A method for assisting the turning over of arch ribs by using a winch and a cable crane

Abstract

The present invention relates to a method for assisting the turning over of arch ribs by using a hoist and a cable crane, belonging to the technical field of long-span bridge construction. Through the partition optimization of the lifting point design, dynamic load distribution, hierarchical synchronous control and intelligent monitoring feedback, three types of lifting points with complementary functions are accurately configured according to the damage degree partition, so that the pressure is transmitted along the main path of the gusset plate, the bending moment is balanced by the sliding lifting points, and the tension is absorbed by the concrete, forming an internal force closed loop and a tension-compression self-balanced system; the nonlinear compensation of the sliding lifting points is realized through the displacement-angle function to ensure the bending moment balance of the lower chord pipe and the geometric coordination of the arch rib turning; a three-stage hierarchical control strategy is adopted to trigger the reverse torque, which not only ensures the structural stiffness requirements in each stage but also avoids stress mutation; the lossless conversion of the self-balanced system to the permanent structure is completed, systematically solving the problems in the prior art that the lifting point arrangement method not only causes potential damage risks to the structure but also leads to redundant lifting equipment capabilities.

Description

Technical Field

[0001] The invention belongs to the technical field of long-span bridge construction, and particularly relates to a method for assisting arch rib turning by utilizing a winch and a cable crane. 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 the turning over of arch ribs. When preparing for the 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 ribs increases significantly (usually reaching 200-400 tons), and the traditional lifting point arrangement method faces new technical challenges: on the one hand, during the dynamic lifting process of large-span arch ribs, 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 tube, the transition section between the web and the chord tube, and the 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 tube without diaphragm covering; on the other hand, the traditional lifting point arrangement does not fully consider the coordinated stress characteristics of steel tubes and concrete, especially the difference in the failure mechanism of local buckling of steel tubes and cracking of concrete during lifting, which is specifically manifested as follows: when the lifting points are concentrated on the upper chord tube, the upper chord tube in the middle of the span is easy to 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 free section of the cantilever end lacks diaphragm constraint, resulting in reduced radial stiffness of the steel pipe; and the middle area of the steel pipe without diaphragm coverage may cause interface peeling between the concrete and the steel pipe under the action of lifting impact load. At the same time, although the difficult-to-destroy areas such as the node plate coverage area, the diaphragm dense area and the arch foot reinforcement section have high bearing potential, they are not effectively utilized. This traditional lifting point arrangement method not only creates potential structural damage risks, but also leads to redundant lifting equipment capacity, seriously restricting the efficiency and economy of long-span arch rib lifting. Therefore, a method of using a winch and a cable crane to assist in the arch rib turning over is proposed. By synergistically utilizing the mechanical properties of each area, self-balancing force during the lifting process is achieved. 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 crane to assist in turning over the arch rib, which solves the problem that the arrangement of lifting points in the prior art not only creates a potential risk of structural damage, but also leads to redundant capacity of the lifting equipment, seriously restricting the efficiency and economy of lifting large-span arch ribs.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A method for assisting the turning over of arch ribs by using a hoist and a cable crane, comprising the following steps:

[0007] S1: According to the difficulty of local buckling of steel pipes or concrete cracking, demarcate the gusset plate, the covered area of diaphragms and the arch foot strengthening section as difficult-to-damage areas, demarcate the non-node area of the lower chord pipe and the connection transition section between the web members and the chord pipes as medium-damage areas, and demarcate the upper chord pipe in the middle span, the free section at the cantilever end and the middle part of the steel pipe without diaphragm coverage as easy-to-damage areas. Design truss auxiliary lifting points on the difficult-to-damage areas to transfer pressure, design sliding auxiliary lifting points on the medium-damage areas and balance them through the compression of the lower chord pipe, and design anchoring auxiliary lifting points on the easy-to-damage areas and share the load through the tension of concrete, so as to form a tensile-compressive self-balanced system among the difficult-to-damage areas, the medium-damage areas and the easy-to-damage areas;

[0008] S2: Establish a dynamic load distribution mechanism. The truss auxiliary lifting points bear part of the vertical load, use the compressive strength in the gusset plate area to form the main force transmission path, the sliding auxiliary lifting points balance the bending moment through the axial compression of the lower chord pipe, and establish a functional relationship between the sliding displacement Δ and the turning angle θ of the arch rib as Δ = 0.15θ², where the unit of θ is radian; utilize the anchoring auxiliary lifting points to exert the tensile strength of concrete to absorb the remaining tensile stress;

[0009] S3: Control the synchronous operation of the double hoists in a hierarchical manner. Demarcate the turning angle of 0 - 30° as the initial stage, the turning angle of 30 - 60° as the transition stage, and the turning angle of 60 - 90° as the completion stage.

