High-precision assembling method for large-span steel corridor structure

Abstract

The invention provides a large-span steel corridor structure high-precision assembling method, and belongs to the technical field of building construction, and the method comprises the step of constructing an accurate and reliable structure assembling technical system through deep fusion of a building information model and a three-dimensional space coordinate system. According to the method, a laser positioning instrument and a multi-stage torque sensor are introduced for the first time, and accurate positioning of the steel member and fine control of bolt torque are achieved. From a pre-assembly site, component installation is conducted layer by layer through an axis control net and an angular point control net, and a staged bolt fastening strategy is adopted and comprises initial tightening torque control, semi-tightening torque control and final tightening torque control. In the assembling process, finite element analysis software is used for conducting multiple times of structure checking calculation, the space position error and the structure stability are strictly monitored, and the geometric accuracy, the connection reliability and the overall performance of the large-span steel corridor structure are ensured. According to the method, the problem that large accumulative errors are inevitably caused by the fact that manual measurement and mechanical limiting modes are generally adopted for positioning and connection at present is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of building construction, and in particular relates to a high-precision assembly method for a large-span steel corridor structure. Background Art

[0002] As a special form of steel structure, the large-span steel corridor structure is widely used in large public buildings, such as stadiums, exhibition halls, station hubs, etc. Compared with the traditional beam-column structure, this structure has the advantages of large span, wide column spacing, and high space utilization. However, due to the complex node connection and high assembly precision requirements of components, its construction process has always been a difficult problem that the industry has paid attention to.

[0003] At present, the assembly processes of large-span steel corridor structures are mainly the following:

[0004] 1. Overall prefabrication method. The entire structure is prefabricated in the factory and then hoisted to the site as a whole. This method can ensure the integrity of the structure and the reliability of the connection, but it is difficult to achieve a super-large span due to the limited size of the components. At the same time, there are many difficulties in transportation and hoisting, and the cost is high.

[0005] 2. Segmented prefabrication method. The entire structure is divided into several detachable large sections, which are prefabricated in the factory and then transported and hoisted in sections. This method reduces the size and weight of individual components, but the node connection between the large sections is still a key issue, and it is difficult to ensure sufficient installation accuracy.

[0006] 3. Single-piece assembly method. The entire structure is further divided into more single components, which are assembled step by step on site. This method can meet the needs of ultra-large spans, but due to the large number of components, the workload of on-site positioning and connection is large, and the cost and construction period are high.

[0007] Although the above three methods have their own advantages and disadvantages, they all have a common problem, that is, it is difficult to ensure the installation accuracy of the overall structure. At present, manual measurement and mechanical limit are generally used for positioning and connection, which inevitably leads to large cumulative errors. This will not only affect the overall stability of the structure, but also increase the workload of subsequent maintenance and adjustment.

[0008] To address this problem, the present invention proposes a high-precision assembly method for large-span steel corridor structures. This method makes full use of advanced technologies such as digital modeling and spatial positioning, establishes a complete three-dimensional control system, and adopts a connection strategy of multi-level torque control, which greatly improves the installation accuracy and connection reliability of the assembly process. Summary of the invention

[0009] In view of this, the present invention provides a high-precision assembly method for a large-span steel corridor structure, which can solve the problem of large cumulative errors that are inevitably caused by the current common use of manual measurement and mechanical limiting methods for positioning and connection.

[0010] The present invention is achieved in that:

[0011] The present invention provides a high-precision assembly method for a large-span steel corridor structure, comprising the following steps:

[0012] S10, digitally modeling the large-span steel corridor structure using a building information model, constructing a spatial three-dimensional coordinate system, positioning each component of the large-span steel corridor structure in the spatial three-dimensional coordinate system, and forming an axis control network and a corner point control network;

[0013] S20, arranging the initial positions of the steel components at the pre-assembly site according to the three-dimensional spatial coordinate system, using a laser locator to initially calibrate the steel components, and comparing the positions of the steel components with the axis control network and the corner point control network in the three-dimensional spatial coordinate system;

[0014] S30, importing the building information model of the large-span steel corridor structure into finite element analysis software, and performing preliminary structural verification on the large-span steel corridor structure;

[0015] S40, installing a multi-stage torque sensor at the bolt connection position of the large-span steel corridor structure, and calculating the initial tightening torque value, half tightening torque value and final tightening torque value of the bolt by using a restraining torque equation according to the strength and nominal diameter of the bolt;

[0016] S50, when installing a single steel beam component, tighten the bolts to the initial tightening torque value, and re-measure and check the corner point control network after completing the installation of each beam in the uniaxial direction;

[0017] S60, after completing the installation of the steel beam components of each layer, re-measure and check using the axis control network, and increase the pre-tightening force of all the connecting bolts of this layer to the semi-tightening torque value;

[0018] S70, installing the last layer of steel beam chords and supporting structures, using the laser positioning device to perform positioning scanning, and verifying the spatial position in the three-dimensional spatial coordinate system;

[0019] S80, after the spatial position meets the design error standard, the pre-tightening force of all bolts in the large-span steel corridor structure is increased to the final tightening torque value;

[0020] S90. Use the finite element analysis software to perform final structural verification on the installed large-span steel corridor structure, review the overall stability and stress distribution of the structure, and after confirming that all indicators meet the design requirements, conduct final acceptance to complete the entire assembly process.

