Special-shaped curved steel-concrete composite tower segment and its manufacturing process

Abstract

The present invention relates to a steel-concrete composite tower segment with a special-shaped curved structure and a manufacturing process. The cross-section of the steel-concrete composite tower is a special-shaped curved cross-section, which is composed of R1m and R3m circular arc curves and transition straight lines. The tower height direction is a variable cross-section and changes in a curve. The tower column segment is composed of a box inner wall panel, a curved outer wall panel, a compartment panel, a box inner connector, and horizontal and vertical steel bars. Advantages: First, it realizes the lofting of complex curved structures; second, it successfully realizes the assembly precision control of the special-shaped curved steel-concrete composite tower segment by adopting plate unit segmentation, special tooling constraints, reference network monitoring, and reasonable assembly sequence, thereby improving the processing and manufacturing technology level of the steel-concrete composite tower; third, it realizes the control of welding deformation of the steel-concrete composite tower segment, which is a breakthrough in the linear control technology of complex special-shaped curved structures; fourth, it adopts different detection methods such as process monitoring, finished product detection, and physical pre-assembly inspection to realize quality precision control of the construction process, thereby ensuring the quality of the final product of the project.

Description

Technical Field

[0001] The invention relates to a special-shaped curved steel-concrete composite tower segment and a manufacturing process thereof, which can realize a variable cross-section in the tower height direction and a curved change, and belongs to the field of super-large steel-concrete bridge manufacturing. Background Art

[0002] The domestic application of steel-concrete composite tower technology began with the Fifth Nanjing Yangtze River Bridge, pioneering a new structural system for this type of bridge tower. The steel-concrete composite tower offers a flexible structural design that can adapt to unique structural shapes. The steel shell serves as the formwork for pouring concrete, reducing the amount of formwork required for concrete-concrete composite towers. It also reduces the steel consumption of pure steel-concrete composite towers, resulting in a cost somewhere between concrete and steel-concrete composite towers. The advantages of both steel and concrete contribute to structural durability. However, the resulting steel-concrete composite tower segments cannot achieve irregular cross-sections or vertical curves, failing to meet the requirements for a curvilinear, variable cross-section along the tower's height. Because the tower height direction has a variable cross-section and changes in a curve, the manufacturing has the following technical difficulties: ⑴ The segment line shape is complex, and the segment line shape manufacturing and precision control are difficult; ⑵ The structure consists of many parts, which are mainly special-shaped, and it is difficult to assemble the segment structure and control the dimensional accuracy; ⑶ The main structure of the segment is mainly medium-thick plates (16mm to 24mm), and there are many structural connection welds, and the welding deformation has a great impact on the structure; ⑷ The segment structure is large in volume and complex in line shape, and its assembly inspection and finished product precision control are difficult. Summary of the Invention

[0003] Design purpose: To design a special-shaped curved steel-concrete composite tower segment and manufacturing process that can achieve a variable cross-section in the tower height direction and a curved shape.

[0004] Design scheme: In order to achieve the above design objectives, the present invention adopts the following technical solutions in the design scheme:

[0005] 1. Technical solution for construction control of segment alignment: Loft complex curved parts through digital models, adopt equipment and tooling to ensure the curve alignment of parts, make curved plate units on special tooling, make assembly tooling according to the segment alignment and assemble the segments, and control the alignment of parts, plate units, and segments in stages to ensure that the overall segment alignment meets the design requirements.

[0006] 2. Technical solution for segment assembly precision control: Use digital models to lay out parts and add process allowances. Utilize high-precision CNC flame cutting equipment for cutting materials. Strictly control the accuracy of plate unit welding. Use a measuring grid to accurately position each part on a dedicated tooling. Allow 2 to 4 mm for welding shrinkage in the cross-sectional dimensions.

[0007] 3. Technical solution for controlling segment welding deformation: Determine the welding groove form and welding process through experiments based on the thickness of the segment components and the form of the joints; specify the welding sequence and welding principles for each weld based on the structural characteristics of the segment; use temporary supports and reinforcement before welding for areas with large welding volumes and weak structural rigidity; and perform corrections on post-weld deformation.

