A slewing device and construction method for a solid-web cantilever steel beam in a slewing bridge

Abstract

The present invention discloses a swivel device and construction method for a solid-web cantilever steel beam in a swivel bridge. The swivel device is located at the bottom of the pier, and a solid-web cantilever steel beam and a support foot are used to provide lateral support for the swivel bridge. The cantilever steel beams are arranged at intervals of 30°, 45° or 60°. The solid-web cantilever steel beam is connected to the swivel bridge by a steel sleeve. The inner side of the steel sleeve is provided with rib plates, and the connection with the cantilever steel beam is provided with holes through which bolts can pass. The advantages of the present invention are as follows: the overall effect is achieved by using inner and outer ring beams transversely for the cantilever steel beam, and the steel sleeve can be used as a formwork; when the bridge is swiveled, the steel strands are wound around the outer ring beam and the middle part of the outside of the end of the cantilever steel beam to provide power for the swivel bridge; the structure has reasonable stress, convenient construction, effectively reduces the concrete pouring volume of the swivel structure, improves the stability of the swivel structure, and can also realize the recyclability of part of the swivel structure, reflecting the concept of green and sustainable development of construction, and is conducive to the innovation and development of the bridge swivel project.

Description

Technical Field

[0001] The present invention relates to the technical field of bridges, and specifically refers to a rotating device and construction method for a solid-web cantilever steel beam in a rotating bridge. Background Art

[0002] At present, many engineering constructions require the support of rotating construction technology. Rotating construction is not only widely used in the bridge engineering construction in high mountains and valleys, but also widely applied in the overpass railway crossing projects in large cities, and has played an important role. It can not only well and quickly adapt to the bridge construction under special conditions, but also greatly guarantee the progress and quality of the project. This technology can achieve rapid crossing of existing traffic lines and has little impact on the operation of the lower lines. It is an indispensable important engineering technology in the current railway and highway bridge construction.

[0003] The bridge rotating system mainly consists of a lower bearing platform, a spherical hinge, a slideway, a supporting foot, an upper bearing platform, a rotating disc and a traction system. In order to ensure the stability of the rotating structure and prevent overturning, the supporting device is crucial. Therefore, the upper bearing platform needs to have sufficient thickness, which increases the engineering quantity and the rotating weight, and at the same time will deepen the foundation pit depth and increase the additional cost.

[0004] Therefore, it is necessary to propose a new type of bridge rotating support device, which can not only reduce the concrete pouring engineering quantity, but also improve the stability of the rotating structure. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems mentioned in the background art, and provide a rotating device and construction method for a solid-web cantilever steel beam in a rotating bridge.

[0006] To solve the above technical problems, the technical solution provided by the present invention is: a rotating device for a solid-web cantilever steel beam in a rotating bridge, the rotating device is located at the bottom of the bridge pier, and includes a spherical hinge, a cantilever steel beam, a steel sleeve, a supporting foot, a slideway, an outer ring beam, an inner ring beam and a traction cable;

[0007] The spherical hinge includes an upper spherical hinge and a lower spherical hinge, and is arranged at the bottom of the bridge pier or the top of the bearing platform. The steel sleeve is arranged at the lower part of the bridge pier. The cantilever steel beams are arranged at intervals of 45°, 60° or 90° along the outside of the bridge pier. One end of the cantilever steel beam is fixed on the steel sleeve, and the lower part of the other end of the cantilever steel beam is fixed with a supporting foot. The traction cable is wound around the outside of the outer ring beam.

[0008] As a preferred solution, the steel sleeve wraps the outside of the bridge pier. The inside of the steel sleeve is provided with vertical partitions and transverse rib plates. The outside of the steel sleeve is provided with end plates for connecting with the cantilever steel beam. There are holes at the connection between the end plate of the steel sleeve and the cantilever steel beam for high-strength bolt connection.

[0009] As a preferred solution, the cantilever steel beam has an I-shaped, box-shaped or channel-shaped cross-section, and stiffeners are provided at the web of the cantilever steel beam.

[0010] As a preferred solution, the vertical partitions and transverse ribs of the steel sleeve are provided with holes with a size of 5 cm to 30 cm. Reinforcing bars are arranged in the pier. Holes are provided at the intersections of the reinforcing bars with the vertical partitions and transverse ribs, and the reinforcing bars penetrate through the holes.

