Long-cantilever large-longitudinal-slope multi-point cable-stayed buckling auxiliary rotation construction method and device

Abstract

The invention discloses a long-cantilever large-longitudinal-slope multi-point cable-stayed buckling auxiliary rotation construction method which comprises the steps that transverse supporting beams, longitudinal supporting beams and stand column towers are sequentially installed on steel box beams, transverse supporting frames are welded between the stand column towers, and after steel anchor beams are hoisted to the tops of the stand column towers to the designed positions to be welded and fixed, inhaul cables are installed through hoisting rings and pin shafts; after the rotation of the steel box girder is completed and the girder falling of the steel box girder is completed, the inhaul cables are gradually and symmetrically removed from the outer side to the cable bent tower, the pin shafts at the connecting positions of the lower anchor box and the lifting lugs are removed until all the inhaul cables are removed, and the connecting weld joints between the steel anchor girder and the top of the stand column tower are cut off. The invention further provides a construction device which comprises the cable bent tower, the inhaul cable and the lower anchor box, and the lower anchor box is connected with the lifting lug fixed to the steel box girder through the pin shaft. It is effectively guaranteed that the large-span steel box girder is always kept stable in the rotating process, meanwhile, the lower anchor box at the connecting end of the inhaul cable is connected with the lifting lug through the pin shaft, the inhaul cable is convenient to disassemble and assemble, and then the construction efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of bridge rotation construction technology, and in particular to a method and device for auxiliary rotation construction using multi-point inclined cable fastening on long cantilever and steep longitudinal slope. Background Technology

[0002] In recent years, the application of bridge rotation construction technology has become increasingly widespread. In order to meet more complex traffic needs, the rotation of single small symmetrical bridges has evolved into the rotation of various large-tonnage asymmetrical bridges. Due to the lateral imbalance caused by curved bridges and the longitudinal imbalance caused by the longitudinal asymmetrical structure of the bridge, traditional construction technology can no longer fully meet the stability requirements of the bridge rotation process.

[0003] In existing technologies, during the rotation construction of pier-top rotating bridges with steep longitudinal slopes in China, the stress at the beam end anchoring points is excessively concentrated. Furthermore, the dismantling of the steel box girder assembly supports causes a redistribution of stress within the support system, posing certain safety risks. Secondly, the steel box girder construction process involves steel beam assembly, inclined cable anchoring, pier-top rotation, and high-level beam lowering, making the process complex and alignment control difficult. To address these construction challenges, there is an urgent need to improve the multi-point inclined cable anchoring assisted rotation construction method for long cantilever bridges with steep longitudinal slopes. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method and device for constructing a long-span steel box girder with a multi-point inclined cable-stayed suspension system for rotation. Before rotation, a pylon is installed at the middle of the top of the steel box girder, and lifting lugs are symmetrically arranged on both sides. Several cables are sequentially fixed between the top of the pylon and the lifting lugs. The tension of each steel strand is calculated, and each cable is suspended using an equal-tensioning method to ensure uniformity of cable tension. This effectively ensures the stability of the long-span steel box girder during rotation. Simultaneously, the lower anchor box at the cable connection end is connected to the lifting lug via a pin, facilitating the installation and removal of the cables and thus improving construction efficiency.

