Large-span and large-tonnage vertical lifting movable bridge and opening method

Abstract

The invention discloses a large-span and large-tonnage vertical lifting movable bridge and an opening method, and relates to the technical field of bridges, the large-span and large-tonnage vertical lifting movable bridge comprises a main beam, four bridge towers, cross beams between the towers, supports, four double-drum winches and eight balancing weights; the section of each bridge tower is shaped like a Chinese character'wang ', four grooves are formed in each bridge tower, two grooves serve as running channels of a main beam lifting point, and the other two grooves serve as running channels of a balancing weight; the main beam is provided with eight symmetrical lifting points, the double-winding-drum winch comprises coaxial double winding drums, the two ends of the steel wire rope are connected with the lifting points and the balance weight respectively, and the balance weight balances more than 97% of the weight of the main beam. The double-drum winch is adopted, the pressure of a hoisting point is dispersed, and the compact layout of the bridge tower shaped like the Chinese character'wang 'is combined, so that the structural design, manufacturing and mounting difficulty is reduced, the limitation of the traditional technology is broken through, larger span and tonnage requirements are met, land and waterway traffic is considered, and the practicability and the popularization value are high.

Description

Technical Field

[0001] This invention belongs to the field of bridge technology, specifically a large-span, large-tonnage vertical lifting and opening bridge and its opening method. Background Technology

[0002] Vertical lift-operated bridges are a special type of bridge structure where the main girder can be raised and lowered like an elevator to accommodate both water and land traffic needs. When the main girder is raised, ships can pass underneath; when the main girder is lowered, vehicles can pass on the bridge.

[0003] Vertical lifting bridges are generally classified into hydraulic type and winch type, depending on the lifting system.

[0004] Hydraulic bridges use a hydraulic system to lift the main beam from below, similar to using jacks to lift a car, or to pull it upwards from above. For example, invention patent CN119491443A discloses a vertical lifting and opening bridge that pulls upwards from above the main beam. The main advantage of hydraulic bridges is that they do not require a counterweight, resulting in smaller structural volume and footprint. The disadvantage is high energy consumption, and they are generally suitable for small-span, lightweight opening bridges.

[0005] The winch-lifting type is a common method used in vertical lifting and lowering bridges both domestically and internationally. It is suitable for almost all spans and tonnages, and its basic principle is the same as that of an elevator. A counterweight is usually installed to reduce the load; typically, the counterweight balances the majority of the main beam's weight, for example, 97%. The motor drive system only needs to overcome a very small portion of the main beam's weight, resulting in limited energy consumption. Specifically, this type of lifting bridge has a tower, with a winch at the top. Several steel wire ropes are wound around the winch drum. One end of each rope is connected to the main beam of the bridge, and the other end is connected to the counterweight. The rotation of the drum drives the main beam to rise and fall. When large ships need to pass under the bridge, the main beam is vertically raised to a certain height to meet navigation requirements; when there is no navigation requirement, the main beam is lowered to its lowest position, connecting land traffic on both sides.

[0006] Vertical lifting bridges typically have towers at the four corners, with a winch at the top of each tower. Each winch suspends a lifting point on the main beam at one end and a counterweight at the other. Traditional single-drum winch-type vertical lifting bridges are limited by technology; once the bridge span and opening tonnage reach a certain level, further breakthroughs are not possible. The span and weight of a lifting bridge are complementary; a large span often means a large tonnage.

[0007] However, with the continuous development of the opening bridge technology towards larger spans and larger tonnages, constraints have also emerged: First, as the lifting tonnage increases, the drum diameter of the winch also needs to increase accordingly due to force requirements, but the drum diameter is limited by factors such as manufacturing processes, material technology, and installation difficulties and cannot be increased infinitely. For example, the drum diameter generally does not exceed 4m, and the nominal drum diameter of the Qingshan Opening Bridge on the Wuhan Right Bank Avenue, the largest opening bridge currently under construction in China, is 3.5m. Second, as the lifting tonnage increases, the design of the main beam suspension points becomes more complex and difficult to implement due to force requirements, manufacturing processes, and material technology. Limited by the technical level, the traditional single-drum winch lifting type vertical lifting opening bridge cannot be further improved when the bridge span and opening tonnage reach a certain level. Therefore, there is an urgent need for a vertical lifting opening bridge structure that can adapt to larger spans and tonnages. Summary of the Invention

[0008] The object of the present invention is to provide a large-span and large-tonnage vertical lifting opening bridge and an opening method, which reduce the structural design, manufacturing, and installation difficulties of the opening bridge to adapt to larger bridge spans and opening tonnages.

[0009] To achieve the above object, the technical solution of the present invention is as follows: A large-span and large-tonnage vertical lifting opening bridge includes a main beam, bridge towers, crossbeams between towers, bearings, double-drum winches, and counterweights.

[0010] The main beam is the core horizontal load-bearing member in the bridge structure that directly bears loads such as vehicles and pedestrians. Eight suspension points are added to it, which are used to anchor the steel ropes of the double-drum winches. Four suspension points are arranged at each end of the main beam near the shore, and the four suspension points are symmetrically distributed at each end of the main beam to ensure balanced force. The preferred material of the main beam is steel, and the structural form can be a steel box girder, a steel truss girder, or a steel beam-arch composite structure.

[0011] The bridge towers are the core vertical load-bearing members in the bridge structure. There are four in total, which are respectively arranged at the four corner points of the bridge. A double-drum winch is installed at the top of each bridge tower. One end of the steel rope wound around the drum is suspended from the main beam, and the other end is suspended from the counterweight. The cross-section of the bridge tower is in the shape of a "king". There are four grooves on each bridge tower, and two of the grooves serve as the running channels for the suspension points of the main beam, and the other two grooves serve as the running channels for the counterweights. The preferred material of the bridge tower is concrete, and a pedestrian passage running through the upper and lower parts is provided inside the bridge tower for maintenance during the operation period or for tourists to pass through.

