Adjustable controllable pre-stress application bridge reinforcing device and reinforcing method

Abstract

The application discloses a bridge reinforcing device and method with adjustable and controllable prestress application, which comprises reinforcing steel plates one, anchoring steel plates one, anchoring steel plates two, reinforcing steel plates two and a prestress application device; the anchoring steel plates one and the anchoring steel plates two are repeatedly and alternately arranged along the longitudinal bridge direction and are spaced apart from each other and are connected to the outer anchoring of the bottom of the main beam; the reinforcing steel plates two and the reinforcing steel plates one are long strip-shaped steel plates; the reinforcing steel plates two are welded to the bottom surface of the anchoring steel plates one at both ends; the reinforcing steel plates one are welded to the top surface of the bottom plate of the anchoring steel plates two; one end of the reinforcing steel plates one is overlapped with the reinforcing steel plates two on one side, and the other end is welded with the reinforcing steel plates two on the other side; the prestress application device comprises channel steel columns one and two and a tension bolt which are welded to the overlapped reinforcing steel plates one and the reinforcing steel plates two; after the beam body is jacked into position and the prestress application device is locked to apply the pretightening force, the reinforcing steel plates one and the reinforcing steel plates two at the overlapped position are firmly welded; and the prestress application is adjustable and controllable.

Description

Technical Field

[0001] This invention relates to the field of bridge steel plate bonding reinforcement technology, specifically to a bridge reinforcement device and method with adjustable and controllable prestressing. This invention combines the mid-span lifting (indirect unloading) measure of the main beam to be reinforced with prestressing to apply prestress to the post-reinforcement steel plate, thereby increasing the structural stiffness, effectively improving the stress condition of the concrete main beam, and enhancing the load-bearing capacity of the main beam. Background Technology

[0002] Steel plate bonding reinforcement of the main girder of a bridge superstructure works by using adhesives and anchors to integrate the steel plate with the main girder, forming a unified load-bearing structure. This increases the stiffness of the original structure, improves the stress state of the reinforcing steel and concrete, and limits the further development of cracks, thereby strengthening and increasing the bridge's load-bearing capacity. Steel plate bonding reinforcement has become a common bridge reinforcement technique due to its convenient construction and moderate cost. (See also: [link to related text]) Figure 1 The image shows a conventional superstructure main beam reinforced with bonded steel.

[0003] The effectiveness of bonded steel plates is limited by stress hysteresis, and this hysteresis becomes more pronounced with increasing original structural load. To reduce or eliminate stress hysteresis in reinforced steel plates, methods such as unloading or prestressing are generally employed. Sometimes, a combination of unloading and prestressing is used, allowing both the old and new components of the reinforced structure to enter a working state simultaneously, thus significantly improving the overall load-bearing capacity. Prestressing methods for steel plates include heating and assisted jacking, but these all suffer from uncontrollable prestressing forces and high construction difficulty. Summary of the Invention

[0004] This invention provides a bridge reinforcement device and method with adjustable and controllable prestressing, which aims to solve the technical problem that the steel plates cannot fully perform their function when the main beam of the bridge superstructure is reinforced by bonding steel plates due to stress lag.

[0005] The technical solution of this invention is implemented as follows:

[0006] A bridge reinforcement device with adjustable and controllable prestressing, characterized in that it includes a reinforcement steel plate 1, an anchoring steel plate 2, an anchoring steel plate 3, a reinforcement steel plate 4, and a prestressing application device 5.

[0007] The anchoring steel plate 1 2 and the anchoring steel plate 2 3 are rectangular steel plate frames with open upper ends. They are arranged alternately and at intervals along the longitudinal direction of the bridge at the bottom of the main beam, and are nested outside the bottom and sides of the beam body, and are anchored to the bottom and sides of the beam body.