[0005] This invention provides the following solutions: In a first aspect, the present invention provides a method for constructing long cantilevered, steep longitudinal slope structures using multi-point inclined cable-stayed auxiliary rotation methods, the method comprising the following steps: S1. After the steel box girder at the main pier is installed, a transverse support beam is installed in the middle of the steel box girder; S2. Install longitudinal support beams on top of transverse support beams; S3. Install the column tower: The bottom of the column tower is welded to the longitudinal support beam using steel plates. Slanted legs are welded to the bottom of the column tower, and the two ends of the slanted legs are connected to the side of the column tower and the longitudinal support beam respectively to ensure the stability of the column tower. The column tower adopts a modular structure composed of a set of column tower sections longitudinally spliced ​​together. Each column tower section is connected from bottom to top using flanges and high-strength bolts. S4. Repeat steps S1 to S3 to complete the installation of each set of column towers, and weld cross braces between the column towers. S5. Hoist the steel anchor beam to the top of the column tower to the designed position and then weld and fix it. This completes the installation of the cable tower. S6. Arrange lifting lugs symmetrically along the steel box girder on both sides of the tower, with the same number of cables to be installed. Install the cables from the top of the tower to both sides. The top of the cable is fixed to the steel anchor beam, which serves as the tensioning end, and the end is fixed to the lower anchor box, which serves as the anchoring end, through the extrusion head. The lower anchor box is connected to the lifting lugs through the pin shaft. The cables are tensioned symmetrically in stages from the middle to both ends. During the tensioning process, monitor the deformation of the tower and the steel box girder in real time to ensure that the tower and the steel box girder meet the design requirements. S7. After the steel box girder has been rotated and lowered, gradually and symmetrically release the cables from the outside to the tower, and remove the pins at the lower anchor box and the connection of the lifting lug until all cables are released. S8. Cut off the connecting weld between the steel anchor beam and the top of the column tower, remove the steel anchor beam, and then remove the reinforcing bolts on the flanges between the column towers. Remove each group of column towers from top to bottom. When removing the column tower section at the bottom, cut off the diagonal leg first. Finally, the remaining transverse support beams and longitudinal support beams are hoisted in sequence after their connecting welds are cut off, until the entire tower is completely dismantled.

[0006] Furthermore, in step S1, before installing the transverse support beam and in step S2, before installing the longitudinal support beam, surveying instruments are used to lay out the positions and determine the locations before hoisting.

[0007] Furthermore, in step S4, after each set of column towers is installed, a total station is used to check the installation accuracy of the column towers. If the requirements are not met, the deviation is corrected in time, and the installation of the next set of column towers is carried out only after the requirements are met.

[0008] Furthermore, in step S6, the lifting lugs are fixed to the steel box girder by embedded parts.

[0009] Furthermore, step S6 involves attaching each cable using the equivalent tensioning method.

[0010] Secondly, the present invention also provides a long cantilever, long longitudinal slope multi-point inclined cable-stayed auxiliary rotation construction device based on the method, including a cable tower, cables, and a lower anchor box. The bottom of the cable tower is fixed to the steel box girder through a transverse support beam and a longitudinal support beam installed on the transverse support beam. The top of the cable tower is provided with a steel anchor beam, which is connected to one end of the cable as the tension end. The lower anchor box is connected to the other end of the cable as the anchoring end. The lower anchor box is connected to the lifting lug fixed to the steel box girder through a pin.

[0011] Furthermore, the tower includes a set of column towers, which adopt a modular structure composed of a set of column tower segments longitudinally spliced ​​together. The column tower segments are connected by flanges and high-strength bolts.

[0012] Furthermore, the bottom of the tower is equipped with sloping legs, with the two ends of the sloping legs connecting the side of the tower and the longitudinal support beam, respectively.

[0013] Furthermore, the lifting lugs are fixed to the steel box girder via embedded parts.

[0014] Furthermore, the transverse support beams are fixed to the steel box girder using mounting plates.

[0015] The beneficial effects of this invention based on its technical solution are as follows: (1) Before the rotation of a large-span steel box girder, the present invention sets up a pylon at the middle position of the top of the steel box girder and arranges symmetrical lugs on both sides of it. Several cables are fixedly installed between the top of the pylon and the lugs in sequence for connection. The tension of each steel strand is calculated and each cable is hung using the equal tension method to ensure the uniformity of the cable force of each cable, which effectively ensures that the large-span steel box girder remains stable during the rotation process. (2) The present invention uses the lower anchor box of the cable connection end to be connected to the lifting lug through the pin shaft, and the cable tower is spliced ​​by modular column tower, which facilitates the assembly and disassembly of the cable and the cable tower, thereby improving the construction efficiency. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention; Figure 2 This is a front view of the cable tower according to an embodiment of the present invention; Figure 3 This is a left view of the Sota according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the steel anchor beam and cable connection structure according to an embodiment of the present invention; Figure 5 for Figure 1 Enlarged view of point A; Figure 6 for Figure 1 Enlarged view at point B.

