Auxiliary fixing device of steel cofferdam

Abstract

The utility model belongs to the technical field of bridge construction, and particularly relates to an auxiliary fixing device of a steel cofferdam. Comprising a fixing assembly, a stress assembly and a tensioning assembly connected with the fixing assembly and the stress assembly. The stress assembly comprises a pre-embedded assembly and a counter-force seat; the counter-force base is composed of a top plate and a supporting plate, so that a tensioning space capable of containing a tensioning assembly is formed between the supporting plate and the top plate. The top plate is provided with a first through hole allowing the tensioning assembly to pass through, and the bottom of the supporting plate is fixedly connected with the embedded assembly. Through cooperation of the three components, the water leakage risk caused by the fact that the steel cofferdam and the concrete bottom plate cannot be completely welded is reduced, and the overall impact resistance of the steel cofferdam is enhanced. The device is simple in structure, convenient to install, low in cost and beneficial to popularization and application in production practice, and the working efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of bridge construction and construction, and particularly relates to an auxiliary fixing device for a steel cofferdam. BACKGROUND

[0002] The bottomed steel box, also known as a steel hanging box, is a temporary water-blocking structure designed for deep-water high-pile pile cap construction and is widely used in the foundation construction of large-span deep-water bridges. Since the cofferdam side wall and the bottom plate can be directly welded, the water-blocking effect is good. However, with the development of bridge construction technology, firstly, the construction of the hanging box is seriously affected by environmental factors, and the effective construction operation time is easily reduced; secondly, the concrete bottom plate can be used as a permanent corrosion-resistant layer, especially in large projects, the cost advantage of the concrete bottom plate is obvious, and many projects have begun to use prefabricated concrete bottom plates instead of steel bottom plates for cofferdam construction. However, due to the difference in material between the steel cofferdam and the concrete bottom plate, how to improve the waterproof effect has become a problem to be solved.

[0003] The reinforcement of the steel cofferdam and the bottom plate can have multiple ways, for example, the patent 202222870833.6 discloses a steel cofferdam, which has a positioning groove pre-set on the bottom plate and a positioning plate set at the lower part of the steel cofferdam. During installation, the positioning plate is installed in the positioning groove, which facilitates positioning during installation and further enhances the lateral stability of the steel cofferdam. The connection method between the concrete bottom plate and the steel cofferdam side wall is usually to weld the steel plate pre-buried in the concrete bottom plate with the steel cofferdam side wall. However, even if a positioning groove is set on the concrete bottom plate, due to the limitation of construction difficulty, the depth of the positioning groove will not be too deep, and even if a steel plate is pre-buried in the positioning groove, since the pre-buried steel plate is not a through drain, the steel cofferdam is intermittently welded on the concrete bottom plate, so the waterproof effect is still not good at the un-welded parts.

[0004] As described in the "Design and Construction Key Technology of Prefabricated Concrete Bottom Plate Steel Hanging Box Cofferdam" published in the 11th issue of "Fujian Transportation Science and Technology" in 2021, limit blocks are first set on the prefabricated concrete bottom plate, the wall plate is installed at the appropriate position and temporarily welded with the steel casing, and the wall plate and the bottom plate are sealed by filling the foaming agent. Although this technical solution can effectively limit the steel cofferdam, the wall plate and the bottom plate are only attached by the self-weight of the wall plate, and due to the difference in construction environment, the gap between the steel cofferdam and the concrete bottom plate is easily enlarged under the impact of water waves. Therefore, the impact resistance and waterproof effect of the cofferdam need to be improved. UTILITY MODEL CONTENTS

[0005] The utility model is to overcome the poor waterproof measure implementation effect between the steel cofferdam and the concrete bottom plate in the prior art, the defect that the steel cofferdam is easily leaked at the joint with the concrete bottom plate under the impact of water waves, and provides an auxiliary fixing device for a steel cofferdam to overcome the above-mentioned defects.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0007] An auxiliary fixing device for a steel cofferdam includes:

[0008] Fixed components, load-bearing components, and tensioning components that connect the fixed components and the load-bearing components;

[0009] The force-bearing component includes a pre-embedded component and a reaction seat fixedly connected to the pre-embedded component;

[0010] The reaction seat includes a top plate and at least two support plates that are vertically fixed to the lower end of the top plate, such that a tensioning space is formed between the support plates and the top plate to accommodate the tensioning assembly.

[0011] The top plate is provided with a first through hole that allows the tensioning component to pass through, and the bottom of the support plate is fixedly connected to the pre-embedded component.

[0012] In traditional precast concrete cofferdam construction, the concrete base slab is typically divided into several sections. Therefore, the construction steps can be summarized as follows: transporting the precast concrete base slab to the high-pile platform for assembly; connecting and fixing the cofferdam side panels to the concrete base slab; waterproofing the gaps between the side panels and the base slab; and lowering the cofferdam and base slab together to the target position. In the fixing step, steel components pre-embedded in the concrete base slab are usually used to connect the steel cofferdam by welding or bolting, followed by waterproofing treatment at the joints using waterproofing strips or expanding foam. However, the more steel components installed in the concrete base slab, the greater the impact on the overall strength of the concrete base slab. Therefore, the welding points between the steel cofferdam sidewalls and the concrete base slab are intermittent and limited. Consequently, when the cofferdam is impacted, the areas between the sidewalls and the base slab that are not welded using pre-embedded components become weak points, significantly reducing the waterproofing effectiveness of both rubber seals and expanding foam.