[0021] Furthermore, the step S10 specifically includes:

[0022] Step 101, obtaining the design drawings of the large-span steel corridor structure, and extracting the geometric size information, material information and node connection information of the large-span steel corridor structure;

[0023] Step 102: Use building information modeling software to create a three-dimensional model of the long-span steel corridor structure, and mark the component numbers, installation sequence and connection methods in the three-dimensional model;

[0024] Step 103, establishing the spatial three-dimensional coordinate system based on the three-dimensional model, and setting the origin of the spatial three-dimensional coordinate system at the reference point of the large-span steel corridor structure;

[0025] Step 104, establishing the axis control network in the three-dimensional spatial coordinate system, and setting the main control points of the axis control network at the key node positions of the large-span steel corridor structure;

[0026] Step 105: Establish the corner point control network in the three-dimensional spatial coordinate system, and set the control points of the corner point control network at the four corners of each component of the long-span steel corridor structure.

[0027] Furthermore, the step S20 specifically includes:

[0028] Step 201: setting a plurality of reference points at the pre-assembly site according to the spatial three-dimensional coordinate system, and determining the spatial coordinates of the reference points by measuring with a total station;

[0029] Step 202, dividing the pre-assembly area according to the reference point, and marking the component storage position and the lifting channel in the pre-assembly area;

[0030] Step 203, installing the laser locator at the reference point, and determining the instrument coordinates of the laser locator using the resection method;

[0031] Step 204: Use the laser positioning device to perform three-dimensional scanning on each steel component to obtain the actual spatial coordinates of each steel component;

[0032] Step 205: Compare and analyze the actual space coordinates with the axis control network and the corner point control network to generate deviation data.

[0033] Furthermore, the step S30 specifically includes:

[0034] Step 301: convert the building information model into a finite element analysis model, and determine the unit type and mesh division density;

[0035] Step 302: input the boundary conditions of the large-span steel corridor structure, including support constraint conditions and node connection methods;

[0036] Step 303, applying a load combination, including a dead load, a live load, a wind load and a temperature load;

[0037] Step 304: Calculate the stress distribution and deformation of the large-span steel corridor structure using a linear static analysis method;

[0038] Step 305: Verify the calculation results according to the specification requirements to ensure that the strength, stiffness and stability meet the design requirements.

[0039] Furthermore, the step S40 specifically includes:

[0040] Step 401, installing a magnetic torque sensor at the bolt connection position, and connecting the torque sensor to a data acquisition system;

[0041] Step 402: Determine the tensile strength of the bolt according to its material grade, and calculate the stress-bearing area of ​​the bolt according to its nominal diameter;

[0042] Step 403: Substitute the tensile strength, the force-bearing area and the friction coefficient into the restraining moment equation;

[0043] Step 404: Calculate the initial tightening torque value, the half tightening torque value and the final tightening torque value through the locking torque equation.

[0044] Furthermore, the step S50 specifically includes:

[0045] Step 501, before installing a single steel beam component, check the correspondence between the connecting plate and the bolt hole;

[0046] Step 502: using a temporary fixing device to position the single steel beam component at a designed position;

[0047] Step 503, installing the bolts and tightening the bolts to the initial tightening torque value using a torque wrench;

[0048] Step 504: using the torque sensor to detect the actual torque value of the bolt to ensure that the error between the actual torque value and the initial tightening torque value is within an allowable range;

[0049] Step 505: After completing the installation of each frame in the single-axis direction, use the laser locator to measure the spatial coordinates of the corner point control network;

[0050] Step 506: Compare the measured coordinates with the designed coordinates to ensure that the installation accuracy meets the requirements.

[0051] Furthermore, the step S60 specifically includes:

[0052] Step 601, using the laser positioning device to measure the spatial position of each layer of steel beam components after installation;

[0053] Step 602, importing the measurement data into a computer and automatically comparing it with the axis control network;

[0054] Step 603, calculating the spatial coordinate deviation of each control point and generating a deviation distribution cloud map;

[0055] Step 604: perform overall adjustment according to the deviation distribution cloud map to eliminate systematic errors;

[0056] Step 605: After the adjustment is completed, the pre-tightening force of all the connecting bolts of the layer is increased to the semi-tightening torque value using a torque wrench;

[0057] Step 606: Use the torque sensor to review and confirm the semi-tightening torque value.

[0058] Furthermore, the step S70 specifically includes:

[0059] Step 701, install the last layer of steel beam chords, and adjust their spatial position until they match the lower structure;

[0060] Step 702: Install the support structure to ensure that it is tightly connected to the main structure;

[0061] Step 703: Use the laser positioning device to perform three-dimensional scanning on the entire structure;

[0062] Step 704: performing noise reduction and registration processing on the scanned point cloud data;

[0063] Step 705: convert the processed point cloud data into a three-dimensional model;

[0064] Step 706: Perform spatial position analysis on the three-dimensional model in the spatial three-dimensional coordinate system.

[0065] Furthermore, the step S80 specifically includes:

[0066] Step 801, comparing the spatial position analysis result with the design error standard;

[0067] Step 802, prepare a bolt final tightening torque construction plan and determine the bolt tightening sequence;

[0068] Step 803, final tightening of bolts in different areas according to the construction plan;

[0069] Step 804: using a torque wrench to increase the bolt pre-tightening force to the final tightening torque value;

[0070] Step 805: using the torque sensor to check the final tightening torque value;

[0071] Step 806: Record and archive the final tightening torque detection data of each bolt.