[0012] The inter-tower crossbeam is a horizontal load-bearing component in the transverse direction of the bridge, connecting the two bridge towers. It is fixedly connected between two adjacent bridge towers, forming a lateral support structure. When the bridge is open and there is no daily navigation demand, the main girder needs to be lowered to its lowest position to connect land traffic on both banks. At this time, the main girder is supported by supports on the top surface of the inter-tower crossbeam, and its stress state is similar to that of a conventional bridge that does not need to be opened. The bridge towers provide supporting foundations when the main girder is closed. The inter-tower crossbeam is preferably made of concrete and uses a hollow box structure to reduce its self-weight while ensuring structural strength.

[0013] The support is fixedly installed on the top surface of the crossbeam between the towers. It is used to support and fix the main beam when the main beam is closed, so that the stress state of the main beam is similar to that of a conventional bridge. The support is a component that is also present in conventional bridges. It is used to support and fix the main beam on the top surface of the crossbeam between the towers.

[0014] The core lifting power component is the double-drum winch, consisting of four units. Each winch includes a wire rope, two drums, two electric motors, a mechanical transmission system, a reduction gear, two brakes, and four safety braking systems. The two drums are coaxially mounted, and the mechanical transmission system is coaxially connected to both drums. Both electric motors are driven by the mechanical transmission system. The reduction gear is connected in series between the electric motors and the mechanical transmission system to adjust the speed and increase torque. Two brakes are installed at one end of each drum, and the four safety braking systems are divided into two groups, installed at both ends of each drum, ensuring safe and reliable lifting. The number and specifications of the wire rope wound on both drums are identical, ensuring synchronous winding and unwinding. The mechanical transmission system drives the two drums to rotate synchronously, realizing the winding and unwinding of the wire rope and the lifting of the load.

[0015] There are eight counterweights in total, each matched to a lifting point. The counterweights are suspended from one end of a steel wire rope and are used to balance over 97% of the main beam's weight, significantly reducing the load on the electric motor. The preferred materials for the counterweights are concrete, alloy, steel, or cast iron.

[0016] The working principle of this invention's vertical lifting and opening bridge is as follows: Each of the four bridge towers is equipped with a double-drum winch. Several steel wire ropes are wound around the drums, with one end connected to the main beam of the opening bridge and the other end connected to the counterweight. When there is no navigation demand, the main beam of the opening bridge is in its lowest position, connecting land traffic on both banks. At this time, the main beam is connected to the top surface of the crossbeam between the towers via supports, and the stress state of the main beam is similar to that of a conventional bridge that does not need to be opened, so the double-drum winches do not need to be activated. When large ships need to pass under the bridge, the motors of the double-drum winches are activated, and the mechanical transmission system transmits power to the drums through a series of mechanical structures. The rotation of the drums drives the main beam to rise and the counterweight to fall via the steel wire ropes. When the ships have passed under the bridge and the main beam needs to be reset, the drums rotate in the opposite direction, driving the main beam to fall and the counterweight to rise via the steel wire ropes.

[0017] A large-span and large-tonnage vertical lifting opening bridge proposed by the present invention significantly enhances the coordination between mechanical equipment and civil engineering structures on the basis of traditional vertical lifting opening bridges, which is specifically reflected in the following aspects: Firstly, a double-drum winch is used to replace the traditional single-drum winch. Under the same lifting tonnage requirement, the diameter of a single drum can be reduced, the manufacturing and installation difficulties of the drum can be lowered, and the limitation of the existing process on the drum size can be broken through; this improvement not only optimizes the mechanical structure, but also greatly reduces the technical difficulties in the manufacturing and installation processes of the drum, and improves the construction efficiency.

[0018] Secondly, eight lifting points are provided on the main girder, which are connected to the two drums of the double-drum winch one by one, dispersing the local pressure of the lifting points. This design cleverly disperses the local pressure borne by the lifting points, thus significantly reducing the design and manufacturing difficulties of the lifting points in the design and manufacturing processes, and ensuring the safety and stability of the bridge.

[0019] Furthermore, in order to better meet the layout requirements of the winch, counterweight and the lifting points of the main girder, the cross-section of the bridge tower structure adopts an innovative "king" - shaped design. This design not only has a compact and reasonable layout, but also effectively solves the problem that the internal area of the traditional bridge tower cross-section cannot be symmetrically arranged. In the traditional design, the internal area of the bridge tower cross-section is mainly divided into three areas: the running channel of the lifting points of the main girder, the running channel of the counterweight and the maintenance channel. As Figure 1 shown in the traditional bridge tower, it is difficult to achieve symmetry in these areas under the traditional layout, resulting in the bridge tower bearing eccentric pressure for a long time, and a horizontal displacement towards the side with larger force will occur at the top of the tower, affecting the operation accuracy of the equipment. Especially for concrete bridge towers, with the creep of concrete, the inclination of the tower body will gradually intensify. However, the "king" - shaped bridge tower cross-section layout cleverly arranges the running channels of the lifting points of the main girder and the counterweight symmetrically on both sides of the cross-section, and the maintenance ladder is arranged in the middle area, making full use of the space and adapting to the layout requirements of the double-drum winch, counterweight and lifting points. Such a design makes the bridge tower basically in an ideal axial compression state, giving full play to the compressive performance of concrete and ensuring the vertical stability of the tower body. This not only significantly improves the durability of the structure, but also guarantees the long-term stable operation of the equipment.

[0020] Combining the above features, the present invention has achieved a major breakthrough in the adaptability of bridge span and opening tonnage, and can meet the requirements of larger-span bridges and higher opening tonnages, bringing new solutions and development directions to the field of bridge engineering. Brief Description of the Drawings

[0021] Figure 1 It is a schematic plan view of a traditional single-drum winch lifting type vertical lifting opening bridge.

[0022] Figure 2 This is the schematic plan layout of the double-drum hoisting vertical-lifting opening bridge of the present invention.