[0008] The second reinforcing steel plate 4 and the first reinforcing steel plate 1 are long strip-shaped steel plates arranged along the longitudinal direction of the bridge. The second reinforcing steel plate 4 is symmetrically welded to both ends of the bottom surface of the bottom plate of the first anchoring steel plate 2 along the longitudinal direction of the bridge. The first reinforcing steel plate 1 is welded to the bottom plate of the second anchoring steel plate 3 along the longitudinal direction of the bridge. The first reinforcing steel plate 1 is installed close to the bottom of the beam, with its first and last ends extending beyond the second anchoring steel plate 3. One end of the first reinforcing steel plate 4 overlaps with one side of the second reinforcing steel plate 4, and the other end is welded to the second reinforcing steel plate 4 on the other side. The second anchoring steel plate 3 and the first reinforcing steel plate 1 are together anchored to the beam.

[0009] The prestressing application device includes channel steel columns 511 and 512 welded to the bottom surfaces of the reinforcing steel plate 1 and the reinforcing steel plate 4 at the lap joint, and tie bolts 52, lock nuts and washers connecting the two channel steel columns.

[0010] After the main beam body is lifted into place and the prestressing application device is locked to apply the final prestressing force, the reinforcing steel plate 1 at the lap joint is firmly welded to the reinforcing steel plate 4.

[0011] The reinforcing steel plate 1, anchoring steel plate 2, anchoring steel plate 3, and reinforcing steel plate 4 are all bonded to the bottom of the bridge by injecting adhesive.

[0012] The bridge reinforcement device with adjustable and controllable prestressing is described above, wherein multiple reinforcing steel plates 4 and 1 are arranged symmetrically in parallel along the transverse direction of the bridge, and multiple sets of prestressing application devices are arranged in parallel accordingly.

[0013] The bridge reinforcement device with adjustable and controllable prestressing is described above, wherein the net distance between the weld point at the lap joint and the anchoring steel plate is greater than 5cm.

[0014] This invention provides a bridge reinforcement method with adjustable and controllable prestressing, comprising the aforementioned bridge reinforcement device with adjustable and controllable prestressing; wherein the construction steps include,

[0015] (1) Make basic preparations on the ground:

[0016] First, weld one end of the reinforcing steel plate 24 to the bottom of the anchoring steel plate 2 base plate; weld the reinforcing steel plate 1 to the top of the anchoring steel plate 23 base plate; weld the channel steel column to the bottom of the reinforcing steel plate 1 and the reinforcing steel plate 24 at the lap joint respectively;

[0017] (2) Construction within the reinforcement area of ​​the main beam:

[0018] After the above components are welded, anchor steel plate 2 is anchored to the main beam and glued, and anchor steel plate 3 is anchored to the main beam. Anchor steel plate 2 and anchor steel plate 3 are repeatedly and alternately installed at the bottom of the main beam along the longitudinal direction of the bridge. In order to ensure the effect of applying prestress to the steel plate, the anchor bolts at the bottom of anchor steel plate 3 are kept loose. One end of reinforcing steel plate 1 at the joint is overlapped on the top of the end of reinforcing steel plate 4 on the same side as a pre-tightening adjustment end. The other end of reinforcing steel plate 1 is overlapped on the other side of reinforcing steel plate 4 and welded firmly.

[0019] (3) Applying prestressing force: After the main beam is lifted into place at mid-span, a torque wrench is used to apply prestressing force to each of the prestressing devices, so that the reinforcing steel plate 1 is close to the bottom of the beam, and the anchor bolts at the bottom of the anchoring steel plate 3 are tightened. Then, the joint between the reinforcing steel plate 1 and the reinforcing steel plate 4 at the prestressing device is welded firmly. In order to avoid the influence of welding on the performance of the adhesive, the net distance between the welding point and the anchoring steel plate is designed to be greater than 5cm. Then, the load is unloaded step by step so that the reinforcing steel plate 1 and the reinforcing steel plate 4 are prestressed. Finally, the reinforcing steel plate 1, the reinforcing steel plate 4, the anchoring steel plate 2 and the anchoring steel plate 3 are injected with adhesive.

[0020] The beneficial effects of this invention are:

[0021] This invention provides a controllable prestressing process for reinforcing steel plates, with adjustable final prestress values. It can effectively reduce or eliminate stress hysteresis in reinforcing steel plates. Compared with conventional steel-bonded reinforcement, it effectively improves the stress state of concrete main beams, further enhances the load-bearing capacity of main beams, and significantly improves the reinforcement effect. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the existing technology for reinforcing the main beam of the superstructure with bonded steel.

