as follows: A construction method for rebar installation of subway overpass structural columns based on scanning technology and BIM collaboration, comprising the following steps: Step S1: Construction preparation and benchmark establishment: Clean the construction area around the overpass structural column to be rebar installed, and mark the construction control lines around the overpass structural column; lay a scaled benchmark plate within the range determined by the construction control lines, and adjust the position of the benchmark plate so that its edge is aligned with the construction control lines to establish a coordinate benchmark for subsequent scanning and modeling; Step S2: Existing structure 3D information acquisition: Using a 3D scanning device, with the benchmark plate as a coordinate reference, scan the existing beam and slab reinforcement around the overpass structural column, acquire and generate a point cloud data model containing the actual arrangement information of the reinforcement; Step S3: BIM model construction and collaboration: Import the point cloud data model into BIM modeling software to construct a 3D BIM model of the existing structure; at the same time, import the design drawings of the continued column into the BIM model. The information is imported into the same BIM modeling software to generate a design BIM model of the continued column; the design BIM model is precisely matched with the existing structure's 3D BIM model through unified alignment using a coordinate system; Step S4: Parametric arrangement and collision detection of rebar: In the BIM modeling software, according to the design requirements, the rebar model to be installed is parametrically arranged in the corresponding connection area between the existing structure's 3D BIM model and the design BIM model; after the arrangement is completed, the collision detection function of the BIM modeling software is activated to perform collision detection between the rebar to be installed in the rebar model and the existing rebar in the existing structure's 3D BIM model, and the rebar model to be installed is optimized based on the collision detection results; Step S5: Construction information output and on-site implementation: Based on the optimized and adjusted rebar model to be installed, a construction guidance document containing rebar location coordinates, specifications, rebar depth, and arrangement information is output; on-site construction personnel perform drilling and rebar installation operations according to the construction guidance document.

[0006] Furthermore, in step S1, the construction control line is an edge line extending outward 450-550mm from the edge line of the cover structure column; the reference plate is an acrylic plate with millimeter graduations.

[0007] Furthermore, in step S1, when adjusting the reference plate to align its edge with the construction control line, the alignment deviation is controlled to be no greater than 1mm.

[0008] Furthermore, in step S1, before laying the reference plate, the building surface layer within the construction control line area is chiseled down to the structural floor slab elevation to fully expose the actual arrangement of the existing beam and slab reinforcement.

[0009] Furthermore, in step S2, during the scanning process, after each area of ​​a preset width is scanned, the process is paused and the quality of the real-time generated point cloud data is checked. The scanning can only continue after confirming that the outline of the steel bars is clear and there is no missing data.

[0010] Furthermore, in step S3, the positioning reference for the coordinate system alignment includes: the design center position of the structural column on the cover, the scale origin set on the reference plate, and the boundary of the construction control line; after alignment, the coordinate deviation between models is no greater than 1mm.

[0011] Furthermore, in step S4, the parameterized arrangement of the rebar model to be planted includes defining the diameter, implantation depth, exposed length, row spacing, and column spacing of the rebar.

[0012] Furthermore, step S4 also includes: if the collision detection finds that the implantation depth of the rebar to be installed cannot meet the design requirements due to the obstruction of the existing structure, then record the design required depth and the actual implantable depth at that location; perform bearing capacity verification based on the rebar model to be installed, and design a rebar installation node that expands the original column pier form accordingly to meet the structural bearing capacity requirements.

[0013] Furthermore, step S5 also includes: during the rebar installation process, measuring the actual rebar installation parameters and comparing them with the corresponding theoretical values ​​in the rebar model to be installed, calculating the coordinate error, dimensional error, and depth error; recording the error data in the database for data support for model accuracy control and optimization in subsequent similar constructions.

[0014] Furthermore, in step S5, the output construction guidance document includes a plan view of the rebar anchoring points based on the coordinate system of the reference plate, a three-dimensional visualization view, a detailed sectional view, and a bill of quantities.

