Method and device for correcting three-dimensional point cloud model of steel truss beam truss segment

Abstract

The application provides a three-dimensional point cloud model correction method and device for a steel truss beam truss segment, the method comprising: obtaining, through finite element analysis, linear displacement and angular displacement of each chord end head of the steel truss beam truss segment after conversion from a measurement temperature field to an assembly temperature field, and recording as first correction parameters; obtaining, through finite element analysis, linear displacement and angular displacement of each chord end head of the steel truss beam truss segment after conversion from a horizontal placement state to a hoisting state, and recording as second correction parameters; and in the three-dimensional point cloud model of the steel truss beam truss segment, performing coordinate correction on bolt hole groups on the chord end head according to the first correction parameters and the second correction parameters of each chord end head, wherein the three-dimensional point cloud model is established based on the steel truss beam truss segment in the measurement temperature field and the horizontal placement state. The application performs temperature correction and stress correction on the three-dimensional point cloud model, and the corrected three-dimensional point cloud model can realize more accurate virtual pre-assembly.

Description

Technical Field

[0001] This application relates to the field of intelligent bridge construction technology, specifically to a method and device for correcting a three-dimensional point cloud model of a steel truss girder segment. Background Technology

[0002] Due to the terrain limitations of mountainous areas, such as steep slopes and limited space, it is difficult to stack and transport components, making large-scale physical assembly of steel truss segments challenging. Therefore, virtual pre-assembly using computer technology and 3D scanning technology can improve assembly efficiency, shorten construction time, save space, reduce friction surface damage, predict and optimize the steel beam assembly alignment, reduce errors, achieve overall optimal performance, improve segment assembly accuracy, and control assembly quality. This can address the need for bolted assembly of large segments of steel truss girders in long-span suspension bridges in mountainous areas.

[0003] In related technologies, a 3D point cloud model of a steel truss segment is obtained by scanning and reverse-engineering the bolt hole groups at the ends of each chord member. Compared to previous BIM (Building Information Modeling), this 3D point cloud model can account for errors generated during manufacturing and installation, and is closer to the actual truss segment structure. However, when this 3D point cloud model is used for virtual pre-assembly, it ignores the effects of temperature and stress changes, resulting in insufficient accuracy. Summary of the Invention

[0004] This application provides a method and apparatus for correcting the three-dimensional point cloud model of a steel truss segment, which can solve the technical problem of insufficient accuracy of the three-dimensional point cloud model of the steel truss segment when used for virtual pre-assembly in the prior art.

[0005] In a first aspect, embodiments of this application provide a method for correcting a three-dimensional point cloud model of a steel truss girder segment, the method comprising:

[0006] The linear and angular displacements of each chord end of the steel truss segment after the temperature field was converted from the measured temperature field to the assembly temperature field were obtained by finite element analysis and denoted as the first correction parameter.

[0007] The linear and angular displacements of each chord end of the steel truss girder segment after it is changed from a horizontally placed state to a hoisted state are obtained by finite element analysis and are denoted as the second correction parameter.

[0008] In the three-dimensional point cloud model of the steel truss girder segment, the coordinates of the bolt hole group on the end of the chord are corrected according to the first correction parameter and the second correction parameter of each chord end. The three-dimensional point cloud model is based on the steel truss girder segment in the measured temperature field and in a horizontal placement state.

[0009] Furthermore, in one embodiment, the step of obtaining the linear and angular displacements of each chord end of the steel truss segment after the temperature field is converted from the measured temperature field to the assembly temperature field through finite element analysis includes:

[0010] In the finite element model of the steel truss segment, the initial temperature is set to 0℃, the final temperature is set to the measured temperature value, and a temperature load is applied to obtain the first coordinate of the preset node at the end of each chord.

[0011] In the finite element model of the steel truss segment, the initial temperature is set to 0℃ and the final temperature is set to the assembly temperature value. Temperature load is applied to obtain the second coordinates of the preset nodes at the end of each chord.

[0012] For each chord end, the linear and angular displacements caused by the temperature field change are calculated based on the corresponding first and second coordinates.

[0013] Furthermore, in one embodiment, the step of obtaining the linear and angular displacements of each chord end of the steel truss girder segment after its transition from a horizontally placed state to a hoisted state through finite element analysis includes:

[0014] In the finite element model of the steel truss segment, the load and boundary conditions corresponding to the horizontal placement state are applied to obtain the third coordinate of the preset node at the end of each chord.