[0023] Figure 2 This is a schematic elevation view of the longitudinal reinforcement structure of the box girder bottom along the bridge direction according to the present invention.

[0024] Figure 3 This is a schematic plan view of the bottom portion of the reinforced box girder along the longitudinal direction of the present invention.

[0025] Figure 4 This is a schematic elevation view of the prestressing application device of the present invention.

[0026] Figure 5 This is a schematic diagram of the channel steel column structure of the present invention.

[0027] Figure 6 This is a schematic diagram of the second structure of the channel steel column of the present invention.

[0028] Explanation of the attached drawing numbers:

[0029] 1. Reinforcing steel plate 1; 2. Anchoring steel plate 2; 3. Reinforcing steel plate 2; 4. Prestressing application device; 5. Channel steel column 51; 511. Channel steel column 1; 512. Channel steel column 2; 52. Tie bolt; 53. Nut; 54. Washer; 100. Main beam; 101. Welding after pre-tightening; 102. Adhesive for steel bonding;

[0030] Figure 1 In the middle, there are continuous irregular plate 201, fixed anchor bolt 202, steel plate 203, and steel adhesive 102 (injected between the bottom of the beam and the steel plate). Detailed Implementation

[0031] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0032] See Figure 2 , 3 As shown, the present invention provides a bridge reinforcement device for adjustable and controllable prestressing, comprising a reinforcement steel plate 1, an anchoring steel plate 2, an anchoring steel plate 3, a reinforcement steel plate 4, and a prestressing application device 5.

[0033] The anchoring steel plate 1 2 and the anchoring steel plate 2 3 are rectangular steel plate frames with open upper ends. They are arranged alternately and at intervals along the longitudinal direction of the bridge at the bottom of the main beam, and are nested outside the bottom and sides of the beam body, and are anchored to the bottom and sides of the beam body.

[0034] The second reinforcing steel plate 4 and the first reinforcing steel plate 1 are long strip-shaped steel plates arranged along the longitudinal direction of the bridge. The second reinforcing steel plate 4 is symmetrically welded to both ends of the bottom surface of the bottom plate of the first anchoring steel plate 2 along the longitudinal direction of the bridge. The first reinforcing steel plate 1 is welded to the bottom plate of the second anchoring steel plate 3 along the longitudinal direction of the bridge. The first reinforcing steel plate 1 is installed close to the bottom of the beam, with its first and last ends extending beyond the ends of the second anchoring steel plate 3. One end of the first reinforcing steel plate 4 overlaps with one side of the second reinforcing steel plate 4, and the other end is welded to the second reinforcing steel plate 4 on the other side. The second anchoring steel plate 3 and the first reinforcing steel plate 1 are together anchored to the beam.

[0035] The prestressing application device includes channel steel columns 511 and 512, respectively welded to the bottom surfaces of the reinforcing steel plate 1 and the reinforcing steel plate 4 at the lap joint, and tie bolts 52, lock nuts, and washers connecting the two channel steel columns; see also Figure 4-6 As shown;

[0036] After the main beam is lifted into place and the prestressing device is locked to apply the final prestressing force, one end of the reinforcing steel plate 1 at the lap joint is firmly welded to the reinforcing steel plate 4; the anchoring bolts of the anchoring steel plate 3 are tightened.

[0037] The reinforcing steel plate 1, anchoring steel plate 2, anchoring steel plate 3, and reinforcing steel plate 4 are all bonded to the bottom of the bridge by injecting adhesive.

[0038] The bridge reinforcement device with adjustable and controllable prestressing is described above, wherein multiple reinforcing steel plates 4 and 1 are arranged symmetrically in parallel along the transverse direction of the bridge, and multiple sets of prestressing application devices are arranged in parallel accordingly.

[0039] The bridge reinforcement device with adjustable and controllable prestressing is described above, wherein the net distance between the weld point at the lap joint and the anchoring steel plate is greater than 5cm.

