A positioning and fine adjustment device for a steel main beam of a consolidation section of a cable-stayed bridge with a double-tower connected consolidation system

Abstract

This invention discloses a positioning and fine-tuning device for the steel main girder of a cable-stayed bridge with a double-tower integrated fixed system, belonging to the field of bridge construction technology. The device includes a pre-embedded support system, an elevation adjustment mechanism, a planar limiting mechanism, a stiffening and stabilizing structure, and a measurement and control system. The pre-embedded support system includes pre-embedded steel supports and their top support plates and vertical plates. The elevation adjustment mechanism uses M50 adjusting bolts penetrating the support plates for vertical fine-tuning. The planar limiting mechanism includes transverse and longitudinal M50 limiting bolts set on the sides of the vertical plates. The stiffening and stabilizing structure enhances stability through stiffening plates, angle steel cross bracing, and diagonal reinforcing bars. The measurement and control system includes various measurement and control points deployed on the steel beam. This invention, through a combination of mechanical fine-tuning and real-time measurement and control, achieves rapid and accurate three-dimensional spatial positioning of large-tonnage steel main girders, effectively solving the problems of low accuracy and poor efficiency in traditional construction methods.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction technology, specifically relating to a positioning and fine-tuning device for the steel main beam of the consolidation section of a cable-stayed bridge with a double-tower integrated consolidation system. Background Technology

[0002] The double-tower, rigidly connected cable-stayed bridge is a widely used bridge type in modern long-span bridges. Its main girder and main tower are rigidly connected in the fixed section, offering advantages such as high structural stiffness and good overall performance. As a critical node for transmitting cable forces, girder loads, and bending moments, the installation accuracy of the steel main girder in the tower-girder connection section directly determines the bridge's final alignment, internal force distribution, and long-term operational safety. Therefore, precise three-dimensional spatial positioning of the steel main girder in this section is a core aspect and a key challenge in the entire bridge construction process.

[0003] In traditional construction, the installation of large-tonnage steel main beams in the fixed section typically involves setting up temporary supports in conjunction with hand-operated hoists or jacks for positioning and adjustment. This method has several limitations: First, hand-operated hoists have low adjustment precision and poor controllability, making it difficult to achieve millimeter-level fine adjustments, and are inefficient, often requiring repeated operations. Second, the temporary support system lacks effective rigid limiting and stabilization measures, making it prone to displacement and instability during hoisting and adjustment, posing significant safety risks. Finally, the entire adjustment process lacks real-time and effective linkage with the measurement system; the measurement, adjustment, and fixing stages are disconnected, making it difficult to form a closed-loop control, resulting in the final installation accuracy failing to meet increasingly stringent design and specification requirements.

[0004] Therefore, this invention proposes a positioning and fine-tuning device for the steel main beam of the consolidation section of a cable-stayed bridge with a double-tower integrated consolidation system to at least partially solve the above-mentioned problems. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, this invention provides a positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system. This device solves the problems of low adjustment accuracy, poor efficiency, and high safety risks associated with traditional methods that use temporary supports and manual hoists for adjustment.

[0006] The objective of this invention can be achieved through the following technical solution: a positioning and fine-tuning device for the steel main beam of the cable-stayed bridge with a double-tower integrated fixed system, comprising a pre-embedded support system, an elevation adjustment mechanism, a plane limiting mechanism, a stiffening and stabilizing structure, and a measurement and control system; the pre-embedded support system is used to provide initial support and limiting of the steel main beam; the elevation adjustment mechanism is disposed on the pre-embedded support system to achieve precise adjustment of the vertical elevation of the steel main beam; the plane limiting mechanism is disposed on the side of the pre-embedded support system to control the lateral and longitudinal positions of the steel main beam; the stiffening and stabilizing structure is used to enhance the overall stability of the pre-embedded support system; and the measurement and control system is used to monitor the installation position of the steel main beam.

