Method for assisting arch rib to turn over by utilizing winch and cable crane

Abstract

The invention relates to a method for assisting an arch rib to turn over by utilizing a winch and a cable crane, which belongs to the technical field of large-span bridge construction and is characterized in that three kinds of lifting points with complementary functions are accurately configured in a zoning manner through zoning optimization lifting point design, dynamic load distribution, hierarchical synchronous control and intelligent monitoring feedback according to the damage degree; pressure is transmitted along a main path of the gusset plate, bending moment is balanced by a sliding lifting point, tensile force is absorbed by concrete, an internal force closed loop is formed, and a tension-compression self-balancing system is formed; non-linear compensation of a sliding lifting point is achieved through a displacement-angle function, and geometric coordination of bending moment balance of a lower chord pipe and arch rib overturning is ensured; a three-stage hierarchical control strategy is adopted, reverse torque is triggered, the structural rigidity requirement of each stage is guaranteed, and sudden stress change is avoided; lossless conversion from a self-balancing system to a permanent structure is completed, and the problems that in the prior art, a lifting point arrangement mode not only causes the potential damage risk of the structure, but also causes the capacity redundancy of lifting equipment are systematically solved.

Description

Technical Field

[0001] The invention belongs to the technical field of large-span bridge construction, and in particular relates to a method for utilizing a winch and a cable hanger to assist in turning over an arch rib. Background Art

[0002] In the field of bridge construction, especially in the construction of large-span steel tube concrete arch bridges, the turning over of arch rib segments is a key link to ensure the precise installation of bridge structures. At present, in the existing technology, winches and cable cranes are used to assist in turning over arch ribs. When preparing for arch rib hoisting, the arch rib segments to be turned over are usually transported to the bottom of the cable hoisting point, and the hoisting stability is achieved by arranging fixed hoisting points on the arch rib upper chord tube.

[0003] However, with the increase of bridge span, the deadweight of arch rib increases significantly (usually reaching 200-400 tons), and the traditional hanging point arrangement method faces new technical challenges: on the one hand, during the dynamic lifting process of large-span arch rib, there are significant differences in stress distribution between the areas with high stiffness such as the node plate and diaphragm covering area, the arch foot reinforcement section, and the medium-strength areas such as the non-node area of ​​the lower chord, the transition section between the web and the chord, and the weak sections such as the upper chord in the mid-span, the free section of the cantilever end and the middle part of the steel pipe without diaphragm covering; on the other hand, the traditional hanging point arrangement does not fully consider the synergistic force characteristics of the steel pipe and concrete, especially the difference in the failure mechanism of local buckling of the steel pipe and cracking of the concrete during the lifting process, which is specifically manifested as follows: when the hanging points are concentrated on the upper chord, the upper chord in the mid-span is easy to be damaged. In the damage zone, the wall thickness of the steel pipe is usually only 20-30mm, which is prone to local buckling when subjected to dynamic bending moment; the radial stiffness of the steel pipe is reduced in the free section of the cantilever end due to the lack of diaphragm constraint; and the middle area of ​​the steel pipe without diaphragm coverage may cause the interface between the concrete and the steel pipe to peel off under the action of the lifting impact load. At the same time, although the difficult-to-destroy areas such as the node plate covering area, the diaphragm dense area and the arch foot reinforcement section have high bearing potential, they have not been effectively utilized. This traditional lifting point arrangement method not only causes potential structural damage risks, but also leads to redundant lifting equipment capacity, which seriously restricts the efficiency and economy of large-span arch rib lifting. Therefore, a method of using a winch and a cable hanger to assist the arch rib turning over is proposed. The self-balancing force in the lifting process is achieved through the coordinated use of the mechanical properties of each area. Summary of the invention