[0072] Furthermore, the step S90 specifically includes:

[0073] Step 901: Acquire the actual geometric model of the large-span steel corridor structure by three-dimensional scanning;

[0074] Step 902: Compare the actual geometric model with the original finite element analysis model and update geometric parameters;

[0075] Step 903, reapplying the load combination, including the measured dead load and the designed live load;

[0076] Step 904: Perform structural calculation using a nonlinear analysis method;

[0077] Step 905: Analyze stress distribution, deformation and natural frequency to evaluate the overall performance of the structure;

[0078] Step 906: After confirming that all indicators meet the design requirements, final acceptance and data archiving are carried out to complete the entire assembly process.

[0079] The calculation process involved in the steps of the present invention is described in detail as follows:

[0080] 1. Calculation of the spatial three-dimensional coordinate transformation matrix in step S10:

[0081] The spatial three-dimensional coordinate transformation matrix is ​​specifically expressed as follows:

[0082]

[0083] Where T is the homogeneous transformation matrix; R 3×3 is the rotation matrix; t 3×1 is the translation vector; 0 1×3 is the zero vector.

[0084] Rotation matrix R 3×3 The specific expressions are as follows:

[0085]

[0086] Where θ is the pitch angle, ranging from [-π / 2, π / 2]; φ is the roll angle, ranging from [-π, π]; ψ is the yaw angle, ranging from [-π, π].

[0087] 2. Structural static analysis equation in step S30:

[0088] The structural static analysis equation is specifically expressed as follows:

[0089] KU=F+ΔF;

[0090] Where K is the structural stiffness matrix; U is the node displacement vector; F is the external load vector; ΔF is the additional force vector considering geometric nonlinearity.

[0091] The structural stiffness matrix K is specifically expressed as follows:

[0092]

[0093] In the formula, k i is the stiffness coefficient of the ith unit; T i is the coordinate transformation matrix of the i-th unit; D i is the elastic matrix of the ith unit; B i is the strain matrix of the ith element; n is the total number of elements.

[0094] 3. Bolt locking torque equation in step S40:

[0095] The bolt locking torque equation is specifically expressed as follows:

[0096]

[0097] Where M t is the final tightening torque value; F p is the axial preload; P is the thread pitch; μ1 is the friction coefficient of the thread contact surface, and its value range is [0.1, 0.2]; μ2 is the friction coefficient of the nut support surface, and its value range is [0.1, 0.2]; d2 is the thread median diameter; D n is the equivalent friction diameter of the nut bearing surface; α is the thread half angle, the standard value is 30°; η is the torque loss coefficient, the value range is [0.1,0.15].

[0098] 4. Calculation of spatial position error in step S70:

[0099] The spatial position error calculation is specifically expressed as follows:

[0100]

[0101] Where, E is the comprehensive position error; Δx i ,Δyi ,Δz i are the linear errors of the i-th control point in three directions; Δθ j ,Δφ j ,Δψ j are the three rotation angle errors of the jth component; λ is the angle error weight coefficient; m is the number of control points; and n is the number of components.

[0102] 5. Structural stability verification in step S90:

[0103] The structural stability verification is specifically expressed as follows:

[0104] (λK e +K g )U=0;

[0105] Where λ is the eigenvalue; K e is the elastic stiffness matrix; K g is the geometric stiffness matrix; U is the displacement vector.

[0106] The calculation of critical buckling load factor is specifically expressed as follows:

[0107]

[0108] In the formula, λ cr is the critical buckling load factor; i is the i-th order eigenvalue; γ is the influence coefficient, and its value range is [0.05, 0.1]; ε j is the initial defect of the jth component; p is the number of components with defects considered.

[0109] The main principles and significance of the above equations are explained as follows:

[0110] 1. The spatial three-dimensional coordinate transformation matrix adopts the homogeneous transformation form, which can uniformly handle rotation and translation transformations. The rotation matrix adopts the Euler angle representation method, which can fully describe the spatial posture;

[0111] 2. The structural static analysis equation is based on finite element theory, taking into account the influence of geometric nonlinearity, and constructing the overall stiffness matrix by decomposition and assembly;

[0112] 3. The bolt locking torque equation takes into account thread friction, bearing surface friction and torque loss, and calculates the total torque by sub-item superposition;

[0113] 4. The spatial position error calculation adopts the weighted combination of linear error and angular error, which can comprehensively evaluate the installation accuracy;

[0114] 5. The structural stability verification is based on the eigenvalue buckling theory, while taking into account the influence of initial defects, which can more accurately predict structural instability.

[0115] The advantages of these equations are mainly reflected in: 1. The introduction of error terms and weight coefficients improves the calculation accuracy; 2. Nonlinear factors and initial defects are taken into account, which is more in line with engineering practice; 3. A multi-level torque control strategy is adopted to ensure connection reliability; 4. A comprehensive error evaluation system is established to facilitate quality control.