[0008] 4. Technical solution for segment manufacturing accuracy testing: During the segment assembly process, the segments are monitored using a measurement reference network and elevation control points independent of the tooling. Finished segments are inspected using laser 3D scanning measurement equipment to comprehensively determine segment accuracy deviations. The connection relationship between segments is tested for interface matching accuracy through vertical physical pre-assembly.

[0009] Structural solution: Based on the structural characteristics of the special-shaped curved steel-concrete composite tower segment, combined with the steel structure manufacturing process and construction technology, and considering the characteristics of the steel-concrete composite tower segment, such as the large number of components, dense welds and easy deformation, the steel-concrete composite tower segment is divided into several plate units for manufacturing, and then welded together into an integral segment. The key process solution for manufacturing this type of segment is as follows:

[0010] ⑴ Parts processing plan: Flat parts can be processed according to the previous steel bridge construction technology; for curved parts, the accuracy and linearity of curved parts can be guaranteed through digital modeling and lofting, intelligent CNC cutting and marking, and mechanized processing.

[0011] (2) Plate unit fabrication plan: The fabrication technology for planar plate units is mature and has been applied in the Nanjing Yangtze River Fifth Bridge project. For the fabrication of curved plate units, different types of assembly tooling are required to be designed and manufactured based on the linear characteristics of each plate unit to ensure the linear control requirements of the plate unit fabrication. On the dedicated tooling, the plate units are assembled, welded, and deformed, and finally the horizontal and vertical reinforcements are assembled.

[0012] ⑶ Segment assembly plan: Based on the structural characteristics of the segments, the plan is simulated through the BIM digital model to formulate a reasonable segment assembly sequence; based on the segment size and line shape, special assembly tooling is designed, and the component units are assembled under the constraints of the tooling; during the assembly process of each component unit, a total station and a level are used for on-site monitoring to ensure the accurate assembly of each part.

[0013] (4) Segmental welding plan: According to the structural weld design requirements, the groove form and welding process of each joint are determined through process tests; in order to reduce the amount of welding deformation, temporary process partitions and supports are used for rigid reinforcement; in order to avoid abnormal deformation, according to the characteristics of structural symmetry, the segmental structural welds adopt the symmetrical welding principle; for the sake of construction operability, the step-by-step method is adopted for structural welding.

[0014] ⑸ Attached steel bar connection and accessory installation: After the segment welding is completed, connect the transverse steel bar joints between each plate unit, install the tie steel bars in the box, and install the platform, ladder and other accessory structures in the segment.

[0015] (6) Inspection plan for finished segment products: After the segment welding is completed, the local deformation of the structure is subjected to thermal correction treatment, and the entire segment is subjected to precision inspection using laser three-dimensional scanning measurement equipment.

[0016] ⑺ Segment pre-assembly: Based on the structural characteristics of the steel-concrete composite tower segment, vertical entity pre-assembly is adopted to simulate the bridge installation state and conduct interface matching accuracy inspection.

[0017] Working principle: According to the key process plan for manufacturing steel-concrete composite tower segments, the key points and principles of each process are as follows:

[0018] ⑴ Key points of curved parts processing technology: Based on the design structure and line shape, the digital model is used to lay out the curved parts; combined with the structural processing technology, process allowances are added to the curved parts; the sheet metal unfolding function of the 3D software is used to obtain the 2D contour of the curved parts; the compilation software is used to generate program files, and CNC cutting equipment is used for cutting and laser automatic marking to arrange the reference line; mechanical equipment is used to perform peripheral processing of parts and open grooves, etc.; cold pressing equipment and thermal correction measures are used to perform curved forming of parts.