[0007] As a preferred embodiment of the present invention, the pre-embedded support system includes a steel support pre-embedded in the main tower beam, a support plate welded to the top of the steel support, and a vertical plate welded to the edge of the support plate.

[0008] As a preferred embodiment of the present invention, the stiffening and stabilizing structure includes a stiffening plate welded to the junction of the support plate and the upright plate, and angle steel cross bracing and diagonal reinforcing bars welded between adjacent steel supports.

[0009] As a preferred embodiment of the present invention, the elevation adjustment mechanism is an adjusting bolt, which penetrates vertically through the support plate. The top of the adjusting bolt contacts the bottom of the steel main beam, and the vertical position of the steel main beam is finely adjusted by screwing it in and out.

[0010] As a preferred embodiment of the present invention, the adjusting bolt is a large-diameter bolt with a specification of M50×160.

[0011] As a preferred embodiment of the present invention, the planar limiting mechanism includes a transverse limiting bolt and a longitudinal limiting bolt, which are respectively disposed on the transverse side and the longitudinal side of the upright plate, and the ends of the transverse limiting bolt and the longitudinal limiting bolt are in contact with the side of the steel main beam.

[0012] As a preferred embodiment of the present invention, the transverse limiting bolt and the longitudinal limiting bolt are large-diameter bolts with a specification of M50×160.

[0013] As a preferred embodiment of the present invention, the measurement and control system includes elevation control points, verticality control points, and small longitudinal beam control points set on the main steel beam. The elevation control points are located at the four corners of the top surface of the main steel beam and at the mid-span position. The verticality control points are located on the side of the main steel beam. The small longitudinal beam control points are located at the ends of the small longitudinal beams of the main steel beam.

[0014] The beneficial effects of this invention are as follows: A pre-embedded support system provides stable and reliable initial support and positioning for the steel main beam; large-diameter elevation adjustment bolts on the support plate enable millimeter-level precise micro-adjustment of the vertical position; and transverse and longitudinal limiting bolts on the sides of the vertical plate effectively control the planar position and verticality of the steel main beam. The stiffening and stabilizing structure composed of stiffening plates, angle steel cross bracing, and diagonal reinforcing bars significantly enhances the overall rigidity and stability of the support system, preventing deviation and instability during construction. Combined with the measurement and control system consisting of control points located at key parts of the steel beam and a total station and level, a real-time feedback and closed-loop control of measurement-adjustment-fixing is formed, ultimately achieving rapid, accurate, and safe high-precision positioning of the large-tonnage steel main beam in three-dimensional space. This effectively solves the technical problems of high adjustment difficulty, low accuracy, poor efficiency, and high safety risks associated with traditional processes. Attached Figure Description

[0015] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0016] Figure 1 This is a schematic diagram of the overall structure of the tower-beam consolidation section of the present invention.

[0017] Figure 2 for Figure 1 Enlarged schematic diagram of the control point layout of the small longitudinal beam at point A.

[0018] Figure 3 for Figure 1 Enlarged schematic diagram of the verticality control point layout at point B.

[0019] Figure 4 This is a schematic diagram of the pre-embedded support system of the present invention.

[0020] Figure 5 for Figure 4 A schematic diagram of the positioning of AA in the middle.

[0021] Figure 6 for Figure 4 Schematic diagram of the layout of elevation control points in the middle BB.

[0022] In the diagram: 100, steel support; 101, support plate; 102, upright plate; 103, stiffening plate; 200, adjusting bolt; 300, limiting bolt; 400, angle steel cross bracing; 500, diagonal tie bar; 600, small longitudinal beam control point; 700, verticality control point; 800, elevation control point. Detailed Implementation

[0023] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0024] Please see Figures 1-6 This embodiment provides a positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system. It includes a pre-embedded support system, an elevation adjustment mechanism, a plane limiting mechanism, a stiffening and stabilizing structure, and a measurement and control system.

