Cable crane and parallel type load bearing cable erection method for hoisting steel beam of suspension bridge

Abstract

The application relates to the technical field of suspension bridge construction, and particularly discloses a cable crane parallel type load bearing cable erecting method for hoisting a suspension bridge steel beam, which comprises the following steps: step 1, load bearing cable anchorage construction: pouring a temporary concrete pier, and embedding a spiral steel pipe between a suspension bridge cable saddle anchorage and the temporary concrete pier to form a load bearing cable anchorage; step 2, installation of the load bearing cable: using a suspension bridge tower as a tower of the cable crane to install the load bearing cable; and step 3, cable adjustment: installing a Beidou positioning sensor and a cable force sensor on the load bearing cable, and synchronously adjusting the cable by sharing data of the Beidou positioning sensor and the force sensor, so that each load bearing cable of a cable group is adjusted to the same height. The technical problem that, when the cable crane load bearing cable adopts a parallel structure, the height and stress between different load bearing cables are difficult to adjust, the stress is uneven, the car on the load bearing cable is inclined and the local stress is too large is solved.

Description

Method for Erection of Parallel Load-Bearing Cables for Steel Beams of Suspension Bridges Technical Field

[0001] This invention relates to the field of suspension bridge construction technology, specifically to a method for erecting parallel load-bearing cables using cable hoisting for steel beam hoisting of suspension bridges. Background Technology

[0002] To accommodate the increased span and lifting capacity of cable-stayed cranes, it is necessary to increase the number of load-bearing cables to form a cable ensemble that shares the load. However, with an increased number of load-bearing cables, the trolley needs to simultaneously ride on different load-bearing cables and distribute its force evenly across them. Therefore, during erection, it is crucial to ensure that a row of load-bearing cables remains at the same height to achieve uniform load distribution. Otherwise, the trolley will become skewed on the cable ensemble, leading to uneven stress on each cable and excessive stress in certain areas. Adjusting multiple load-bearing cables to the same height is not only cumbersome but also extremely difficult.

[0003] To address the cumbersome and difficult process of maintaining a uniform height for all load-bearing cables after increasing their number, existing technologies employ a series-type cable assembly. This series-type structure uses a continuous load-bearing rope that deflects through saddles at the top of the towers on both banks, winding around guide wheels and main cable deflectors on the cable anchorage, repeatedly folding back and forth to form a cable assembly with multiple load-bearing cables. Its core principle is to control multiple load-bearing cables under the same load-bearing steel wire rope. During adjustment, simply tightening or loosening a single-sided winch simultaneously changes the sag of all load-bearing cables, ensuring consistent height. For example, patent document CN117216938A discloses a design method for a cable-stayed installation system for a large-span, upper-bearing steel-concrete arch bridge that utilizes this series-type structure.

[0004] While the aforementioned technologies can solve the problem of adjusting the alignment and height of the load-bearing cables in a cable assembly, the use of a series structure for the load-bearing cables means that the entire cable assembly is composed of a single, continuous steel wire rope. If one point in the load-bearing cable breaks, the entire assembly will collapse, resulting in poor reliability. Therefore, while parallel structures solve the cable adjustment problem, they also introduce corresponding safety hazards. Consequently, parallel cable assemblies have emerged in the industry. For example, patent document CN206986723U discloses an anchoring device for a parallel structure of cable-stayed crane load-bearing ropes. In this type, each load-bearing cable is an independent structure, preventing the collapse of the entire assembly due to a break in one cable. Therefore, its reliability is higher than that of a series structure.

[0005] In a parallel cable-stayed crane, each cable operates independently, thus preventing the entire crane from collapsing due to a break in one cable, resulting in high reliability. However, because each cable is independent, it requires individual adjustment. The height and tension of each cable affect the even distribution of the lifting weight, making adjustment difficult. Consequently, despite its high reliability, the adoption rate of parallel cable-stayed cranes remains low. Therefore, the industry urgently needs a method for erecting parallel cable-stayed cranes that facilitates cable adjustment. Summary of the Invention

[0006] The purpose of this invention is to provide a method for erecting parallel load-bearing cables for cable-stayed bridge steel beam hoisting, in order to solve the technical problems mentioned above in the prior art where the height and stress between different load-bearing cables are difficult to adjust when the load-bearing cables of the cable-stayed bridge adopt a parallel structure, resulting in uneven stress, trolley skew on the load-bearing cables, and excessive local stress.

