Integral unloading device for main tower cross beam truss girder support

Abstract

The utility model discloses an integral unloading device for a main tower cross beam truss girder support, which comprises a load-bearing main beam which penetrates from the lower part of a truss girder upper chord member and is connected with the truss girder upper chord member; a bearing support steel plate is fixed at the bottom of the bearing main beam at the lifting point of the suspender pocket, and is provided with a hole for the suspender to pass through; each lowering device comprises a plurality of tensioning supports, a plurality of suspenders and a plurality of continuous jacks; the tensioning steel support is fixed on the surface of the main tower cross beam, the suspender sequentially penetrates through the tensioning support, the main tower cross beam, the bearing main beam and the bearing supporting steel plate and then is provided with the lower anchor plate, the upper end of the steel strand reversely penetrates through the continuous jack, and the continuous jack is installed on the tensioning steel support; the suspender is made of a steel strand. The utility model solves the problems that the main tower cross beam truss girder support needs to be dismantled by matching with large hoisting equipment, the number of constructors is large, the labor intensity is high, the construction efficiency is low and the safety risk is high.

Description

Technical Field

[0001] This utility model relates to the field of crossbeam supports for main towers of cable-stayed bridges. More specifically, this utility model relates to an overall unloading device for the crossbeam truss support of a main tower. Background Technology

[0002] The main tower crossbeams of cable-stayed bridges typically employ a non-grounded support system where pre-embedded components are installed on the tower body to connect to load-bearing supports. Load-bearing main beams are then installed on these supports, longitudinal truss beams are mounted on the main beams, and distribution beams are installed on the truss beams. Conventional dismantling methods involve moving the truss beams in groups to the outside of the beam surface before hoisting them for dismantling. However, this method results in a large height-to-width ratio after dismantling the truss beams, posing a risk of instability. Furthermore, this method is cumbersome, carries high safety risks, and has poor controllability. Therefore, a safer approach is to lower the entire support structure to the beam surface before dismantling. Generally, the entire support structure is lowered using jacks and precision-rolled threaded steel bars as the main load-bearing system, gradually lowering the support structure to the ground in stages. When lowering the main tower crossbeam support structure, due to the large drop height, numerous joints in the precision-rolled threaded steel bars, and their relatively weak shear resistance, additional auxiliary lifting rods are required. Simultaneously, the jacks often lack synchronization, leading to uneven stress on the support system. During the dismantling of the support structure, the system may sway horizontally due to center of gravity deviation and wind load, which is detrimental to the stress system of the dismantling device and can easily damage or scratch the main tower structure. Against this backdrop, an overall dismantling device for the main tower crossbeam truss support structure was developed. Summary of the Invention

[0003] The purpose of this utility model is to provide a device for the overall unloading of the main tower crossbeam truss support, which solves the weaknesses of the main tower crossbeam truss support's overall unloading lifting rods, such as the insufficient shear resistance of the fine-rolled threaded steel and the need for auxiliary lifting rods; it also solves the problem of poor synchronization of the jacks during the overall unloading of the main tower crossbeam truss support, which easily leads to uneven stress on the support system; it solves the problem of swaying caused by wind loads and eccentric loads during the overall unloading of the main tower crossbeam truss support; it solves the problem of damage to the concrete surface caused by the swinging of the main tower crossbeam truss support when it comes into contact with the main tower structure; and it solves the problems of requiring large lifting equipment, a large number of construction workers, high labor intensity, low construction efficiency, and high safety risks in the dismantling of the main tower crossbeam truss support.

[0004] The technical solution adopted by this utility model to solve this technical problem is: a main tower crossbeam truss support overall unloading device, comprising:

[0005] The load-bearing main beam passes through and connects to the lower part of the upper chord of the truss beam; a load-bearing support steel plate is fixed at the bottom of the load-bearing main beam at the lifting point of the hanger, and holes are opened on the load-bearing support steel plate for the hanger to pass through;

[0006] The system includes several lowering devices, each comprising: several tension supports, several suspenders, and several continuous jacks; the tension steel supports are fixed to the surface of the main tower crossbeam; the suspenders pass sequentially through the tension supports, the main tower crossbeam, the load-bearing main beam, and the load-bearing support steel plate before being installed with lower anchor plates; the upper end of the steel strand passes through the continuous jacks in reverse, and the continuous jacks are installed on the tension steel supports; the suspenders are made of steel strands.

[0007] As a further embodiment of this utility model, the load-bearing main beam is made of double-jointed I-beams and steel gusset plates welded together.

[0008] As a further embodiment of this utility model, it also includes a guide wheel with a spring, which is installed on the upper and lower chords at both ends of the truss beam.

