Vertical type pre-assembly construction method for block type steel tower

Abstract

The invention discloses a block type steel tower vertical type pre-assembly construction method which comprises the steps that a pre-assembly base is designed, and the base is fixed to the ground; the section on the pre-assembled side is hoisted into a pre-assembled base, the base is provided with longitudinal and transverse datum lines, measurement is conducted after alignment, and the steel tower and the base are temporarily connected through a connecting base after the requirement is met; the section on the other pre-assembled side is hoisted into a pre-assembled base to be measured, and after the requirement is met, the steel tower and the base are temporarily connected through a connecting base; hoisting one side of the next section to be spliced, measuring, temporarily connecting the sections of the steel tower after the requirement is met, and completing the pre-splicing of the subsequent sections in the same process; and after all the sections are hoisted in, comprehensive detection is conducted on the steel tower sections, after design and specification requirements are met, temporary matching pieces are installed, and after inspection is qualified, the sections are moved out of a pre-splicing site one by one. The tool system is basically of a bolting structure and can be repeatedly used, welding-free construction reduces damage to the paint surface of a finished product, and high efficiency and environmental protection are achieved.

Description

Technical Field

[0001] The invention relates to a pre-assembly construction method, in particular to a vertical pre-assembly construction method for a segmented steel tower. Background Art

[0002] Traditional steel tower pre-assembly mostly adopts horizontal methods, which have the following defects: 1. Different from the bridge position state: it cannot simulate the bridge position installation state, and the annular seam matching is not accurate; 2. Force simulation distortion: horizontal pre-assembly cannot utilize the natural compression effect of the steel tower's own weight on the contact surface, and additional horizontal force needs to be applied. The operation is complicated and easy to cause linear deviation; 3. Poor site adaptability: it occupies a large space and has strict requirements on the flatness of the site, making it difficult to adapt to the pre-assembly requirements of ultra-high segments; 4. Stability risk: the traditional support system in vertical pre-assembly (such as cement floor + support bench) is insufficient in wind and impact resistance, and there is a risk of tipping over.

[0003] Although existing vertical pre-assembly can simulate real stress conditions, it still faces the following problems: 1. Foundation settlement and deformation: The stacking of multiple sections of overweight steel towers results in large foundation loads and ground settlement; 2. Difficulty in adjustment: The adjustment of steel tower blocks relies on repeated lifting by large cranes, which poses a great safety hazard; 3. Insufficient measurement accuracy: High-altitude measurement is difficult, and the lack of real-time monitoring technology makes cumulative errors difficult to control. 4. Low overall construction efficiency: The construction efficiency of two-segment vertical pre-assembly is low. If multi-segment pre-assembly can be achieved, the efficiency of pre-assembly construction can be greatly improved. 5. Low lifting efficiency: Block steel towers are mostly pre-assembled by lifting the blocks in sections. The blocks are lifted and transported in reverse, resulting in low construction efficiency and high risks of lifting and reverse transportation. Summary of the Invention

[0004] Purpose of the invention: The purpose of the present invention is to propose a vertical pre-assembly construction method for a block-type steel tower to achieve efficient, accurate and safe multi-segment pre-assembly.

[0005] Technical solution: The present invention comprises the following steps:

[0006] Design a pre-assembled base and secure it to the ground;

[0007] Put the blocks of the first segment in place: Place the blocks of the first segment that have passed the processing and inspection on the vertical pre-assembled base;

[0008] One side of the next pre-assembled segment is hoisted in and measured. Once the requirements are met, the steel tower segments are temporarily connected. The same process is used to complete the pre-assembly of the subsequent segments.

[0009] After all the segments are hoisted in, the steel tower segments are fully inspected. After meeting the design and specification requirements, temporary matching parts are installed. After passing the inspection, the segments are moved out of the pre-assembly site one by one.

[0010] The vertical and horizontal permanent ground sample lines laid out on the ground serve as the pre-assembly benchmark for the steel tower.

[0011] Before the segment is hoisted in, the flatness of the top surface of the base connection seat is measured to ensure that the flatness is within 1 mm.