[0007] To solve the above problems, the technical solution adopted by the present invention is as follows: a method for erecting parallel load-bearing cables for hoisting steel beams of suspension bridges, characterized by comprising the following steps:

[0008] Step 1, Construction of the load-bearing cable anchor: When constructing the cable saddle anchor of the suspension bridge, a temporary concrete support is poured on the foundation of the cable saddle anchor next to the support pier of the cable saddle anchor of the suspension bridge. A spiral steel pipe for anchoring the cable saddle anchor and the temporary concrete support pier is pre-embedded between the cable saddle anchor support pier and the temporary concrete support pier, and concrete is poured inside the spiral steel pipe.

[0009] Step 2, Installation of load-bearing cables: Using the suspension bridge tower as the tower for the cable crane, the load-bearing cables are installed. The load-bearing cables adopt a parallel structure, and the two ends of the load-bearing cables are wrapped around the spiral steel pipe to form a temporary anchor.

[0010] Step 3, Cable Adjustment: Install Beidou positioning sensors and cable force sensors at multiple points along the load-bearing cable to determine the reference load-bearing cable, adjust the tension of the load-bearing cable, use the cable force sensor to provide feedback on the tension of the load-bearing cable, and compare with Beidou position information to adjust all load-bearing cables to the same height before locking the load-bearing cable at the end.

[0011] The beneficial effects of this implementation plan are as follows:

[0012] 1. Parallel Structure: Since each load-bearing cable uses an independent steel wire rope, it is necessary to ensure that the height of each cable is consistent during erection. However, most existing technologies use cable force sensors for cable adjustment. However, cable force sensors can only reflect the magnitude of the force on the load-bearing cable, not its height in real time. When the cable force of the load-bearing cables is adjusted to be consistent, it can only reflect that the magnitude of the force is evenly distributed, but the height may not be consistent. When the trolley is on the load-bearing cable, its posture is tilted. When lifting the load, due to the tilt of the trolley, the load-bearing cable with the lower height will experience increasing force, and gradually the force on the load-bearing cables will become inconsistent, requiring readjustment. Therefore, the existing technology of adjusting the cable by the magnitude of the load-bearing cable force is not accurate enough, resulting in inconsistent height of the cable group. Although each load-bearing cable is initially evenly stressed, the trolley may tilt, and the local stress may gradually increase during the lifting process. This application uses BeiDou positioning for adjustment in conjunction with cable force sensors. First, the height benchmark of the load-bearing cable is determined using the BeiDou positioning sensor, and then the cable force sensor is used for adjustment. The combination of control technology and positioning technology reduces the difficulty of cable adjustment and also increases the adjustment accuracy. Therefore, after adjustment, not only is the force on the load-bearing cable consistent and the height uniform, but the accuracy is also higher.

[0013] 2. The load-bearing cables in this application adopt a parallel structure, with each cable using an independent steel wire rope. The cables do not affect each other, allowing for individual cable erection and anchoring. Individual steel wire ropes can also be replaced, resulting in high safety. The anchoring foundation is provided based on the cable saddle anchor, ensuring high reliability. The final temporary anchor can be directly cast within the cable saddle anchor, eliminating the need for separate anchor selection, making it more environmentally friendly.

[0014] Furthermore, the construction of the load-bearing cable anchorage in step 1 also includes the following steps: Step 101: During the construction of the cable saddle anchorage of the suspension bridge, a temporary concrete support for the cable crane is simultaneously poured next to the cable saddle anchorage support. The temporary concrete support and the cable saddle anchorage share the same foundation and are poured side by side. At the same time, a spiral steel pipe is pre-embedded between the temporary concrete support and the cable saddle anchorage support. A reinforcing cage is installed inside the spiral steel pipe, and a concrete pouring hole is reserved on the outside of the spiral steel pipe; Step 102: Concrete is poured into the pre-embedded spiral steel pipe using the reserved concrete pouring hole. The concrete grade is consistent with that of the temporary concrete support and the cable saddle anchorage; Step 103: After the concrete strength of the temporary concrete support and the spiral steel pipe is qualified, an arc-shaped cable saddle is installed on the spiral steel pipe.

[0015] Furthermore, a connecting steel pipe is pre-embedded between the temporary concrete support and the cable saddle anchor support.