[0010] In the initial stage, lock the hydraulic lock of the sliding auxiliary lifting points to make the lower chord pipe form a continuous beam structure, increase the load proportion of the truss auxiliary lifting points, gradually release the displacement constraint of the sliding saddle seat in the transition stage, activate the prestress compensation device of the anchoring auxiliary lifting points in the completion stage, and automatically apply a force for reverse torque when it is detected that the radial deformation of the upper chord pipe in the middle span exceeds 1 / 50 of the steel pipe diameter;

[0011] S4: After the arch rib is turned over to the designed configuration, complete the conversion of the self-balanced state and conduct the conversion of the force system;

[0012] S5: Through intelligent monitoring and feedback regulation until the entire hoisting process is completed.

[0013] As a further solution of the present invention, longitudinally weld an H-shaped steel truss in the covered area of the gusset plate in the difficult-to-damage area to form a force transmission channel for the truss auxiliary lifting points, and connect its end 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.

[0014] As a further solution of the present invention, the section height of the H-shaped steel truss is 0.6 - 0.8 times the diameter of the chord pipe.

[0015] As a further solution of the present invention, the H-shaped steel truss forms an angle of 45° with the arch rib axis.

[0016] As a further solution of the present invention, a sliding saddle device is installed in the non-node area of the lower chord tube in the medium damage zone, a polytetrafluoroethylene friction pair is set at the bottom of the saddle, and pre-pressure is applied by a hydraulic jack to temporarily consolidate the sliding auxiliary lifting point and the chord tube.

[0017] As a further solution of the present invention, ribbed anchors are circumferentially implanted into the upper chord tube in the mid-span of the vulnerable area, and the prestressed steel strands anchoring the auxiliary hanging points penetrate the steel tube wall and the core concrete to form a composite tension system.

[0018] As a further solution of the present invention, the anchoring depth of the ribbed anchor is greater than or equal to twice the wall thickness of the steel pipe.

[0019] As a further solution of the present invention, step S5 further includes the following steps:

[0020] S51: Fill the gap between the sliding saddle and the lower chord tube with high-strength grouting material to form permanent consolidation;

[0021] S52: Weld triangular stiffening plates between the truss auxiliary hanging points and the arch ribs to transform the temporary load-transmitting structure into a permanent reinforcement structure;

[0022] S53: Secondary tension is applied by anchoring the steel strands at the auxiliary lifting points to increase the pre-compression stress of the concrete.

[0023] As a further solution of the present invention, a BIM dynamic control system is implanted in step S5, and a preset value of the compressive stress of the node plate area and a preset value of the tensile stress of 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 of the node plate area exceeds the preset value or the tensile stress of the concrete exceeds the preset value, the hoisting speed of the winch is automatically adjusted to be reduced.

[0024] As a further solution of the present invention, in step S1, a carbon fiber grid reinforcement belt for transitional stress is provided at the junction of the easily damaged area and the medium damaged area.

[0025] The beneficial effects of the present invention are:

[0026] By optimizing the suspension point design, dynamic load distribution, hierarchical synchronous control, and intelligent monitoring feedback through zoning, S1 accurately configures three types of complementary 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-balanced system; S2 realizes the non-linear compensation of the sliding suspension points through the displacement-angle function of Δ = 0.15θ², ensuring 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 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-balanced 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. By precisely matching the 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 damage risks to the structure 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

[0027] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with the accompanying drawings.

[0028] Figure 1 It is a flowchart of the method for using a winch and a cable crane to assist the arch rib in turning over according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] 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 in conjunction with the accompanying drawings and preferred embodiments.

[0030] Please refer to Figure 1 , this embodiment provides a method for using a winch and a cable crane to assist the arch rib in turning over, including the following steps:

[0031] S1: According to the difficulty of local buckling of steel pipes or cracking of concrete, demarcate the gusset plate, the covered area of diaphragms and the arch foot strengthening section as difficult-to-damage areas, demarcate the non-node area of the lower chord pipe and the connection transition section between the web members and the chord pipes as medium-damage areas, and demarcate the upper chord pipe in the middle of the span, the free section at the cantilever end and the middle part of the steel pipe without diaphragm coverage as easy-to-damage areas. Design truss auxiliary lifting points on the difficult-to-damage areas to transfer pressure, design sliding auxiliary lifting points on the medium-damage areas and balance them through the compression of the lower chord pipe, and design anchoring auxiliary lifting points on the easy-to-damage areas and share the load through the tension of concrete, so as to form a tensile-compressive self-balancing system among the difficult-to-damage areas, medium-damage areas and easy-to-damage areas; Set a carbon fiber grid reinforcement belt for stress transition at the junction of the easy-to-damage area and the medium-damage 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;