[0023] Figure 3 This is the schematic longitudinal elevation layout of the double-drum hoisting vertical-lifting opening bridge of the present invention.

[0024] Figure 4 This is the schematic transverse elevation layout of the double-drum hoisting vertical-lifting opening bridge of the present invention.

[0025] Figure 5 This is the schematic plan layout of the double-drum hoist of the present invention.

[0026] Figure 6 This is the schematic longitudinal elevation layout of the double-drum hoist of the present invention.

[0027] Figure 7 This is the schematic transverse elevation layout of the double-drum hoist of the present invention.

[0028] Wherein: main girder 1; lifting point 1.1; bridge tower 2; crossbeam between towers 3; support 4; double-drum hoist 5; steel wire rope 5.1; drum 5.2; electric motor 5.3; mechanical transmission system 5.4; reduction gear 5.5; brake 5.6; counterweight 6. Specific embodiments

[0029] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific examples described herein are some embodiments of the present invention, rather than all embodiments, and are not used to limit the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0030] The present invention provides a large-span and large-tonnage vertical-lifting opening bridge, which is applicable to vertical opening bridges with a span of more than 100 m and a tonnage of more than 2,000 tons. The present invention uses a double-drum hoist to replace the traditional single-drum hoist, reducing the manufacturing and installation difficulties of the drum; the main girder is provided with two lifting points, dispersing the local pressure at the lifting points and reducing the design and manufacturing difficulties of the lifting points; in addition, in order to adapt to the layout of the hoist, counterweight and main girder lifting points, the cross-section of the bridge tower structure adopts a compact and reasonable "king" shape. Compared with the traditional single-drum hoisting vertical-lifting opening bridge, the present invention can adapt to larger bridge spans and opening tonnages.

[0031] Referring to the accompanying drawings, the present invention provides a large-span and large-tonnage vertical-lifting opening bridge, including a main girder (1), a bridge tower (2), a crossbeam between towers (3), a support (4), a double-drum hoist (5), and a counterweight (6).

[0032] The main girder 1 is the core horizontal load-bearing component of the bridge structure that directly bears the loads of vehicles, pedestrians, etc. The main girder 1 of the vertical lifting and opening bridge is equipped with eight lifting points 1.1 for anchoring the wire rope 5.1 of the winch 5.

[0033] Lifting point 1.1 is an anchor box, a box-shaped load-bearing component specifically designed for anchoring tensile components such as wire ropes and stay cables, and for transmitting concentrated loads. The anchor box converts the enormous tensile force of the wire rope / stay cable into a uniform surface load, transferring it to the main beam of the bridge, such as a steel box girder or steel truss girder, thus preventing localized cracking or deformation due to stress concentration. In long-span bridges, the tensile force of the wire rope can reach hundreds of tons. If directly connected to the main beam steel plate, it can cause localized stress far exceeding the material's bearing capacity, leading to tearing of the steel plate. In this invention, the anchor box, through its enclosed box-shaped structure and internal stiffening components, converts point / line tensile force into a surface load, uniformly transmitting it to the entire main beam. Anchor boxes are mostly rectangular / trapezoidal in shape, with cross-sectional dimensions customized according to the tensile force, such as 30-60cm wide and 50-100cm high. They are formed by welding / riveting high-strength steel plates. The anchor box includes a pressure plate, internal stiffening plates, anchor plates / anchor pipes, and connecting flanges / connecting plates. The pressure plate directly bears the concentrated tensile force of the wire rope / cable and transfers the force to the stiffening plates. The thickness is 15-30mm, increasing with the greater the tensile force. The surface is provided with anti-slip textures or pin holes, which are used to fix the wire rope clamps. The internal stiffening plates enhance the box's resistance to torsion and deformation, preventing the box from collapsing or cracking under stress. They are arranged at intervals of 10-20cm along the direction of the tensile force. Welded perpendicularly to the outer shell of the anchor box, a grid-like support structure is formed to enhance overall rigidity. Anchor plates / anchor pipes are used to position the wire ropes / cables, ensuring the tension direction is consistent with the design and preventing eccentric loading. The anchor plates are perpendicular to the bearing plate, with a central hole slightly larger than the wire rope diameter. Anchor pipes are welded to the outside of the anchor plates to guide the wire rope direction. Connecting flanges / connecting plates fix the anchor boxes to the surface of the main beam, enabling force transfer between the anchor boxes and the main beam. The connecting flanges / connecting plates are made of the same material as the main beam, such as Q345q bridge steel. They are connected to the main beam via high-strength rivets or welds. The connecting plate area must be large enough to prevent localized crushing. All eight anchor boxes on the bridge must correspond one-to-one with four double-drum winches, with each double drum equipped with two anchor boxes. The pin hole positions and connecting plate heights of the anchor boxes must be strictly uniform to ensure synchronous winding and unwinding of the two wire ropes, preventing the risk of eccentric loading due to tilting of the main beam during lifting and lowering.

[0034] The bridge tower 2 is the core vertical load-bearing member in the bridge structure. For a vertical-lift opening bridge, bridge towers 2 are generally provided at the four corner points. There are a total of four bridge towers 2 in the whole bridge. The bridge towers 2 are set on the shore through the foundation, or set on the riverbed near the shore through the foundation. Two bridge towers 2 are set on each side of the shore. The cross-section of the bridge tower 2 is in the shape of "king", specifically, the cross-section of the top surface of the bridge tower 2 is in the shape of "king", and the "king" shape is a horizontal "king" shape, that is, the "king" shape is arranged along the bridge axis. There are four grooves on the bridge tower 2. Two of the grooves serve as the running channels for the suspension points 1.1 of the main beam 1, and the other two grooves serve as the running channels for the counterweight 6.