[0016] Furthermore, step 3 includes the following steps: Step 301: Install Beidou positioning sensors and cable force sensors at multiple points along the mid-span of each load-bearing cable in the cable group. Use the Beidou positioning sensors to perform preliminary cable adjustment, so that each load-bearing cable in the cable group is initially adjusted to the same height; Step 302: After the preliminary cable adjustment is completed, the tower crane assists in lifting the trolley to the load-bearing cable and installing it on the load-bearing cable. The lifting cable and traction cable are then threaded around the trolley to complete the overall installation of the cable crane; Step 303: After installation, use the trolley for trial lifting, applying the load to the cable crane in stages. Use the cable force sensors to detect the cable force, adjust the tension of the load-bearing cable, and use the cable force sensors to provide feedback on the tension of the load-bearing cable. Compare the information with the Beidou positioning sensors, which detect the height of the load-bearing cable. Share data and coordinate synchronous cable adjustment to ensure that all load-bearing cables in the cable group are at the same height.

[0017] Furthermore, a hydraulic tie rod is installed between the load-bearing cable and the anchorage. One end of the hydraulic tie rod is connected to the load-bearing cable, and the other end of the hydraulic tie rod is anchored to the cable saddle anchorage support through a hinge seat. The tension of the hydraulic tie rod is controlled by a controller based on the feedback value of the cable force sensor, which is installed above the connection point between the hydraulic tie rod and the load-bearing cable.

[0018] Furthermore, an adjusting rope is fixedly connected to the main body of the load-bearing cable, and the adjusting rope is connected to a winch. Attached Figure Description

[0019] Figure 1 is a schematic diagram of the cable-stayed structure after the installation of the present invention.

[0020] Figure 2 is an enlarged view of position A in Figure 1;

[0021] Figure 3 is a structural schematic diagram of the load-bearing cable anchorage of the present invention;

[0022] Figure 4 is a cross-sectional view of position AA in Figure 3;

[0023] Figure 5 is a cross-sectional view of position BB in Figure 3;

[0024] Figure 6 is a schematic diagram of the connection between the arc-shaped cable saddle and the load-bearing cable. Detailed Implementation

[0025] The following detailed description illustrates the specific implementation method:

[0026] The reference numerals in the accompanying drawings include: 1. Cable saddle anchorage support, 11. Cable saddle anchorage foundation, 2. Spiral steel pipe, 21. Embedded end of cable saddle support, 22. Embedded end of concrete support, 23. Arc-shaped cable saddle, 3. Temporary concrete support, 4. Connecting steel pipe, 5. Load-bearing cable, 6. Winch.

[0027] The implementation is shown in Figures 1-6:

[0028] The method for erecting parallel load-bearing cables using cable hoisting for steel beam hoisting of suspension bridges includes the following steps:

[0029] Step 1, Construction of the Load-Bearing Cable Anchorage: The construction of the suspension bridge cable saddle anchorage includes the construction of the cable saddle anchorage foundation 11 and the construction of the cable saddle anchorage support 1. In this invention, during the construction of the suspension bridge cable saddle anchorage, a temporary concrete support 3 is poured beside the cable saddle anchorage support 1. The temporary concrete support 3 shares a foundation with the cable saddle anchorage support 1, that is, they share the cable saddle anchorage foundation 11. The temporary concrete support 1 and the cable saddle anchorage foundation 11 are connected by reinforcing steel bars to form a high-strength, fatigue-resistant anchoring system. When pouring the cable saddle anchorage support 1 and the temporary concrete support 3, a spiral steel pipe 2 for anchoring the load-bearing cable needs to be pre-embedded between them. Concrete is poured inside the spiral steel pipe 2 to form the load-bearing cable anchorage.

[0030] The load-bearing cable anchor is a key structure for fixing the load-bearing cable, and its construction quality directly affects the stability of the load-bearing cable. The construction of the load-bearing cable anchor in this application includes the following steps:

[0031] Step 101: Pour concrete for temporary concrete support pier 3 and install spiral steel pipe 2: After the construction of the suspension bridge cable saddle anchorage foundation 11 is completed, cable saddle anchorage support piers and temporary concrete support piers 3 are constructed on the cable saddle anchorage foundation 11. The two are poured side by side and share the cable saddle anchorage foundation 11. At the same time, spiral steel pipe 2 is pre-embedded between temporary concrete support pier 3 and cable saddle anchorage support pier 1. In this embodiment, the spiral steel pipe 2 is φ200×2cm in size. The two ends of the spiral steel pipe 2 are the cable saddle support pre-embedded end 21 and the concrete support pre-embedded end 22, respectively. The cable saddle support pre-embedded end 21 is pre-embedded in the cable saddle anchorage support pier 1, and the concrete support pre-embedded end 22 is pre-embedded in the temporary concrete support pier 3. The pre-embedded length of each is 1.8m. A steel cage is set inside the steel pipe, and a concrete pouring hole is reserved on the outside of the steel pipe. In this embodiment, the temporary concrete support pier 3 and the cable saddle anchor foundation 11 are connected by steel bars and cast into a reinforced concrete structure to form a high-strength, fatigue-resistant anchoring system. A connecting steel pipe 4 is also pre-embedded on the side of the spiral steel pipe 2 facing the river surface. The structure of the connecting steel pipe 4 is the same as that of the spiral steel pipe 2, and it is also a spiral steel pipe 2 with a size of φ46×2cm.