[0004] In order to solve the above-mentioned problems existing in the prior art, the present invention provides a method of using a winch and a cable hanger to assist in turning over the arch rib, which solves the problem that the arrangement of lifting points in the prior art not only causes potential structural damage risks, but also leads to redundant capacity of the lifting equipment, seriously restricting the lifting efficiency and economy of large-span arch ribs.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A method for assisting the turning over of arch ribs by using a hoist and a cable crane, comprising the following steps: S1: According to the difficulty of local buckling of steel pipes or cracking of concrete, the gusset plate, the diaphragm covering area and the arch foot strengthening section are defined as difficult-to-damage areas, the non-node area of the lower chord pipe and the connection transition section between the web member and the chord pipe are defined as medium-damage areas, and the upper chord pipe in the middle span, the free section of the cantilever end and the middle part of the steel pipe without diaphragm coverage are defined as easy-to-damage areas. Truss auxiliary lifting points are designed on the difficult-to-damage areas to transfer pressure, sliding auxiliary lifting points are designed on the medium-damage areas and balanced by the compression of the lower chord pipe, and anchoring auxiliary lifting points are designed on the easy-to-damage areas and the load is shared by the tension of the concrete, so as to form a tension-compression self-balancing system among the difficult-to-damage areas, the medium-damage areas and the easy-to-damage areas; S2: Establish a dynamic load distribution mechanism. The truss auxiliary lifting points bear part of the vertical load, and the main force transmission path is formed by using the compressive strength of the gusset plate area. The sliding auxiliary lifting points balance the bending moment through the axial compression of the lower chord pipe, and a functional relationship Δ = 0.15θ² is established between its sliding displacement Δ and the arch rib turning angle θ, where the unit of θ is radian; the anchoring auxiliary lifting points are used to utilize the tensile strength of the concrete to absorb the remaining tensile stress; S3: Control the synchronous operation of the double hoists in a hierarchical manner. The turning angle of 0-30° is defined as the initial stage, the turning angle of 30-60° is defined as the transition stage, and the turning angle of 60-90° is defined as the completion stage. In the initial stage, the hydraulic lock of the sliding auxiliary lifting point is locked to make the lower chord pipe form a continuous beam structure, and the load ratio of the truss auxiliary lifting point is increased. In the transition stage, the displacement constraint of the sliding saddle is gradually released. In the completion stage, the prestress compensation device of the anchoring auxiliary lifting point is activated. When the radial deformation of the upper chord pipe in the middle span exceeds 1 / 50 of the steel pipe diameter, a reverse torque is automatically applied; S4: After the arch rib is turned over to the designed configuration, the self-balanced state conversion is completed and the force system conversion is carried out; S5: Through intelligent monitoring and feedback adjustment until the entire hoisting process is completed.

[0006] As a further solution of the present invention, an H-shaped steel truss is longitudinally welded in the gusset plate covering area of the difficult-to-damage area to form a force transmission channel for the truss auxiliary lifting point, and its end is connected to the embedded steel plate of the arch foot strengthening section through high-strength bolts to transfer the hoisting pressure to the arch seat foundation.

[0007] As a further solution of the present invention, the cross-sectional height of the H-shaped steel truss in step S2 is 0.6-0.8 times the diameter of the chord pipe.

[0008] As a further solution of the present invention, the H-shaped steel truss forms an angle of 45° with the axis of the arch rib.

[0009] As a further solution of the present invention, a slidable saddle device is installed in the non-node area of the lower chord tube in the medium damage area, a polytetrafluoroethylene friction pair is arranged at the bottom of the saddle, and a pre-pressure is applied through a hydraulic jack to form a temporary consolidation between the sliding auxiliary lifting point and the chord tube.

[0010] As a further solution of the present invention, ribbed anchorages are implanted circumferentially in the upper chord tube at the mid-span of the easily damaged area, and the prestressed steel strands of the anchoring auxiliary lifting points penetrate through the steel tube wall to form a composite tensile system with the core concrete.

[0011] As a further solution of the present invention, the anchoring depth of the ribbed anchorage is greater than or equal to twice the wall thickness of the steel tube.

[0012] As a further solution of the present invention, step S5 further includes the following steps: S51: Filling the gap between the sliding saddle and the lower chord tube with high-strength grouting material to form a permanent consolidation; S52: Welding triangular stiffening plates between the truss auxiliary lifting points and the arch ribs to convert the temporary force transmission structure into a permanent strengthening structure; S53: Applying secondary tension to the steel strands of the anchoring auxiliary lifting points to increase the pre-compression stress of the concrete.

