Force unloading device for relieving temporary anchoring of arch springing

Abstract

The utility model discloses a force unloading device for relieving temporary anchoring of an arch springing, which comprises a reverse jacking mechanism, a reverse jacking mechanism and a force unloading mechanism, the reverse jacking mechanism comprises a rigid supporting structure, one end of the rigid supporting structure can be matched and supported on the outer side face of a temporary anchoring state position at the bottom of an arch rib upper chord, and the other end of the rigid supporting structure is fixed on an arch support; the jacking mechanism comprises an upper sealing plate, a lower sealing plate and a jacking jack set, the upper sealing plate is used for being fixedly connected with the bottom face of an arch rib lower chord in a matched mode, and the lower sealing plate is used for being fixedly connected with the top face of a temporary fixing structure which is temporarily anchored to the lower face of the arch rib lower chord and completes cutting and separation. A jacking jack set is fixed between the upper sealing plate and the lower sealing plate in a matched mode. The temporary fixing structure can help to reduce the probability of instant instability of the arch rib when the temporary fixing structure and the arch rib are connected and supported.

Description

Technical Field

[0001] This utility model relates to the field of bridge construction technology, and in particular to a force-relieving device for releasing temporary anchorage at the arch foot. Background Technology

[0002] Steel-concrete composite arch bridges are widely used in modern bridge construction due to their unique structure, beautiful appearance, and high load-bearing capacity. The arch ribs of these bridges utilize a steel-concrete composite structure. Construction typically involves first erecting the steel arch rib structure, then filling the steel tubes with concrete. Various methods can be employed for constructing the steel arch ribs, including full-span scaffolding, scaffold-free hoisting, low-position assembly and lifting, and rotation construction. The rotation construction method involves dividing the arch ring or the entire superstructure into two half-spans (which can be of different lengths). These half-arches are prefabricated and assembled on both banks of the river using the terrain or simple supports. Then, a power unit is used to rotate the half-arches to the bridge axis or design elevation, merging them to form the full arch. The rotation construction method reduces the amount of work at height and significantly minimizes disruption to traffic below, and is therefore currently being used in some bridge construction projects.

[0003] Currently, the construction of steel pipe arch rib bridge rotation often requires the erection of horizontal assembly scaffolds during assembly. For example, the invention patent application CN 118375076 A discloses a construction method for vertical rotation of arch ribs using rigid jacking. This method requires the pre-installation of main beam supports, main beams, arch feet, and arch rib supports. A pair of arch ribs are then placed on the arch rib supports on the respective sides to support the arch ribs before the corresponding vertical rotation operation can be carried out. After the operation is completed, the main beam supports and arch rib supports also need to be removed. However, if the bridge site is located in a river, it is necessary to erect supports in the water, which will affect navigation and flood discharge to some extent. If the bridge site is located in a valley, there will also be problems with the support being too high, making erection difficult. Therefore, this project studied a new vertical assembly negative angle rotation tensioning method. After the arch rib is vertically assembled, it is rotated downward to the design elevation under the coordinated action of the lowering cable and the wind-holding cable. However, when the arch rib is vertically assembled, a temporary fixing structure needs to be welded to the lower end of the arch rib. At the moment when the temporary fixing structure is removed from the support of the arch rib during the vertical rotation and lowering, a large instantaneous force will be generated, causing the lowering cable of the arch rib and the tower to be suddenly stressed. This may lead to the inability to control the cable force of the lowering system, resulting in the possibility of instantaneous instability of the arch rib. Utility Model Content

[0004] This utility model discloses a force-relieving device for releasing temporary anchorage at the arch foot, which can help reduce the probability of instantaneous instability of the arch rib when the temporary fixing structure is released from the connection support of the arch rib.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] A stress-relieving device for releasing temporary anchorage at the arch foot, comprising:

[0007] The anti-top mechanism includes a rigid support structure, one end of which can match the outer side of the arch rib upper chord in a temporary anchoring state position, and the other end is fixed to the arch seat;

[0008] The lifting mechanism includes an upper sealing plate, a lower sealing plate, and a lifting jack assembly. The upper sealing plate is used to match and fix the bottom surface of the lower chord of the arch rib. The lower sealing plate is used to fix the top surface of the temporary fixed structure that is temporarily anchored below the lower chord of the arch rib and has been cut and separated. The lifting jack assembly is matched and fixed between the upper sealing plate and the lower sealing plate.