[0032] Step 102: Pouring concrete inside the steel pipe: A reinforcing cage is placed inside the spiral steel pipe 2, and concrete is poured into the embedded spiral steel pipe 2 using a pump and a reserved concrete pouring hole. While pouring and vibrating, a special person is arranged to knock on the outer wall of the steel pipe to ensure the compactness of the concrete inside the pipe.

[0033] Step 103: Install the arc-shaped cable saddle 23: After the concrete strength of the temporary concrete support pier 3, the cable saddle anchor pier 1, and the spiral steel pipe 2 is qualified, the arc-shaped cable saddle 23 for installing the cable-stayed crane load-bearing cable 5 is installed on the spiral steel pipe 2. The connection between the arc-shaped cable saddle 23 and the load-bearing cable is shown in Figure 6. The end of the load-bearing cable 5 passes around the spiral steel pipe 2 along the groove on the outside of the arc-shaped cable saddle 23 and overlaps with the main body of the load-bearing cable 5. After overlap, it is fixed with cable clamps. The arc-shaped cable saddle 23 can reduce the friction between the load-bearing cable wire rope and the steel pipe, and at the same time play a buffering role. When installing the arc-shaped cable saddle 23, a truck crane is used to assist in manual installation. The arc-shaped cable saddle 23 is connected to the spiral steel pipe 2 by spot welding.

[0034] Step 2: Using the suspension bridge tower as the tower for the cable crane, install the load-bearing cable 5. The load-bearing cable 5 adopts a parallel structure, and both ends are temporarily anchored to the spiral steel pipe 2.

[0035] Step 201: Use the suspension bridge towers as the towers of the cable cranes, use the main cable to pull across the river, and use nylon ropes to pull the thin steel wire ropes across the river; gradually replace them with thicker steel wire ropes, and finally replace them with load-bearing cable 5.

[0036] Step 202, Tensioning and Anchoring of Load-Bearing Cable 5: The end of the load-bearing cable 5 is fixedly connected to the main body before winding the spiral steel pipe 2. The adjusting rope is connected to the winch 6 after turning through the pulley block. Therefore, the winches 6 on both sides tighten synchronously. The sag of the load-bearing cable 5 can be adjusted by pulling the adjusting rope. After adjusting to the reference, the end of the load-bearing cable 5 wound around the spiral steel pipe 2 along the arc saddle 23 is aligned with the main body of the load-bearing cable 5. After alignment, it is fixed by using cable clamps.

[0037] Step 3, Cable Adjustment: Install Beidou positioning sensors and cable force sensors at multiple points along the load-bearing cable to determine the reference load-bearing cable, adjust the tension of the load-bearing cable, use the cable force sensor to provide feedback on the tension of the load-bearing cable, and compare with Beidou position information to adjust all load-bearing cables to the same height, and lock the load-bearing cables at the ends.

[0038] Step 301: Install Beidou positioning sensors and cable force sensors at multiple points in the mid-span of each load-bearing cable in the cable group. Use the Beidou positioning sensors to perform preliminary cable adjustment so that each load-bearing cable in the cable group is initially adjusted to the same height.

[0039] Step 302: After the initial cable adjustment is completed, the tower crane assists in lifting the trolley onto the load-bearing cable and installing it on the load-bearing cable. The lifting cable (multiplier 4~8) and traction cable are then threaded around the trolley to complete the overall installation of the cable crane.

[0040] Step 303: After installation, conduct a trial lift using a trolley, gradually loading the cable crane with the load (30%→60%→110% of rated load). Use cable force sensors to detect cable force, adjust the tension of the load-bearing cables, and compare the load-bearing cable tension feedback through the cable force sensors. The Beidou positioning sensor detects the height of the load-bearing cables, shares data, and coordinates with the cable force sensors to adjust the cables synchronously, ensuring that all load-bearing cables of the cable assembly are at the same height.