[0025] The following, in conjunction with the accompanying drawings, provides a detailed description of the specific structure of the device and its installation method. First, the pre-embedded support system is installed. Before the main tower beam concrete is poured, steel supports 100 are accurately pre-embedded according to the design positions. High-strength steel sections (such as I-beams or H-beams) are used for the steel supports 100. During pre-embedding, positioning is achieved through measurement, and temporary fixing measures are employed to ensure that the steel supports 100 do not shift or tilt during concrete pouring. After the concrete pouring is completed, the top elevation of the steel supports 100 is measured, and leveling is performed using an oxy-acetylene torch to ensure that the top surfaces of each support point are horizontal.

[0026] Next, the support system is reinforced and its components are welded. A support plate 101, made of thick steel plate, is welded to the top of the leveled steel supports 100, providing a support surface for the main steel beam. Vertical plates 102 are welded perpendicularly to the edges of the support plates 101, forming a lateral restraint structure for the main steel beam. To enhance local stiffness, stiffening plates 103 are welded at the junction of the support plates 101 and 102, with continuous welds ensuring a secure connection. Simultaneously, angle steel cross bracing 400 and diagonal reinforcing bars 500 are welded between adjacent steel supports 100. The angle steel cross bracing 400 horizontally connects each steel support 100, forming an overall frame; the diagonal reinforcing bars 500 are arranged diagonally, working together with the angle steel cross bracing 400 to prevent the support system from shifting or becoming unstable under load.

[0027] Next, the elevation adjustment mechanism and the plane limiting mechanism are installed. Threaded holes are pre-drilled in the support plate 101, and adjusting bolts 200 are installed. The adjusting bolts 200 are large-diameter bolts of M50×160 specification, vertically penetrating the support plate 101, with their tops contacting the bottom of the steel main beam. By rotating the adjusting bolts 200 with a wrench or special tool, the vertical elevation of the steel main beam can be precisely controlled, achieving millimeter-level fine adjustments. Limiting bolts 300 are installed on the transverse and longitudinal sides of the vertical plate 102, respectively. The limiting bolts 300 are also of M50×160 specification, with their ends contacting the sides of the steel main beam. By rotating the transverse and longitudinal limiting bolts 300 respectively, the planar position of the steel main beam can be adjusted, controlling its axis and verticality.

[0028] Subsequently, a measurement and control system was set up. Before the main steel beam was hoisted, control points were set up at key locations: elevation control point 800 was located at the four corners of the top surface of the main steel beam and at the mid-span to monitor elevation changes; verticality control point 700 was located on the side of the main steel beam to detect vertical deviations; and longitudinal beam control point 600 was located at the end of the longitudinal beam of the main steel beam to ensure the positioning accuracy of the longitudinal beam. These control points were monitored in real time using instruments such as total stations and levels, and the data was fed back to the operators to guide adjustments to the operation.

[0029] During the fine-tuning process, the measurement and control system forms a closed-loop control flow of measurement-feedback-adjustment-verification. Specifically, measuring instruments (such as total stations and levels) collect data from each control point in real time, and operators determine the direction and amount of adjustment based on the deviation between the data and the design values. The adjustment operation is based on the following principles: Elevation Adjustment: When the elevation control point 800 data shows that the elevation of a certain point on the steel main beam is lower than the design value, the operator uses a wrench or special tool to rotate the adjusting bolt 200 at that point, turning it inward (clockwise) to lift the steel main beam; conversely, if the elevation is too high, the adjusting bolt 200 is turned outward (counterclockwise) to lower the steel main beam. The adjustment amount is controlled according to the size of the deviation; for example, each rotation of the bolt raises or lowers the beam by approximately 1-2 mm. Through multiple fine adjustments, the elevation error is gradually reduced to within ±2 mm.