[0011] As a preferred solution, the support feet are composed of a single steel pipe or a pair of steel pipes. The pair of steel pipes are connected by two flat steel plates. Concrete is filled in the steel pipes or vertical stiffeners are arranged inside the pipes; bolt holes are provided at the connection between the support feet and the cantilever steel beam, and high-strength bolts are used to connect the support feet and the cantilever steel beam.

[0012] As a preferred solution, a number of inner ring beams are arranged at the mid-span of the cantilever steel beam, and an outer ring beam is arranged at the far end of the overhang. The inner ring beams have an I-shaped, box-shaped or channel-shaped cross-section, and the outer ring beams have an I-shaped, box-shaped or channel-shaped cross-section.

[0013] As a preferred solution, holes are provided at the connections between the inner ring beams, the outer ring beams and the cantilever steel beam for connection with high-strength bolts.

[0014] As a preferred solution, grooves for preventing the traction rope from slipping out are provided on the outer side of the outer ring beam and the outer side of the end of the cantilever steel beam.

[0015] As a preferred solution, vertical reinforcing bars extend from the lower part of the pier, and corresponding vertical reinforcing bars are arranged on the upper part of the bearing platform. After the rotation is completed, the vertical reinforcing bars of the pier and the bearing platform are connected.

[0016] A construction method for a rotating device of a solid-web cantilever steel beam in a rotating bridge specifically includes the following steps:

[0017] (1) Pile foundation construction: Drive steel pipe piles for foundation pit protection around the foundation pit, excavate the bearing platform space downward according to the designed height, use a rotary drilling rig to excavate the pile holes, place the steel reinforcement cages, and pour pile foundation concrete;

[0018] (2) First pouring of the bearing platform: After tying the steel bars of the bearing platform, conduct the first pouring of concrete for the bearing platform;

[0019] (3) Installation of the lower spherical hinge, slideway and second pouring of the bearing platform: After the bearing platform concrete reaches the specified strength, place the support steel frames of the slideway and the spherical hinge, position the support steel frames of the slideway and the spherical hinge, tie the steel bars of the lower bearing platform and the steel bars of the reaction seat, and then complete the second concrete pouring of the bearing platform, and then carry out curing;

[0020] (4) Installation of the upper spherical hinge: Clean the debris in the lower spherical hinge, then lay the polytetrafluoroethylene slider, apply butter for lubrication, hoist the upper spherical hinge, and wind the tape at the gap of the spherical hinge to prevent debris from entering;

[0021] (5) Installation of the temporary fixing device: Place the sand box at the designed position and set up the support frame for the steel sleeve;

[0022] (6) Installation of the steel sleeve, cantilever steel beam and support feet: Place the support feet on the slideway according to the specified position, hoist the cantilever steel beam, connect it with the steel sleeve steel formwork using high-strength bolts, pad a rubber pad between the cantilever steel beam and the support feet, fine-tune the gap, and then connect the cantilever steel beam and the support feet with bolts;

[0023] (7) Splicing and installation of the cantilever steel beam and the inner and outer ring beams: After all the cantilever steel beams are installed in place, connect the cantilever steel beam with the inner and outer ring beams using bolts;

[0024] (8) Pier construction: Set up the pier formwork, bind the steel bars, check the stability of the support device and whether the bolts are loose, then pour the pier concrete. After the pier concrete reaches the strength requirement, remove the sand box and the steel sleeve support of the temporary fixing device at the bottom of the pier, and start the construction of the bridge deck structure;

[0025] (9) Main beam construction: Set up the formwork scaffolding for the main beam, set up the formwork, bind the steel bars, and then pour the main beam concrete;

[0026] (10) Installation of the traction cable: Install the traction rope at the outer anchorage of the outer ring beam and the cantilever steel beam, and pass the other end of the traction rope into the traction machines on both sides of the bearing platform;

[0027] (11) Rotation: Before rotation, check the bolt connection of the steel sleeve, cantilever steel beam, inner and outer ring beams and support feet in the node area again. After the rotation starts, slowly tension the traction rope, and observe the reading of the pressure sensor between the cantilever steel beam and the support feet in real time. Adjust the counterweight in time when there is a large eccentricity;

[0028] (12) Pouring of the pedestal concrete: After the rotation is completed, weld the connecting steel bars between the lower part of the upper steel sleeve and the upper part of the lower bearing platform, arrange the distribution steel bars along the periphery of the steel sleeve, and weld them with the reserved steel bars of the lower bearing platform. Set up the pedestal formwork and pour the concrete. After the concrete reaches the strength requirement, remove the cantilever steel beam and the support feet and recycle them;

[0029] (13) Removal of the cantilever steel beam and the support feet: After the bridge rotation is completed, first remove the cantilever steel beam and the inner and outer ring beams, and then remove the support feet and recycle them.