[0019] ⑵ Key points of the curved plate unit manufacturing process: The curved outer wall plate unit is manufactured using curved tooling, and the tooling is designed to be adjustable and movable, which is convenient for adapting to changes in structural dimensions. After the curved outer wall panel is formed on the special tooling, it is fixed to the tooling with rigid fasteners, and the plate ribs are tightly assembled with the curved outer wall panel. The plate unit is welded using a CO2 gas shielded welding process with low line energy, and the welding sequence, symmetrical welding, welding parameters, etc. are strictly controlled to reduce deformation. After welding is completed, the rigid fasteners are released for plate unit inspection, and local deformation is corrected using a thermal correction process until the plate unit accuracy meets the standard requirements. Steel bars with processed end connection threads are inserted into the holes of the horizontal and vertical ribs of the plate unit in turn, and fixed with temporary tooling.

[0020] ⑶ Key points of segment assembly process: According to the structural characteristics of the segment, the assembly sequence of each plate unit is specified, and the assembly scheme is simulated through the BIM digital model. The assembly sequence is continuously optimized to ensure the smooth assembly of each unit; according to the segment size and line shape, special tooling is designed and manufactured, and the flatness deviation of the tooling bottom surface is less than 2mm. The inner and outer plate unit positioning devices are arranged, and the longitudinal and transverse measurement reference lines and elevation monitoring points are arranged outside the tooling; on the tooling, the parts are assembled from the inside to the outside based on the surrounding measurement network. The main structure assembly sequence is: inner wall plate unit → compartment plate unit → two-way curved plate unit → twisted plate unit → box internal connector, etc. After the assembly is qualified, temporary process partitions, horse plates, etc. are used to rigidly fasten the key parts.

[0021] ⑷ Key points of segment welding process: Based on the groove form, welding process and welding materials determined by the welding process test, automated welding equipment shall be used for welding in priority; rigid temporary consolidation parts such as process partitions and horse plates shall be added at the interface parts of the segments, the joints of the plate units, and the T-joints to improve the structure's ability to resist deformation and welding shrinkage, which is beneficial to the guarantee of structural dimensional accuracy; based on the structural characteristics of the segments and previous experience in welding steel-concrete composite towers, a strict welding sequence shall be stipulated in accordance with the principle of symmetrical welding to ensure that the stress of the structure is nearly evenly distributed during the welding process, thereby avoiding distortion of the segment as a whole; in order to reduce the internal stress of the structural welding and facilitate welding operations, the segments shall be welded in stages (first welding the welds of the inner compartment structure composed of the inner wall panels, and then welding the welds of the box structure composed of the partition panels and outer wall panels).

[0022] ⑸ Key points for connecting the steel bars attached to the wall panels and installing the accessories: After the segment welding is completed, first use the sleeve machine to connect the attached transverse steel bars on the wall panels, then assemble the transverse steel bar anchorage ends, and finally assemble the tie bars in the box; in the elevator shaft warehouse, weld the elevator pre-welded parts and the docking station platform; install inclined ladders, platforms and other structures in the pedestrian ladder passage.

[0023] ⑹ Key points of segment detection process: Utilize the local detection network and adopt a total station to monitor the baseline of the segment plate unit, and adopt a level to monitor the horizontal baseline of the plate unit and the segment top elevation to ensure that the assembly accuracy is controllable. Due to the large overall volume and complex linear shape of the segment, a laser three-dimensional scanning measurement equipment is introduced to perform an overall scan of the exposed surface of the segment to obtain the actual manufacturing physical model, and the physical model is compared with the theoretical model using the least squares method to obtain a comprehensive deviation report of the segment.

[0024] ⑺ Key points of segment pre-assembly process: According to the cross-sectional structure and linear characteristics of the steel-concrete composite tower, vertical pre-assembly is suitable for segment entity pre-assembly; considering the construction safety and streamlined construction requirements, a model is adopted for pre-assembly; pre-assembly is carried out through baseline alignment and elevation control to ensure the matching accuracy requirements of the connection interface; set the bridge position alignment line at the interface, install the bridge position positioning guide device (designed according to the linear shape and characteristics of the steel-concrete composite tower), and check the interface and vertical steel bar alignment accuracy.

[0025] Technical Solution 1: A special-shaped curved structure steel-concrete composite tower segment. The cross-section of the steel-concrete composite tower is a special-shaped curved cross-section, consisting of R1m, R3m arc curves and transition straight lines. The cross-section in the tower height direction is variable and changes in a curve. The tower column segment is composed of box inner wall panels, curved outer wall panels, compartment panels, box inner connectors and horizontal and vertical steel bars.