[0030] Planar Position Adjustment: When the verticality control point 700 or the small longitudinal beam control point 600 shows a lateral or longitudinal offset in the steel main beam, the operator adjusts the lateral limit bolt 300 or the longitudinal limit bolt 300. For example, if the steel main beam shifts to the left, the left lateral limit bolt 300 is screwed in while the right lateral limit bolt 300 is screwed out to push the steel main beam to the right; if a longitudinal offset occurs, the longitudinal limit bolt 300 is adjusted accordingly by screwing in or out. During the adjustment process, the position of the steel main beam is finely adjusted by the pushing and pulling action of the bolts to control the axial deviation within ±1mm.

[0031] Verticality adjustment: Verticality deviation is adjusted in conjunction with the lateral limiting bolts 300 and the longitudinal limiting bolts 300. For example, if the main steel beam tilts inward, the lateral limiting bolts 300 on the corresponding side are screwed in and the longitudinal limiting bolts 300 are adjusted in conjunction to correct the tilt.

[0032] After each adjustment, the measurement system immediately verifies the change by collecting the latest data to check if the deviation has decreased. If the requirements are not met, fine-tuning is performed again based on the new data until the elevation, planar position, and verticality of the steel main beam all reach the design accuracy. The entire adjustment process ensures real-time feedback, precise operation, and rapid convergence.

[0033] During the steel main beam installation phase, a large-tonnage tower crane is used to hoist the steel main beam onto the pre-embedded support system for initial positioning, ensuring that the bottom of the steel main beam is in contact with the adjusting bolts 200 and the sides are close to the limiting bolts 300. Then, fine-tuning is performed: based on measurement data, the adjusting bolts 200 are first operated to adjust the elevation of the steel main beam, controlling the elevation error within ±2mm; then, the transverse and longitudinal limiting bolts 300 are operated to adjust the planar position and verticality of the steel main beam, controlling the axial deviation within ±1mm. Throughout the adjustment process, the measurement system continuously monitors the process, forming a closed-loop control system of measurement-adjustment-verification.

[0034] Finally, the steel beam is fixed and inspected. After fine-tuning to meet the standards, the main steel beam is fixed to the support plate 101 and the upright plate 102 by welding. A symmetrical segmented welding process is used during welding to reduce thermal deformation. After welding is completed, a final measurement and inspection are carried out to ensure the precise positioning of the main steel beam.

[0035] Throughout the fine-tuning process, the measurement and control system plays a crucial decision-making role, key to achieving closed-loop precision control. This system comprises a series of control points deployed on the main steel beam. Regarding elevation control, such as... Figure 6 As shown, 800 elevation control points were set up at key locations such as the four corners of the top surface of the steel main beam and the middle of the span. Surveyors used a high-precision electronic level to cyclically observe these points and fed back the real-time data to the adjustment team. Regarding the control of planar position and verticality, such as... Figure 3 As shown, verticality control points 700 were set up on the side of the steel main beam. A total station was used to measure its three-dimensional coordinates to monitor the beam's axial misalignment and torsion. Furthermore, as... Figure 2 As shown, for the small longitudinal beams connecting the left and right bridge decks, control points 600 are specifically installed at their ends to ensure the installation accuracy of this critical connection. The entire adjustment process constitutes an efficient closed-loop control flow of measurement-feedback-adjustment-verification. Guided by real-time data, each fine-tuning of the bolts is targeted, greatly improving adjustment efficiency and final accuracy.

[0036] Once the monitoring data from the total station and level instrument show that the elevation, axis, and verticality of the steel main beam have met the accuracy standards required by the design and specifications, the fine-tuning operation is complete. At this point, the final fixing operation must be carried out immediately. First, all adjusting bolts 200 and limiting bolts 300 are finally tightened, and if necessary, double nuts can be tightened together to prevent loosening. Then, the bottom plate of the steel main beam and the support plate 101, and the web plate of the steel main beam and the vertical plate 102 are permanently welded and fixed together using pre-set connecting plates or by directly using bevel welding to form rigid joints. The welding operation must follow strict welding procedure qualification requirements and adopt a symmetrical, segmented, multi-pass welding process to control welding deformation and residual stress. After the welding is completed and cooled, a final comprehensive measurement and acceptance is required to record the final bridge alignment data. After confirmation that there are no errors, the positioning and installation work of the entire tower-beam fixed section steel main beam is successfully completed.