[0013] As a further solution of the present invention, a BIM dynamic control system is implanted in step S6, a preset value of the compressive stress in the gusset plate area and a preset value of the tensile stress in the concrete are preset in the control system, strain data of each area are collected every 15° of flipping angle, and when it is detected that the compressive stress in the gusset plate area exceeds the preset value or the tensile stress in the concrete exceeds the preset value, the lifting speed of the winch is automatically adjusted and reduced.

[0014] As a further solution of the present invention, in step S1, a carbon fiber grid reinforcement belt for stress transition is arranged at the junction of the easily damaged area and the medium damage area.

[0015] The beneficial effects of the present invention are: By optimizing the suspension point design, dynamic load distribution, hierarchical synchronous control, and intelligent monitoring feedback through zoning, S1 accurately configures three types of suspension points with complementary functions through damage degree zoning, enabling the pressure to be transmitted along the main path of the gusset plate, the moment to be balanced by the sliding suspension points, and the tension to be absorbed by the concrete, forming an internal force closed-loop and a tension-compression self-balancing system; S2 realizes the non-linear compensation of the sliding suspension points through the displacement-angle function of Δ = 0.15θ² to ensure the moment balance of the lower chord tube and the geometric coordination of the arch rib flipping; S3 adopts a three-stage hierarchical control strategy and combines a 1 / 50 diameter change threshold to trigger the reverse torque, which not only ensures the structural stiffness requirements at each stage but also avoids stress mutations; S4 completes the lossless conversion of the self-balancing system to the permanent structure, and S5 realizes closed-loop regulation through real-time monitoring, not only reducing the hoisting damage rate but also reducing the investment in lifting equipment. Through the precise matching of mechanical properties and construction phases, the hoisting efficiency of the long-span arch rib is improved, systematically solving the problems in the prior art that the suspension point arrangement method not only causes potential structural damage risks but also leads to redundant lifting equipment capabilities, severely restricting the hoisting efficiency and economy of the long-span arch rib. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] For the convenience of those skilled in the art to understand, the present invention will be further described below with reference to the accompanying drawings.

[0017] Figure 1 It is a flowchart of the method for using a winch and a cable crane to assist the arch rib to turn over according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following will describe in detail the specific embodiments, structures, features, and effects of the present invention with reference to the accompanying drawings and preferred embodiments.