[0013] This invention involves pre-embedding components on a concrete base slab as load-bearing fulcrums. These components are primarily located at the joints between the cofferdam side plates and at weak points where the side plates are not welded to the concrete base slab; the specific locations are determined based on the actual engineering conditions. Reaction seats are then installed on the pre-embedding components to connect to the tensioning components. The support plates of the reaction seats can be fixed to the pre-embedding components by welding. This invention also requires the installation of fixing components on the steel cofferdam, and finally, the tensioning components connect the fixing components and the load-bearing components to achieve tension between the steel cofferdam and the concrete base slab. In practice, if the steel cofferdam has transverse ribs, holes can be drilled in the transverse ribs to serve as fixing components. In practice, to ensure the stability and tension strength of the overall device, the fixing components are usually located in the middle of the cofferdam, and the length of the tensioning components should preferably not exceed 5 meters.

[0014] As a preferred, the counterforce seat further comprises reinforcing plates for reinforcing the top plate and the support plate. Since the tension of the tensioning assembly is borne by the top plate, several reinforcing plates can be arranged between the top plate and the support plate, which can prevent the counterforce seat from deforming, and the reinforcing plates can be welded with the embedded assembly as new welding points to prevent the counterforce seat from separating from the embedded assembly due to excessive tension.

[0015] As a preferred, the first through hole is provided with a U-shaped opening. Due to the limitation of the volume of the counterforce seat, the tensioning space may not be convenient for the tensioning of the tensioning assembly, and therefore the through hole on the top plate can be arranged in a U shape, so that the tensioning assembly can enter and exit the counterforce seat from the side, facilitating installation and disassembly.

[0016] As a preferred, the embedded assembly comprises an embedded steel plate and embedded steel bars welded perpendicularly to the embedded steel plate. The lower end embedded steel bars are embedded in the concrete, and resist the pulling force of the upper end tension rod through the frictional resistance between the steel bars and the concrete. The number of steel bars can be adjusted according to the size of the force, and the number of steel bars can be increased for large force and reduced for small force.

[0017] As a further preferred, the area of the top plate is greater than or equal to the area of the embedded steel plate. Since the top plate bears a large tension, in practice the top plate should be larger than the embedded steel plate below to ensure overall strength, and a larger top plate can also be provided with a larger reinforcing plate to further improve the anti-deformation performance.

[0018] As a preferred, the fixing assembly comprises a cantilevered steel plate welded to the steel cofferdam, so that the cantilevered steel plate is perpendicular to the tensioning assembly, and the cantilevered steel plate is provided with a second through hole through which the tensioning assembly passes. If the steel cofferdam is provided with a horizontal rib, a hole can be directly punched in the horizontal rib to use it as a cantilevered steel plate.

[0019] As a further preferred, the fixing assembly further comprises a reinforcing plate welded perpendicularly to the cantilevered steel plate. The reinforcing plate is arranged below the cantilevered steel plate and can be welded with the side wall of the steel cofferdam to further prevent the cantilevered steel plate from deforming under stress.

[0020] As a preferred, the tensioning assembly comprises a tension rod and bolts bolted at both ends of the tension rod. In practice, the diameter of the tension rod is preferably above 32 mm, and the bolt is preferably a precision rolled nut.

[0021] As a further preferred, the tensioning assembly further comprises a gusset plate arranged between the bolt and the first through hole and the second through hole, respectively. By adding a gusset plate between the bolt and the through hole, the stress area is increased to prevent local deformation of the device.

[0022] In another aspect, the utility model discloses a kind of connecting structure of steel cofferdam and concrete bottom plate, including concrete bottom plate, and the steel cofferdam of being set on concrete bottom plate, the steel cofferdam is connected with concrete bottom plate by the auxiliary fixing device, the fixed subassembly is detachably connected with steel cofferdam, the stress subassembly is fixedly connected with concrete bottom plate, the fixed subassembly is connected with stress subassembly by tensioning component.In practice, to facilitate the further construction inside cofferdam, the auxiliary fixing device is preferably set in the side of cofferdam outside and water contact.

[0023] Therefore, the utility model has the following beneficial effects:

[0024] (1) the utility model discloses three-component assemblies, and steel cofferdam side wall and concrete bottom plate are closely adhered, and the defect of water leakage risk caused by the incomplete welding of side wall and bottom plate is made up, and the waterproof effect of weak position is further improved on the basis of traditional waterproof treatment such as rubber strip;

[0025] (2) the device of the utility model passes through longer tensioning component, and the stress of upper part of steel cofferdam is transmitted to lower pre-embedded component, and the overall impact resistance of steel cofferdam is strengthened;

[0026] (3) the utility model has simple structure, and main part can be obtained by welding, and installation is more convenient, improve work efficiency, and cost is lower, be favorable to the popularization and application in production practice. BRIEF DESCRIPTION OF DRAWINGS

[0027] Fig. 1 It is the installation schematic drawing of the auxiliary fixing device of the utility model.