[0040] This invention provides a bridge reinforcement method with adjustable and controllable prestressing, comprising the aforementioned bridge reinforcement device with adjustable and controllable prestressing; wherein the construction steps include,

[0041] (1) Make basic preparations on the ground:

[0042] First, weld one end of the reinforcing steel plate 24 to the bottom of the anchoring steel plate 2 base plate; weld the reinforcing steel plate 1 to the top of the anchoring steel plate 23 base plate; weld the channel steel column to the bottom of the reinforcing steel plate 1 and the reinforcing steel plate 24 at the lap joint respectively;

[0043] (2) Construction within the reinforcement area of ​​the main beam:

[0044] After the above components are welded, anchor steel plate 2 is anchored to the main beam and glued, and anchor steel plate 3 is anchored to the main beam. Anchor steel plate 2 and anchor steel plate 3 are repeatedly and alternately installed at the bottom of the main beam along the longitudinal direction of the bridge. In order to ensure the effect of applying prestress to the steel plate, the anchor bolts at the bottom of anchor steel plate 3 are kept loose. One end of reinforcing steel plate 1 at the joint is overlapped on the top of the end of reinforcing steel plate 4 on the same side as a pre-tightening adjustment end. The other end of reinforcing steel plate 1 is overlapped on the other side of reinforcing steel plate 4 and welded firmly.

[0045] (3) Applying prestressing force: After the main beam is lifted into place at mid-span, a torque wrench is used to apply prestressing force to each of the prestressing devices, so that the reinforcing steel plate 1 is close to the bottom of the beam, and the anchor bolts at the bottom of the anchoring steel plate 3 are tightened. Then, the joint between the reinforcing steel plate 1 and the reinforcing steel plate 4 at the prestressing device is welded firmly. In order to avoid the influence of welding on the performance of the adhesive, the net distance between the welding point and the anchoring steel plate is designed to be greater than 5cm. Then, the load is unloaded step by step so that the reinforcing steel plate 1 and the reinforcing steel plate 4 are prestressed. Finally, the reinforcing steel plate 1, the reinforcing steel plate 4, the anchoring steel plate 2 and the anchoring steel plate 3 are injected with adhesive.

[0046] The steel bonding adhesive used in this invention is a traditional steel bonding adhesive.

[0047] Example 1

[0048] The emergency support and reinforcement project for the D ramp of a certain overpass was carried out according to the construction steps of the bridge reinforcement method described in this invention; wherein,

[0049] The jacking process for applying prestress to the steel plate is as follows:

[0050] 1) Steel plate reinforcement at the mid-span of the main beams in the fourth and fifth spans of the bridge;

[0051] 2) Temporarily lift the bridge at the mid-span of the fourth and fifth spans. After the steel plates are reinforced, release the jacking force to obtain the prestress of the reinforced steel plates.

[0052] The bottom width of the box girder of the bridge is 5m. Sixteen reinforcing steel plates (1) are arranged at equal intervals along the transverse direction. The plates are 15cm wide and 5m long. Seven groups (112 plates in total) are arranged along the longitudinal direction in the fourth span and five groups (80 plates in total) are arranged along the longitudinal direction in the fifth span. The reinforcing steel plate (4) is 15cm wide and 40cm long. The anchoring steel plate (2) is arranged at 5m intervals along the longitudinal direction and is 50cm wide. The anchoring steel plate (3) is arranged between two adjacent anchoring steel plates (2) and is 25cm wide.