[0030] The advantages of the present invention compared with the prior art are as follows: By improving the materials and types of the support device, the fabrication of the upper bearing platform is eliminated. At the same time, the support device is moved outwards, increasing the length of the lever arm and further enhancing the stability of the rotating structure. It can effectively reduce the construction efficiency of the concrete at the bottom turntable of the pier and is more economical and reliable. Meanwhile, the lever arm length of the support system is expanded, improving the stability of the rotating T-structure. The steel sleeve can also be used as a formwork. When the bridge rotates, the steel strands are wound around the middle part of the outer side of the outer ring beam and the end of the cantilever steel beam to provide power for the rotating bridge. This structure has reasonable stress, convenient construction, effectively reduces the volume of concrete pouring of the rotating structure, improves the stability of the rotating structure, and can also realize the recyclability of part of the rotating structure, reflecting the concept of green and sustainable development of architecture and being conducive to the innovation and development of bridge rotation projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic structural diagram of the rotating device of the present invention.

[0032] Figure 2 is a schematic connection structure diagram of the cantilever steel beam and the steel sleeve of the present invention.

[0033] Figure 3 is a schematic structural diagram of the cantilever steel beam segment of the present invention.

[0034] Figure 4 is a schematic structural diagram of the outer ring beam segment of the present invention.

[0035] Figure 5 is a schematic structural diagram of the inner ring beam segment of the present invention.

[0036] Figure 6 is a schematic connection structure diagram of the steel sleeve and the pier of the present invention.

[0037] Figure 7 is a schematic layout diagram of the pedestal steel bars of the steel sleeve and the lower bearing platform of the present invention.

[0038] Figure 8 is a schematic structural diagram of the supporting foot of the present invention.

[0039] As shown in the figure: 11 - rotating T-structure; 12 - steel sleeve; 21 - cantilever steel beam; 22 - supporting foot; 23 - slideway; 24 - inner ring beam; 25 - outer ring beam; 31 - lower bearing platform; 32 - reaction seat; 33 - towing cable. DETAILED DESCRIPTION OF THE INVENTION

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Components of the embodiments of the present invention generally described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0041] In the description of the embodiments of the present invention, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0042] In addition, if terms such as "horizontal", "vertical", "overhanging", etc. do not mean that the component must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0043] In the description of the embodiments of the present invention, "a plurality of" represents at least two.

[0044] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "connected" are understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] Combined with the accompanying drawings, a swivel device for a solid-web cantilever steel beam in a swivel bridge, the swivel device is located at the bottom of the pier and includes a spherical hinge, a cantilever steel beam 21, a steel sleeve 12, a support foot 22, a slideway 23, an outer ring beam 25, an inner ring beam 24, and a traction cable 33.

[0046] The described spherical hinge includes an upper spherical hinge and a lower spherical hinge, and is arranged at the bottom of the bridge pier or the top of the bearing platform. The steel sleeve 12 is arranged at the lower part of the bridge pier. The cantilever steel beams 21 are arranged at intervals of 45°, 60°, or 90° along the outer side of the bridge pier. One end of the cantilever steel beam 21 is fixed on the steel sleeve 12, and a lower fixed support leg 22 is fixed at the other end of the cantilever steel beam 21. The traction cable 33 is wound around the outer side of the outer ring beam 25.

[0047] The steel sleeve 12 is wrapped around the outer side of the bridge pier. Vertical partition plates and transverse rib plates are arranged inside the steel sleeve 12. End plates for connecting with the cantilever steel beam 21 are arranged on the outer side of the steel sleeve 12. Holes are arranged at the connection between the end plate of the steel sleeve 12 and the cantilever steel beam 21 for high-strength bolt connection.

[0048] The cantilever steel beam 21 has an I-shaped, box-shaped, or channel-shaped cross-section, and stiffening ribs are arranged at the web of the cantilever steel beam 21.