[0018] In the diagram: 1-Steel box girder, 2-Cable, 3-Tower, 31-Steel anchor beam, 3101-Angled opening, 32-Column tower, 33-Angled leg, 34-Longitudinal support beam, 35-Transverse support beam, 36-Plate plate, 37-Flange, 38-Horizontal brace, 4-Lower anchor box, 5-Lifting lug, 6-Pin shaft. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the protection scope of the embodiments of the present invention.

[0020] Reference Figures 1 to 6 This embodiment provides a multi-point inclined cable-stayed auxiliary rotation construction method for long cantilever and steep longitudinal slope, the method including the following steps: S1. After the steel box girder 1 at the main pier is installed, a transverse support beam 35 is installed in the middle of the steel box girder 1 using a mounting plate 36. In this embodiment, the transverse support beam 35 is made of 2I40a I-beams with a length of 6m. The mounting plates 36 are used to weld the beams to the top of the steel box girder 1 on both sides of the I-beams. Before installation, a measuring instrument is used to lay out the beams and determine the position before hoisting.

[0021] S2. Install the longitudinal support beam 34 on top of the transverse support beam 35. In this embodiment, the longitudinal support beam 34 is made of 3HM588 steel, with a length of 12m. Before installation, a measuring instrument is used to lay out the beam, and the position is determined before hoisting. The longitudinal support beam 34 is welded to the transverse support beam 35 through stiffening plates.

[0022] S3. Install the column tower 32: The bottom of the column tower 32 is welded to the longitudinal support beam 34 using a 1.2m×1.2m steel plate. Slanted legs 33 are welded to the bottom of the column tower 32 and fixed symmetrically on both sides of the column tower 32. They are also welded to the top of the longitudinal support beam 34 to ensure the stability of the column tower 32.

[0023] The column tower 32 adopts a modular structure composed of a set of column tower sections longitudinally spliced ​​together. Each column tower section is connected from bottom to top using flanges 37 and high-strength bolts. Each column tower section is first assembled into a whole in the factory and then hoisted and installed on site in sequence.

[0024] S4. Repeat steps S1 to S3 to complete the installation of each group of column towers 32, and weld the cross bracing 38 between the column towers 32. After the installation of each group of column towers 32 is completed, the installation accuracy of the cable tower 3 should be checked with a total station. If the requirements are not met, correct them in time. After the requirements are met, proceed with the installation of the next group of column towers 32.

[0025] S5. After hoisting the steel anchor beam 31 to the top of the column tower 32 to the designed position, weld and fix it: The steel anchor beam 31 is formed by welding 40mm steel plates. Both ends of the inner side of the steel anchor beam 31 have beveled openings 3101 for fixing the cables 2. The inclination angle of the beveled openings 3101 matches the inclination angle of the cables. First, it is fabricated as a whole on site. Then, the steel anchor beam 31 is hoisted sequentially onto the installed column tower 32. After positioning according to the design position, the top of the column tower 32 is welded and fixed to the steel anchor beam 31 to ensure the stability of the steel anchor beam 31. This completes the installation of the cable tower 3.