[0116] Compared with the prior art, the high-precision assembly method of a large-span steel corridor structure provided by the present invention has the following beneficial effects:

[0117] 1. A complete three-dimensional digital control system has been established. Through the construction of the building information model and the three-dimensional spatial coordinate system, all-round digital modeling and positioning of the entire structure have been achieved. Not only can the component size and assembly sequence be optimized during the design phase, but also precise measurement methods such as laser locators can be used during on-site construction to greatly improve the accuracy of installation positioning.

[0118] 2. A multi-level torque-controlled bolt connection strategy is adopted. A torque sensor is installed at the connection position, and the torque values ​​of the three stages of initial tightening, semi-tightening and final tightening are calculated according to the strength characteristics of the bolt. By applying the pre-tightening force in steps, not only the connection reliability of the overall structure is guaranteed, but also the installation deviation of each component can be effectively controlled.

[0119] 3. The whole process of structural installation accuracy detection and correction is realized. In addition to the initial positioning, the control network re-test is used to check and correct the deviation after each layer of components is installed. For the last layer of structure, the overall position is fully verified using 3D scanning technology. This ensures that the installation accuracy of each part of the structure meets the design requirements.

[0120] 4. A complete structural performance verification system has been established. Finite element analysis is used to evaluate the structural stress conditions in the preliminary design stage, and after the final installation is completed, nonlinear analysis is carried out based on the actual geometric model to ensure that the overall performance indicators of the structure meet the specifications and standards.

[0121] In general, the high-precision assembly method of the large-span steel corridor structure proposed in the present invention fully integrates advanced technical means such as digital modeling, precision measurement, and intelligent control, and realizes precise control of the entire process of structural installation. Compared with the existing technology, it not only greatly improves the overall installation accuracy of the structure, but also enhances the connection reliability and overall stability, and solves the problem of large cumulative errors that are inevitably caused by the current common use of manual measurement and mechanical limit for positioning and connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0122] Figure 1 A flow chart of the method provided by the present invention;

[0123] Figure 2Schematic diagram of the connection of two components in the embodiment. DETAILED DESCRIPTION

[0124] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0125] like Figure 1 As shown, it is a flow chart of a high-precision assembly method of a large-span steel corridor structure provided by the present invention, and the method comprises the following steps:

[0126] S10. Use the building information model to digitally model the large-span steel corridor structure, construct a three-dimensional spatial coordinate system, locate the positions of various components of the large-span steel corridor structure in the three-dimensional spatial coordinate system, and form an axis control network and a corner point control network;

[0127] S20, arranging the initial positions of the steel components at the pre-assembly site according to the three-dimensional spatial coordinate system, using a laser locator to initially calibrate the steel components, and comparing the positions of the steel components with the axis control network and the corner point control network in the three-dimensional spatial coordinate system;

[0128] S30, importing the building information model of the large-span steel corridor structure into the finite element analysis software, and performing preliminary structural verification on the large-span steel corridor structure;

[0129] S40. Multi-level torque sensors are installed at the bolt connection positions of the large-span steel corridor structure. According to the strength and nominal diameter of the bolts, the initial tightening torque value, half tightening torque value and final tightening torque value of the bolts are calculated using the restraining torque equation;

[0130] S50. When installing a single steel beam component, tighten the bolts to the initial tightening torque value, and re-measure and check the corner control network after completing the installation of each beam in the single-axis direction;

[0131] S60. After the installation of each layer of steel beam components is completed, the axis control network is used for re-measurement and verification, and the pre-tightening force of all connecting bolts of this layer is increased to the half-tightening torque value;

[0132] S70, install the last layer of steel beam chord and supporting structure, use laser positioning device to carry out positioning scanning, and verify the spatial position in the three-dimensional coordinate system;

[0133] S80. After the spatial position meets the design error standard, the preload force of all bolts in the large-span steel corridor structure shall be increased to the final tightening torque value;

[0134] S90. Use finite element analysis software to perform final structural verification on the installed large-span steel corridor structure, review the overall stability and stress distribution of the structure, and after confirming that all indicators meet the design requirements, conduct final acceptance to complete the entire assembly process.

[0135] The specific implementation methods of the above steps are described in detail below:

[0136] The specific implementation method of step S10 is to use the building information model to digitally model the large-span steel corridor structure and construct a spatial three-dimensional coordinate system. First, obtain the design drawings of the large-span steel corridor structure, and extract the geometric dimension information, material information and node connection information. Then use the building information modeling software to build a three-dimensional model, and mark the component number, installation sequence and connection method in the model. Next, a spatial three-dimensional coordinate system is established on the basis of the three-dimensional model, and its origin is set at the reference point of the structure. An axis control network is established in the coordinate system, and the main control point is set at the key node position. At the same time, a corner point control network is also established, and the control points are set at the four corners of each component. In this way, a complete digital model and a three-dimensional coordinate system are constructed. The main purpose of this step is to provide a reference reference for subsequent precise positioning.

[0137] The specific implementation method of step S20 is to arrange the initial positions of each steel component according to the spatial three-dimensional coordinate system at the pre-assembly site, and calibrate the component position using a laser locator. First, set up multiple reference points on site, and use a total station to measure and determine their spatial coordinates. Divide the pre-assembly area according to these reference points, and mark the component storage position and lifting channel. Then install the laser locator on the reference point, and use the rear intersection method to determine the instrument coordinates. Then use the locator to perform a three-dimensional scan of each component to obtain the actual spatial coordinates. Finally, compare and analyze the actual coordinates obtained by the scan with the established axis control network and corner point control network to generate deviation data. The purpose of this step is to check the deviation between the actual position and the designed position of each component, and provide a basis for subsequent precise positioning and installation.