[0009] Preferably, the rigid support structure includes a wedge-shaped pad, which includes multiple rigid support plates spaced apart. One end of each rigid support plate can be matched and supported on the outer side of the temporary anchored position at the bottom of the upper chord of the arch rib, and the other end is fixed to the arch seat.

[0010] Preferably, the anti-top mechanism further includes a pre-embedded steel plate, which is pre-embedded in the arch seat, with its top exposed and connected to the other end of the rigid support plate.

[0011] Preferably, the anti-jacking mechanism further includes a shim steel plate, which is fixed to the bottom surface of the upper chord of the arch rib or the top surface of the corresponding temporary fixing structure after the upper chord of the arch rib is disconnected from the temporary fixing structure. Preferably, at least two jacking mechanisms are provided, matching the number of lower chords of the arch rib.

[0012] Preferably, the lifting jack assembly includes at least two jacks, arranged in an inclined direction along the lower chord of the arch rib after the temporary anchoring is released.

[0013] Preferably, the lifting mechanism further includes a remote control system, which is electrically connected to the lifting jack assembly.

[0014] Preferably, the thickness of the upper sealing plate and the lower sealing plate is not less than 25 mm.

[0015] Preferably, the rigid support plate is made of steel plate with a thickness of not less than 20 mm.

[0016] The above-described unloading device for releasing temporary anchorages at the arch foot is used as follows: The anti-jacking mechanism involves pre-installing embedded steel plates before the arch seat is poured. Before releasing the temporary fixing structure, wedge-shaped pads are welded to the embedded steel plates, ensuring their tops are tightly fitted against the outer surface of the upper chord of the arch rib. One anti-jacking mechanism is installed for each upper chord of the arch rib, thus providing a reaction force to the arch rib and preventing it from tilting backward the instant the temporary fixing structure is released. The lifting device involves welding upper and lower sealing plates to the underside of the lower chord of the arch rib and the top surface of the separated temporary fixing structure, respectively, after each lower chord of the arch rib is disconnected from the temporary fixing structure. A lifting jack assembly is then placed and lifted to the corresponding height, supporting the lower chord of the arch rib. After all lower chords of the arch ribs have been disconnected from the temporary fixing structure and the lifting device is installed, the lifting jack assembly of the four chords is remotely controlled to unload synchronously, lowering the height and thus slowly releasing the arch rib.

[0017] This invention utilizes a counter-jacking mechanism to prevent the arch rib from tilting backward, and a jacking mechanism to maintain the balance of the arch rib and coordinate the slow lowering of the arch rib. This helps reduce the probability of instantaneous instability of the arch rib when the temporary fixing structure is removed from the connection support of the arch rib. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the anti-top mechanism.

[0019] Figure 2 This is a schematic diagram of the lifting mechanism.

[0020] Figure 3 This is a schematic diagram of the application state of an embodiment of the present invention.