[0012] The first segment uses the vertical and horizontal baselines as the reference to locate the block on the other side of the bottom segment, ensuring that the horizontal height difference of the four points of the baseline marked on the side wall plate is within 1mm, the deviation of the tower section axis is controlled to ≤H / 10000 and less than 5mm, and the misalignment of the axes of adjacent segments is no more than 1mm.

[0013] The axis deviation of the segment interface position is less than or equal to 1mm, and the overall verticality deviation is ≤H / 10000.

[0014] Temporary splicing plates are installed at the ring positions between the segments for fixation.

[0015] When there is a gap between the vertical and horizontal baselines of the blocks, it can be adjusted by adjusting the tooling.

[0016] During the pre-assembly, after the inner and outer blocks of the Ti, Ti+1, and Ti+3 segments are assembled, the vertical and horizontal baselines on the relevant segments are checked according to the pre-assembly drawing, and the vertical and horizontal alignment lines drawn on the wall panel surface are checked to see whether they are consistent with the dimensions shown in the pre-assembly drawing.

[0017] When conducting a comprehensive inspection of the pre-assembled tire, lay out the pre-assembly alignment reference line on the tire frame according to the pre-assembly drawing, lay out the segment support plates, and measure the plane height difference to be within 1mm.

[0018] The steel tower pre-assembly is carried out in a 2+1 vertical pre-assembly mode.

[0019] Beneficial effects: The present invention can achieve a steel tower axis deviation of 1 / 10000H, where H is the pre-assembly height; the tooling system is basically a bolted structure and is reusable, and the non-welding construction reduces damage to the finished product paint surface, achieving high efficiency and environmental protection; the quality is controllable, and there is no residue caused by the removal of welded temporary structures, and the appearance quality pass rate is increased to more than 98%; it innovatively solves the three-segment vertical pre-assembly construction of ultra-high and ultra-large steel towers, fully simulates the bridge installation status, and realizes the bridge erection rehearsal; each round of pre-assembly can be completed within 10 days; it can solve all steel tower vertical pre-assembly problems; the method is simple, the tooling structure is stable, disassembly is convenient, and adjustment is quick, which can significantly improve the efficiency of steel tower manufacturing and construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a flow chart of the present invention;

[0021] Figure 2 It is a schematic diagram of the construction process of the present invention;

[0022] Figure 3 It is a temporary fixing schematic diagram of the present invention;

[0023] Figure 4 It is a schematic diagram of the temporary adjustment device of the present invention;

[0024] Figure 5 It is a schematic diagram of the steel tower block matching part of the present invention;

[0025] Figure 6 This is a schematic diagram of the steel tower pre-assembly inspection line of the present invention;

[0026] Figure 7 This is a layout diagram of the verticality detection points of the steel tower pre-assembly axis of the present invention;

[0027] Figure 8 This is a schematic diagram of the steel tower pre-assembly inspection line of the present invention;

[0028] Figure 9 It is a schematic diagram of the steel tower pre-assembly detection line of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to the accompanying drawings.

[0030] like Figure 1 and Figure 2 As shown, the block-type steel tower vertical pre-assembly construction method of this embodiment solves the low efficiency and poor linear accuracy of traditional horizontal pre-assembly through the reference base, block-by-block adjustment, local fine-tuning, segment connection, and overall tire placement, improves the stability and construction safety of vertical pre-assembly, and solves the problem of multi-segment vertical pre-assembly of ultra-high and ultra-large steel towers. It is suitable for complex working conditions (such as the 3-segment pre-assembly of the steel tower of Zhangjinggao Yangtze River Bridge, with a height of 40.5m and a single pre-assembly load of 1650t), and significantly improves construction efficiency and safety. Specifically, it includes the following steps:

[0031] S1. Base Inspection: Lay permanent vertical and horizontal lines on the ground as a benchmark for pre-assembly of the steel tower. Locate the pre-assembly benchmark base. Measure the top surface flatness of the base connector before hoisting the segments. Use shims to adjust the overall top surface flatness of the base to within 1mm. Before each assembly, inspect the base to ensure that most segments (with minor adjustments to individual segments) meet design and specification requirements, ensuring pre-assembly efficiency.