[0035] The cross-bridge beam 3 between the towers is a horizontal load-bearing member in the cross-bridge direction. The cross-bridge beam 3 between the towers is used to connect the two bridge towers 2 in the cross-bridge direction. When there is no daily navigation requirement for the opening bridge, the main beam 1 needs to be lowered to the lowest position to connect the land transportation on both sides. At this time, the main beam 1 is supported on the top surface of the cross-bridge beam 3 between the towers through the support 4. The stress state of the main beam 1 is similar to that of a conventional bridge that does not need to be opened.

[0036] The support 4 is a component that a conventional bridge also has. The support 4 is set on the top surface of the cross-bridge beam 3 between the towers. When there is no daily navigation requirement for the opening bridge, the main beam 1 is located above the support 4. The support 4 is located between the main beam 1 and the cross-bridge beam 3 between the towers. The support 4 is used to support and fix the main beam 1. The support 4 can be considered to adopt a pot rubber support or a steel support, and is fixedly installed on the top surface of the cross-bridge beam 3 between the towers through the anchor bolts. The top surface of the support 4 is adapted to the bottom surface of the main beam 1 and is used to support the main beam 1 in the closed state. The support 4 is an existing component of a conventional bridge and will not be elaborated here one by one.

[0037] A double-drum winch 5 is set at the top of each bridge tower 2. One end of the steel wire rope 5.1 wound around the drum 5.2 is hung on the suspension point 1.1 on the main beam 1, and the other end is hung with the counterweight 6.

[0038] The double-drum winch 5 includes two coaxial drums 5.2, with the same number and specifications of steel wire rope 5.1 wound on each drum. A mechanical transmission system 5.4 drives the two drums 5.2 to rotate synchronously, enabling the winding and unwinding of the steel wire rope 5.1 and the lifting and lowering of the load. The core components of each double-drum winch 5 include several steel wire ropes 5.1, two drums 5.2, two electric motors 5.3, a mechanical transmission system 5.4, a reduction gear 5.5, two brakes 5.6, and four safety braking systems 5.7. The double-drum winches 5 are installed at the top of the bridge tower 2, with a total of four sets for the entire bridge. In this invention, the mechanical transmission system 5.4 included in the double-drum winch 5 enables power transmission and synchronous control of the double-drum winch, serving as a key intermediate component connecting the electric motors and the drums. The mechanical transmission system 5.4 receives power from the two electric motors 5.3 and transmits it to the two drums 5.2 through an internal mechanical structure, ensuring the two drums rotate in sync and preventing uneven tension on the wire rope and tilting of the main beam due to differences in drum speeds. The mechanical transmission system 5.4 includes mechanical components such as gear sets, couplings, and drive shafts. Precise mechanical meshing or connection ensures the stability of power transmission and the synchronization of drum rotation. The reduction gear 5.5 is a power adjustment component adapted to the drum speed requirements and works in conjunction with the mechanical transmission system. The electric motors typically output high speeds and low torques, while the drums 5.2 require lower speeds and higher torques to drive the wire rope winding and unwinding for stable lifting / lowering of the heavy-tonnage main beam. Therefore, the function of the reduction gear 5.5 is to reduce the speed transmitted by the electric motors while increasing the output torque, so that the drum speed and torque match the load requirements of the main beam lifting and lowering.

[0039] The reduction gear 5.5 is an integrated reduction component such as a gear reducer. It achieves the conversion between speed and torque through the gear meshing speed ratio design and must be matched with the mechanical transmission system 5.4 to ensure power transmission efficiency. The brake 5.6 is a conventional braking control component of the double-drum winch, used for precise stopping during lifting and lowering. When the main beam 1 is raised to a designated height, such as the lifting height to meet navigation requirements or the lowering height to restore land traffic, the rotation of the brake drum 5.2 achieves stable stopping of the main beam, preventing the main beam from shifting due to inertia as the drum continues to rotate. Simultaneously, when the main beam is lowered to its lowest position without navigation requirements, it helps to fix the drum state and prevent wire rope slack. Two sets of brakes 5.6 correspond one-to-one with the two drums 5.2 of the double-drum winch. Each drum is equipped with one brake. The brakes 5.6 are conventional industrial braking structures such as disc brakes or drum brakes, directly locking the drum through friction, providing reliable braking under normal operating conditions. Safety braking system 5.7 is a redundant safety component designed to address emergency risks. It is an emergency protection device distinct from conventional brakes. In extreme or emergency situations such as brake 5.6 failure, motor malfunction, wire rope overload / breakage risk, or main beam tilting, it activates by forcibly locking drum 5.2 to achieve an emergency stop, preventing main beam falls, counterweight loss of control, and other safety accidents, thus ensuring the safety of the bridge structure and traffic. Safety braking system 5.7 is a braking component independent of brake 5.6, with overload detection and failure triggering functions. It provides dual safety protection for both drums, with each drum corresponding to two sets of safety braking systems to ensure that drum rotation can be forcibly stopped in an emergency.

[0040] The double-drum winch is fixedly installed on the top platform of the bridge tower by pre-embedded steel plates and high-strength bolts. The two drums 5.2 are coaxially installed through bearing seats. The mechanical transmission system 5.4 adopts a gear transmission mechanism and is meshed with the end gears of the two drums 5.2. Two motors 5.3 are connected in parallel to the input end of the mechanical transmission system 5.4. The reduction device 5.5 is connected in series between the motors 5.3 and the mechanical transmission system 5.4 to convert the high speed and low torque of the motors into the low speed and high torque required by the drums. Two sets of brakes 5.6 are electromagnetic brakes, which are installed on the outer ends of the two drums 5.2 respectively. Four sets of safety braking systems 5.7 are disc brakes, which are installed on the outer ends of the two drums respectively, forming a double safety guarantee with the brakes 5.6.

[0041] The wire rope is made of high-strength galvanized steel wire rope. One end of the wire rope is fixedly connected to the lifting point by a pin, and the other end is wound around the corresponding drum and fixed by a pressure plate. The counterweight is a concrete counterweight block with a lifting lug on its top surface, which is fixedly connected to the other end of the wire rope by a pin.