[0021] 1. Arch rib upper chord, 2. Anti-jacking mechanism, 201. Embedded steel plate, 202. Rigid support plate, 203. Pad steel plate, 3. Arch seat, 4. Rear temporary fixing structure, 5. Wind cable fixing foundation, 6. Arch rib lower chord, 7. Lifting mechanism, 701. Upper sealing plate, 702. Lifting jack assembly, 703. Lower sealing plate, 8. Front temporary fixing structure, 9. Rear anchoring device, 10. Anchor cable, 11. Tower, 12. Lowering cable, 13. Wind cable. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0023] In the description of this utility model, it should be noted that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed during use. They are only used to facilitate the description of this utility model and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0024] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0025] A stress-relieving device for releasing temporary anchorage at the arch foot includes a counter-jacking mechanism 2 and a lifting mechanism 7, wherein: the counter-jacking mechanism 2, as... Figure 1 As shown, it includes a rigid support structure. One end of the rigid support structure can be matched and supported on the outer side of the temporary anchored position at the bottom of the upper chord of the arch rib 1 (the outer side referred to here is the side away from the lower chord of the arch rib 6), and the other end is fixed to the arch seat 3. The anti-jacking mechanism 2 forms a rigid support for the upper chord of the arch rib 1 by means of the reaction force of the arch seat 3, thereby effectively preventing the upper chord of the arch rib 1 from tilting backward; the jacking mechanism 7, as... Figure 2 As shown, it includes an upper sealing plate 701, a lower sealing plate 703, and a lifting jack assembly 702. The upper sealing plate 701 is used to match and fix the bottom surface of the lower chord of the arch rib 6. The lower sealing plate 703 is used to fix the top surface of the temporary fixing structure that is temporarily anchored below the lower chord of the arch rib 6 and has been cut and separated. The lifting jack assembly 702 is matched and fixed between the upper sealing plate 701 and the lower sealing plate 703. It should also be noted that when the connection between the lower chord of the arch rib 6 and the temporary fixing structure is released, the temporary fixing structure is generally cut to a certain length so that the lower chord of the arch rib 6 and the temporary fixing structure maintain a certain distance. When the first lower chord of the arch rib 6 is released from the temporary fixing structure, the position of the arch rib remains unchanged by the connection between the other lower chords of the arch rib 6 and the temporary fixing structure, ensuring the safety of the installation of the lifting mechanism 7. When the last lower chord of the arch rib 6 is released from the temporary fixing structure, the support of the temporary fixing structure and the lifting mechanism 7 for the other lower chords of the arch rib 6 ensures the safety of the installation of the last lifting mechanism 7.

[0026] Preferably, this embodiment provides a specific structure of a rigid support structure, which includes wedge-shaped pads. The shape of the wedge-shaped pads can better fit the arch seat 3 and the upper chord of the arch rib 1, providing support for the upper chord of the arch rib 1. The wedge-shaped pads include multiple rigid support plates 202 spaced apart. The rigid support plates 202 are arranged along the width direction of the arch rib to support the upper chord of the arch rib 1, which has a certain width. One end of each rigid support plate 202 can be matched and supported on the outer side of the temporary anchored position at the bottom end of the upper chord of the arch rib 1, and the other end is fixed to the arch seat 3. The number of wedge-shaped pads generally matches the number of upper chords of the arch rib 1, that is, each upper chord of the arch rib 1 is matched with one wedge-shaped pad for support. More preferably, in order to ensure the supporting force on the upper chord of the arch rib 1, the rigid support plates 202 are made of steel plates, and the thickness is preferably not less than 20mm.

[0027] Preferably, to facilitate the fixing of the rigid support plate 202, the anti-top mechanism also includes a pre-embedded steel plate 201. The pre-embedded steel plate 201 is pre-embedded in the arch seat 3 during the casting of the arch seat 3, and the top of the arch seat 3 is exposed and connected to the other end of the rigid support plate 202. The connection method is generally welding, which is convenient and quick.

[0028] Preferably, the anti-jacking mechanism further includes a shim steel plate 203. After the upper chord of the arch rib 1 is disconnected from the temporary fixing structure, the shim steel plate 203 is fixed to the bottom surface of the upper chord of the arch rib 1 or the top surface of the corresponding temporary fixing structure. The temporary fixing structure referred to here is the temporary fixing structure connected below the upper chord of the arch rib 1; generally, one shim steel plate 203 is provided for each upper chord of the arch rib 1. Disconnection is generally achieved by cutting, leaving a certain space between the upper chord of the arch rib 1 and the temporary fixing structure for welding the shim steel plate 203 to increase the contact area and ensure the temporary fixing structure still supports the upper chord of the arch rib 1. After the other components of the unloading device are installed and before the arch rib rotates, the shim steel plate 203 is removed so that the rotation of the upper chord of the arch rib 1 is not affected by the shim steel plate 203.