[0009] A further embodiment of this utility model is: it also includes a cable-passing channel, which is provided in the main tower crossbeam for the suspender to pass through the main tower crossbeam.

[0010] A further aspect of this utility model is that several lowering devices are arranged symmetrically to the left and right of the truss beam.

[0011] As a further embodiment of this utility model, a connecting lug is provided at the bottom of the load-bearing main beam, the connecting lug is connected to an anti-sway steel wire rope, and the bottom of the anti-sway steel wire rope is wound on a reel through a turning device, the reel being disposed on the beam surface.

[0012] This utility model has at least the following beneficial effects: In the overall unloading device for the main tower crossbeam truss support, the lifting rods are made of steel strands, overcoming the weaknesses of the poor shear resistance of fine-rolled threaded steel and the need to set auxiliary lifting rods; in this embodiment, the power system adopts a one-to-four continuous jack, and the stroke synchronization of each jack is controlled by a hydraulic pump station, which can ensure the balanced force of the support system; one end of the anti-sway steel wire rope is fixed on the load-bearing main beam, and the other end of the anti-sway steel wire rope is extended to the fixed reel through a fixed pulley group set on the beam surface to greatly reduce the degree of swaying when the crossbeam support is unloaded as a whole; spring-loaded guide wheels are fixed at both ends of the truss beam to ensure that if the support system swings and comes into contact with the main tower structure during the overall unloading of the crossbeam support system, the unloading can be smooth and without jamming, and the appearance of the concrete can be protected from damage; this device does not require the cooperation of large lifting equipment, requires fewer construction personnel, has low labor intensity, greatly improves construction efficiency, and avoids the safety risks of dismantling the main tower crossbeam support.

[0013] Other advantages, objectives and features of this invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of this invention. Attached Figure Description

[0014] Figure 1 This is a front view of the main tower crossbeam truss support integral unloading device according to an embodiment of this utility model;

[0015] Figure 2 This is a side view of the main tower crossbeam truss support integral unloading device according to an embodiment of this utility model;

[0016] Figure 3 This is a top view of the main tower crossbeam truss support overall unloading device according to an embodiment of this utility model;

[0017] Figure 4 yes Figure 1 A magnified view of a portion of the image;

[0018] Figure 5 yes Figure 2 A magnified view of a portion of the image.

[0019] Among them, 1-main tower crossbeam, 2-truss beam, 3-bearing main beam, 4-bearing support steel plate, 5-suspender rod, 6-cable passage, 7-tensioning support, 8-lower anchor plate, 9-continuous jack, 10-anti-sway wire rope, 11-line reel, 12-steering device, 13-connecting lug, 14-guide wheel, 15-U-shaped clamp. Detailed Implementation

[0020] The present invention will now be described in detail and completely with reference to the accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention with reference to the accompanying drawings, it should be particularly noted that the technical solutions and features provided in the various parts of the present invention, including the following description, can be combined with each other without conflict.

[0021] Furthermore, the embodiments of the present invention described below are generally only a part of the embodiments of the present invention, and not all of the embodiments. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the protection scope of the present invention.

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific implementation process is as follows:

[0023] like Figures 1-5 As shown, this utility model provides an overall unloading device for the main tower crossbeam truss support, comprising:

[0024] The main load-bearing beam 3 passes through and connects to the upper chord of the truss beam 2. In this embodiment, the main load-bearing beam 3 and the upper chord of the truss beam 2 are connected and limited by a U-shaped clip 15. The load-bearing support steel plate 4 is fixed on the bottom flange plate of the main load-bearing beam 3 at the lifting point of the hanger 5. The load-bearing support steel plate has a hole for the hanger 5 to pass through.

[0025] The system includes several lowering devices, each comprising: several tension supports 7, several suspenders 5, and several continuous jacks 9. The tension steel supports are fixed to the surface of the main tower crossbeam. The suspenders 5 pass sequentially through the tension supports 7, the cable-passing holes of the main tower crossbeam 1, the gaps of the load-bearing main beam 3, and the load-bearing support steel plate 4 before being installed with lower anchor plates 8. During construction, the working clamps of the lower anchor plates are tightened. The upper ends of the steel strands are passed through the continuous jacks 9 in reverse. The continuous jacks 9 are then installed on the tension steel supports. The steel strands are adjusted one by one using the continuous jacks 9 to ensure that their initial stress is basically consistent. The suspenders 5 are made of steel strands, and the continuous jacks 9 in this embodiment are ZLD100 continuous jacks 9.