[0042] To demonstrate the advantages of the twin-drum winch of this invention, taking the lifting of a 2000-ton main beam as an example, the differences in drum parameters and difficulty between the twin-drum and traditional single-drum winches are explained below, with a detailed comparative analysis as follows: First point: Comparison of core parameters, design differences based on the 2000-ton lifting requirement. Assuming the 2000-ton main beam is subjected to symmetrical force distribution at eight lifting points according to this invention, the single-drum scheme requires four single-drum winches, each bearing a load of 500 tons, while the double-drum scheme requires four double-drum winches, each with two drums, each drum bearing a load of 250 tons. Key parameters are compared in the table below: Secondly: Differences in manufacturing difficulty, a comprehensive breakthrough from materials to processes. Firstly, regarding the requirements for materials and processing equipment: Among them, the single-roller solution: 1. High-strength steel of Q690 grade or above must be used. The material is difficult to smelt, and the content of harmful elements such as sulfur and phosphorus must be controlled to ≤0.02% to avoid cold cracking during welding. 2. The processing requires an ultra-large CNC lathe of 6.3 meters or more. There are only about 20 such machines in China, and the processing cycle is as long as 45-60 days. 3. Roll welding requires a special narrow-gap submerged arc welding machine. If the weld length exceeds 20m, overall annealing is required to relieve stress. The annealing furnace volume must be ≥5m×8m. Only a few manufacturers in China have this type of annealing furnace.

[0043] Among them, the dual-spindle solution: 1. Conventional Q345 bridge steel can be used, which is convenient for material procurement and has mature smelting and rolling processes; 2. Machining only requires a 3-5 meter conventional CNC lathe, shortening the processing cycle to 15-20 days; 3. The weld length is shortened to 12-15m, and ordinary submerged arc welding machines can be used. Local annealing can meet the stress requirements, and large annealing equipment is not required.

[0044] Secondly, regarding the difficulty of precision control: Among them, the single-roller solution: 1. The roundness error of the 4.5m diameter drum needs to be controlled within 0.5mm, and the coaxiality error ≤0.1mm / m. Multiple measurements and adjustments are required during processing, and the scrap rate is as high as 15%-20%. 2. The processing of wire rope grooves requires specialized milling equipment, with a groove spacing error of ≤0.1mm to prevent the wire rope from jumping out of the groove. The processing precision requirements are comparable to those of aerospace components.

[0045] Among them: Dual-spindle solution: 1. For a drum with a diameter of 3m, the allowable roundness error is ≤0.8mm, and the coaxiality error is ≤0.15mm / m. Conventional processing equipment can meet the requirements, and the scrap rate is reduced to 3%-5%. 2. The error of the rope groove pitch can be relaxed to 0.2mm, and an ordinary milling machine can complete it, and the processing efficiency is increased by 3 times.

[0046] Third point: The difference in installation difficulty, adapting to the scenarios from transportation to hoisting First, the comparison of transportation and hoisting conditions is as follows in the table: Second, the comparison of the adaptability with the pylon structure: Among them, the single-drum scheme: 1. The drum diameter is 4.5m, and the width of the top platform of the pylon needs to be ≥6m, resulting in a 30% increase in the top cross-section of the pylon and a 25% increase in the concrete consumption. Each pylon consumes about 80m more concrete

[0050] , ,

[0049] , , , , ; 2. The single lifting point has concentrated stress, and the pylon needs to be additionally provided with shear-resistant brackets. The size of the brackets is ≥1.5m×2m, increasing the construction difficulty.

[0047] Among them, the double-drum scheme: 1. The drum diameter is 3m, and the width of the top platform of the pylon only needs 4m, which is precisely adapted to the groove of the "king" - shaped pylon, without the need to expand the tower body; 2. The double lifting points disperse the stress, and the pylon does not need additional shear-resistant components, and the construction process is reduced by 15%.

[0048] Fourth point: In terms of the design of operation safety redundancy Among them, the single-drum scheme: 1. The single drum bears a load of 500 tons. If the brake fails, such as the brake pads are worn, it can only rely on a set of safety braking systems. When braking emergently, the impact force of the steel wire rope is ≥1200kN, which is likely to cause damage to the rope body; <00​​​​​​​​​​​ 1. Technical feasibility: It avoids the manufacturing and installation bottlenecks of large-diameter, heavy-load single-drum construction, and can use conventional equipment and materials, reducing reliance on special processes; 2. Economic efficiency: Reduces drum manufacturing costs, installation costs, and total life-cycle maintenance costs; 3. Safety: The redundant design of multiple lifting points and multiple braking systems significantly reduces the risk of tilting and the probability of equipment failure during the main beam lifting process, making it more suitable for heavy-duty scenarios.

[0051] Therefore, the double-drum scheme is a key innovation that breaks through the traditional technical limitations of large-span, large-tonnage vertical lifting and opening bridges, and provides a better technical solution for lifting main beams of 2,000 tons and above.

[0052] The counterweight 6 is a counterweight device used in vertical lifting and opening bridges to balance the weight of the main girder. Its function is to offset most, for example, 97% of the main girder's weight, reducing the driving load on the double-drum winch and ensuring the economy and safety of the main girder lifting process. The counterweight forms a linkage structure with the double-drum winch and the main girder through steel wire ropes. The counterweight is suspended from one end of the steel wire rope of the double-drum winch, and the other end of the steel wire rope is anchored to the main girder through a lifting point. Each counterweight corresponds to one steel wire rope and one main girder lifting point. A total of eight counterweights are set in the entire bridge, perfectly matching the eight lifting points of the main girder and the number of steel wire ropes of the double-drum winch, forming a symmetrical steel wire rope-main girder-counterweight transmission unit. The counterweight material can be preferably concrete, alloy, steel, or cast iron, and can be flexibly selected according to the bridge tonnage, manufacturing cost, and other requirements. Its weight needs to be precisely designed according to the total weight of the main girder to ensure that the double-drum winch only needs to overcome a very small portion of the main girder's weight to drive the lifting, reducing energy consumption and equipment load. During the bridge's lifting and lowering process, the counterweight and the main beam move in opposite directions: when the main beam needs to be lifted to allow navigation of ships under the bridge, the double-drum winch drives the wire rope to wind up and down, and the counterweight descends simultaneously as the main beam rises; when the main beam needs to be reset to restore land traffic, the drums rotate in the opposite direction, and the counterweight rises simultaneously as the main beam descends, thus maintaining the stability of the lifting system through weight balance.