[0029] Preferably, at least two lifting mechanisms 7 are provided, matching the number of lower chord members 6 of the arch rib, that is, one lifting mechanism 7 is installed for each lower chord member 6 of the arch rib.

[0030] Preferably, combined with Figure 2 As shown, in the lifting mechanism 7, the lifting jack group 702 includes at least two jacks, which are arranged in an inclined direction along the lower chord of the arch rib 6 after the temporary anchoring is released, so as to support the lower chord of the arch rib 6 more evenly and achieve the purpose of slowly releasing the lower chord of the arch rib 6.

[0031] Preferably, the lifting mechanism 7 also includes a remote control system, which is electrically connected to the lifting jack assembly 702. The lifting and lowering of the jacks can be conveniently controlled through the remote control system to ensure the safety of construction.

[0032] Preferably, since the lifting mechanism 7 needs to bear a large load, the thickness of the upper sealing plate 701 and the lower sealing plate 703 should be not less than 25mm. In this embodiment, a steel plate with a thickness of 30mm is selected.

[0033] Preferably, to better ensure the supporting force of the rigid support plate 202 on the upper chord of the arch rib 1, the included angle between the lower side of the rigid support plate 202 and the outer side of the upper chord of the arch rib 1 should be not less than 30°, i.e., as shown below. Figure 1 As shown, the rigid support plate 202 forms an acute angle with the outer side of the upper chord of the arch rib 1. The length of contact between the top edge of the rigid support plate 202 and the outer side of the upper chord of the arch rib 1 is not less than 40mm.

[0034] Combination Figure 3 As shown, this embodiment provides a specific application scenario for the stress-relieving device. A tower 11 is pre-installed behind the arch seat 3, and a rear anchor device 9 is installed behind the tower 11. A wind-staying cable fixing foundation 5 is installed in front. The top of the tower 11 is connected to the rear anchor device 9 via an anchor cable 10. A jack is also installed on the top of the rear anchor device 9 for tensioning the anchor cable 10. A rotatable structure 400 is installed at the lower end of the arch rib segment closest to the arch seat 3 and connected to the arch seat 300. Simultaneously, temporary fixing structures are installed at the front and rear ends of the bottom of the arch rib segment, specifically connected to the upper chord 1 and lower chord 6 of the arch rib. The temporary fixing structures for fixing the upper chord 1 and lower chord 6 of the arch rib are generally separate, including a rear temporary fixing structure 4 and a front temporary fixing structure 8. Figure 3As shown, the upper chord 1 of the arch rib is connected to the rear temporary fixing structure 4, and the lower chord 6 of the arch rib is connected to the front temporary fixing structure 8. Then, the arch rib segments 700 on one side of the arch rib are assembled vertically upwards until the design length is reached. During the vertical assembly process, or after the vertical assembly is completed, a lowering cable 12 is installed behind the arch rib segment in the direction of rotation. The lowering cable 12 is connected to the tower 11 by a jack set on the top of the tower 11 and pre-tightened. A wind-guiding cable 13 is installed in front of and below the arch rib segment in the direction of rotation. The wind-guiding cable 13 is connected to the wind-guiding cable fixing foundation 5 by a jack set on the top of the wind-guiding cable fixing foundation 5 and pre-tightened. After the vertical assembly of the arch rib, the connection between the upper chord 1 and the lower chord 6 of the arch rib and the temporary fixing structure needs to be released. Then, the arch rib is rotated downwards to the design elevation under the coordinated action of the lowering cable 12 and the wind-guiding cable 13. However, at the moment when the temporary fixing structure is released from the support of the arch rib during the vertical rotation and lowering of the arch rib, a large instantaneous force will be generated, causing the lowering cable 12 and the tower 11 to be suddenly stressed. This may lead to the inability to control the cable force of the lowering system, resulting in the possibility of instantaneous instability of the arch rib. To solve this problem, this embodiment installs a force relief device at the bottom of the arch rib. The anti-jacking mechanism 2 is pre-installed with a pre-embedded steel plate 201 before the arch seat 3 is poured. Before the temporary fixing structure is released, the rigid support structure is welded to the pre-embedded steel plate 201, so that its top is tightly attached to the outer side of the upper chord of the arch rib 1. Each upper chord of the arch rib is equipped with an anti-jacking mechanism 2 to give the arch rib a reaction force and prevent the arch rib from tilting backward at the moment the temporary fixing structure is released. After the connection between the upper chord of the arch rib 1 and the rear temporary fixing structure 4 is released, if there is a matching pad steel plate 203, a pad steel plate 203 is welded to the bottom surface of the upper chord of the arch rib 1 or the top surface of the corresponding front temporary fixing structure 8. The lifting device is installed after the temporary fixing structure 4 at the rear end is removed. After each lower chord member 6 of the arch rib is disconnected from the temporary fixing structure, the upper sealing plate 701 and the lower sealing plate 703 are welded to the bottom of the lower chord member 6 of the arch rib and the top surface of the temporary fixing structure after it has been cut and separated, respectively. The lifting jack assembly 702 is then placed to lift the lower chord member 6 of the arch rib to the corresponding height. The lifting jack assembly 702 supports the lower chord member 6 of the arch rib. After all the lower chord members 6 of the arch rib are disconnected from the temporary fixing structure 8 at the front end and the lifting device is installed, all the temporary fixing structures have been removed. The lifting jack assembly 702 of the four chord members is then unloaded remotely to lower the height, thereby achieving the purpose of slowly releasing the arch rib.