[0015] In the finite element model of the steel truss segment, the load and boundary conditions corresponding to the hoisting state are applied to obtain the fourth coordinate of the preset node in each chord end;

[0016] For each chord end, the linear and angular displacements caused by the change in force state are calculated based on the corresponding third and fourth coordinates.

[0017] Further, in one embodiment, the step of correcting the coordinates of the bolt hole group on the chord end according to the first correction parameter and the second correction parameter of each chord end includes:

[0018] For each bolt hole in the bolt hole group on each chord end, the coordinate change of the bolt hole is calculated based on the first correction parameter, the second correction parameter of the chord end and the position of the bolt hole in the chord end, and the coordinate change is superimposed on the original coordinate of the bolt hole.

[0019] Furthermore, in one embodiment, the bolt hole group at the end of each chord of the steel truss girder segment is scanned and three-dimensional reverse modeled, and the feature holes in the bolt hole group are spatially located to obtain a three-dimensional point cloud model.

[0020] Secondly, embodiments of this application also provide a three-dimensional point cloud model correction device for a steel truss girder segment, the three-dimensional point cloud model correction device for the steel truss girder segment comprising:

[0021] The first analysis module is used to obtain the linear and angular displacements of each chord end of the steel truss segment after the temperature field is converted from the measurement temperature field to the assembly temperature field through finite element analysis, and is denoted as the first correction parameter.

[0022] The second analysis module is used to obtain the linear and angular displacements of each chord end of the steel truss girder segment after it is transformed from a horizontally placed state to a hoisted state through finite element analysis, and these displacements are denoted as the second correction parameters.

[0023] The correction module is used to correct the coordinates of the bolt hole group at the end of each chord member in the three-dimensional point cloud model of the steel truss segment according to the first correction parameter and the second correction parameter of each chord member end. The three-dimensional point cloud model is based on the steel truss segment in a measured temperature field and in a horizontally placed state.

[0024] Furthermore, in one embodiment, the first analysis module is used to:

[0025] In the finite element model of the steel truss segment, the initial temperature is set to 0℃, the final temperature is set to the measured temperature value, and a temperature load is applied to obtain the first coordinate of the preset node at the end of each chord.

[0026] In the finite element model of the steel truss segment, the initial temperature is set to 0℃ and the final temperature is set to the assembly temperature value. Temperature load is applied to obtain the second coordinates of the preset nodes at the end of each chord.

[0027] For each chord end, the linear and angular displacements caused by the temperature field change are calculated based on the corresponding first and second coordinates.

[0028] Furthermore, in one embodiment, the second analysis module is used for:

[0029] In the finite element model of the steel truss segment, the load and boundary conditions corresponding to the horizontal placement state are applied to obtain the third coordinate of the preset node at the end of each chord.

[0030] In the finite element model of the steel truss segment, the load and boundary conditions corresponding to the hoisting state are applied to obtain the fourth coordinate of the preset node in each chord end;

[0031] For each chord end, the linear and angular displacements caused by the change in force state are calculated based on the corresponding third and fourth coordinates.

[0032] Furthermore, in one embodiment, the correction module is used to:

[0033] For each bolt hole in the bolt hole group on each chord end, the coordinate change of the bolt hole is calculated based on the first correction parameter, the second correction parameter of the chord end and the position of the bolt hole in the chord end, and the coordinate change is superimposed on the original coordinate of the bolt hole.

[0034] Furthermore, in one embodiment, the bolt hole group at the end of each chord of the steel truss girder segment is scanned and three-dimensional reverse modeled, and the feature holes in the bolt hole group are spatially located to obtain a three-dimensional point cloud model.

[0035] This application assumes that the ends of the chord members are rigid bodies, considering only their overall linear and angular displacements as correction parameters for the bolt hole group, while ignoring the relative deformation of individual points within them, thus ensuring computational accuracy and the feasibility of finite element analysis. This application uses finite element analysis to examine the deformation of steel truss segments as they transition from the measured temperature field to the assembly temperature field, and as their deformation as they transition from a horizontal placement state to a hoisting state. This allows for temperature and stress correction of the 3D point cloud model, resulting in a more accurate virtual pre-assembly. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating a method for correcting a three-dimensional point cloud model of a steel truss girder segment in one embodiment of this application.