[0026] Before lowering the main tower crossbeam truss beam 2 support frame using the overall unloading device, a final inspection is conducted to ensure the integrity of all components of the continuous jacks 9, the absence of oil leaks in hydraulic components, the cleanliness of the oil, the installation status of the upper and lower anchor points of the steel strands, the absence of hard bends or jamming points in the steel strands, the connection between the load-bearing main beam 3 and the truss beam 2, the welds of the load-bearing main beam 3, and the lateral connections between the truss beams 2. Once the unloading command is issued, the formal unloading process begins. The unloading operation is directed by a designated person. Operators of the hydraulic pump station on the crossbeam and personnel pulling the steel wire ropes on the beam surface are each equipped with walkie-talkies to maintain communication. The unloading of each jack should be slow, even, and consistent. During the unloading process, the alternating lifting speed of the continuous jacks 9 should be consistent with the tightening speed of the anti-sway ropes. A monitoring team is assigned to observe the positional relationship between the truss beam 2 support system and the main tower. After the truss beam 2 support frame is completely unloaded onto the beam surface, it is disassembled manually with the assistance of the tower crane and transported to the designated storage area on the ground.

[0027] This technical solution may also include the following technical details to better achieve the technical effect: the load-bearing main beam 3 is made of double-jointed I-beams and steel gusset plates welded together.

[0028] This technical solution may also include the following technical details to better achieve the technical effect: it also includes a spring-loaded guide wheel 14, which is installed on the upper and lower chords at both ends of the truss beam 2. When the guide wheel is installed, it protrudes from both ends of the truss beam 2 to ensure that if the support system swings and comes into contact with the main tower structure during the overall unloading of the crossbeam support, the unloading can be smooth and without jamming, and the appearance of the concrete can be protected from damage.

[0029] This technical solution may also include the following technical details to better achieve the technical effect: it also includes a cable passage 6, which is set in the main tower crossbeam for the suspender 5 to pass through the main tower crossbeam. In this embodiment, during the construction of the main tower crossbeam reinforcement, a PVC pipe is pre-embedded at the designed position of the suspender 5 to form the cable passage.

[0030] This technical solution may also include the following technical details to better achieve the technical effect: several lowering devices are arranged symmetrically to the left and right of the truss beam 2. In this embodiment, four sets of lowering devices are provided, respectively close to the four corners of the truss beam 2, and the synchronous control of each continuous jack 9 is achieved by a hydraulic pump station with four continuous jacks 9.

[0031] This technical solution may also include the following technical details to better achieve the technical effect: A connecting lug is provided at the bottom of the main load-bearing beam 3. An anti-sway wire rope 10 is connected to the connecting lug 13 via a shackle. The bottom of the anti-sway wire rope is wound onto a reel 11 via a turning device 12 (fixed pulley). The reel is operated by a hand-cranked winch and is positioned on the beam surface. In this embodiment, a tower crane is used to pull the upper end of the anti-sway wire rope to the connecting lug of the main load-bearing beam 3, where it is fixed with a shackle. The anti-sway wire rope is appropriately tightened on the reel on the beam surface.

[0032] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and embodiments shown and described herein.

Claims

1. A device for the overall unloading of a main tower crossbeam truss support, characterized in that, include: The load-bearing main beam passes through and connects to the lower part of the upper chord of the truss beam. A load-bearing support steel plate is fixed at the bottom of the main beam at the lifting point of the boom, and holes are made on the load-bearing support steel plate for the boom to pass through; The system includes several lowering devices, each comprising: several tension supports, several suspenders, and several continuous jacks; the tension steel supports are fixed to the surface of the main tower crossbeam; the suspenders pass sequentially through the tension supports, the main tower crossbeam, the load-bearing main beam, and the load-bearing support steel plate before being installed with lower anchor plates; the upper end of the steel strand passes through the continuous jacks in reverse, and the continuous jacks are installed on the tension steel supports; the suspenders are made of steel strands.

2. The main tower crossbeam truss support integral unloading device as described in claim 1, characterized in that, The load-bearing main beam is welded together from double-section I-beams and steel gusset plates.

3. The main tower crossbeam truss support integral unloading device as described in claim 1, characterized in that, It also includes spring-loaded guide wheels, which are mounted on the upper and lower chords at both ends of the truss beam.

4. The main tower crossbeam truss support integral unloading device as described in claim 1, characterized in that, It also includes cable-passing channels, which are set in the main tower crossbeams to allow the suspenders to pass through the main tower crossbeams.

5. The main tower crossbeam truss support integral unloading device as described in claim 1, characterized in that, Several lowering devices are arranged symmetrically to the left and right sides of the truss beam.

6. The main tower crossbeam truss support integral unloading device as described in claim 1, characterized in that, The bottom of the load-bearing main beam is equipped with a connecting lug, which is connected to an anti-sway steel wire rope. The bottom of the anti-sway steel wire rope is wound on a spool through a turning device, and the spool is set on the beam surface.

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