[0026] Technical Solution 2: A manufacturing process for special-shaped curved steel-concrete composite tower segments.

[0027] (1) Curved part processing technology: Based on the design structure and linear shape, the digital model is used to lay out the curved parts; in combination with the structural processing technology, process allowances are added to the curved parts; the sheet metal unfolding function of the 3D software is used to obtain the 2D contour of the curved parts; the program files are generated using the compilation software, and the CNC cutting equipment is used for blanking and the laser automatic marking is used to arrange the reference line; mechanical equipment is used to process the parts around the parts and open the grooves; cold forming equipment and thermal correction measures are used to form the curves of the parts;

[0028] (2) Curved plate unit manufacturing process: The curved outer wall plate unit is manufactured using a curved tooling design that is adjustable and movable to accommodate changes in structural dimensions. After the curved outer wall plate is formed on the dedicated tooling, it is fixed to the tooling with a rigid fastener, and the plate ribs are tightly assembled with the curved outer wall plate. The plate unit is welded using a CO2 gas shielded welding process with low line energy, and the welding sequence, symmetrical welding, and welding parameters are strictly controlled to reduce deformation. After welding is completed, the rigid fasteners are removed for plate unit inspection, and local deformation is corrected using a thermal correction process until the plate unit accuracy meets standard requirements. Steel bars with pre-processed end connection threads are inserted into the holes in the horizontal and vertical ribs of the plate unit in sequence and fixed with temporary tooling.

[0029] ⑶ Segment assembly process: According to the structural characteristics of the segment, the assembly order of each plate unit is specified. The assembly scheme is simulated through the BIM digital model, and the assembly order is continuously optimized to ensure the smooth assembly of each unit. According to the segment size and linear shape, a special tool is designed and manufactured. The flatness deviation of the tool bottom is less than 2mm. The inner and outer plate unit positioning devices are arranged. The longitudinal and transverse measurement reference lines and elevation monitoring points are arranged outside the tool. On the tool, the components are assembled from the inside to the outside based on the surrounding measurement network. The main structural assembly order is: inner wall panel unit → compartment panel unit → bidirectional curved panel unit → twisted panel unit → box connector, etc. After the assembly is qualified, temporary process partitions and horse plates are used to rigidly fasten the key parts.

[0030] (4) Segment welding process: Based on the groove form, welding process, and welding materials determined by the welding process test, automated welding equipment is preferred for welding. Rigid temporary reinforcement components such as process baffles and horse plates are added at the interface parts of the segments, the joints between plate units, and the T-joints to improve the structure's ability to resist deformation and welding shrinkage, which is beneficial to ensuring the structural dimensional accuracy. Based on the structural characteristics of the segments and previous experience in welding steel-concrete composite towers, a strict welding sequence is specified in accordance with the principle of symmetrical welding to ensure that the stress of the structure is nearly evenly distributed during the welding process and to avoid distortion of the entire segment. To reduce internal stress in the structural welding and facilitate welding operations, the segments are welded using a staged method (first welding the welds of the inner compartment structure composed of the inner wall panels, and then welding the welds of the box structure composed of the sub-compartment panels and outer wall panels).

[0031] ⑸ Connection of steel bars attached to the wall panels and installation of accessories: After the segment welding is completed, first use a sleeve to mechanically connect the attached transverse steel bars on the wall panels, then assemble the transverse steel bar anchorage ends, and finally assemble the tie bars in the box; in the elevator shaft, weld the elevator pre-welded parts and the docking station platform; install inclined ladders, platforms and other structures in the pedestrian ladder passage;

[0032] (6) Segment detection process: Using the local detection network, a total station is used to monitor the baseline of the segment plate unit, and a level is used to monitor the horizontal baseline of the plate unit and the segment top elevation to ensure that the assembly accuracy is controllable. Due to the large overall volume and complex linear shape of the segment, a laser 3D scanning measurement device is introduced to scan the exposed surface of the segment as a whole to obtain the actual manufacturing physical model. The physical model is then compared with the theoretical model using the least squares method to obtain a comprehensive deviation report of the segment.