[0032] S2: Establish a dynamic load distribution mechanism. The truss auxiliary lifting points bear part of the vertical load, and use the compressive strength of the gusset plate area to form the main force transmission path. The sliding auxiliary lifting points balance the moment through the axial compression of the lower chord pipe. The function relationship between its sliding displacement Δ and the arch rib flipping angle θ is Δ = 0.15θ², where the unit of θ is radian; Use the anchoring auxiliary lifting points to exert the tensile strength of 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;

[0033] 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 moment balance; Adjust the sliding displacement Δ according to the flipping angle θ to make the pressure and tension match in real time, realizing the internal force redistribution, which is the dynamic adjustment;

[0034] S3: Control the synchronous operation of the double hoist in a hierarchical manner. Define the tipping angle of 0 - 30° as the initial stage, the tipping angle of 30 - 60° as the transition stage, and the tipping angle of 60 - 90° as the completion stage. In the initial stage, use a locking sliding auxiliary lifting point hydraulic lock to form a continuous beam structure for the lower chord tube, increasing the load ratio of the truss auxiliary lifting point. In the transition stage, gradually release the displacement constraint of the sliding saddle. In the completion stage, activate the prestressed compensation device for the anchoring auxiliary lifting point. When it is detected that the radial deformation of the upper chord tube at the mid-span exceeds 1 / 50 of the steel pipe diameter, automatically apply force for reverse torque. By adopting hierarchical control of the tipping process, targeted adjustments can be made according to the force characteristics of different stages of the arch rib, ensuring the smoothness and controllability of the entire tipping process. Hierarchical control helps reduce structural damage caused by too fast or too slow tipping. By adopting different control strategies at different stages, the accuracy and efficiency of hoisting are improved.

[0035] S4: After the arch rib is tipped to the designed configuration, complete the self-balanced state conversion and conduct the force system conversion. Completing the self-balanced state conversion and the force system conversion is to ensure that the structure can stably bear the subsequent loads after the arch rib is tipped in place, ensuring the stability of the structure after tipping and preventing structural instability caused by the failure to convert the force system.

[0036] S5: Through intelligent monitoring and feedback regulation until the entire hoisting process is completed. Adopting intelligent monitoring and feedback regulation can timely master the structural state during the hoisting process, adjust the hoisting parameters in a timely manner, and ensure the smooth progress of the hoisting process.

[0037] At present, with the increase of bridge span, the deadweight of arch rib increases significantly, and the traditional lifting 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 tube, the transition section between the web and the chord tube, and the 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 tube without diaphragm covering; on the other hand, the traditional lifting point arrangement does not fully consider the coordinated stress characteristics of steel tube and concrete, especially the difference in the failure mechanism of local buckling of steel tube and cracking of concrete during the lifting process, which is specifically manifested as follows: when lifting, the steel tube is bent and the concrete is deformed, and the steel tube is pulled out of the way. When the lifting points are concentrated on the upper chord tube, the mid-span upper chord tube is a vulnerable area, and its steel tube wall thickness is usually only 20-30mm, which is prone to local buckling when subjected to dynamic bending moment; the free section of the cantilever end lacks diaphragm constraints, resulting in reduced radial stiffness of the steel tube; and the middle area of the steel tube without diaphragm coverage may cause interface peeling between concrete and steel tube under the action of lifting impact load. At the same time, although the difficult-to-destroy areas such as the node plate coverage area, the diaphragm dense area and the arch foot reinforcement section have high bearing potential, they are not effectively utilized. This traditional lifting point arrangement method not only creates potential structural damage risks, but also leads to redundant lifting equipment capacity, seriously restricting the efficiency and economy of large-span arch rib lifting.

[0038] To address the above issues, in this embodiment, through zoning optimization of hanging point design, dynamic load distribution, hierarchical synchronous control, and intelligent monitoring feedback, S1 precisely configures three types of hanging points with complementary functions based on damage degree zoning, so that pressure is transmitted along the main path of the node plate, bending moment is balanced by the sliding hanging points, and tension is absorbed by the concrete, forming an internal force closed loop and a tension-compression self-balancing system. S2 implements nonlinear compensation of the sliding hanging points through a displacement-angle function of Δ=0.15θ², ensuring geometric coordination between the bending moment balance of the lower chord tube and the flipping of the arch rib. S3 adopts a three-stage hierarchical control strategy, combined with a 1 / 50 diameter change threshold to trigger reverse torque, which not only meets the structural stiffness requirements at each stage but also avoids stress mutations. S4 completes the lossless conversion of the self-balancing system to a permanent structure, and S5 implements closed-loop control through real-time monitoring.