Claims

1. An adjustable controllably applied pre-stressing bridge reinforcement device, characterised in that, The application relates to a bridge beam reinforcing device, which comprises a reinforcing steel plate one (1), an anchoring steel plate one (2), an anchoring steel plate two (3), a reinforcing steel plate two (4) and a prestress applying device (5). The anchoring steel plate one (2) and the anchoring steel plate two (3) are rectangular steel plate frames with open upper ends, are arranged in the longitudinal bridge direction repeatedly and alternately and are spaced apart from each other on the bottom of the main beam, and are embedded in the bottom and the lateral surface of the beam body and are anchored and connected with the bottom and the lateral surface of the beam body. The reinforcing steel plate two (4) and the reinforcing steel plate one (1) are long strip-shaped steel plates arranged in the longitudinal bridge direction, the reinforcing steel plate two (4) is located below the reinforcing steel plate one (1), the reinforcing steel plate two (4) is symmetrically welded on the bottom of the bottom plate of the anchoring steel plate one (2) in the longitudinal bridge direction, the reinforcing steel plate one (1) is welded on the top of the bottom plate of the anchoring steel plate two (3) in the longitudinal bridge direction, the reinforcing steel plate one (1) is closely arranged on the bottom of the beam body, the head and tail ends of the reinforcing steel plate one (1) extend out of the anchoring steel plate two (3), one end of the reinforcing steel plate one (1) is overlapped with the reinforcing steel plate two (4) on one side, and the other end of the reinforcing steel plate one (1) is welded with the reinforcing steel plate two (4) on the other side, the anchoring steel plate two (3) is anchored and connected with the beam body together with the reinforcing steel plate one (1). The prestress applying device comprises a channel steel column one (511) and a channel steel column two (512) welded on the bottom of the reinforcing steel plate one (1) and the reinforcing steel plate two (4) respectively, and a tension bolt (52), a locking nut and a gasket connecting the two channel steel columns. After the beam body of the main beam is lifted into position and the prestress applying device is locked and the final prestress is applied, the reinforcing steel plate one (1) and the reinforcing steel plate two (4) at the overlapping position are firmly welded. The reinforcing steel plate one (1), the anchoring steel plate one (2), the anchoring steel plate two (3) and the reinforcing steel plate two (4) are all adhered to the bottom of the bridge body by pouring steel adhesive.

2. A bridge reinforcement device capable of adjustable and controllable pre-stress application as claimed in claim 1, characterized in that, The reinforcing steel plate two (4) and the reinforcing steel plate one (1) are arranged in multiple parallel and symmetric strips in the transverse bridge direction, and the prestress applying device is arranged in multiple groups correspondingly.

3. A bridge reinforcement device capable of adjustable and controllable pre-stress application as claimed in claim 1, characterized in that, The distance between the welding points at the overlapping position and the anchoring steel plate is greater than 5 cm.

4. A bridge reinforcement method of adjustable and controllable pre-stress application, comprising the bridge reinforcement device of adjustable and controllable pre-stress application according to claim 1; characterized in that, The construction steps comprise (1) preparing the foundation on the ground: First, one end of the reinforcing steel plate two (4) is welded on the bottom of the bottom plate of the anchoring steel plate one (2), the reinforcing steel plate one (1) is welded on the top of the bottom plate of the anchoring steel plate two (3), and the channel steel columns are welded on the bottom of the reinforcing steel plate one (1) and the reinforcing steel plate two (4) at the overlapping position respectively; (2) constructing in the reinforcing range of the main beam: After the welding of the above components is completed, the anchoring steel plate one (2) is anchored and glued with the main beam, the anchoring steel plate two (3) is anchored with the main beam, the anchoring steel plate one (2) and the anchoring steel plate two (3) are repeatedly and alternately arranged on the bottom of the main beam in the longitudinal bridge direction, the anchoring bolt at the bottom of the anchoring steel plate two (3) is kept in a relaxed state to ensure the prestress applying effect of the steel plate, one end of the reinforcing steel plate one (1) at the overlapping position is overlapped on the top of the end of the reinforcing steel plate two (4) on the same side as the prestress adjusting end, and the other end of the reinforcing steel plate one (1) is overlapped on the top of the reinforcing steel plate two (4) on the other side and is firmly welded. (3) applying pre-tightening force: after the main beam is jacked to the position, pre-tightening force is applied to each of the pre-stress applying devices by a torque wrench, so that the reinforcing steel plate one (1) is close to the beam bottom, the anchor bolts at the bottom of the reinforcing steel plate two (3) are tightened, then the reinforcing steel plate one (1) and the reinforcing steel plate two (4) at the installation position of the pre-stress applying device are welded firmly, in order to avoid the influence on the performance of the steel bonding glue during welding, the distance between the welding point and the anchor steel plate is greater than 5 cm, then the pre-stress is obtained by gradually unloading the reinforcing steel plate one (1) and the reinforcing steel plate two (4), and finally the reinforcing steel plate one (1), the reinforcing steel plate two (4), the anchor steel plate one (2) and the anchor steel plate two (3) are glued.

Images