[0026] S6. Arrange lifting lugs 5 symmetrically along the steel box girder 1 on both sides of the tower 3, with the same number of lugs as the cables to be installed. Install cables 2 from the top of the tower 3 to both sides. The top of the cable 2 is fixed to the steel anchor beam 31, which serves as the tensioning end, and the end is fixed to the lower anchor box 4, which serves as the anchoring end, through the extrusion head. The lower anchor box 4 is connected to the lifting lugs 5 through the pin 6. The cables 2 are tensioned symmetrically in stages from the middle to both ends. During the tensioning process, monitor the deformation of the tower 3 and the steel box girder 1 in real time to ensure that the tower 3 and the steel box girder 1 meet the design requirements.

[0027] S7. After the steel box girder 1 has been rotated and lowered, gradually and symmetrically release the cables 2 from the outside to the tower 3, and remove the pins 6 at the connection of the lower anchor box 4 and the lifting lug 5 until all cables 2 are released. The dismantling is convenient.

[0028] S8. Cut off the connecting weld between the steel anchor beam 31 and the top of the column tower 32, remove the steel anchor beam 31, and then remove the reinforcing bolts on the flange 37 between the column towers 32. Remove each group of column towers 32 from top to bottom. When removing the column tower segment at the bottom of the column tower 32, cut off the diagonal leg 33 first. Finally, the remaining transverse support beam 35 and longitudinal support beam 34 are hoisted in sequence after their connecting welds are cut off, until the entire tower 3 is completely removed.

[0029] This invention also provides a multi-point inclined cable-stayed auxiliary rotation construction device for long cantilever, steep longitudinal slopes based on the aforementioned method, comprising a pylon 3, cables 2, and a lower anchor box 4. The pylon 3 includes a set of column towers 32, which adopts a modular structure composed of longitudinally spliced ​​column tower sections. The column tower sections are connected by flanges 37 and high-strength bolts. The bottom of the pylon 3 is provided with inclined legs 33, the two ends of which are respectively connected to the side of the pylon 3 and the longitudinal support beam 34.

[0030] The bottom of the pylon 3 is fixed to the steel box girder 1 via a transverse support beam 35 and a longitudinal support beam 34 installed on the transverse support beam 35. The transverse support beam 35 is fixed to the steel box girder 1 via a mounting plate 36. The top of the pylon 3 is provided with a steel anchor beam 31, which serves as the tension end and is connected to one end of the cable 2. The lower anchor box 4 serves as the anchoring end and is connected to the other end of the cable 2. The lower anchor box 4 is connected to a lifting lug 5 fixed to the steel box girder 1 via a pin 6. The lifting lug 5 is fixed to the steel box girder 1 via embedded parts.

[0031] This invention connects the top of the pylon to the lifting lugs with several cables in sequence. During installation, the uniformity of the cable tension in each cable is ensured, effectively guaranteeing the stability of the large-span steel box girder during rotation. At the same time, the pylon uses modular column towers for splicing, and the lower anchor box at the cable connection end is connected to the lifting lugs by pins, which facilitates disassembly and assembly during construction, thereby improving construction efficiency.