[0032] S2. Put the blocks of the first segment in place: Place the blocks of the first segment that have passed the processing inspection in a reasonable position on the vertical pre-assembled base. Use the vertical and horizontal baselines as a reference to locate the blocks on the other side of the bottom segment, adjust the port alignment, ensure that there is no misalignment at the interface of the blocks on both sides, check and adjust the interface gap between the two blocks, the baseline alignment, and measure the height, end face size, and verticality of the steel tower segment. Ensure that the horizontal height difference of the four points of the baseline marked on the side wall is within 1mm, the deviation of the tower segment axis is controlled to ≤H / 10000 and less than 5mm, and the misalignment of the adjacent segment axes is no more than 1mm. After meeting the requirements, lock and fix the blocks. Use a special connecting seat to temporarily connect the block to the base to prevent the block from tipping over. Use a horse plate to temporarily connect the two blocks into an integral segment to prevent tipping over while facilitating the subsequent overall lifting of the segment.

[0033] S3. Alignment of blocks in the next segment: transport the blocks of the second segment that have passed the processing inspection to the pre-assembly frame with a hydraulic beam-shifting flat car, and use the longitudinal and transverse baselines and the vertical and transverse baselines of the bottom segment as the reference to position the blocks of the middle segment. First, align the vertical axes of the three sides of the steel tower. The axis deviation at the interface position is less than or equal to 1mm, and the overall verticality deviation is ≤H / 10000. Adjust the panel at the ring mouth to align without misalignment. Install a temporary splicing plate at the ring mouth to fix it to prevent the steel tower from tipping over. Position and assemble the blocks on the other side of the second layer, and perform inspections and adjustments according to the measurement method of the bottom segment to ensure that the corresponding interfaces of the two segments are parallel. Use temporary splicing plates for temporary fixation, such as Figure 3 As shown, safety during steel tower hoisting is ensured, and the same process is used to complete the pre-assembly of the subsequent sections.

[0034] S4. Measure the vertical and horizontal baseline spacing of each block. For positions with slight deviations in the alignment of the upper and lower steel tower blocks, and for individual positions that cannot meet the requirements of the "Manufacturing Rules", special adjustment tools are designed, such as Figure 4 As shown, the two blocks are bolted together through the wall panels and fine-tuned and precisely positioned using jacks. After passing comprehensive inspection, the two blocks are temporarily connected into an integral segment using horse plates.

[0035] S5. Install the ring matching parts between blocks and segments: Check the segment alignment, configure the longitudinal joints between blocks and the ring matching parts between segments, such as Figure 5 shown.

[0036] S6. Overall inspection: The overall inspection is carried out during the period of stable ambient temperature, mainly checking the matching of blocks and segment box openings, axis deviation, etc.

[0037] S7. Marking the alignment lines for bridge installation: To improve the speed and accuracy of steel tower bridge installation and restore the vertical pre-assembly matching state of the steel tower in the factory, after the overall inspection of various points is passed, the alignment lines for bridge installation are marked at the interface of the two tower sections. The alignment lines are scored and punched with a steel needle, and the punched holes are sealed with sealing tape. The installation effect can be checked during the bridge installation.

[0038] During pre-assembly, after the inner and outer blocks of Ti, Ti+1 and Ti+3 segments are assembled, Figure 6 Verify the vertical and horizontal baselines of the relevant segments according to the pre-assembly drawing shown, focusing on verifying whether the vertical and horizontal alignment lines (i.e., baselines) marked on the wall panel surface are consistent with the dimensions shown on the pre-assembly drawing. Conduct a comprehensive inspection of the pre-assembly tire. According to the pre-assembly drawing, lay out the pre-assembly alignment baselines on the tire frame, lay out the segment support plates (i.e., flat supports), and measure the flat height difference to within 1mm.

[0039] The steel tower pre-assembly adopts 2+1 vertical pre-assembly mode. According to the actual situation of the steel tower section, the axis measurement points in the factory are the same as the monitoring arrangement measurement points. One section is set with 12 measurement points, which are 200mm away from the port in the longitudinal direction (height direction). Figure 7 shown.