[0033] ⑺ Segment pre-assembly process: According to the cross-sectional structure and linear characteristics of the steel-concrete composite tower, vertical pre-assembly is suitable for segment entity pre-assembly operations; considering the construction safety and streamlined construction requirements, a model is adopted for pre-assembly; pre-assembly is carried out through baseline alignment and elevation control to ensure the matching accuracy requirements of the connection interface; set the bridge position alignment line at the interface, install the bridge position positioning guide device (designed according to the linear shape and characteristics of the steel-concrete composite tower), and check the interface and vertical steel bar alignment accuracy.

[0034] Compared with the background technology, the present invention has the following advantages: first, it realizes the lofting of complex curved structures by combining BIM modeling technology with parts processing, plate unit production, and segment assembly technology, and can be used for technical guidance of construction at each stage, which is beneficial to quality and precision control; second, it successfully realizes the precision control of segment assembly of special-shaped curved steel-concrete composite towers by adopting plate unit segmentation, special tooling constraints, reference network monitoring, and reasonable assembly sequence, and improves the processing and manufacturing technology level of steel-concrete composite towers; third, it realizes the control of welding deformation of steel-concrete composite tower segments by determining appropriate welding technology, stipulating reasonable welding sequence, and adopting various rigid constraint mechanisms, which is a breakthrough in the linear control technology of complex special-shaped curved structures; fourth, it adopts different detection methods such as process monitoring, finished product detection, and entity pre-assembly inspection to realize quality and precision control of the construction process, and ensure the quality of the final product of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the steel-concrete composite tower segment of the bridge.

[0036] Figure 2 This is a schematic diagram of the facade of the manufacturing tooling for the special-shaped curved steel-concrete composite tower segment.

[0037] Figure 3 yes Figure 2 Floor plan diagram.

[0038] Figure 4 It is a schematic diagram of the vertical assembly sequence of special-shaped curved steel-concrete composite tower segments.

[0039] Figure 5 This is the vertical welding sequence diagram of the special-shaped curved steel-concrete composite tower segment.

[0040] Figure 6 This is a schematic diagram of the vertical pre-assembly of special-shaped curved steel-concrete composite tower segments. DETAILED DESCRIPTION

[0041] Example 1: Attached Figure 1-6A special-shaped curved steel-concrete composite tower segment. The cross-section of the steel-concrete composite tower is a special-shaped curved cross-section composed of R1m and R3m arc curves and transition lines. The cross-section changes in the tower height direction and is curved. The tower column segment consists of a box inner wall panel 1, a curved outer wall panel 4, a partition panel 5, a box inner connector 2, and horizontal and vertical steel bars 3. The box inner wall panel 1 is a flat plate unit. The curved outer wall panel 4 is a bidirectional curved plate unit and a twisted plate unit. The partition panel 5 is a flat plate unit.

[0042] The special-shaped curved steel-concrete composite tower segment structure is implemented according to the following process flow:

[0043] (1) Construction preparation: review the design drawings, optimize the structure and welding unreasonable parts; formulate the manufacturing plan of the steel-concrete composite tower segment and reasonably divide the manufacturing units; determine the manufacturing process and control measures of the steel-concrete composite tower segment; prepare the construction drawings and related documents of the steel-concrete composite tower segment.

[0044] (2) Tooling design and production: Based on the structural and linear characteristics of the steel-concrete composite tower segments, special assembly tooling suitable for shape and linear control is designed, and longitudinal and transverse benchmarks and elevation control points are established. The tooling accuracy must be higher than the segment manufacturing accuracy requirements.

[0045] (3) Segment assembly construction: First, complete the production of each plate unit that makes up the segment, especially the production accuracy of the curved dense rib plate must be strictly controlled to ensure that the size and line shape of each plate unit involved in the assembly meet the requirements; use the reference network on the special tooling to monitor the segment assembly, and put them in place in the prescribed order, and use temporary supports, rigid horse plates, etc. for temporary fixation to ensure construction safety and stable structural assembly dimensions; monitor the assembly process, adjust the assembly deviation in time, and add welding process reserves considering the shrinkage factor of later welding; welding operations can only be carried out after the assembly size, line shape, and process reserves are monitored and qualified.