[0015] The rebar installation method for subway overpass structures based on scanning technology and BIM collaboration provided by this invention, compared with existing technologies, establishes coordinate references using a benchmark plate, accurately grasps the actual distribution of existing structural rebar through 3D scanning, and simulates the rebar installation construction using BIM technology. Based on the simulation results, the rebar installation path is optimized, fundamentally avoiding damage to the existing rebar structure during rebar installation. This greatly ensures the safety of the existing subway overpass structure and the safety of the rebar installation construction. Simultaneously, through a digital process of "scan first, then simulate, then construct," the hidden rebar engineering becomes visible, allowing for the foresight and resolution of all potential conflicts before construction. This makes complex construction intuitive and controllable, significantly reducing on-site trial and error, rework, and adjustment time, and significantly improving construction efficiency. In particular, the recording and storage of error data provides valuable experience for similar projects, providing data support for the model accuracy control and optimization of subsequent similar constructions. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise stated, the figures in the drawings do not constitute a limitation on scale.

[0017] Figure 1 This is a flowchart illustrating the construction steps of a subway overpass structural column rebar installation method based on scanning technology and BIM collaboration in an embodiment of the present invention. Figure 2 This is a schematic diagram of the distribution of reinforcing steel bars in an existing structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of scanning and positioning in an embodiment of the present invention; Figure 4 This is a schematic longitudinal section of the rebar joint of the enlarged column pier in an embodiment of the present invention; Figure 5 This is a schematic cross-sectional view of the rebar joint of the enlarged column pier in an embodiment of the present invention.

[0018] Explanation of reference numerals in the attached drawings: 10, structural column; 20, beam and slab; 21, beam and slab reinforcement; 30, continued column; 301, connection area; 302, rebar joint; 31, column pier; 32, rebar; 40, reference plate; 50, 3D scanning equipment. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the various embodiments of this invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the various embodiments of this invention to facilitate a better understanding of this application. However, the technical solutions claimed in the claims of this application can be implemented even without these technical details and with various variations and modifications based on the following embodiments.

[0020] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0021] The technologies involved in this application include, but are not limited to: BIM (Building Information Modeling), which is a digital three-dimensional model of building information.

[0022] like Figure 1-5As shown, one embodiment of the present invention relates to a method for constructing rebar anchoring for subway overpass structures based on scanning technology and BIM collaboration, comprising the following steps: S1: Construction Preparation and Benchmark Establishment: Clean the construction area around the structural column 10 to be reinforced with rebar, and mark the construction control lines around the structural column 10. Lay a scaled reference plate 40 within the range defined by the construction control lines, and adjust the position of the reference plate 40 so that its edge is aligned with the construction control lines to establish a coordinate benchmark for subsequent scanning and modeling. In one example, the construction control line is a line extending outward from the edge of the structural column 10 by 450-550mm, creating an operating environment for subsequent scanning and rebar 32 construction. This range covers the key stress area of ​​the continued column 30 and also reserves operating space for the installation of scanning equipment and rebar positioning, facilitating the accurate delineation of the scanning boundary. The reference plate 40 is an acrylic plate with millimeter scales, measuring 1000×1000×2mm. Before laying the reference plate 40, chisel away the building surface layer to the structural floor slab elevation within the range of the construction control lines to fully expose the actual arrangement of the existing beam and slab rebar 21. Preferably, the control line is the edge line extending 500mm outward from the column edge. The reference plate 40 needs to be laid flat and stable. When adjusting the reference plate 40 to align its edge with the construction control line, the alignment deviation should not exceed 1mm. A right-angle ruler and a tape measure can be used to assist in the measurement to ensure that the acrylic plate is parallel to the construction control line in both the X-axis and Y-axis directions.