[0049] Holes with a size of 5 cm to 30 cm are arranged in the vertical partition plates and transverse rib plates of the steel sleeve 12. Reinforcing bars are arranged inside the bridge pier. Holes are arranged at the intersections of the reinforcing bars with the vertical partition plates and transverse rib plates, and the reinforcing bars penetrate through the holes.

[0050] The support leg 22 is composed of a single steel pipe or two steel pipes. The two steel pipes are connected by two flat steel plates. Concrete is filled inside the steel pipes or vertical stiffening ribs are arranged inside the pipes. Bolt holes are arranged at the connection between the support leg 22 and the cantilever steel beam 21, and high-strength bolts are used to connect the support leg 22 and the cantilever steel beam 21.

[0051] Several inner ring beams 24 are arranged at the mid-span of the cantilever steel beam 21, and an outer ring beam 25 is arranged at the far end of the overhang. The inner ring beam 24 has an I-shaped, box-shaped, or channel-shaped cross-section, and the outer ring beam 25 has an I-shaped, box-shaped, or channel-shaped cross-section.

[0052] Holes are arranged at the connections between the inner ring beam 24, the outer ring beam 25 and the cantilever steel beam 21 for high-strength bolt connection.

[0053] Grooves for preventing the traction rope from slipping out are arranged on the outer side of the outer ring beam 25 and the outer side of the end of the cantilever steel beam 21.

[0054] Vertical reinforcing bars extend from the lower part of the bridge pier, and corresponding vertical reinforcing bars are arranged on the upper part of the bearing platform corresponding to the vertical reinforcing bars of the bridge pier. After the rotation is completed, the vertical reinforcing bars of the bridge pier and the bearing platform are connected.

[0055] A construction method for a rotating device of a solid-web cantilever steel beam in a rotating bridge specifically includes the following steps:

[0056] (1) Pile foundation construction: Drive the steel pipe piles for foundation pit protection around the foundation pit, excavate the space for the bearing platform downward according to the designed height, use a rotary drilling rig to excavate the pile holes, place the steel reinforcement cages, and pour the pile foundation concrete;

[0057] (2) First pouring of the bearing platform: After tying the steel bars of the bearing platform, conduct the first pouring of concrete for the bearing platform;

[0058] (3) Installation of the lower spherical hinge and slideway and second pouring of the bearing platform: After the concrete of the bearing platform reaches the specified strength, place the support steel frames for the slideway and spherical hinge, position the support steel frames for the slideway and spherical hinge, tie the steel bars of the lower bearing platform and the reaction seat, and then complete the second pouring of concrete for the bearing platform, and then carry out curing;

[0059] (4) Installation of the upper spherical hinge: Clean the sundries on the lower spherical hinge, then lay the polytetrafluoroethylene sliders, apply butter for lubrication, hoist the upper spherical hinge, and wind the tape at the gap of the spherical hinge to prevent sundries from entering;

[0060] (5) Installation of the temporary fixing device: Place the sand box at the designed position and set up the support frame for the steel sleeve;

[0061] (6) Installation of the steel sleeve, cantilever steel beam and support feet: Place the support feet on the slideway according to the specified position, hoist the cantilever steel beam, connect it to the steel sleeve steel formwork with high-strength bolts, insert a rubber pad between the cantilever steel beam and the support feet, finely adjust the gap, and then use bolts to connect the cantilever steel beam and the support feet;

[0062] (7) Splicing and installation of the cantilever steel beam and the inner and outer ring beams: After each cantilever steel beam is installed in place, use bolts to connect the cantilever steel beam and the inner and outer ring beams;

[0063] (8) Pier construction: Set up the pier formwork, tie the steel bars, check the stability of the support device and whether the bolts are loose, then pour the pier concrete. After the pier concrete reaches the strength requirement, remove the sand box and the steel sleeve support of the temporary fixing device at the bottom of the pier, and start the construction of the bridge deck structure;

[0064] (9) Main beam construction: Set up the formwork scaffolding for the main beam, set up the formwork, tie the steel bars, and then pour the main beam concrete;

[0065] (10) Installation of the traction cable: Install the traction rope at the outer anchorage of the outer ring beam and the cantilever steel beam, and pass the other end of the traction rope into the traction machines on both sides of the bearing platform;

[0066] (11) Swivel: Before swiveling, check again the bolt connection conditions at the node areas such as the steel sleeve, cantilever steel beam, inner and outer ring beams and support feet. After the swiveling starts, slowly tension the traction rope, and observe the readings of the pressure sensors between the cantilever steel beam and the support feet in real time. Adjust the counterweight in time when there is a large eccentricity;

[0067] (12) Casting of pedestal concrete: After the rotation is completed, connect the reinforcing bars between the lower part of the upper steel sleeve and the upper part of the lower bearing platform. Distribute the reinforcing bars along the periphery of the steel sleeve and weld them to the reserved reinforcing bars of the lower bearing platform. Set up the pedestal formwork and pour the concrete. After the concrete reaches the required strength, remove the cantilever steel beam and the support leg and recycle them.