[0046] (4) Segment welding construction: After the segment assembly is qualified, the segment welding operation shall be carried out according to the prescribed welding sequence and welding process; the segment assembly and welding shall be carried out in two stages: the first stage is to complete the assembly and welding of the inner wall panels of the box, and the second stage is to complete the assembly and welding of the outer wall panels and the inner structure of the box; after the welding is completed, the local deformation of the welding shall be detected and corrected.

[0047] (5) Segment detection and pre-assembly inspection: Use high-precision three-dimensional scanning measurement equipment to perform an overall scan of the outer wall panels around the steel-concrete composite tower segment. Data collection can be completed through 4 stations around the segment, and software is used for data processing. The collected data is compared with the theoretical model for deviation to form a deviation analysis report; according to the segment structure, pre-assembly tooling is set up to ensure that the tooling support is stable and the accuracy meets the requirements. The first segment is positioned on the tooling with the measurement reference. After passing the inspection, the first segment is positioned with the reference of the first segment, and the structural matching accuracy of the adjacent segments is inspected. Unqualified parts are corrected, and the positioning guide device and monitoring reference line for the bridge position are installed and laid out.

[0048] The manufacturing process of steel-concrete composite tower segments with special-shaped curved structures is suitable for the manufacturing of steel-concrete composite towers and steel tower segments with special-shaped curved vertical welding. This method can accurately control the structural dimensions of the segments through tooling, effectively ensure the accuracy of complex linear shapes through phased linear control measures, take welding process measures to ensure structural accuracy and weld quality, and use process inspection, finished product inspection, physical simulation inspection and other means to analyze structural accuracy deviations. During the implementation of the project, the quality of steel-concrete composite tower segments is guaranteed by continuously refining the process methods, improving the comprehensive quality of construction personnel, and strengthening the quality and accuracy control of the process.

[0049] The manufacturing process of steel-concrete composite tower segments with special-shaped curved structures is effective in controlling the manufacturing quality of steel-concrete composite tower segments. The process has strong feasibility and the method is mature and stable. It is a key technology for solving the problem of vertical manufacturing of steel-concrete composite towers and steel tower segments. It is also a new breakthrough in the manufacturing technology of steel-concrete composite towers for domestic bridges. It is worthy of reference for similar projects and has promotion value.