[0037] In summary, this invention, through the synergistic action of five modules—a pre-embedded support system, an elevation adjustment mechanism, a plane limiting mechanism, a stiffening and stabilizing structure, and a measurement and control system—forms a complete, efficient, and reliable solution for the precise positioning of large-tonnage steel main girders. It successfully transforms the extensive, traditional manual adjustment into precise mechanized and digital control, ensuring not only the construction quality and structural safety of key bridge nodes but also significantly improving construction efficiency and reducing operational safety risks. This device achieves high-precision mechanized adjustment and digital control of the steel main girder and is suitable for the construction of the tower-girder fixed sections of various large-span cable-stayed bridges.

[0038] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A positioning and fine adjustment device for a steel main girder of a consolidation section of a cable-stayed bridge of a double-tower connected consolidation system, characterized in that, The system includes a pre-embedded support system, an elevation adjustment mechanism, a plane limiting mechanism, a stiffening and stabilizing structure, and a measurement and control system. The pre-embedded support system provides initial support and positioning for the steel main beam. The elevation adjustment mechanism, mounted on the pre-embedded support system, allows for precise adjustment of the vertical elevation of the steel main beam. The plane limiting mechanism, located on the side of the pre-embedded support system, controls the lateral and longitudinal positions of the steel main beam. The stiffening and stabilizing structure enhances the overall stability of the pre-embedded support system. The measurement and control system monitors the installation position of the steel main beam.

2. The positioning and fine adjustment device for the steel main girder of the consolidation section of the cable-stayed bridge with the double-tower connected consolidation system according to claim 1, characterized in that, The pre-embedded support system includes a steel support pre-embedded in the main tower beam, a support plate welded to the top of the steel support, and a vertical plate welded to the edge of the support plate.

3. The positioning and fine adjustment device for the steel girder of the consolidation section of the cable-stayed bridge with the double-tower connected consolidation system according to claim 2, characterized in that, The stiffening and stabilizing structure includes a stiffening plate welded to the junction of the support plate and the upright plate, and angle steel cross bracing and diagonal reinforcing bars welded between adjacent steel supports.

4. The positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system according to claim 2, characterized in that, The elevation adjustment mechanism is an adjusting bolt, which penetrates vertically through the support plate. The top of the adjusting bolt contacts the bottom of the steel main beam, and the vertical position of the steel main beam can be finely adjusted by screwing it in and out.

5. The positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system according to claim 4, characterized in that, The adjusting bolt is a large-diameter bolt with a specification of M50×160.

6. The positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system according to claim 2, characterized in that, The planar limiting mechanism includes a lateral limiting bolt and a longitudinal limiting bolt, which are respectively disposed on the lateral side and the longitudinal side of the upright plate. The ends of the lateral limiting bolt and the longitudinal limiting bolt are in contact with the side of the steel main beam.

7. The positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system according to claim 6, characterized in that, The transverse and longitudinal limiting bolts are large-diameter bolts with a specification of M50×160.

8. The positioning and fine-tuning device for the steel main beam of the fixed section of a cable-stayed bridge with a double-tower integrated fixed system according to claim 1, characterized in that, The measurement and control system includes elevation control points, verticality control points, and small longitudinal beam control points set on the main steel beam. The elevation control points are located at the four corners of the top surface of the main steel beam and at the mid-span position. The verticality control points are located on the side of the main steel beam. The small longitudinal beam control points are located at the ends of the small longitudinal beams of the main steel beam.

Images