[0138] The specific implementation method of step S30 is to convert the building information model into a finite element analysis model and perform preliminary structural verification on the large-span steel corridor structure. First, determine the unit type and mesh division density, and convert the model into a finite element analysis format. Then enter the boundary conditions, including support constraints and node connection methods. Next, apply a load combination, including dead load, live load, wind load and temperature load. Subsequently, a linear static analysis method is used to calculate the stress distribution and deformation. Finally, the calculation results are verified according to the specification requirements to ensure that the strength, stiffness and stability meet the design requirements. The purpose of this step is to evaluate the structural stress conditions and provide a basis for subsequent optimization design.

[0139] The specific implementation method of step S40 is to set a multi-stage torque sensor at the bolt connection position, and calculate the initial tightening torque value, half-tightening torque value and final tightening torque value according to the bolt strength and diameter. First, install a magnetic torque sensor at the connection position and connect it to the data acquisition system. Then determine the tensile strength according to the material grade of the bolt, and calculate the force area according to the nominal diameter of the bolt. Next, substitute the tensile strength, force area and friction coefficient into the confinement torque equation, and calculate the torque value of each stage. Among them, the initial tightening torque value is 35kN·m, the half-tightening torque value is 1215kN·m, and the final tightening torque value is 20~25kN·m. The purpose of this step is to adopt a multi-stage torque control strategy to ensure connection reliability.

[0140] The specific implementation method of step S50 is to tighten the bolts to the initial tightening torque value when installing a single steel beam component, and use a laser locator to re-measure the corner control network. First, check the correspondence between the connecting plate and the bolt hole to ensure that they are correctly matched. Then use a temporary fixing device to position the single component at the designed position. Then install the bolts and tighten them to the initial tightening torque value with a torque wrench. Then use a torque sensor to detect the actual torque value to ensure that the error between it and the design value is within the allowable range. After completing the installation of each frame in the single-axis direction, use a laser locator to measure the spatial coordinates of the corner control network and compare them with the design coordinates to ensure that the installation accuracy meets the requirements. The main purpose of this step is to ensure the accuracy of the installation of a single component.

[0141] The specific implementation method of step S60 is to use the axis control network to re-measure after the installation of each layer of steel beam components is completed, and increase the pre-tightening force of the connecting bolts to the half-tightening torque value. First, a laser locator is used to measure the spatial position of each layer of components after installation, and the measurement data is imported into the computer and automatically compared with the axis control network. According to the deviation distribution cloud map, overall adjustment is made to eliminate systematic errors. After the adjustment is completed, a torque wrench is used to increase the pre-tightening force of all connecting bolts of this layer to the half-tightening torque value, and it is checked with a torque sensor. This step is intended to ensure that the installation of each layer of components meets the accuracy requirements and lay the foundation for subsequent final tightening.

[0142] The specific implementation method of step S70 is to use a laser locator to perform three-dimensional scanning when installing the last layer of steel beam chords and supporting structures, and analyze their spatial positions in a three-dimensional coordinate system. First, adjust the last layer of steel beam chords to ensure that they match the lower structure. Then install the supporting structure to ensure that it is tightly connected to the main structure. Next, use a laser locator to perform three-dimensional scanning of the entire structure, and perform noise reduction and registration processing on the scanned point cloud data. Finally, convert the processed point cloud data into a three-dimensional model, and analyze its spatial position in a three-dimensional coordinate system. The purpose of this step is to verify whether the spatial position of the final structure meets the design requirements.

[0143] The specific implementation method of step S80 is to compare the measured spatial position with the design error standard, and compile a bolt final tightening torque construction plan based on the deviation, and finally perform bolt final tightening in different areas. First, compare the spatial position analysis results with the design error standard to determine whether the requirements are met. If they are met, compile a bolt final tightening torque construction plan and determine the tightening sequence. Then, perform bolt final tightening in different areas according to the construction plan, and use a torque wrench to increase the preload force to the final tightening torque value. Then use a torque sensor to review the final tightening torque value to ensure that it is correct. Finally, record and archive the final tightening torque detection data of each bolt. The purpose of this step is to ensure the installation accuracy and connection reliability of the overall structure.

[0144] The specific implementation method of step S90 is to use three-dimensional scanning to obtain the actual geometric model of the large-span steel corridor structure, and perform structural stability verification based on the model. First, the actual geometric model of the structure is obtained by three-dimensional scanning, compared with the original finite element analysis model, and the geometric parameters are updated. Then, the dead load and the design live load are reapplied, and the structural calculation is performed using a nonlinear analysis method. Next, the stress distribution, deformation and natural frequency are analyzed to evaluate the overall performance of the structure. Finally, after confirming that all indicators meet the design requirements, the completion acceptance and data archiving are carried out to complete the entire assembly process.

[0145] Specifically, the principle of the present invention is to establish a complete three-dimensional digital control system and adopt a multi-level torque control strategy to ensure the installation accuracy and reliability of each connection node.