[0019] Please refer to Figure 1 , this embodiment provides a method for using a winch and a cable crane to assist the arch rib to turn over, including the following steps: S1: According to the difficulty of local buckling of steel pipes or cracking of concrete, the covered areas of gusset plates, diaphragms, and the arch foot strengthening sections are designated as difficult-to-damage areas, the non-node areas of the lower chord pipes and the transition sections where the web members are connected to the chord pipes are designated as moderately-damaged areas, and the upper chord pipes in the middle of the span, the free sections at the cantilever ends, and the middle parts of the steel pipes without diaphragm coverage are designated as easy-to-damage areas. Truss auxiliary lifting points are designed on the difficult-to-damage areas to transfer pressure, sliding auxiliary lifting points are designed on the moderately-damaged areas and balanced by the compression of the lower chord pipes, and anchoring auxiliary lifting points are designed on the easy-to-damage areas and the tensile force of the concrete is used to share the load, so as to form a tensile-compressive self-balanced system among the difficult-to-damage areas, moderately-damaged areas, and easy-to-damage areas; a carbon fiber grid reinforcement belt for stress transition is set at the junction between the easy-to-damage area and the moderately-damaged area; here, by classifying the difficulty of damage in different areas and designing corresponding auxiliary lifting points, the load can be effectively distributed on the strong and weak points of the structure, avoiding local damage caused by load concentration; S2: Establish a dynamic load distribution mechanism. The truss auxiliary lifting points bear part of the vertical load, and the main force transmission path is formed by using the compressive strength of the gusset plate area. The sliding auxiliary lifting points balance the bending moment through the axial compression of the lower chord pipe. A functional relationship Δ = 0.15θ² is established between its sliding displacement Δ and the arch rib flipping angle θ, where the unit of θ is radian; the anchoring auxiliary lifting points are used to utilize the tensile strength of the concrete to absorb the remaining tensile stress; establishing a dynamic load distribution mechanism can ensure that during the flipping process of the arch rib, the load can be dynamically adjusted according to the deformation and position of the arch rib, maintaining the stability of the structure; Combining S1 - S2, the self-balancing principle here is the mechanical complementarity adopted according to the force analysis. The vertical load is converted into axial pressure through the truss and transmitted to the foundation, which can be understood as the pressure path. The anchoring lifting points disperse the tensile stress to the concrete through the steel strands, which can be understood as the pressure path. The sliding saddle is compressed to offset the tensile bending effect of the upper chord pipe in the middle of the span, which can be understood as the bending moment balance; the sliding displacement Δ is adjusted according to the flipping angle θ to make the pressure and tensile force match in real time, realizing the internal force redistribution, which is the dynamic adjustment; S3: The synchronous operation of the double winches is controlled in a hierarchical manner. The flipping angle of 0 - 30° is designated as the initial stage, the flipping angle of 30 - 60° is designated as the transition stage, and the flipping angle of 60 - 90° is designated as the completion stage. In the initial stage, the hydraulic lock for locking the sliding auxiliary lifting points is used to make the lower chord pipe form a continuous beam structure and increase the load ratio of the truss auxiliary lifting points. In the transition stage, the displacement constraint of the sliding saddle is gradually released. In the completion stage, the prestress compensation device of the anchoring auxiliary lifting points is activated. When it is detected that the radial deformation of the upper chord pipe in the middle of the span exceeds 1 / 50 of the steel pipe diameter, a force is automatically applied for reverse torque; controlling the flipping process in a hierarchical manner can make targeted adjustments according to the force characteristics of the arch rib in different stages, ensuring the smoothness and controllability of the entire flipping process; hierarchical control helps to reduce the structural damage caused by too fast or too slow flipping. By adopting different control strategies in different stages, the accuracy and efficiency of the hoisting are improved; S4: After the arch rib is flipped to the designed configuration, the self - balance state conversion is completed, and the force - bearing system conversion is carried out. Completing the self - balance state conversion and the force - bearing system conversion is to ensure that the structure can stably bear the subsequent loads after the arch rib is flipped in place, ensuring the stability of the structure after it is flipped in place and preventing structural instability caused by the failure to convert the force - bearing system. S5: Through intelligent monitoring and feedback regulation until the entire hoisting process is completed. Adopting intelligent monitoring and feedback regulation can timely grasp the structural state during the hoisting process, adjust the hoisting parameters in a timely manner, and ensure the smooth progress of the hoisting process.

[0020] At present, with the increase of the bridge span, the self - weight of the arch rib increases significantly, and the traditional suspension point arrangement method faces new technical challenges: on the one hand, during the dynamic hoisting process of the long - span arch rib, there are significant differences in stress distribution between areas with high stiffness such as the covered area of the gusset plate and diaphragm, the arch - foot strengthening section, medium - strength areas such as the non - node area of the lower chord tube, the connection transition section between the web member and the chord tube, and weak sections such as the upper chord tube in the middle of the span, the free section of the cantilever end, and the middle part of the steel pipe without diaphragm coverage; on the other hand, the traditional suspension point arrangement does not fully consider the cooperative force - bearing characteristics of the steel pipe and concrete, especially the difference in the failure mechanism of local buckling of the steel pipe and concrete cracking during the hoisting process. Specifically, when the suspension points are concentrated on the upper chord tube, the upper chord tube in the middle of the span, as an easily damaged area, usually has a steel pipe wall thickness of only 20 - 30 mm and is prone to local buckling when bearing dynamic bending moments; the free section of the cantilever end has a reduced radial stiffness of the steel pipe due to the lack of diaphragm constraints; in the middle area of the steel pipe without diaphragm coverage, the interface peeling between the concrete and the steel pipe may be caused under the action of the hoisting impact load. At the same time, although the difficult - to - damage areas such as the covered area of the gusset plate, the diaphragm - dense area, and the arch - foot strengthening section have high load - bearing potential, they are not effectively utilized. This traditional suspension point arrangement method not only causes potential damage risks to the structure but also leads to redundant capacity of the hoisting equipment, seriously restricting the hoisting efficiency and economy of the long - span arch rib.