[0041] A hydraulic tie rod is installed between the load-bearing cable 5 and the cable saddle anchor. One end of the hydraulic tie rod is connected to the load-bearing cable, and the other end of the hydraulic tie rod is anchored to the cable saddle anchor support 1 through a hinge seat. The tension of the hydraulic tie rod is controlled by the controller according to the feedback value of the cable force sensor. The cable force sensor is installed above the connection point between the hydraulic tie rod and the load-bearing cable.

[0042] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for erecting parallel load-bearing cables using cable hoisting for steel beam hoisting of suspension bridges, characterized in that: The process includes the following steps: Step 1, Cable Anchorage Construction: During the construction of the cable saddle anchorages for the suspension bridge, temporary concrete supports are poured on the foundation of the shared cable saddle anchorage next to the cable saddle anchorage support pier. A spiral steel pipe for anchoring the cable-stayed crane cable is pre-embedded between the cable saddle anchorage support pier and the temporary concrete support pier, and concrete is poured inside the spiral steel pipe. Step 2, Cable Installation: The suspension bridge towers are used as the towers for the cable-stayed crane. The cable-stayed cranes are installed using a parallel structure, and both ends of the cable-stayed cranes are wound around the spiral steel pipe to form temporary anchorages. Step 3, Cable Adjustment: Beidou positioning sensors and cable tension sensors are installed at multiple points along the cable-stayed crane to determine the reference cable-stayed crane. The tension of the cable-stayed crane is adjusted, and the tension is fed back through the cable tension sensors. The Beidou location information is then compared to adjust the tension of all cable-stayed cranes. After adjusting to the same height, the load-bearing cable is locked at the end; the construction of the load-bearing cable anchor in step 1 also includes the following steps: Step 101, when constructing the suspension bridge cable saddle anchor, a temporary concrete support for the cable crane is poured on the side of the cable saddle anchor support. The temporary concrete support and the cable saddle anchor share the same foundation and are poured side by side. At the same time, a spiral steel pipe is pre-embedded between the temporary concrete support and the cable saddle anchor support. A reinforcing cage is set inside the spiral steel pipe, and a concrete pouring hole is reserved on the outside of the spiral steel pipe; Step 102, concrete is poured into the pre-embedded spiral steel pipe using the reserved concrete pouring hole. The concrete grade is consistent with that of the temporary concrete support and the cable saddle anchor; Step 103, after the concrete strength of the temporary concrete support and the spiral steel pipe is qualified, an arc-shaped cable saddle is installed on the spiral steel pipe.

2. The method for erecting parallel load-bearing cables for hoisting steel beams of suspension bridges according to claim 1, characterized in that: A connecting steel pipe is also pre-embedded between the temporary concrete support and the cable saddle anchor support.

3. The method for erecting parallel load-bearing cables for hoisting steel beams of suspension bridges according to claim 1, characterized in that: Step 3 includes the following steps: Step 301: Install Beidou positioning sensors and cable force sensors at multiple points along the mid-span of each load-bearing cable in the cable group. Use the Beidou positioning sensors to perform preliminary cable adjustment, ensuring that each load-bearing cable in the cable group is initially adjusted to the same height. Step 302: After the preliminary cable adjustment is completed, the tower crane assists in lifting the trolley onto the load-bearing cable and installing it on the load-bearing cable. Thread the lifting cable and traction cable around the trolley to complete the overall installation of the cable crane. Step 303: After installation, use the trolley for trial lifting, applying the load to the cable crane in stages. Use the cable force sensors to detect the cable force, adjust the tension of the load-bearing cable, and use the cable force sensors to provide feedback on the tension of the load-bearing cable. Use the Beidou positioning sensors to locate the height of the load-bearing cable. The Beidou positioning sensors and cable force sensors share data and coordinate cable adjustment to ensure that all load-bearing cables in the cable group are at the same height.

4. The method for erecting parallel load-bearing cables for hoisting steel beams of suspension bridges according to claim 3, characterized in that: A hydraulic tie rod is installed between the load-bearing cable and the cable saddle anchor. One end of the hydraulic tie rod is connected to the load-bearing cable, and the other end of the hydraulic tie rod is anchored to the cable saddle anchor support through a hinge seat. The tension of the hydraulic tie rod is controlled by a controller based on the feedback value of the cable force sensor, which is installed above the connection point between the hydraulic tie rod and the load-bearing cable.

5. The method for erecting parallel load-bearing cables for hoisting steel beams of suspension bridges according to claim 4, characterized in that: An adjusting rope is fixedly connected to the main body of the load-bearing cable, and the adjusting rope is connected to a winch.

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