[0037] Figure 2 This is a schematic diagram of the angular and linear displacements at the ends of the chord members;

[0038] Figure 3 This is a schematic diagram of the forces acting on a steel truss segment when it is placed horizontally.

[0039] Figure 4 This is a schematic diagram of the forces acting on a steel truss segment during hoisting.

[0040] Figure 5 This is a schematic diagram of the functional modules of the three-dimensional point cloud model correction device for a steel truss segment in one embodiment of this application.

[0041] The attached figures are labeled as follows:

[0042] 10. Top chord; 11. Top chord end; 12. Suspension point; 20. Bottom chord; 21. Bottom chord end. Detailed Implementation

[0043] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0044] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0045] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0046] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0047] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0049] In one aspect, embodiments of this application provide a method for correcting a three-dimensional point cloud model of a steel truss segment.

[0050] Figure 1 A flowchart illustrating a method for correcting a three-dimensional point cloud model of a steel truss segment according to an embodiment of this application is shown.

[0051] Reference Figure 1 In one embodiment, the method for correcting the three-dimensional point cloud model of a steel truss segment includes the following steps:

[0052] S11. The linear and angular displacements of each chord end of the steel truss segment after the temperature field is converted from the measured temperature field to the assembly temperature field are obtained through finite element analysis and are denoted as the first correction parameter.

[0053] The measured temperature field refers to the temperature field of the truss segment when point cloud data is collected, while the assembly temperature field refers to the temperature field of the truss segment when it is expected to be assembled. The difference between the two temperature fields will cause corresponding deformations, making the 3D point cloud model unsuitable for direct use in virtual pre-assembly and requiring temperature correction. Point cloud data is typically collected in the early morning when temperatures are lower, as the deformation of the truss segment is less affected by temperature changes, and the temperature field of the truss segment can be considered a uniform temperature field. All measurements are then quickly completed, and the relevant parameters of the measured temperature field are recorded. The relevant parameters of the assembly temperature field are determined based on temperature observation records at the bridge site.

[0054] Figure 2 A schematic diagram of the angular and linear displacements at the ends of the chord is shown.

[0055] The internal deformation of the chord ends accounts for a small proportion of the overall deformation of the truss segment. During virtual pre-assembly, the main focus is on the impact of the overall position and angle changes of the chord ends on the spatial coordinates of the bolt hole group. Therefore, while ensuring assembly accuracy, the chord ends can be considered as rigid bodies, considering only their overall linear and angular displacements, ignoring the relative deformations of their internal points. A finite element model of the truss segment is established using the design drawings, and a corresponding temperature field is applied. When extracting the calculation results, only the linear and angular displacements of the eight chord ends of the truss segment caused by temperature field changes are extracted. Figure 2 The linear and angular displacements in the x, y, and z directions are shown, and these are used to perform temperature correction on the 3D point cloud model.

[0056] For example, in the finite element model of a steel truss segment, the initial temperature is set to 0℃, and the final temperature is set to the measured temperature value. A temperature load is applied, and the first coordinates of the preset nodes at each chord end are obtained. Similarly, in the finite element model of the steel truss segment, the initial temperature is set to 0℃, and the final temperature is set to the assembly temperature value. A temperature load is applied, and the second coordinates of the preset nodes at each chord end are obtained. For each chord end, the linear and angular displacements caused by the temperature field change are calculated based on the corresponding first and second coordinates.

[0057] It should be noted that the preset nodes at the ends of the chords are determined based on the actual mesh division of the finite element model, and the linear and angular displacements at the ends of the chords caused by the temperature field changes are calculated based on the coordinate changes of the preset nodes.

[0058] S12. The linear and angular displacements of each chord end of the steel truss girder segment after it is changed from a horizontally placed state to a hoisted state are obtained through finite element analysis and are denoted as the second correction parameter.

[0059] Figure 3 A schematic diagram of the forces acting on a steel truss segment in a horizontally placed state is shown. Figure 4 A schematic diagram of the forces acting on a steel truss segment during hoisting is shown.