[0021] To solve the above problems, in this embodiment, through zonal optimization of the suspension point design, dynamic load distribution, hierarchical synchronous control, and intelligent monitoring feedback, S1 accurately configures three types of complementary - function suspension points through damage - degree zoning, enabling the pressure to be transmitted along the main path of the gusset plate, the bending moment to be balanced by the sliding suspension points, and the tensile force to be absorbed by the concrete, forming an internal - force closed - loop and a tension - compression self - balance system; S2 realizes the non - linear compensation of the sliding suspension points through the displacement - angle function of Δ = 0.15θ² to ensure the bending - moment balance of the lower chord tube and the geometric coordination of the arch - rib flipping; S3 adopts a three - stage hierarchical control strategy, combined with a 1 / 50 diameter - change threshold to trigger the reverse torque, which not only ensures the structural stiffness requirements at each stage but also avoids stress mutations; S4 completes the lossless conversion of the self - balance system to the permanent structure, and S5 realizes closed - loop regulation through real - time monitoring. It not only reduces the hoisting damage rate, but also reduces the investment in hoisting equipment. By precisely matching the mechanical properties and construction phases, the hoisting efficiency of long-span arch ribs is improved, systematically solving the problems in the prior art that the existing hoisting point arrangement method not only causes potential structural damage risks, but also leads to redundant hoisting equipment capacity, severely restricting the hoisting efficiency and economy of long-span arch ribs.

[0022] The traditional method usually adopts vertical force transmission. In the vertical force transmission method, the force mainly transmits along the axis of the beam-column. However, when the structure is subjected to external loads, due to factors such as the geometric shape, connection method or material properties of the gusset plate, the force distribution is not always uniform. This non-uniform force distribution will generate local stress concentration near the gusset plate, resulting in the generation of additional bending moments. To avoid this problem, in one embodiment, an H-shaped steel truss is longitudinally welded in the gusset plate covering area of the difficult-to-damage area to form a truss-assisted hoisting point force transmission channel. Its end is connected to the embedded steel plate of the arch foot strengthening section through high-strength bolts to transmit the hoisting pressure to the arch seat foundation. The H-shaped steel truss transmits the concentrated load to the arch seat foundation, reducing the local compressive stress of the gusset plate and dispersing the pressure accordingly; the section height of the H-shaped steel truss is 0.6 - 0.8 times the diameter of the chord tube to ensure stiffness matching with the arch rib and avoid deformation mismatch; the high-strength bolt connection is convenient for demolition after construction, reducing permanent structure damage. The H-shaped steel truss forms a 45° angle with the axis of the arch rib, and the 45° force transmission angle enables the load to be transmitted to the core area of the gusset plate in the form of pure compression, avoiding additional bending moments.

[0023] Since it is a long-span arch rib, during the hoisting process, the dynamic loads exerted by the slings and lifting appliances on the lower chord tube will cause the structure to vibrate, thus increasing the risk of compressive buckling. The risk of micro-movement and interface slippage that may occur during the hoisting process is relatively high. In addition, due to excessive constraint stress in local areas, local buckling may occur, further affecting the stability of the entire structure. To solve this problem, in one embodiment, a slidable saddle device is installed in the non-node area of the lower chord tube in the medium-damage area. This device can provide necessary support during the hoisting process and at the same time allow a certain amount of sliding to release part of the constraint stress. The slidable saddle device here includes a saddle main body and a sliding component, where the sliding component can be a pulley or a slider. A polytetrafluoroethylene friction pair is arranged at the bottom of the saddle, and a pre-pressure is applied through a hydraulic jack to form a temporary consolidation between the sliding auxiliary hoisting point and the chord tube. Because the polytetrafluoroethylene friction coefficient μ ≤ 0.1, using polytetrafluoroethylene can reduce the sliding resistance and avoid damage to the steel pipe surface. The sliding design can release the constraint stress and prevent local buckling. By applying a pre-pressure through a hydraulic jack to form a temporary consolidation between the sliding auxiliary hoisting point and the chord tube, this helps to improve the overall stability of the structure.