[0035] This invention utilizes the anti-jacking mechanism 2 to prevent the arch rib from tilting backward, and the lifting mechanism 7 to maintain the balance of the arch rib and coordinate the slow lowering of the arch rib. This helps to reduce the probability of instantaneous instability of the arch rib when the temporary fixing structure is removed from the connection support of the arch rib.

Claims

1. A stress-relieving device for releasing temporary anchorage at the arch foot, characterized in that... include: The anti-top mechanism includes a rigid support structure, one end of which can match the outer side of the arch rib upper chord in a temporary anchoring state position, and the other end is fixed to the arch seat; The lifting mechanism includes an upper sealing plate, a lower sealing plate, and a lifting jack assembly. The upper sealing plate is used to match and fix the bottom surface of the lower chord of the arch rib. The lower sealing plate is used to fix the top surface of the temporary fixed structure that is temporarily anchored below the lower chord of the arch rib and has been cut and separated. The lifting jack assembly is matched and fixed between the upper sealing plate and the lower sealing plate.

2. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 1, characterized in that: The rigid support structure includes a wedge-shaped pad, which includes multiple rigid support plates spaced apart. One end of each rigid support plate can be matched and supported on the outer side of the temporary anchored position at the bottom of the upper chord of the arch rib, and the other end is fixed to the arch seat.

3. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 2, characterized in that: The anti-top mechanism also includes a pre-embedded steel plate, which is pre-embedded in the arch seat, with its top exposed and connected to the other end of the rigid support plate.

4. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 2 or 3, characterized in that: The anti-top mechanism also includes a padding steel plate, which is fixed to the bottom surface of the upper chord of the arch rib or the top surface of the corresponding temporary fixing structure after the upper chord of the arch rib is disconnected from the temporary fixing structure.

5. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 1, characterized in that: The lifting mechanism is provided in at least two parts, which are matched with the number of lower chord members of the arch rib.

6. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 1 or 5, characterized in that: The lifting jack assembly includes at least two jacks, arranged in an inclined direction along the lower chord of the arch rib after the temporary anchoring is released.

7. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 1 or 5, characterized in that: The lifting mechanism also includes a remote control system, which is electrically connected to the lifting jack assembly.

8. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 1, characterized in that: The thickness of the upper sealing plate and the lower sealing plate is not less than 25mm.

9. The stress-relieving device for releasing temporary anchorage at the arch foot according to claim 2, characterized in that: The rigid support plate is made of steel plate with a thickness of not less than 20mm.

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