[0039] It not only reduces the lifting damage rate but also reduces the investment in lifting equipment. Through the precise matching of mechanical properties and construction phases, the lifting efficiency of large-span arch ribs is improved. It systematically solves the problem that the lifting point arrangement method in the existing technology 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.

[0040] The traditional method is usually to use vertical force transmission. In the vertical force transmission method, the force is mainly transmitted along the axis of the beam column. However, when the structure is subjected to external loads, the force distribution is not always uniform due to factors such as the geometry of the node plate, the connection method or the material properties. This uneven force distribution will cause local stress concentration near the node plate, thereby causing additional bending moment. In order to avoid this problem, in one embodiment, H-shaped steel trusses are 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 ends are connected to the embedded steel plates of the arch foot reinforcement section through high-strength bolts to transfer the lifting pressure to the arch seat foundation. The H-shaped steel truss transfers the concentrated load to the arch seat foundation, reducing the local compressive stress of the node plate and thus dispersing the pressure. The cross-sectional height of the H-shaped steel truss is 0.6-0.8 times the diameter of the chord tube to ensure that it matches the stiffness of the arch rib and avoid deformation mismatch. The high-strength bolt connection facilitates dismantling after construction and reduces permanent structural damage. The H-shaped steel truss forms a 45° angle with the arch rib axis. The 45° force transmission angle allows the load to be transferred to the core area of the node plate in the form of pure compression, avoiding additional bending moment.

[0041] Due to the large span of the arch rib, the dynamic loads imposed on the lower chord by the slings and slings during the hoisting process can cause structural vibration, thereby increasing the risk of compressive instability. Furthermore, the risk of micro-motion and interface slippage that may occur during the hoisting process is high. Furthermore, excessive restraint stress in localized areas can cause local buckling, which in turn affects the stability of the entire structure. To address this issue, in one embodiment, a sliding saddle device is installed in the non-node area of the lower chord in the medium damage zone. This device can provide necessary support during the hoisting process while allowing a certain amount of sliding to release some of the restraint stress. The sliding saddle device here includes a saddle body and a sliding component, wherein the sliding component can be a pulley or a slider. A polytetrafluoroethylene friction pair is provided at the bottom of the saddle. Pre-load is applied by a hydraulic jack to temporarily secure the sliding auxiliary lifting point to the chord. Because the friction coefficient of polytetrafluoroethylene is μ≤0.1, the use of polytetrafluoroethylene can reduce sliding resistance and avoid damage to the steel pipe surface. The sliding design can release restraint stress and prevent local buckling. Pre-load is applied by the hydraulic jack to temporarily secure the sliding auxiliary lifting point to the chord, which helps to improve the overall stability of the structure.

[0042] In addition, during the construction of long-span arch ribs, since the concrete cannot participate in bearing when the upper chord pipe at the mid-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 an embodiment, ribbed anchor fittings are implanted circumferentially in the upper chord pipe at the mid-span of 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 fittings 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 enhances the uplift resistance of the anchor fittings and prevents interface peeling. The anchoring depth of the ribbed anchor fittings 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 fittings activate the tensile capacity of the concrete through prestress.

[0043] 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 an embodiment, step S5 further includes the following steps:

[0044] 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.

[0045] S52: Weld triangular stiffening plates between the truss auxiliary lifting points and the arch rib to transform the temporary force transmission 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 transmission structure can be transformed into a permanent strengthening structure, which is beneficial to the long-term use of the structure.

[0046] 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 internal stress distribution of the structure can be adjusted to make it more reasonable, thereby extending the service life of the structure. The increase in precompression stress helps to reduce the cracks generated in the concrete during use due to the action of loads.

[0047] Furthermore, to better ensure the stability and safety of the entire turning process, in one embodiment, a BIM dynamic control system is implanted in step S5. The preset values of the compressive stress in the nodal 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 the 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 nodal plate area exceeds the preset value or the tensile stress of the concrete exceeds the preset value, the lifting speed of the winch is automatically adjusted to decrease. The preset values of the compressive stress in the nodal 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 process. When the monitored stress exceeds the preset value, automatically decreasing the lifting speed of the winch can effectively control the stress within a safe range. During the turning 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.