[0060] Reference Figure 3 When collecting point cloud data, the truss segments are placed horizontally in the assembly yard. The bottom of the truss segments has supports for support and constraint. The truss segments are mainly subjected to their own weight and the supporting force of the piers. (Refer to...) Figure 4 During assembly, the crane lifts the truss segment via lifting points 12 on the upper chord 10. The truss segment is mainly subjected to its own weight and the tension at the four lifting points 12. The difference between these two stress states will cause corresponding deformation, making the 3D point cloud model unsuitable for direct virtual pre-assembly and requiring stress correction. In addition, due to the height difference between the horizontal ground and the mid-lift, the horizontal wind load on the truss will also differ to some extent. However, the deformation effect caused by this difference is relatively small compared to the deformation effect caused by the support force and tension, and can be selectively ignored.

[0061] Similar to step S11, the ends of the chord members are treated as rigid bodies, considering only their overall linear and angular displacements while ignoring the relative deformations of their internal points. Corresponding external forces are applied to the finite element model. When extracting the calculation results, only the linear and angular displacements of the eight chord ends of the truss segment caused by changes in force are extracted, thus correcting the force on the three-dimensional point cloud model.

[0062] For example, in the finite element model of a steel truss segment, loads and boundary conditions corresponding to the horizontal placement state are applied to obtain the third coordinates of the preset nodes at each chord end. In the finite element model of the steel truss segment, loads and boundary conditions corresponding to the hoisting state are applied to obtain the fourth coordinates of the preset nodes at each chord end. For each chord end, the linear and angular displacements caused by the change in stress state are calculated based on the corresponding third and fourth coordinates.

[0063] It should be noted that the preset nodes at the ends of the chords are determined based on the actual mesh division of the finite element model, and the linear and angular displacements at the ends of the chords caused by changes in the force state are calculated based on the coordinate changes of the preset nodes.

[0064] S13. In the three-dimensional point cloud model of the steel truss segment, the coordinates of the bolt hole group at the end of the chord are corrected according to the first correction parameter and the second correction parameter of each chord end. The three-dimensional point cloud model is based on the steel truss segment in the measured temperature field and in a horizontal placement state.

[0065] In this embodiment, the first correction parameter is used to correct the coordinates of the bolt hole group by temperature, and the second correction parameter is used to correct the coordinates of the bolt hole group by force. The corrected coordinates of the bolt hole group take into account the errors generated during manufacturing and installation, as well as the effects of temperature and force changes, and are closer to the actual situation during assembly, thereby achieving more accurate virtual pre-assembly.

[0066] For example, for each bolt hole in the bolt hole group on each chord end, the coordinate change of the bolt hole is calculated based on the first correction parameter, the second correction parameter of the chord end and the position of the bolt hole in the chord end, and the coordinate change is superimposed on the original coordinate of the bolt hole.

[0067] Therefore, in this embodiment, the chord end is assumed to be a rigid body, and only its overall linear and angular displacements are considered as correction parameters for the bolt hole group, ignoring the relative deformation of each point inside, thus ensuring calculation accuracy and the feasibility of finite element analysis. This application uses finite element analysis to examine the deformation of the steel truss segment as it transitions from the measured temperature field to the assembly temperature field, and the deformation as it transitions from a horizontal placement state to a hoisting state. This allows for temperature and stress correction of the three-dimensional point cloud model, enabling more accurate virtual pre-assembly.

[0068] Furthermore, in one embodiment, the bolt hole group at the end of each chord of the steel truss girder segment is scanned and three-dimensional reverse modeled, and the feature holes in the bolt hole group are spatially located to obtain a three-dimensional point cloud model.

[0069] In this embodiment, a 3D scanner is used to scan and reverse model the bolt hole group at the end of the chord member. A laser tracker is used to spatially locate the feature holes in the bolt hole group at the end of the chord member. The refined point cloud models of each independent chord member end are combined with the spatial coordinates of the feature holes measured by the laser tracker to finally establish a 3D point cloud model containing the refined bolt hole group point cloud data. Compared with directly determining the bolt hole group coordinates from the point cloud data of 3D reverse modeling, the method of combining a 3D scanner and a laser tracker can obtain more accurate bolt hole group coordinates.

[0070] Secondly, embodiments of this application also provide a three-dimensional point cloud model correction device for steel truss girder segments.

[0071] Figure 5 A schematic diagram of the functional modules of a three-dimensional point cloud model correction device for a steel truss segment is shown in one embodiment of this application.

[0072] Reference Figure 5 In one embodiment, the three-dimensional point cloud model correction device for the steel truss segment includes:

[0073] The first analysis module 10 is used to obtain the linear and angular displacements of each chord end of the steel truss segment after the temperature field is converted from the measurement temperature field to the assembly temperature field through finite element analysis, and is denoted as the first correction parameter.