[0050] It should be understood that although the above embodiments provide a relatively detailed textual description of the design ideas of the present invention, these textual descriptions are only simple textual descriptions of the design ideas of the present invention, rather than limitations on the design ideas of the present invention. Any combination, addition or modification that does not exceed the design ideas of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A special-shaped curved steel-concrete composite tower segment, characterized by: The cross section of the steel-concrete composite tower is a special-shaped curved cross section, which is composed of R1m and R3m arc curves and transition straight lines. The cross section is variable in the tower height direction and changes in a curve. The tower column segment is composed of a box inner wall plate (1), a curved outer wall plate (4), a compartment plate (5), a box inner connector (2) and horizontal and vertical steel bars (3). The curved outer wall plate (4) is a bidirectional curved plate unit and a twisted plate unit. The manufacturing process is as follows: (1) Curved part processing technology: Based on the design structure and linear shape, the digital model is used to lay out the curved parts; in combination with the structural processing technology, process allowances are added to the curved parts; the sheet metal unfolding function of the 3D software is used to obtain the 2D contour of the curved parts; the program files are generated using the compilation software, and the CNC cutting equipment is used for blanking and the laser automatic marking is used to arrange the reference line; the mechanical equipment is used to process the parts around the parts and open the grooves; the cold forming equipment and thermal correction measures are used to form the curves of the parts; (2) Curved plate unit manufacturing process: The curved outer wall plate unit is manufactured using a curved fixture, which is designed to be adjustable and movable to accommodate changes in structural dimensions. After the curved outer wall plate is formed on the fixture, it is fixed to the fixture with a rigid fastener, and the plate ribs are tightly assembled with the curved outer wall plate. The plate unit is welded using a CO2 gas shielded welding process with low line energy, and the welding sequence, symmetrical welding, and welding parameters are strictly controlled to reduce deformation. After welding is completed, the rigid fastener is removed for plate unit inspection, and local deformation is corrected using a thermal correction process until the plate unit accuracy meets standard requirements. Steel bars with pre-processed end connection threads are inserted into the holes of the horizontal and vertical ribs of the plate unit in sequence and fixed with temporary fixtures. ⑶ Segment assembly process: According to the structural characteristics of the segment, the assembly order of each plate unit is specified. The assembly scheme is simulated through the BIM digital model, and the assembly order is continuously optimized to ensure the smooth assembly of each unit. According to the segment size and linear shape, a special tooling is designed and manufactured. The flatness deviation of the tooling bottom surface is less than 2mm. The inner and outer plate unit positioning devices are arranged. The longitudinal and transverse measurement reference lines and elevation monitoring points are arranged outside the tooling. On the tooling, the components are assembled from the inside to the outside based on the surrounding measurement network. The main structural assembly order is: inner wall panel unit → compartment panel unit → bidirectional curved panel unit → twisted panel unit → box connector. After the assembly is qualified, temporary process partitions and horse plates are used to rigidly fasten the key parts. (4) Segment welding process: Automated welding equipment is used for welding based on the groove form, welding process, and welding materials determined by welding process tests. Process baffles and temporary rigid reinforcements of horse plates are added to the interface parts of the segments, the joints between plate units, and the T-joints to improve the structure's ability to resist deformation and welding shrinkage, which is beneficial to ensuring the accuracy of the structural dimensions. Based on the structural characteristics of the segments and previous experience in welding steel-concrete composite towers, a strict welding sequence is specified in accordance with the principle of symmetrical welding to ensure that the stress of the structure is nearly evenly distributed during the welding process, avoiding distortion of the entire segment. To reduce internal stress in structural welding and facilitate welding operations, the segments are welded in stages, i.e., the welds of the inner compartment structure composed of the inner wall panels are welded first, followed by the welds of the box structure composed of the sub-compartment panels and outer wall panels. ⑸ Connection of steel bars attached to the wall panels and installation of accessories: After the segment welding is completed, first use a sleeve to mechanically connect the attached transverse steel bars on the wall panels, then assemble the transverse steel bar anchorage ends, and finally assemble the tie bars in the box; in the elevator shaft, weld the elevator pre-welded parts and the docking station platform; install the inclined ladder and platform structure in the pedestrian ladder passage; (6) Segment detection process: Using the local detection network, a total station is used to monitor the baseline of the segment plate unit, and a level is used to monitor the horizontal baseline of the plate unit and the segment top elevation to ensure that the assembly accuracy is controllable. Due to the large overall volume and complex linear shape of the segment, a laser 3D scanning measurement device is introduced to scan the exposed surface of the segment as a whole to obtain the actual manufacturing physical model. The physical model is then compared with the theoretical model using the least squares method to obtain a comprehensive deviation report of the segment. ⑺ Segment pre-assembly process: According to the cross-sectional structure and linear characteristics of the steel-concrete composite tower, vertical pre-assembly is suitable for segment entity pre-assembly operations; considering the construction safety and streamlined construction requirements, a model is adopted for pre-assembly; pre-assembly is carried out through baseline alignment and elevation control to ensure the matching accuracy requirements of the connection interface; bridge position alignment lines are set at the interfaces, and bridge position positioning guide devices are installed, that is, the interfaces and vertical reinforcement alignment accuracy are designed and checked according to the linear shape and characteristics of the steel-concrete composite tower.

2. The special-shaped curved steel-concrete composite tower segment according to claim 1 is characterized by: The inner wall panel (1) of the box is a flat panel unit.

3. The special-shaped curved steel-concrete composite tower segment according to claim 1 is characterized by: The compartment plate (5) is a flat plate unit.

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