[0023] S2: Existing Structure 3D Information Acquisition: Using a 3D scanning device 50, with the reference plate 40 as the coordinate reference, the existing beam and slab reinforcement 21 around the capped structural column 10 is scanned, and a point cloud data model containing the actual arrangement information of the reinforcement is acquired and generated. In one example, a 3D laser scanner is set up, and with the scale and control lines of the reference plate 40 as the spatial reference system, the area around the column is scanned along the construction control lines. The arrangement of the beam and slab reinforcement 21 and the structural dimensions are associated with the coordinate reference of the reference plate 40, generating a point cloud data model containing complete information on the reinforcement around the capped structural column 10. Preferably, during the scanning process, the area to be scanned is divided into multiple scanning zones. After scanning a strip area of ​​approximately 100mm width, the scanning is paused and the real-time point cloud data is checked. That is, the point cloud quality is previewed through software to ensure that the reinforcement outline is clear and there are no missing or blurry data before continuing, and finally a complete point cloud model is generated. If an abnormality is found, the parameters are adjusted in time and the area is re-scanned.

[0024] Step S3: BIM Model Construction and Collaboration: Import the point cloud data model into BIM modeling software to construct a 3D BIM model of the existing structure, ensuring that the dimensions of the 3D BIM model are consistent with the features of the point cloud data. Simultaneously, import the design drawings of the continued construction column 30 into the same BIM modeling software to generate a design BIM model of the continued construction column 30. Through coordinate system alignment, precisely match the spatial positions of the design BIM model and the existing structure's 3D BIM model, merging the two models into a single collaborative overall model. The core positioning benchmarks for coordinate system alignment include: the design center position of the covered structural column 10, the scale origin set on the benchmark plate 40, and the boundary of the construction control line. After alignment, the coordinate deviation between the models is no greater than 1mm. In one example, the BIM modeling software is Revit. Import the point cloud data into Revit software to create a 3D BIM model of the existing structure, including existing beams, slabs, and reinforcement. Simultaneously, the design drawings for the continued construction column 30 are created as a separate BIM model. These drawings include structural construction drawings, reinforcement layout drawings, and detailed drawings of rebar joint 302. Using the origin of the base plate 40, the control line boundary, and the center of the capping structural column 10 as common reference points, the software's coordinate alignment function is used to precisely merge the two models into a single collaborative master model. The BIM modeling software used in this invention is not limited to Revit; other existing BIM modeling software can also be employed.

[0025] S4: Parametric Layout and Collision Detection of Rebar 32: In the BIM modeling software, according to design requirements, the rebar model to be installed is parametrically arranged within the connection area 301 corresponding to the existing structure's 3D BIM model and the design BIM model. After the arrangement is completed, the collision detection function of the BIM modeling software is activated to perform collision detection between the arranged rebar model to be installed and the existing rebar in the existing structure's 3D BIM model. The rebar model to be installed is optimized based on the collision detection results. In one example, in the collaborative overall model, based on the detailed drawing of the rebar node 302, the rebar model to be installed is generated in the connection area 301 between the existing structure and the continued column 30 using the parametric function. The diameter of the rebar 32 is defined, such as Φ28 or Φ32, the implantation depth (which must meet the design requirement of ≥20d, where d is the diameter of the rebar 32), the exposed length, and the row and column spacing. During the layout process, the rebar 32 is arranged in real time based on the rebar position in the existing structure's 3D BIM model, prioritizing areas with larger existing rebar spacing to initially avoid potential conflicts. The BIM software's clash detection function is then used to check whether the newly installed rebar 32 overlaps with the existing beam and slab rebar 21, and whether there are any obstructions from other rebars within the installation depth range of the rebar 32. The software automatically marks the locations where the rebar to be installed conflicts with the existing rebar. Based on this, the designers adjust the planar position or elevation of the rebar 32 to avoid conflicts and optimize the model of the rebar to be installed. If, due to structural thickness limitations, the adjusted area still cannot meet the design anchorage depth, the design requirement depth and the actual implantable depth at that location are recorded.