[0074] The second analysis module 20 is used to obtain the linear and angular displacements of each chord end after the steel truss segment is transformed from a horizontally placed state to a hoisted state through finite element analysis, and is denoted as the second correction parameter.

[0075] The correction module 30 is used to correct the coordinates of the bolt hole group at the end of the chord in the three-dimensional point cloud model of the steel truss segment according to the first correction parameter and the second correction parameter of each chord end. The three-dimensional point cloud model is established based on the steel truss segment in the measured temperature field and in a horizontal placement state.

[0076] Furthermore, in one embodiment, the first analysis module 10 is used for:

[0077] In the finite element model of the steel truss segment, the initial temperature is set to 0℃, the final temperature is set to the measured temperature value, and a temperature load is applied to obtain the first coordinate of the preset node at the end of each chord.

[0078] In the finite element model of the steel truss segment, the initial temperature is set to 0℃ and the final temperature is set to the assembly temperature value. Temperature load is applied to obtain the second coordinates of the preset nodes at the end of each chord.

[0079] For each chord end, the linear and angular displacements caused by the temperature field change are calculated based on the corresponding first and second coordinates.

[0080] Furthermore, in one embodiment, the second analysis module 20 is used for:

[0081] In the finite element model of the steel truss segment, the load and boundary conditions corresponding to the horizontal placement state are applied to obtain the third coordinate of the preset node at the end of each chord.

[0082] In the finite element model of the steel truss segment, the load and boundary conditions corresponding to the hoisting state are applied to obtain the fourth coordinate of the preset node at the end of each chord.

[0083] For each chord end, the linear and angular displacements caused by the change in force state are calculated based on the corresponding third and fourth coordinates.

[0084] Furthermore, in one embodiment, the correction module 30 is used to:

[0085] For each bolt hole in the bolt hole group on each chord end, the coordinate change of the bolt hole is calculated based on the first correction parameter, the second correction parameter of the chord end and the position of the bolt hole in the chord end, and the coordinate change is superimposed on the original coordinate of the bolt hole.

[0086] Furthermore, in one embodiment, the bolt hole group at the end of each chord of the steel truss girder segment is scanned and three-dimensional reverse modeled, and the feature holes in the bolt hole group are spatially located to obtain a three-dimensional point cloud model.

[0087] The functions of each module in the above-mentioned three-dimensional point cloud model correction device for steel truss segments correspond to the steps in the above-mentioned three-dimensional point cloud model correction method embodiment for steel truss segments, and their functions and implementation processes will not be described in detail here.

[0088] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0089] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for correcting a three-dimensional point cloud model of a steel truss segment, characterized in that, The three-dimensional point cloud model correction method of the steel truss girder truss section comprises: The linear displacement and angular displacement of each chord end of the steel truss girder truss section after the steel truss girder truss section is converted from a measured temperature field to an assembly temperature field are obtained through finite element analysis, and are recorded as first correction parameters, wherein the measured temperature field is a temperature field in which the truss section is located when the point cloud data is collected, and the assembly temperature field is a temperature field in which the truss section is located when the truss section is assembled; The linear displacement and angular displacement of each chord end of the steel truss girder truss section after the steel truss girder truss section is converted from a horizontal placement state to a hoisting state are obtained through finite element analysis, and are recorded as second correction parameters; In the three-dimensional point cloud model of the steel truss girder truss section, the bolt hole groups on the chord ends are corrected according to the first correction parameters and the second correction parameters of each chord end, wherein the three-dimensional point cloud model is established based on the steel truss girder truss section in the measured temperature field and the horizontal placement state; The step of obtaining the linear displacement and angular displacement of each chord end of the steel truss girder truss section after the steel truss girder truss section is converted from a measured temperature field to an assembly temperature field through finite element analysis comprises: In the finite element model of the steel truss girder truss section, the initial temperature is set to 0℃, the final temperature is set to the measured temperature value, and the temperature load is applied to obtain the first coordinates of the preset nodes in each chord end; In the finite element model of the steel truss girder truss section, the initial temperature is set to 0℃, the final temperature is set to the assembly temperature value, and the temperature load is applied to obtain the second coordinates of the preset nodes in each chord end; For each chord end, the linear displacement and angular displacement caused by the change of the temperature field are calculated according to the corresponding first coordinates and second coordinates; The step of obtaining the linear displacement and angular displacement of each chord end of the steel truss girder truss section after the steel truss girder truss section is converted from a horizontal placement state to a hoisting state through finite element analysis comprises: In the finite element model of the steel truss girder truss section, the corresponding load and boundary conditions of the horizontal placement state are applied to obtain the third coordinates of the preset nodes in each chord end; In the finite element model of the steel truss girder truss section, the corresponding load and boundary conditions of the hoisting state are applied to obtain the fourth coordinates of the preset nodes in each chord end; For each chord end, the linear displacement and angular displacement caused by the change of the stress state are calculated according to the corresponding third coordinates and fourth coordinates.