[0053] In a long-span, high-tonnage vertical lifting and opening bridge, the counterweight 6, drum 5.2, wire rope 5.1, main beam 1, and bridge tower 2 form a stable transmission and load-bearing connection system through "support-winding-suspension". The entire bridge has four bridge towers and four double-drum winches. The four double-drum winches contain eight drums 5.2, eight lifting points 1.1, and eight counterweights 6.

[0054] Bridge tower 2 and drum 5.2 form a support and installation foundation relationship. Bridge tower 2 is the core vertical load-bearing component, providing a fixed installation carrier for drum 5.2. Each bridge tower 2 is equipped with a double-drum winch at its top, and drum 5.2 is the core component of the double-drum winch. Each winch contains two coaxial drums 5.2, meaning that drum 5.2 is directly fixed to the preset installation position at the top of bridge tower 2 through the overall structure of the winch. The load-bearing capacity of bridge tower 2 must match the total load of drum 5.2, wire rope 5.1, main beam 1, and counterweight 6 to ensure that drum 5.2 remains stable when lifting and lowering heavy objects.

[0055] The drum 5.2 and the wire rope 5.1 are in a winding and transmission relationship. The drum 5.2 is the drive end for winding and unwinding the wire rope 5.1. Power is transmitted between them through winding. The middle of each wire rope 5.1 is tightly wound on a drum 5.2, and the two drums 5.2 of the same double-drum winch must be wound with the same number and specifications of wire rope 5.1. The two drums 5.2 of each winch can be driven to rotate synchronously through the mechanical transmission system 5.4 and the electric motor 5.3 of the double-drum winch. During rotation, the friction force drives the wire rope 5.1 to wind up to shorten its length or unwind to extend its length, providing power for the subsequent lifting and lowering of the main beam 1 and the counterweight 6.

[0056] The wire rope 5.1 is suspended at both ends from the main beam 1 and the counterweight 6. Wire rope 5.1 is a flexible transmission component connecting the drum 5.2 to the loads, including the main beam 1 and the counterweight 6. It employs a symmetrical suspension structure with one end suspending the main beam and the other end suspending the counterweight. Four suspension points 1.1 are located on the surface of the main beam 1 at each end facing both banks. Suspension points 1.1 are used to anchor the wire ropes. One end of each wire rope 5.1 is fixed to a suspension point 1.1 on the main beam 1 via an anchoring structure such as bolts, forming a one-to-one suspension relationship. Eight suspension points correspond to eight wire ropes, which can distribute the localized stress on the main beam 1. The other end of each wire rope 5.1 directly suspends a counterweight 6. There are a total of eight counterweights for the entire bridge, perfectly matching the number of suspension points and wire ropes. The weight of the counterweight 6 must be designed to balance the vast majority of the weight of the main beam 1, such as 97%, to reduce the driving load on the drum 5.2.

[0057] Two drums 5.2 at the top of a single bridge tower 2 are connected to two lifting points 1.1 and two counterweights 6 of the main beam 1 via two steel wire ropes 5.1, forming an independent lifting unit. The eight lifting units of the four bridge towers work together to achieve the vertical lifting of the main beam 1: the bridge tower 2 provides support for the drums 5.2, which are installed at the top of the tower. Each drum 5.2 is wound with a steel wire rope. One end of each steel wire rope 5.1 is connected to the lifting point 1.1 of the main beam 1, and the other end is connected to the counterweight 6. When the drums 5.2 rotate, the main beam 1 is suspended and lifted. The counterweights 6 move in the opposite direction to the main beam to balance the weight.

[0058] The "king" - shaped cross - section of the pylon 2 is formed by casting with a formwork. Four grooves run through the pylon 2 in the height direction. Among them, the inner two grooves correspond to the running track of the lifting point 1.1, and the outer two grooves correspond to the running track of the counterweight 6. The width of the grooves is slightly larger than the widths of the lifting point 1.1 and the counterweight 6, ensuring no interference during the lifting process. In the present invention, the cross - section of the pylon 2 is "king" - shaped, and a dedicated lifting - point passage is provided on the pylon 2. The passage of the lifting point 1.1 is a groove, and each lifting point corresponds to a groove. The width and height of the lifting point 1.1, that is, the anchor box, need to be precisely matched with the groove dimensions. For example, the groove width is 55 cm, the anchor box width is 50 cm, with a 5 - cm gap reserved, ensuring that the anchor box slides smoothly along the passage when the main girder is lifted and does not collide with the pylon.

[0059] A running passage for the counterweight 6 is provided on the pylon 2. The running passage of the counterweight is a groove, and each counterweight corresponds to a groove. The counterweight moves up and down inside the groove.

[0060] The two grooves serving as the running passage of the lifting point 1.1 are provided on one side of the pylon 2 in the transverse direction of the bridge, specifically on the side of the pylon 2 facing the main girder 1 in the transverse direction of the bridge. The two grooves serving as the running passage of the lifting point 1.1 are spaced apart on the same side of each pylon 2. One side of the main girder 1 facing the lifting - point running passage is set in a horizontal U - shape. The two vertical ends of the U - shape face the lifting - point running passage, and an anchor box, which is a lifting point, is provided on the upper surface of each of the two vertical ends of the U - shape. The anchor box is located on the upper surface of the vertical end of the U - shape. One vertical end of the U - shape and an anchor box on the vertical end are jointly located inside one lifting - point running passage, that is, one groove. When the drum 5.2 rotates, the anchor box moves up and down along the lifting - point running passage, that is, the groove, driving the main girder 1 to move up and down.