[0026] Step S5: Construction Information Output and On-site Implementation: Based on the optimized and adjusted rebar model, output a construction guidance document containing the location coordinates, specifications, depth, and layout information of the rebar 32. On-site construction personnel perform drilling and rebar 32 installation according to the construction guidance document. In one example, the finalized, conflict-free rebar model that meets the stress requirements is output as a lightweight construction drawing, such as a 2D CAD drawing. The drawing must clearly indicate the X and Y axis coordinates of each rebar hole in the reference plate 40 coordinate system, the rebar specifications, the designed rebar 32 depth and layout, and construction precautions; and generate a 3D visualization view, detailed cross-section, and bill of quantities to provide a digital basis for on-site construction handover and quality acceptance. Preferably, during the rebar 32 installation process, the actual rebar 32 parameters are measured and compared with the corresponding theoretical values ​​in the rebar model to calculate the coordinate error, dimensional error, and depth error; the error data is recorded in the database to provide data support for model accuracy control and optimization in subsequent similar constructions. In one example, during construction, it is necessary to record the actual rebar installation parameters and compare them with the model values ​​of the rebar to be installed, forming an error record table and a database to provide empirical data for the accuracy control and optimization of the subsequent column model. The theoretical values ​​of the model are compared with the actual values ​​on site one by one, and the error values ​​of each parameter are calculated. The error record table includes: coordinate errors in the X, Y, and Z axis directions, dimensional errors, such as the diameter deviation and spacing deviation of the newly installed rebar, and depth errors, such as the deviation between the model value of the newly installed rebar insertion depth and the depth of the space that can be inserted on site.

[0027] One embodiment involves a method for constructing rebar anchoring in subway overpass structures based on scanning technology and BIM collaboration. The method further includes: if collision detection reveals that the anchoring depth of the rebar cannot meet design requirements due to obstruction by existing structures, recording the required design depth and the actual implantable depth at that location; performing load-bearing capacity calculations based on the rebar model, and designing a rebar anchoring node 302 that enlarges the original column pier 31 to meet structural load-bearing requirements. For the recorded location, an enlarged column pier 31 area is created in the rebar model, establishing a new rebar anchoring node 302 to compensate for insufficient anchoring depth by increasing the load-bearing area. In one example, considering the location of insufficient rebar depth, the design depth requirements of rebar 32, the actual implantable depth and deviation value, and the design specifications, the mechanical analysis plugin in the BIM software is used to perform a local bearing capacity verification of the node area. The bearing capacity defect of the original design column pier 31 of the continued column 30 under the condition of insufficient rebar depth is verified. A new rebar node 302 is established by expanding the column pier 31 of the continued column 30 to make up for the insufficient rebar depth defect, so as to meet the bearing capacity design requirements of the continued column 30 and ensure that its safety factor meets the design specifications.

[0028] The rebar installation method for subway overpass structures based on scanning technology and BIM collaboration provided by this invention utilizes a reference plate to establish coordinates and accurately grasps the actual distribution of existing steel reinforcement through 3D scanning. It then uses BIM technology to simulate the rebar installation process and optimizes the installation path based on the simulation results. This fundamentally avoids damage to the existing steel reinforcement structure during rebar installation, greatly ensuring the safety of both the subway overpass structure and the rebar installation construction. Furthermore, the digital workflow of "scan first, then simulate, then construct" makes the hidden steel reinforcement work visible, allowing for the foresight and resolution of all potential conflicts before construction. This makes complex construction intuitive and controllable, significantly reducing on-site trial and error, rework, and adjustment time, and significantly improving construction efficiency. In particular, the recording and storage of error data provides valuable experience for similar projects and data support for the model accuracy control and optimization of subsequent similar construction projects.

[0029] 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 and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be defined by the claims.