[0146] First, the entire structure is 3D digitally modeled through the building information model, and a spatial 3D coordinate system is constructed on this basis. An axis control network and a corner point control network are set up in the coordinate system to strictly locate the spatial position of each component in the coordinate system. This provides a reference for subsequent precise positioning and installation.

[0147] Secondly, a laser locator is arranged in the pre-assembly area on site and its instrument coordinates are determined. Then, each component is scanned in three dimensions to obtain its actual spatial coordinates. By comparing and analyzing the coordinate data obtained by the scan with the control network, the installation deviation of each component can be grasped in real time. At the same time, these deviation data also provide a basis for subsequent error correction.

[0148] Secondly, install the torque sensor at the bolt connection position, and calculate the reasonable initial tightening, half tightening and final tightening torque values ​​according to the bolt strength characteristics. During the installation process, first tighten the bolts to the initial tightening torque. After completing the installation of each frame in the uniaxial direction, use the laser positioning diagonal point control network to re-measure to ensure local accuracy. Then, after each layer of components is installed, use the axis control network to check the overall deviation, and increase the pre-tightening force of the connecting bolts to the half-tightening torque value. Finally, after the installation is completed, it is uniformly increased to the final tightening torque value to ensure the connection reliability of the overall structure.

[0149] Finally, the actual geometric model is obtained by 3D scanning, compared with the original finite element analysis model, and the structural stability is re-checked. By considering factors such as geometric nonlinear effects and initial defects, the stress distribution, deformation, and natural frequency of the structure are evaluated to ensure that all performance indicators meet the design requirements.

[0150] The following is an example of a specific application scenario of the present invention: A new gymnasium project in a certain city uses a large-span steel corridor structure with a span of 150 meters and a total weight of about 20,000 tons. In order to ensure the installation accuracy and connection reliability of the overall structure, the project adopts the high-precision assembly method of the large-span steel corridor structure proposed by the present invention. The following is the specific implementation of the project:

[0151] First, the construction company invited a professional building information modeling team to conduct 3D digital modeling of the entire steel structure project. They first collected detailed design drawings and extracted the geometric dimensions, material properties and node connection information of each structural component. Then they used BIM software such as Revit to build a complete 3D solid model and marked the number, installation order and connection method of each component in the model.

[0152] Next, they established a unified three-dimensional spatial coordinate system based on the three-dimensional model. The origin of the coordinate system was set at the reference point of the main structure of the gymnasium, and the axis control network and corner point control network were established in the coordinate system. Among them, the main control points of the axis control network were set at the key node positions of the structure, such as the intersection of beams and columns, supports, etc. The control points of the corner point control network were arranged at the four corners of each component. In this way, the spatial position of the entire steel structure was strictly located in the three-dimensional coordinate system.

[0153] In the pre-assembly site, the engineering team first used a total station to measure and determine the spatial coordinates of multiple reference points. Based on these reference points, they divided the specific areas for steel component storage and hoisting operations. Then, a Leica NovaMS60 multi-function scanner was installed on one of the reference points, and the position of the instrument in the coordinate system was determined using the back intersection method. Subsequently, they used the scanner to perform a three-dimensional scan of all steel components in the pre-assembly area and obtained the actual spatial coordinates of each component.

[0154] The scanned data was imported into the computer system and compared with the previously established axis control network and corner control network. The results showed that the actual position of most components had a deviation of 0.5-3 cm from the designed position, and the deviation of some components even reached more than 5 cm. For this reason, they compiled a detailed deviation distribution report, which provided a basis for subsequent precise positioning and adjustment.

[0155] After a preliminary analysis of the installation deviation, the engineering team immediately started the finite element analysis. They converted the BIM model into an analysis model of the Midas Gen finite element software and carefully input its parameters. First, the unit type and mesh division were determined, and then the support constraints and node connection methods were entered. Next, they applied various working conditions including dead load, live load, wind load and temperature load, and used the linear static analysis method to calculate the stress distribution and deformation of the overall structure.

[0156] According to the analysis results, the engineering team found that some local components of the structure had certain stress concentration and deflection problems. To this end, they optimized the model locally and adjusted the size and connection method of some components. After recalculation, all performance indicators met the requirements of the specification. This laid a good foundation for the subsequent precise installation.

[0157] At the same time, the engineering team installed multiple magnetic torque sensors at the connection nodes and connected them to the data acquisition system. Based on experience, they determined that the tensile strength of the bolts was 900MPa and the nominal diameter was M24. Substituting into the locking torque equation, the calculation was:

[0158]

[0159] in:

[0160] M t =22.5kN·m (final tightening torque value)

[0161] F p =234kN (axial preload)

[0162] P = 3mm (thread pitch)

[0163] μ1=0.15(friction coefficient of thread contact surface)

[0164] μ2=0.12(friction coefficient of nut bearing surface)

[0165] d2=21.376mm(thread middle diameter)

[0166] D n =45mm (equivalent friction diameter of nut bearing surface)

[0167] α=30°(thread half angle)

[0168] η=0.12(torque loss coefficient)

[0169] Through calculation, they determined that the initial tightening torque value of the project was 5kN·m, the half-tightening torque value was 15kN·m, and the final tightening torque value was 22.5kN·m.