2. The method of claim 1, wherein the method further comprises: The step of correcting the coordinates of the bolt hole groups on the chord ends according to the first correction parameters and the second correction parameters of each chord end comprises: For each bolt hole in the bolt hole groups on each chord end, the coordinate change amount of the bolt hole is calculated according to the first correction parameters, the second correction parameters of the chord end, and the position of the bolt hole in the chord end, and the coordinate change amount is added to the original coordinates of the bolt hole.

3. The method of claim 1 or 2, wherein The three-dimensional point cloud model is obtained by scanning and three-dimensional reverse modeling of the bolt hole groups of each chord end of the steel truss girder truss section and spatial positioning of the feature holes in the bolt hole groups.

4. A device for correcting a three-dimensional point cloud model of a steel truss girder segment, characterized by The three-dimensional point cloud model correction device of the steel truss girder truss section comprises: A first analysis module is configured to obtain the linear displacement and angular displacement of each chord end of the steel truss girder truss section after the steel truss girder truss section is converted from a measured temperature field to an assembly temperature field through finite element analysis, and record the linear displacement and angular displacement as first correction parameters, wherein the measured temperature field is a temperature field in which the truss section is located when the point cloud data is collected, and the assembly temperature field is a temperature field in which the truss section is located when the truss section is assembled; The second analysis module is configured to obtain linear displacement and angular displacement of each chord end head of the steel truss girder section after the steel truss girder section is converted from the horizontal placement state to the hoisting state through finite element analysis, and the linear displacement and the angular displacement are denoted as second correction parameters; The correction module is configured to correct coordinates of bolt hole groups on the chord end head according to the first correction parameter and the second correction parameter of each chord end head in the three-dimensional point cloud model of the steel truss girder section, wherein the three-dimensional point cloud model is established based on the steel truss girder section in the measurement temperature field and the horizontal placement state; The first analysis module is configured to: set an initial temperature as 0℃ and a final temperature as a measurement temperature value in the finite element model of the steel truss girder section, apply a temperature load, and obtain first coordinates of preset nodes in each chord end head; set an initial temperature as 0℃ and a final temperature as an assembly temperature value in the finite element model of the steel truss girder section, apply a temperature load, and obtain second coordinates of preset nodes in each chord end head; for each chord end head, calculate linear displacement and angular displacement caused by a change in the temperature field according to the corresponding first coordinates and the second coordinates; The second analysis module is configured to: apply a load and a boundary condition corresponding to the horizontal placement state in the finite element model of the steel truss girder section, and obtain third coordinates of preset nodes in each chord end head; apply a load and a boundary condition corresponding to the hoisting state in the finite element model of the steel truss girder section, and obtain fourth coordinates of preset nodes in each chord end head; for each chord end head, calculate linear displacement and angular displacement caused by a change in a stress state according to the corresponding third coordinates and the fourth coordinates.

5. The apparatus for correcting a three-dimensional point cloud model of a steel truss beam truss segment of claim 4, wherein, The correction module is configured to: for each bolt hole in the bolt hole group of each chord end head, calculate a coordinate change amount of the bolt hole according to the first correction parameter and the second correction parameter of the chord end head and a position of the bolt hole in the chord end head, and add the coordinate change amount to an original coordinate of the bolt hole.

6. The device for correcting a three-dimensional point cloud model of a steel truss beam truss segment according to claim 4 or 5, characterized in that, The bolt hole group of each chord end head of the steel truss girder section is scanned and three-dimensional reverse modeling is performed, and a feature hole in the bolt hole group is spatially positioned to obtain the three-dimensional point cloud model.

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