[0068] (13) Removal of cantilever steel beam and support leg: After the bridge rotation is completed, first remove the cantilever steel beam and the inner and outer ring beams, and then remove the support leg and recycle it.

[0069] In the specific implementation of the present invention, the materials and types of the support device are improved, the production of the upper bearing platform is omitted, and at the same time, the support device is moved outwards, increasing the length of the lever arm, further improving the stability of the rotating structure; the solid-web cantilever steel beam is connected to the rotating bridge by a steel sleeve. The inner side of the steel sleeve is provided with rib plates, and the connection with the cantilever steel beam is provided with holes that can pass through bolts. The transverse direction of the cantilever steel beam realizes the overall effect through the inner and outer ring beams. The steel sleeve can be used as a formwork; when the bridge rotates, the steel strand is wound around the middle part of the outer side of the outer ring beam and the end of the cantilever steel beam to provide power for the rotating bridge; the structure is reasonably stressed, the construction is convenient, effectively reducing the volume of concrete pouring of the rotating structure, improving the stability of the rotating structure, and realizing the recyclability of part of the rotating structure, reflecting the concept of green and sustainable development of architecture, and being conducive to the innovation and development of bridge rotation projects.

[0070] In the existing rotation construction, since the support leg and the slideway occupy the space at the bottom of the bridge pier, a relatively large upper bearing platform needs to be made. The present invention can effectively reduce the concrete construction efficiency at the bottom of the bridge pier of the rotating device, be more economical and reliable, and at the same time expand the lever arm length of the support system, improving the stability of the rotating T-structure 11.

[0071] The advantages of the present invention include:

[0072] 1) The upper bearing platform of the rotating device can be cancelled, reducing the project quantity.

[0073] 2) The use of a steel structure support device can effectively improve the construction efficiency.

[0074] 3) The support device can be recycled and reused.

[0075] 4) The lever arm length of the bottom support device is increased, improving the overall stability.

[0076] The above describes the present invention and its implementation manners. Such a description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present invention, and the actual structure is not limited thereto. Generally speaking, if those of ordinary skill in the art are inspired by it and design similar structural manners and embodiments without creative work without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A rotating device for a solid-web cantilever steel beam in a swivel bridge. The rotating device is located at the bottom of the pier and includes a spherical hinge, a cantilever steel beam, a steel sleeve, a support foot, a slideway, an outer ring beam, an inner ring beam, and a traction cable. The spherical hinge includes an upper spherical hinge and a lower spherical hinge and is provided at the bottom of the pier or the top of the pile cap. The steel sleeve is provided at the lower part of the pier. The cantilever steel beams are arranged at intervals of 45°, 60°, or 90° along the outside of the pier. One end of the cantilever steel beam is fixed to the steel sleeve, and a support foot is fixed to the lower part of the other end of the cantilever steel beam. The traction cable is wound around the outside of the outer ring beam. The steel sleeve wraps around the outside of the pier. Vertical partition plates and transverse rib plates are provided inside the steel sleeve. End plates for connecting with the cantilever steel beam are provided on the outside of the steel sleeve. Holes are provided at the connection between the end plate of the steel sleeve and the cantilever steel beam for high-strength bolt connection. The cantilever steel beam has an I-shaped, box-shaped, or channel-shaped cross-section, and stiffening ribs are provided at the web of the cantilever steel beam. Holes with a size of 5 cm to 30 cm are provided in the vertical partition plates and transverse rib plates of the steel sleeve. Reinforcing bars are provided in the pier, and holes are provided at the intersections of the reinforcing bars with the vertical partition plates and transverse rib plates. The reinforcing bars penetrate through the holes. The support foot is composed of a single steel pipe or two steel pipes. The two steel pipes are connected by two flat steel plates. Concrete is filled in the steel pipes or vertical stiffening ribs are provided inside the pipes. Bolt holes are provided at the connection between the support foot and the cantilever steel beam, and high-strength bolts are used to connect the support foot and the cantilever steel beam. Several inner ring beams are provided at the mid-span of the cantilever steel beam, and an outer ring beam is provided at the far end of the overhang. The inner ring beam has an I-shaped, box-shaped, or channel-shaped cross-section, and the outer ring beam has an I-shaped, box-shaped, or channel-shaped cross-section. Holes are provided at the connections between the inner ring beam, the outer ring beam, and the cantilever steel beam for high-strength bolt connection. Grooves for preventing the traction rope from slipping out are provided on the outside of the outer ring beam and the outside of the end of the cantilever steel beam.