[0170] During the actual installation process, the engineering team first checked the matching of the connection plates and bolt holes of each component. After confirming that they were correct, a temporary fixing device was used to place the single steel beam component in the designed position. Then a torque wrench was used to tighten the connection bolts to an initial tightening torque value of 5kN·m. After tightening, they immediately used a torque sensor to detect the actual torque value and found that the deviation from the design value was within the allowable range. Figure 2 As shown, an example is given which includes a first component and a second component, wherein the two components are connected by a connecting plate, and the connecting plate has a plurality of bolt holes. Figure 2 The two red arrows in the figure indicate that the two connectors would separate to the sides if there were no connecting plate.

[0171] After completing the installation of each frame in the single-axis direction, the engineering party immediately used a laser scanner to re-measure the spatial coordinates of the corner point control network. By comparing with the design coordinates, it was found that the average spatial position error of each control point was within ±2cm, meeting the accuracy requirement of ±5cm.

[0172] After the installation of the first layer of steel beam components was completed, the engineering team switched to the overall deviation inspection mode using the axis control network. First, the spatial position of the components of this layer was measured using a laser scanner, and the data was imported into the computer system. Through automated comparison, it was found that the control points had deviations ranging from 0.5 to 3 cm. To this end, they compiled a detailed deviation distribution cloud map and made overall adjustments based on the cloud map to eliminate obvious systematic errors. After the adjustment was completed, the preload force of all connecting bolts of this layer was increased to a semi-tight torque value of 15kN·m using a torque wrench, and the torque sensor was used for verification.

[0173] When installing the last layer of steel beam chords and supporting components, the engineering team paid special attention to the matching with the lower structure. After multiple adjustments and trial assembly, they ensured that the upper and lower components could be connected together seamlessly. At this time, they once again used the Leica Nova MS60 scanner to perform a 3D scan of the entire structure. After data processing, a high-precision measured 3D model was generated.

[0174] The measured model was converted into the same three-dimensional coordinate system as the design model, and the engineering team compared and analyzed the spatial positions of the two. The results show that the linear error of the overall structure is controlled within ±1.5cm, and the angular error is within ±0.5°, meeting the design accuracy requirements of ±3cm and ±1°. According to calculations, the comprehensive position error E=52cm, which is less than the allowable value of 60cm.

[0175] In the final step, the engineering team prepared a construction plan for bolt final tightening based on the deviation. They first increased the preload of all bolts to a final tightening torque value of 22.5 kN·m and used a torque sensor to verify it. The entire process was carried out in an orderly manner in different areas, and the final tightening torque value of each bolt was recorded and archived.

[0176] After completing the final tightening of all bolts, the engineering team once again used 3D scanning technology to obtain the actual geometric model of the overall structure. It was imported into the Midas Gen software and compared and updated with the original finite element analysis model. On this basis, they re-applied the measured dead load and design live load, and calculated the structure using nonlinear analysis methods. The analysis results showed that the stress level, deformation, and natural frequency of each component met the requirements of the specification.

[0177] It should be noted that the explanations of the variables involved in the present invention are shown in Table 1 below.

[0178] Table 1 Variable explanation table

[0179]

[0180]

[0181] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A high-precision assembly method for a large-span steel corridor structure, characterized in that: The following steps are involved: S10, digitally modeling the large-span steel corridor structure using a building information model, constructing a spatial three-dimensional coordinate system, positioning each component of the large-span steel corridor structure in the spatial three-dimensional coordinate system, and forming an axis control network and a corner point control network; S20, arranging the initial positions of the steel components at the pre-assembly site according to the three-dimensional spatial coordinate system, using a laser locator to initially calibrate the steel components, and comparing the positions of the steel components with the axis control network and the corner point control network in the three-dimensional spatial coordinate system; S30, importing the building information model of the large-span steel corridor structure into finite element analysis software, and performing preliminary structural verification on the large-span steel corridor structure; S40, installing a multi-stage torque sensor at the bolt connection position of the large-span steel corridor structure, and calculating the initial tightening torque value, half tightening torque value and final tightening torque value of the bolt by using a restraining torque equation according to the strength and nominal diameter of the bolt; S50, when installing a single steel beam component, tighten the bolts to the initial tightening torque value, and re-measure and check the corner point control network after completing the installation of each beam in the uniaxial direction; S60, after completing the installation of the steel beam components of each layer, re-measure and check using the axis control network, and increase the pre-tightening force of all the connecting bolts of this layer to the semi-tightening torque value; S70, installing the last layer of steel beam chords and supporting structures, using the laser positioning device to perform positioning scanning, and verifying the spatial position in the three-dimensional spatial coordinate system; S80, after the spatial position meets the design error standard, the pre-tightening force of all bolts in the large-span steel corridor structure is increased to the final tightening torque value; S90. Use the finite element analysis software to perform final structural verification on the installed large-span steel corridor structure, review the overall stability and stress distribution of the structure, and after confirming that all indicators meet the design requirements, conduct final acceptance to complete the entire assembly process.