[0040] like Figure 8 As shown, the inner and outer blocks of the steel tower Ti segment that have passed the inspection and are participating in the pre-assembly are hoisted and reset according to the pre-assembly drawing, and the height of the baseline marked on the side wall plate of the segment is adjusted with a total station to ensure that the height difference error at both ends of the baseline is within ±1mm, and compared with the segment production measurement data to ensure that the horizontal baseline and vertical baseline meet the process requirements.

[0041] The inner and outer blocks of the TDi+1 and TDi+2 segments were hoisted and positioned sequentially. Preliminary inspections were conducted and data was recorded for pre-assembly height, interface misalignment, lateral bend, axis deviation, and segment center distance. Fine-tuning of the tower blocks was performed until all inspection points were within the required tolerances. Coordinate values ​​and relative height differences at the segment measurement points were recorded for cumulative tower accuracy management.

[0042] Install the matching parts according to the positioning dimensions of the matching parts on the pre-assembly drawing. The matching parts are made in pairs to effectively ensure accuracy. Mark the bridge hoisting alignment line at the designated position on the outer wall plate, and mark two interface inspection lines with a spacing of 400mm with the interface as the center. Make clear marks (punch holes) at the intersections of the inspection lines and the segment vertical baselines (four lines). Figure 9 shown.

Claims

1. A vertical pre-assembly construction method for a block-type steel tower, characterized in that: The following steps are involved: Design a pre-assembled base and secure it to the ground; Put the blocks of the first segment in place: Place the blocks of the first segment that have passed the processing and inspection on the vertical pre-assembled base; One side of the next pre-assembled segment is hoisted in and measured. Once the requirements are met, the steel tower segments are temporarily connected. The same process is used to complete the pre-assembly of the subsequent segments. After all the segments are hoisted in, the steel tower segments are fully inspected. After meeting the design and specification requirements, temporary matching parts are installed. After passing the inspection, the segments are moved out of the pre-assembly site one by one.

2. The vertical pre-assembly construction method of a segmented steel tower according to claim 1 is characterized in that: The vertical and horizontal ground sample lines are arranged on the ground as a reference for pre-assembly of the steel tower.

3. The vertical pre-assembly construction method of a segmented steel tower according to claim 1 is characterized in that: Before the segment is hoisted in, the flatness of the top surface of the base connection seat is measured to ensure that the flatness is within 1 mm.

4. The vertical pre-assembly construction method of a segmented steel tower according to claim 2, characterized in that: The first segment uses the vertical and horizontal baselines as the reference to locate the block on the other side of the bottom segment, ensuring that the horizontal height difference of the four points of the baseline marked on the side wall plate is within 1mm, the deviation of the tower section axis is controlled to ≤H / 10000 and less than 5mm, and the misalignment of the axes of adjacent segments is no more than 1mm.

5. The vertical pre-assembly construction method of a segmented steel tower according to claim 1 is characterized in that: The axis deviation of the segment interface position is less than or equal to 1mm, and the overall verticality deviation is ≤H / 10000.

6. The vertical pre-assembly construction method of a segmented steel tower according to claim 1 is characterized in that: Temporary splicing plates are installed at the ring positions between the segments for fixation.

7. The vertical pre-assembly construction method of a segmented steel tower according to claim 1, characterized in that: When there is a gap between the vertical and horizontal baselines of the blocks, it can be adjusted by adjusting the tooling.

8. The vertical pre-assembly construction method of a segmented steel tower according to claim 1, characterized in that: During the pre-assembly, after the inner and outer blocks of the Ti, Ti+1, and Ti+3 segments are assembled, the vertical and horizontal baselines on the relevant segments are checked according to the pre-assembly drawing, and the vertical and horizontal alignment lines drawn on the wall panel surface are checked to see whether they are consistent with the dimensions shown in the pre-assembly drawing.

9. The vertical pre-assembly construction method of a segmented steel tower according to claim 1, characterized in that: When conducting a comprehensive inspection of the pre-assembled tire, lay out the pre-assembly alignment reference line on the tire frame according to the pre-assembly drawing, lay out the segment support plates, and measure the plane height difference to be within 1mm.

10. The vertical pre-assembly construction method of a segmented steel tower according to claim 1, characterized in that: The steel tower pre-assembly adopts a 2+1 vertical pre-assembly mode.

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