[0061] The two grooves serving as the running passage of the counterweight 6 are provided on one side of the pylon 2 in the transverse direction of the bridge, specifically on the side of the pylon 2 facing away from the main girder 1 in the transverse direction of the bridge. That is, the two grooves serving as the running passage of the lifting point 1.1 and the two grooves serving as the running passage of the counterweight 6 are arranged opposite to each other on the pylon 2. The two grooves serving as the running passage of the counterweight are spaced apart on the same side of each pylon 2. When the drum 5.2 rotates, it drives the counterweight to move up and down along the running passage of the counterweight, that is, the groove. The running passages of the lifting points and the counterweights are symmetrically arranged on both sides of the cross - section of the "king" - shaped cross - section, and a pedestrian or maintenance staircase is arranged in the area between the running passages of the lifting points and the counterweights.

[0062] In the present invention, there are a total of eight counterweights, each counterweight corresponds to a lifting point, and the counterweight and its corresponding lifting point are arranged transversely opposite to each other. The two drums 5.2 included in each double - drum winch 5 are arranged longitudinally on the top surface of the pylon 2.

[0063] The comparison between the "king" - shaped cross - section bridge tower of the present invention and the cross - sections of traditional bridge towers has obvious advantages in terms of structural design and stress. The detailed comparison between the two is as follows in the table: For long - span and large - tonnage vertical - lift opening bridges, the wind - resistance advantage of the "king" - shaped cross - section can also indirectly improve the overall safety of the bridge: Stability of the hanging points and counterweights during operation: Under wind loads, the deformation of the tower body is smaller, which can avoid the deviation of the running paths of the main - beam hanging points and counterweights, and reduce the additional forces on the hanging - point steel ropes, such as side bending and wear. Co - stress of the bridge tower and the main beam: The tower body has strong anti - lateral - displacement performance, which can reduce the "horizontal drag force" of the wind load on the main beam and avoid loosening or damage of the connection between the main beam and the support.

[0064] Under wind loads, the "king" - shaped cross - section bridge tower has three core advantages: multi - cavity flow - division and resistance reduction, torsion and lateral - resistance of the rigid - frame structure, and uniform stress distribution. It is significantly superior to the traditional solid - cross - section bridge tower, especially suitable for the strong - wind environment requirements of long - span and large - tonnage opening bridges. At the same time, it takes into account lightweight and economy, and is a targeted optimization design for the scenario of "long - span + complex loads".

[0065] After having the above - mentioned structural features, the working principle of the vertical - lift opening bridge of the present invention is as follows: A set of double - drum winches 5 is arranged on the top of each of the four bridge towers 2 of the whole bridge. The drum 5.2 of the winch winds several steel ropes 5.1. One end of the steel rope 5.1 is connected to the main beam 1 of the opening bridge, and the other end is connected to the counterweight 6. When there is no navigation demand daily, the main beam 1 of the opening bridge is placed at the lowest position to connect the land traffic on both sides. At this time, the main beam 1 is connected to the top surface of the tower - to - tower cross - beam 3 through the support 4. The stress state of the main beam 1 is similar to that of a conventional bridge that does not need to be opened, and the double - drum winch 5 does not need to be started. When large ships need to pass under the bridge, the motor 5.3 of the double - drum winch 5 is started, and the mechanical transmission system 5.4 transmits the power through a series of mechanical structures to the drum 5.2. The rotation of the drum 5.2 drives the main beam 1 to lift and the counterweight to descend through the steel rope 5.1. When the ship has completed passing under the bridge and the main beam 1 needs to be reset, the drum 5.2 rotates in the reverse direction, and drives the main beam 1 to descend and the counterweight 6 to lift through the steel rope 5.1.

[0066] Daily closed state: The main beam 1 is supported on the top surface of the tower - to - tower cross - beam 3 through the support 4 to connect the land traffic on both sides. At this time, the double - drum winch 5 is powered off, the brake 5.6 and the safety - braking system 5.7 are both in the braking state, the steel rope 5.1 remains taut, the weight of the main beam 1 is mainly borne by the support 4, and the counterweight 6 is suspended in the outer groove of the bridge tower 2.

[0067] When the bridge is in the open state (i.e., there is navigation demand under the bridge): the motor 5.3 of the double-drum winch 5 is started. The motor 5.3 outputs power, which is reduced and increased in torque by the reduction device 5.5 and then transmitted to the mechanical transmission system 5.4. The mechanical transmission system 5.4 drives the two drums 5.2 to rotate synchronously clockwise, the wire rope 5.1 is wound up, and the main beam 1 is lifted upward. At the same time, the counterweight 6 moves downward along the outer groove of the bridge tower 2 under the action of gravity, balancing most of the weight of the main beam 1. When the main beam 1 is lifted to the preset height, the motor 5.3 is de-energized, the brake 5.6 and the safety braking system 5.7 brake synchronously, the drums 5.2 stop rotating, the main beam 1 remains in the lifted position, and the navigation demand of large ships under the bridge is met.

[0068] Reset to closed state: The motor 5.3 of the double-drum winch 5 is started to rotate in the reverse direction, and the mechanical transmission system 5.4 drives the two drums 5.2 to rotate synchronously counterclockwise. The wire rope 5.1 is slowly released, and the main beam 1 moves downward along the inner groove of the bridge tower 2 under the action of gravity, while the counterweight 6 is pulled upward. When the bottom surface of the main beam 1 is in contact with the top surface of the support 4, the motor 5.3 is de-energized, the brake 5.6 and the safety braking system 5.7 brake, and the main beam 1 returns to the closed state, connecting the land traffic on both sides.