2. The swivel device of the solid-web cantilever steel beam in a swivel bridge according to claim 1, characterized in that: Vertical reinforcing bars extend from the lower part of the pier, and corresponding vertical reinforcing bars are provided on the upper part of the pile cap. After the rotation is completed, the vertical reinforcing bars of the pier and the pile cap are connected.

3. The construction method of a swivel device for a solid-web cantilever steel beam in a swivel bridge according to any one of claims 1-2, characterized in that, Specifically, it includes the following steps: (1) Pile foundation construction: Drive steel pipe piles for foundation pit protection around the foundation pit, excavate the pile cap space downward to the designed height, use a rotary drilling rig to excavate the pile hole, place the steel reinforcement cage, and pour pile foundation concrete. (2) First pouring of the pile cap: Bind the steel bars of the pile cap and then conduct the first pouring of concrete for the pile cap. (3) Installation of the lower spherical hinge, slideway, and second pouring of the pile cap: After the pile cap concrete reaches the specified strength, place the support steel frames of the slideway and the spherical hinge, position the support steel frames of the slideway and the spherical hinge, bind the steel bars of the lower pile cap and the reaction seat, and then complete the second pouring of concrete for the pile cap. After that, carry out curing. (4) Installation of the upper spherical hinge: Clean the debris on the lower spherical hinge, then lay polytetrafluoroethylene sliders, apply butter for lubrication, hoist the upper spherical hinge, and wind tape at the gaps of the spherical hinge to prevent foreign objects from entering. (5) Installation of the temporary fixing device: Place sand boxes at the designed positions and set up the support frame for the steel sleeve. (6) Installation of steel sleeve, cantilever steel beam and supporting feet: Place the supporting feet on the slideway according to the specified positions, hoist the cantilever steel beam, connect it to the steel sleeve formwork with high-strength bolts, insert rubber pads between the cantilever steel beam and the supporting feet, fine-tune the gap, and then connect the cantilever steel beam and the supporting feet with bolts; (7) Splicing and installation of cantilever steel beam and inner and outer ring beams: After each cantilever steel beam is installed in place, connect the cantilever steel beam to the inner and outer ring beams with bolts; (8) Pier construction: Set up pier formwork, tie steel bars, check the stability of the support device and whether the bolts are loose, then pour pier concrete. After the pier concrete reaches the strength requirement, remove the temporary fixing devices such as sand boxes and steel sleeve supports at the bottom of the pier and start the construction of the bridge deck structure; (9) Main beam construction: Set up the main beam formwork scaffolding, set up the formwork, tie steel bars, and then pour the main beam concrete; (10) Installation of traction cable: Install the traction rope at the outer anchorage of the outer ring beam and the cantilever steel beam, and pass the other end of the traction rope into the traction machines on both sides of the bearing platform; (11) Rotation: Before rotation, check again the bolt connection conditions of the steel sleeve, cantilever steel beam, inner and outer ring beams and the supporting foot node area. After the rotation starts, slowly tension the traction rope and observe the readings of the pressure sensors between the cantilever steel beam and the supporting feet in real time. Adjust the counterweight in time when there is a large eccentricity; (12) Casting of pedestal concrete: After the rotation is completed, weld the connecting steel bars at the lower part of the upper steel sleeve and the upper part of the lower bearing platform, arrange distribution steel bars along the periphery of the steel sleeve and weld them to the reserved steel bars of the lower bearing platform, set up the pedestal formwork and pour concrete. After the concrete reaches the strength requirement, remove the cantilever steel beam and the supporting feet and recycle them; (13) Removal of cantilever steel beam and supporting feet: After the bridge rotation is completed, first remove the cantilever steel beam and the inner and outer ring beams, and then remove the supporting feet and recycle them.

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