[0032] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0033] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A construction method for long cantilever, steep longitudinal slope construction using multi-point inclined cable-stayed auxiliary rotation, characterized in that: The method includes the following steps: S1. After the steel box girder (1) at the main pier is installed, a transverse support beam (35) is installed in the middle of the steel box girder (1). S2. Install a longitudinal support beam (34) on the transverse support beam (35). S3. Install the column tower (32): The bottom of the column tower (32) is welded to the longitudinal support beam (34) using steel plates. An inclined leg (33) is welded to the bottom of the column tower (32). The two ends of the inclined leg (33) are connected to the side of the column tower (32) and the longitudinal support beam (34) respectively to ensure the stability of the column tower (32). The column tower (32) adopts a modular structure composed of a set of column tower sections longitudinally spliced. Each column tower section is connected from bottom to top by flanges (37) and high-strength bolts. S4. Repeat steps S1 to S3 to complete the installation of each set of column towers (32) and weld cross bracing (38) between column towers (32). S5. Hoist the steel anchor beam (31) to the top of the column tower (32) to the design position and then weld and fix it. This completes the installation of the cable tower (3). S6. Arrange lifting lugs (5) on both sides of the tower (3) along the steel box girder (1) in a symmetrical manner with the same number of cables (2) to be installed. Install cables (2) from the top of the tower (3) to both sides. The top of the cable (2) is fixed to the steel anchor beam (31) as the tensioning end, and the end is fixed to the lower anchor box (4) as the anchoring end through the extrusion head. The lower anchor box (4) is connected to the lifting lugs (5) through the pin (6). The cables (2) are tensioned symmetrically in stages from the middle to both ends. During the tensioning process, monitor the deformation of the tower (3) and the steel box girder (1) in real time to ensure that the tower (3) and the steel box girder (1) meet the design requirements. S7. After the steel box girder (1) has been rotated and the steel box girder (1) has been lowered, gradually and symmetrically release the cables (2) from the outside to the tower (3), and remove the pins (6) at the connection of the lower anchor box (4) and the lifting lug (5) until all cables (2) are released. S8. Cut off the connecting weld between the steel anchor beam (31) and the top of the column tower (32), remove the steel anchor beam (31), and then remove the reinforcing bolts on the flange (37) between the column towers (32). Remove each group of column towers (32) from top to bottom. When removing the column tower section at the bottom of the column tower (32), cut off the diagonal leg (33) first. Finally, the remaining transverse support beam (35) and longitudinal support beam (34) are hoisted in sequence after cutting off their connecting welds until the entire tower (3) is completely removed.

2. The construction method for long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation as described in claim 1, is characterized in that: Before installing the transverse support beam (35) in step S1 and the longitudinal support beam (34) in step S2, the beams are laid out using measuring instruments to determine their positions before hoisting.

3. The construction method for long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation as described in claim 1, is characterized in that: In step S4, after each set of column towers (32) is installed, a total station is used to check the installation accuracy of the column towers (32). If the requirements are not met, the deviation is corrected in time, and the next set of column towers (32) is installed only after the requirements are met.

4. The construction method for long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation as described in claim 1, is characterized in that: In step S6, the lifting lug (5) is fixed to the steel box girder (1) by the embedded parts.

5. The construction method for long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation as described in claim 1, is characterized in that: Step S6 uses the equivalent tensioning method to hang each cable (2).

6. A multi-point inclined cable-stayed auxiliary rotation construction device for long cantilevered long longitudinal slopes based on the method of claim 1, characterized in that: The structure includes a tower (3), a cable (2), and a lower anchor box (4). The bottom of the tower (3) is fixed to the steel box girder (1) by a transverse support beam (35) and a longitudinal support beam (34) installed on the transverse support beam (35). The top of the tower (3) is provided with a steel anchor beam (31). The steel anchor beam (31) is connected to one end of the cable (2) as the tension end, and the lower anchor box (4) is connected to the other end of the cable (2) as the anchoring end. The lower anchor box (4) is connected to the lug (5) fixed to the steel box girder (1) by a pin (6).

7. The long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation construction device according to claim 6, characterized in that: The tower (3) includes a set of column towers (32). The column towers (32) adopt a modular structure composed of a set of column tower segments spliced ​​longitudinally. The column tower segments are connected by flanges (37) and high-strength bolts.

8. The long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation construction device according to claim 6, characterized in that: The bottom of the tower (3) is provided with inclined legs (33), and the two ends of the inclined legs (33) are connected to the side of the tower (3) and the longitudinal support beam (34) respectively.

9. The long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation construction device according to claim 6, characterized in that: The lifting lug (5) is fixed to the steel box girder (1) by embedded parts.

10. The long cantilever, large longitudinal slope multi-point inclined cable-stayed auxiliary rotation construction device according to claim 6, characterized in that: The transverse support beam (35) is fixed to the steel box girder (1) by means of a mounting plate (36).

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