Claims

1. A method for constructing rebar anchoring for subway overpass structures based on scanning technology and BIM collaboration, characterized in that, Includes the following steps: Step S1: Construction preparation and benchmark establishment: Clean up the construction area around the structural column (10) to be reinforced and mark the construction control lines around the structural column (10); lay a scaled benchmark plate (40) within the range determined by the construction control lines, and adjust the position of the benchmark plate (40) so that its edge is aligned with the construction control lines to establish the coordinate benchmark for subsequent scanning and modeling. Step S2: Existing structure three-dimensional information acquisition: Using a three-dimensional scanning device (50), with the reference plate (40) as the coordinate reference, scan the existing beam and slab reinforcement (21) around the cover structure column (10), and collect and generate a point cloud data model containing the actual arrangement information of the reinforcement. Step S3: BIM Model Construction and Collaboration: Import the point cloud data model into BIM modeling software to construct a three-dimensional BIM model of the existing structure; at the same time, import the design drawing information of the continued column (30) into the same BIM modeling software to generate a design BIM model of the continued column (30); through unified alignment of the coordinate system, accurately match the spatial position of the design BIM model with the three-dimensional BIM model of the existing structure. Step S4: Rebar Installation (32) Parametric Layout and Collision Detection: In the BIM modeling software, according to the design requirements, the rebar model to be installed is parametrically arranged in the connection area (301) between the existing structure's 3D BIM model and the design BIM model; after the arrangement is completed, the collision detection function of the BIM modeling software is activated to perform collision detection between the rebar to be installed in the rebar model and the original rebar in the existing structure's 3D BIM model, and the rebar model to be installed is optimized based on the collision detection results; Step S5: Construction information output and on-site implementation: Based on the optimized and adjusted model of the rebar to be installed, output a construction guidance document containing the location coordinates, specifications, depth and arrangement information of the rebar (32); on-site construction personnel carry out drilling and rebar (32) installation operations according to the construction guidance document.

2. The construction method according to claim 1, characterized in that, In step S1, the construction control line is a line extending outward 450-550mm from the edge of the cover structure column (10) as a reference; the reference plate (40) is an acrylic plate with millimeter scale.

3. The construction method according to claim 2, characterized in that, In step S1, when adjusting the reference plate (40) so that its edge is aligned with the construction control line, the alignment deviation is controlled to be no greater than 1mm.

4. The construction method according to claim 1, characterized in that, In step S1, before laying the reference plate (40), the building surface layer within the construction control line area is chiseled down to the structural floor slab elevation so that the actual arrangement of the existing beam and slab reinforcement (21) is fully exposed.

5. The construction method according to claim 1, characterized in that, In step S2, during the scanning process, after scanning a region of a preset width, the process is paused and the quality of the real-time generated point cloud data is checked. The scanning can only continue after confirming that the outline of the steel bars is clear and there is no missing data.

6. The construction method according to claim 1, characterized in that, In step S3, the positioning reference for the coordinate system alignment includes: the design center position of the cover structure column (10), the scale origin set on the reference plate (40), and the boundary of the construction control line; after alignment, the coordinate deviation between models is no greater than 1mm.

7. The construction method according to claim 1, characterized in that, In step S4, the parameterized arrangement of the rebar model to be planted includes defining the diameter, implantation depth, exposed length, row spacing and column spacing of the rebar (32).

8. The construction method according to claim 1, characterized in that, Step S4 further includes: If the collision detection finds that the insertion depth of the steel bar to be installed cannot meet the design requirements due to the obstruction of the existing structure, then record the design requirement depth and the actual implantable depth at that location. Based on the model of the steel reinforcement to be installed, the bearing capacity is verified, and a steel reinforcement node (302) in the form of an enlarged original column pier (31) is designed accordingly to meet the structural bearing capacity requirements.

9. The construction method according to claim 1, characterized in that, Step S5 further includes: during the construction of rebar (32), measuring the actual rebar (32) parameters and comparing them with the corresponding theoretical values ​​in the model of the rebar to be installed, calculating the coordinate error, size error and depth error; recording the error data in the database for data support for the model accuracy control and optimization of subsequent similar constructions.

10. The construction method according to claim 1, characterized in that, In step S5, the output construction guidance document includes a plan view of the rebar (32) locations based on the coordinate system of the reference plate (40), a three-dimensional visualization view, a detailed sectional view, and a bill of quantities.

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