2. The method according to claim 1, characterized in that The step S10 specifically includes: Step 101, obtaining the design drawings of the large-span steel corridor structure, and extracting the geometric size information, material information and node connection information of the large-span steel corridor structure; Step 102: Use building information modeling software to create a three-dimensional model of the long-span steel corridor structure, and mark the component numbers, installation sequence and connection methods in the three-dimensional model; Step 103, establishing the spatial three-dimensional coordinate system based on the three-dimensional model, and setting the origin of the spatial three-dimensional coordinate system at the reference point of the large-span steel corridor structure; Step 104, establishing the axis control network in the three-dimensional spatial coordinate system, and setting the main control points of the axis control network at the key node positions of the large-span steel corridor structure; Step 105: Establish the corner point control network in the three-dimensional spatial coordinate system, and set the control points of the corner point control network at the four corners of each component of the long-span steel corridor structure.

3. The method according to claim 1, characterized in that The step S20 specifically includes: Step 201: setting a plurality of reference points at the pre-assembly site according to the spatial three-dimensional coordinate system, and determining the spatial coordinates of the reference points by measuring with a total station; Step 202, dividing the pre-assembly area according to the reference point, and marking the component storage position and the lifting channel in the pre-assembly area; Step 203, installing the laser locator at the reference point, and determining the instrument coordinates of the laser locator using the resection method; Step 204: Use the laser positioning device to perform three-dimensional scanning on each steel component to obtain the actual spatial coordinates of each steel component; Step 205: Compare and analyze the actual space coordinates with the axis control network and the corner point control network to generate deviation data.

4. The method according to claim 1, characterized in that The step S30 specifically includes: Step 301: convert the building information model into a finite element analysis model, and determine the unit type and mesh division density; Step 302: input the boundary conditions of the large-span steel corridor structure, including support constraint conditions and node connection methods; Step 303, applying a load combination, including a dead load, a live load, a wind load and a temperature load; Step 304: Calculate the stress distribution and deformation of the large-span steel corridor structure using a linear static analysis method; Step 305: Verify the calculation results according to the specification requirements to ensure that the strength, stiffness and stability meet the design requirements.

5. The method according to claim 1, characterized in that The step S40 specifically includes: Step 401, installing a magnetic torque sensor at the bolt connection position, and connecting the torque sensor to a data acquisition system; Step 402: Determine the tensile strength of the bolt according to its material grade, and calculate the stress-bearing area of ​​the bolt according to its nominal diameter; Step 403: Substitute the tensile strength, the force-bearing area and the friction coefficient into the restraining moment equation; Step 404: Calculate the initial tightening torque value, the half tightening torque value and the final tightening torque value through the locking torque equation.

6. The method according to claim 1, characterized in that The step S50 specifically includes: Step 501, before installing a single steel beam component, check the correspondence between the connecting plate and the bolt hole; Step 502: using a temporary fixing device to position the single steel beam component at a designed position; Step 503, installing the bolts and tightening the bolts to the initial tightening torque value using a torque wrench; Step 504: using the torque sensor to detect the actual torque value of the bolt to ensure that the error between the actual torque value and the initial tightening torque value is within an allowable range; Step 505: After completing the installation of each frame in the single-axis direction, use the laser locator to measure the spatial coordinates of the corner point control network; Step 506: Compare the measured coordinates with the designed coordinates to ensure that the installation accuracy meets the requirements.

7. The method according to claim 1, characterized in that The step S60 specifically includes: Step 601, using the laser positioning device to measure the spatial position of each layer of steel beam components after installation; Step 602, importing the measurement data into a computer and automatically comparing it with the axis control network; Step 603, calculating the spatial coordinate deviation of each control point and generating a deviation distribution cloud map; Step 604: perform overall adjustment according to the deviation distribution cloud map to eliminate systematic errors; Step 605: After the adjustment is completed, the pre-tightening force of all the connecting bolts of the layer is increased to the semi-tightening torque value using a torque wrench; Step 606: Use the torque sensor to review and confirm the semi-tightening torque value.

8. The method according to claim 1, characterized in that The step S70 specifically includes: Step 701, install the last layer of steel beam chords, and adjust their spatial position until they match the lower structure; Step 702: Install the support structure to ensure that it is tightly connected to the main structure; Step 703: Use the laser positioning device to perform three-dimensional scanning on the entire structure; Step 704: performing noise reduction and registration processing on the scanned point cloud data; Step 705: convert the processed point cloud data into a three-dimensional model; Step 706: Perform spatial position analysis on the three-dimensional model in the spatial three-dimensional coordinate system.

9. The method according to claim 1, characterized in that: The step S80 specifically includes: Step 801, comparing the spatial position analysis result with the design error standard; Step 802, prepare a bolt final tightening torque construction plan and determine the bolt tightening sequence; Step 803, final tightening of bolts in different areas according to the construction plan; Step 804: using a torque wrench to increase the bolt pre-tightening force to the final tightening torque value; Step 805: using the torque sensor to check the final tightening torque value; Step 806: Record and archive the final tightening torque detection data of each bolt.

10. The method according to claim 1, characterized in that The step S90 specifically includes: Step 901: Acquire the actual geometric model of the large-span steel corridor structure by three-dimensional scanning; Step 902: Compare the actual geometric model with the original finite element analysis model and update geometric parameters; Step 903, reapplying the load combination, including the measured dead load and the designed live load; Step 904: Perform structural calculation using a nonlinear analysis method; Step 905: Analyze stress distribution, deformation and natural frequency to evaluate the overall performance of the structure; Step 906: After confirming that all indicators meet the design requirements, final acceptance and data archiving are carried out to complete the entire assembly process.

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