[0024] In addition, during the construction of long-span arch ribs, since the concrete cannot participate in bearing when the upper chord pipe in the middle of the span is in tension, it is easy to cause the steel pipe to be overstressed alone, which affects the turning over of the arch rib. To better avoid this problem, in one embodiment, ribbed anchor bolts are implanted circumferentially in the upper chord pipe in the middle of the span in the vulnerable area. The prestressed steel strands of the anchoring auxiliary lifting points penetrate the steel pipe wall to form a composite tension-bearing system with the core concrete. The anchoring depth of the ribbed anchor bolts is greater than or equal to twice the wall thickness of the steel pipe. The tension is transmitted to the concrete through the steel strands, reducing the peak stress of the steel pipe. The ribbed design improves the uplift resistance of the anchor bolts and prevents interface peeling. The anchoring depth of the ribbed anchor bolts being greater than or equal to twice the wall thickness of the steel pipe may directly weld the lifting points, which is prone to buckling. The anchor bolts activate the tensile capacity of the concrete through prestress.

[0025] Furthermore, for long-span arch ribs, to further ensure the safety and stability during the turning over process of the structure, as well as the long-term stability and bearing capacity of the structure after completion, in one embodiment, step S5 further includes the following steps: S51: Fill the gap between the sliding saddle and the lower chord pipe with high-strength grouting material to form a permanent consolidation; filling the gap with high-strength grouting material can prevent local stress concentration or structural instability caused by the gap during the turning over process. The consolidated structure can reduce the vibration that may occur during the hoisting process and reduce the wear caused by vibration; S52: Weld triangular stiffening plates between the truss auxiliary lifting points and the arch rib to transform the temporary force transfer structure into a permanent strengthening structure; the triangular stiffening plates can provide additional structural strength, especially for structures like arch ribs that need to bear large pressures. By welding the stiffening plates, the connection performance between the truss and the arch rib can be improved, the overall structural stability can be enhanced, and the temporary force transfer structure can be transformed into a permanent strengthening structure, which is beneficial for the long-term use of the structure; S53: Apply secondary tension to the steel strands of the anchoring auxiliary lifting points to increase the precompression stress of the concrete. Applying secondary tension is to further increase the precompression stress of the concrete, enhance the bearing capacity and stability of the structure. By tensioning the steel strands, the stress distribution inside the structure can be adjusted to make it more reasonable, thereby extending the service life of the structure. The increase in precompression stress helps reduce the cracks generated in the concrete during the service process due to the action of loads.

[0026] Furthermore, to better ensure the stability and safety of the entire turning-over process, in one embodiment, a BIM dynamic control system is implanted in step S6. The preset values of the compressive stress in the gusset plate area and the tensile stress of the concrete are preset in the control system. By collecting the strain data of each area every 15° of turning angle, stress changes can be detected in a timely manner and corresponding adjustments can be made. When it is detected that the compressive stress in the gusset plate area exceeds the preset value or the tensile stress of the concrete exceeds the preset value, the hoist lifting speed is automatically adjusted to decrease. The preset values of the compressive stress in the gusset plate area and the tensile stress of the concrete are to ensure that the structure will not be damaged due to excessive stress during the turning-over process. When the monitored stress exceeds the preset value, the hoist lifting speed is automatically decreased, which can effectively control the stress within a safe range. During the turning-over process, if the stress exceeds the bearing capacity of the material, it may cause structural damage or even failure. Through real-time monitoring and adjustment, this situation can be prevented.