[0048] The above are only the preferred embodiments of the present invention and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to obtain equivalent embodiments with equivalent changes, but as long as the technical content of the present invention is not departed from, 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 crane, characterized in that, It includes the following steps: S1: According to the difficulty of local buckling of steel pipes or cracking of concrete, demarcate the gusset plate, the covered area of diaphragms and the arch foot strengthening section as difficult-to-damage areas, demarcate the non-node area of the lower chord pipe and the connection transition section between the web members and the chord pipes as moderately-damaged areas, and demarcate the upper chord pipe in the middle span, the free section at the cantilever end and the middle part of the steel pipe without diaphragm coverage as easy-to-damage areas. Design truss auxiliary lifting points on the difficult-to-damage areas to transfer pressure, design sliding auxiliary lifting points on the moderately-damaged areas and balance them through the compression of the lower chord pipe, and design anchoring auxiliary lifting points on the easy-to-damage areas and share the load through the tension of concrete, so as to form a tension-compression self-balanced system among the difficult-to-damage areas, the moderately-damaged 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, use the compressive strength of the gusset plate area to form the main force transmission path, and the sliding auxiliary lifting points balance the 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; use the anchoring auxiliary lifting points to utilize the tensile strength of concrete to absorb the remaining tensile stress; S3: Control the synchronous operation of the double winches in a graded manner. Demarcate the flipping angle of 0 - 30° as the initial stage, the flipping angle of 30 - 60° as the transition stage, and the flipping angle of 60 - 90° as the completion stage. In the initial stage, lock the hydraulic lock of the sliding auxiliary lifting point to make the lower chord pipe form a continuous beam structure, and increase the load ratio of the truss auxiliary lifting point. Gradually release the displacement constraint of the sliding saddle in the transition stage, and activate the prestress compensation device of the anchoring auxiliary lifting point in the completion stage. When it is detected that the radial deformation of the upper chord pipe in the middle span exceeds 1 / 50 of the steel pipe diameter, automatically apply force to generate a reverse torque; S4: After the arch rib is flipped to the designed configuration, complete the conversion of the self-balanced state and conduct the conversion of the force system; S5: Through intelligent monitoring and feedback adjustment until the entire hoisting process is completed.

2. The method for assisting the turning over of an arch rib by using a winch and a cable crane according to claim 1, wherein Longitudinally weld an H-shaped steel truss in the covered area of the gusset plate in the difficult-to-damage area to form a force transmission channel for the truss auxiliary lifting point. 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.

3. A method for assisting the turning over of an arch rib by using a winch and a cable crane according to claim 2, characterized in that The section height of the H-shaped steel truss is 0.6 - 0.8 times the diameter of the chord pipe.

4. A method for assisting the turning of an arch rib by using a winch and a cable crane 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. A method for assisting the turning over of an arch rib by using a winch and a cable crane according to claim 1, characterized in that Install a slidable saddle device in the non-node area of the lower chord pipe in the moderately-damaged area, set a polytetrafluoroethylene friction pair at the bottom of the saddle, and apply a pre-pressure through a hydraulic jack to make the sliding auxiliary lifting point form a temporary consolidation with the chord pipe.

6. A method for assisting the turning over of an arch rib by using a hoist and a cable crane according to claim 1, characterized in that Circumferentially implant ribbed anchorages in the upper chord pipe in the middle span of the easy-to-damage area, and the prestressed steel strands of the anchoring auxiliary lifting point penetrate the steel pipe wall to form a composite tensile system with the core concrete.

7. A method for assisting the turning over of an arch rib by using a winch and a cable crane according to claim 6, characterized in that, The anchoring depth of the ribbed anchorage is greater than or equal to twice the wall thickness of the steel pipe.

8. A method for assisting the turning over of an arch rib by using a hoist and a cable crane according to claim 1, characterized in that, The 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; S52: Weld triangular stiffening plates between the truss auxiliary lifting point and the arch rib to convert the temporary force transmission structure into a permanent strengthening structure; S53: Apply secondary tension to the steel strands of the anchoring auxiliary lifting point to increase the pre-compression stress of the concrete.

9. A method for assisting the turning over of an arch rib by using a winch and a cable crane according to claim 1, characterized in that, In the step S5, a BIM dynamic control system is implanted, and a preset value of compressive stress in the gusset plate area and a preset value of tensile stress of concrete are preset in the control system. Strain data of each area are collected every 15° of flipping angle. 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 hoisting speed of the winch is automatically adjusted and reduced.

10. A method for assisting the turning over of an arch rib by using a hoist and a cable crane according to claim 1, characterized in that, In the step S1, a carbon fiber grid reinforcement belt for stress transition is arranged at the junction of the easily damaged area and the moderately damaged area.

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