[0069] The above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A large-span, high-tonnage vertical lifting and opening bridge, comprising a main beam (1), bridge towers (2), and inter-tower crossbeams (3), wherein the inter-tower crossbeams (3) are fixedly connected between two adjacent bridge towers (2) along the transverse direction of the bridge to form a transverse support structure; supports are installed on the top surface of the inter-tower crossbeams (3), and the supports are used to support the main beam (1), characterized in that: One double-drum winch (5) is provided on each bridge tower (2). Each double-drum winch (5) includes two drums (5.2) arranged coaxially. Steel ropes (5.1) are wound on both of the two drums (5.2). One end of each steel rope (5.1) is fixedly connected to a lifting point (1.1) on the main girder (1) in a one-to-one correspondence, and the other end is fixedly connected to a counterweight (6) in a one-to-one correspondence. The cross-section of the bridge tower (2) is in a "king" shape along the bridge axis. Four grooves are provided on the bridge tower (2), two of which are the lifting and running channels for the lifting points (1.1), and the other two are the lifting and running channels for the counterweights (6).

2. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: The two grooves serving as the running channels for the lifting points (1.1) are provided on one side of the bridge tower (2) in the transverse direction of the bridge facing the main girder (1), and the two grooves serving as the running channels for the lifting points (1.1) are arranged at intervals on each bridge tower (2).

3. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: The two grooves serving as the running channels for the counterweights (6) are provided on one side of the bridge tower (2) in the transverse direction of the bridge facing away from the main girder (1). The two grooves serving as the running channels for the counterweights are arranged at intervals on each bridge tower (2). The two grooves serving as the running channels for the lifting points (1.1) and the two grooves serving as the running channels for the counterweights (6) are arranged oppositely on the bridge tower (2).

4. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: One side of the main girder (1) facing the running channel for the lifting points is arranged in a horizontal U shape. The two vertical ends of the U shape face the running channel for the lifting points. One lifting point (1.1) is provided on the upper surface of each of the two vertical ends of the U shape. The lifting point (1.1) is an anchor box, and the anchor box is located on the upper surface of the vertical end of the U shape. One vertical end of the U shape and an anchor box on the vertical end are jointly located in one running channel for the lifting points. When the drum (5.2) rotates, the anchor box moves up and down along the running channel for the lifting points, driving the main girder (1) to move up and down.

5. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: Four lifting points (1.1) are provided at each of the two ends of the main girder 1 facing both banks. The lifting points (1.1) are located on the surface of the main girder (1), and the lifting points (1.1) are connected to the steel ropes (5.1).

6. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: There are a total of eight counterweights (6), and the eight counterweights are adapted to each lifting point (1.1) in a one-to-one correspondence. Each counterweight (6) and its corresponding lifting point (1.1) are arranged oppositely in the transverse direction of the bridge.

7. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: The running channels for the lifting points and the counterweights are symmetrically arranged on both sides of the cross-section of the "king" shape. A pedestrian walkway is arranged in the area between the running channels for the lifting points and the counterweights on the bridge tower (2).

8. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: The two drums (5.2) included in each double-drum winch (5) are arranged along the bridge axis on the top surface of the bridge tower (2).

9. The large-span, large-tonnage vertical lifting and opening bridge according to claim 1, characterized in that: The double-drum winch (5) also includes two electric motors (5.3), a mechanical transmission system (5.4), a speed reduction device (5.5), two brakes (5.6), and four safety braking systems (5.7). The mechanical transmission system (5.4) is coaxially connected to the two drums (5.2), and the two electric motors (5.3) are driven by the mechanical transmission system (5.4). The speed reduction device (5.5) is connected in series between the electric motor (5.3) and the mechanical transmission system (5.4). The two brakes (5.6) are respectively installed at one end of the two drums (5.2), and the four safety braking systems (5.7) are divided into two groups, respectively installed at both ends of the two drums (5.2).

10. A method for opening a large-span, large-tonnage vertical lifting and opening bridge as described in any one of claims 1-9, characterized in that: The method includes: Normal closed state: The main beam (1) is supported on the top surface of the crossbeam (3) between the towers by the support (4), connecting the land traffic on both sides. The double drum winch (5) is in the power-off state. The brake (5.6) and the safety braking system (5.7) are both in the braking state. The wire rope (5.1) is kept taut. The weight of the main beam (1) is mainly borne by the support (4). The counterweight (6) is suspended in the groove on the outside of the bridge tower (2). Open state: When there is a need for navigation under the bridge, the motor (5.3) of the double drum winch (5) is started. The motor (5.3) outputs power, which is reduced and increased in torque by the reduction device (5.5) and then transmitted to the mechanical transmission system (5.4). The mechanical transmission system (5.4) drives the two drums (5.2) to rotate clockwise synchronously. The wire rope (5.1) is wound up and lifted, which drives the main beam (1) to rise. The counterweight (6) moves downward along the outer groove of the bridge tower (2) under the action of gravity to balance the weight of the main beam (1). When the main beam (1) is lifted to the preset height, the motor (5.3) is de-energized, the brake (5.6) and the safety braking system (5.7) brake synchronously, the drum (5.2) stops rotating, and the main beam (1) remains in the lifted position, meeting the navigation needs of large ships under the bridge. Reset to closed state: The motor (5.3) of the double-drum winch (5) is started to rotate in the opposite direction, and the mechanical transmission system (5.4) drives the two drums (5.2) to rotate counterclockwise synchronously. The wire rope (5.1) is released, and the main beam (1) moves downward along the inner groove of the bridge tower (2) under the action of gravity. The counterweight (6) is pulled upward. When the bottom surface of the main beam (1) is in contact with the top surface of the support (4), the motor (5.3) is de-energized, the brake (5.6) and the safety braking system (5.7) brake, and the main beam (1) returns to the closed state, connecting the land traffic on both sides.

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