[0027] As described above, it is only a preferred embodiment of the present invention and does not impose any form of limitation on the present invention. Although the present invention has been disclosed as above with the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments with equivalent changes within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for assisting the turning over of an arch rib by using a winch and a cable hanger, characterized in that: The following steps are involved: S1: According to the difficulty of local buckling of steel tubes or cracking of concrete, the node plate, diaphragm covering area and arch foot reinforcement section are defined as difficult-to-destroy areas, the non-node area of ​​the lower chord tube and the transition section between the web member and the chord tube are defined as medium-destroy areas, the upper chord tube in the middle of the span, the free section of the cantilever end and the middle part of the steel tube without diaphragm covering are defined as easy-to-destroy areas, and truss auxiliary hanging points are designed on the difficult-to-destroy areas to transmit pressure, sliding auxiliary hanging points are designed on the medium-destroy areas to balance the pressure through the lower chord tube, and anchor auxiliary hanging points are designed on the easy-to-destroy areas to share the load through the concrete tension, so that a tension-compression self-balancing system is formed among the difficult-to-destroy areas, medium-destroy areas and easy-to-destroy areas; S2: Establish a dynamic load distribution mechanism. The auxiliary truss hanging points bear part of the vertical load. The compressive strength of the node plate area is used to form the main force transmission path. The sliding auxiliary hanging points balance the bending moment through the axial compression of the lower chord tube. The sliding displacement Δ and the arch rib flip angle θ establish a functional relationship Δ=0.15θ², where θ is in radians. The anchor auxiliary hanging points are used to exert the tensile strength of the concrete to absorb the remaining tensile stress. S3: A hierarchical method is used to control the synchronous operation of the dual winches, with a flip angle of 0-30° as the initial stage, a flip angle of 30-60° as the transition stage, and a flip angle of 60-90° as the completion stage. In the initial stage, the hydraulic lock of the sliding auxiliary hanging point is used to lock the lower chord tube to form a continuous beam structure, increase the load proportion of the truss auxiliary hanging point, gradually release the displacement constraint of the sliding saddle in the transition stage, and activate the prestressed compensation device of the anchor auxiliary hanging point in the completion stage. When the radial deformation of the upper chord tube in the mid-span exceeds 1 / 50 of the steel tube diameter, force is automatically applied to perform reverse torque; S4: After the arch rib is flipped to the designed position, the self-balanced state conversion is completed and the force system conversion is carried out; S5: Through intelligent monitoring and feedback adjustment, the entire lifting process is completed.

2. A method for assisting arch rib turning over by using a winch and a cable hanger according to claim 1, characterized in that: An H-shaped steel truss is longitudinally welded in the node plate covering area of ​​the difficult-to-destroy area to form a truss auxiliary lifting point force transmission channel, the end of which is connected to the embedded steel plate of the arch foot reinforcement section through high-strength bolts to transmit the lifting pressure to the arch seat foundation.

3. The method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 2, characterized in that: In step S2, the cross-sectional height of the H-shaped steel truss is 0.6-0.8 times the diameter of the chord tube.

4. The method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 2, characterized in that: The H-shaped steel truss forms an angle of 45° with the axis of the arch rib.

5. The method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 1, characterized in that: A slidable saddle device is installed in the non-node area of ​​the lower chord tube in the medium damage zone, a polytetrafluoroethylene friction pair is arranged at the bottom of the saddle, and pre-pressure is applied by a hydraulic jack to temporarily consolidate the sliding auxiliary hanging point and the chord tube.

6. The method of using a winch and a cable hanger to assist the arch rib turning over according to claim 1, characterized in that: A ribbed anchor is circumferentially implanted in the upper chord tube at the mid-span of the vulnerable zone, and the prestressed steel strands of the anchor auxiliary hanging points penetrate the steel tube wall and the core concrete to form a composite tension system.

7. A method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 6, characterized in that: The anchoring depth of the ribbed anchor is greater than or equal to twice the wall thickness of the steel pipe.

8. The method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 1, characterized in that: The step S5 further comprises the following steps: S51: Fill the gap between the sliding saddle and the lower chord tube with high-strength grouting material to form permanent consolidation; S52: Weld triangular stiffening plates between the auxiliary truss hanging points and the arch ribs to transform the temporary force transmission structure into a permanent reinforcement structure; S53: Secondary tension is applied by anchoring the steel strands at the auxiliary hanging points to increase the pre-compression stress of the concrete.

9. The method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 1, characterized in that: In step S6, a BIM dynamic control system is implanted, and a preset value of the compressive stress in the node plate area and a preset value of the tensile stress in the concrete are preset in the control system. The strain data of each area is collected once every 15° flip angle. When it is detected that the compressive stress in the node plate area exceeds the preset value or the tensile stress in the concrete exceeds the preset value, the hoisting speed of the winch is automatically adjusted to be reduced.

10. The method of using a winch and a cable hanger to assist the turning of an arch rib according to claim 1, characterized in that: In the step S1, a carbon fiber grid reinforcement belt for transitional stress is arranged at the junction of the easily damaged area and the medium damaged area.

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