[0028] Fig. 2 It is the schematic diagram of counterforce seat of the utility model.

[0029] Fig. 3 It is the front view of counterforce seat of the utility model.

[0030] Fig. 4 It is the plan view of counterforce seat of the utility model.

[0031] Fig. 5 It is the connection schematic diagram of stress subassembly and tensioning component of the utility model.

[0032] Fig. 6 It is the installation schematic drawing of fixed device of the utility model.

[0033] In the diagram: 1. Concrete base slab; 2. Steel cofferdam; 10. Fixing component; 11. Cantilever steel plate; 12. Second through hole; 13. Reinforcing plate; 20. Load-bearing component; 21. Embedded component; 22. Reaction seat; 23. Top plate; 24. Support plate; 25. Tensioning space; 26. First through hole; 27. Reinforcing rib plate; 28. Embedded steel plate; 29. ​​Embedded steel bar; 30. Tensioning component; 31. Tie rod; 32. Bolt; 33. Washer plate. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. 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 scope of protection of the present invention.

[0035] like Figs. 1-6 As shown, a steel cofferdam 2 is vertically placed on a concrete base slab 1. The auxiliary fixing device of this utility model is set perpendicular to the concrete base slab 1 on the outside of the steel cofferdam 2. The auxiliary fixing device mainly consists of a fixing component 10, a force-bearing component 20, and a tensioning component 30. A cantilevered steel plate 11 parallel to the concrete base slab 1 is welded to the middle of the steel cofferdam 2. The cantilevered steel plate 11 is also provided with a second through hole 12 through which a tie rod 31 can pass. An embedded component 21 is set on the concrete base slab 1 directly below the cantilevered steel plate 11. It includes nine embedded steel bars 29 embedded in the concrete, and an embedded steel plate 28 welded to the embedded steel bars 29 and exposed on the concrete base slab 1. The force-bearing component also includes a pre-formed reaction seat 22, which is welded together from a top plate 23 and two support plates 24 that are vertically fixed to the lower end of the top plate 23. A tensioning space 25 is formed between them to accommodate bolts 32 and pads 33, and the area of ​​the top plate 23 is larger than that of the embedded steel plate 28. Simultaneously, two reinforcing ribs 27 are respectively provided on both sides away from the tensioning space 25 between the top plate 23 and the support plates 24. The reinforcing ribs 27 are welded together with the support plates 24 onto the embedded steel plate 28. The two ends of the tie rod 31 of the tensioning component 30 pass through the first through hole 26 at the lower end and the second through hole 12 at the upper end, respectively, and are then connected to the fixing component 10 and the force-bearing component 20 via the pads 33 at both ends and the bolts 32. The first through hole 26 has a U-shaped opening.

[0036] The usage process of this embodiment is as follows:

[0037] like Figs. 1-6When the steel cofferdam 2 moves to the predetermined position on the concrete bottom plate 1, the welding of the steel cofferdam and the embedded part is first carried out, and the auxiliary fixing device of the utility model is arranged at the welding discontinuous point and other easy water leakage positions. After the steel cofferdam 2 and the concrete bottom plate 1 are leveled by mortar, the waterproof rubber strips are pasted at the joints, and then the installation of the fixing device is carried out. First, the counterforce seat 22 is welded on the embedded steel plate 29, so that the support plate 24 and the reinforcing rib plate 27 are welded with the embedded steel plate. The cantilever steel plate 11 is welded in the middle of the steel cofferdam 2. The spacer plate 33 is first sleeved on the lower end of the pull rod 31 and screwed into part of the bolt 32, and then the tensioning assembly is placed into the counterforce seat 22 through the U-shaped opening on the top plate 23, so as to avoid the tightening operation in the narrow space of the tensioning space 25. The pull rod 31 passes through the second through hole 12 and is sleeved with the spacer plate 33 and the bolt 32 at the upper end, and the reinforcing plate 13 is welded below the cantilever steel plate 11. The pull rod 31 is tensioned by using the through center jack at the upper end according to the designed tensioning force, and the bolt 32 at the upper end is fastened, and the installation of the auxiliary fixing device of the utility model patent is completed. When the steel cofferdam needs to be disassembled after the construction of the bridge pile foundation is completed, the fixed assembly 10 at the low tide position is exposed to the water surface, the bolt 32 at the upper end is disassembled, and the pull rod 31 is sunk by a distance, so that the pull rod can be moved out from the side through the U-shaped opening, thereby simply and quickly completing the disassembly of the device.

Claims

1. An auxiliary fixing device for a steel cofferdam, characterized in that, The utility model relates to a kind of steel cofferdams, including: fixed component (10), force component (20), and the tensioning component (30) connecting fixed component (10) and force component (20);The force component (20) includes embedded component (21), and counterforce seat (22) is fixedly connected with embedded component (21);The counterforce seat (22) includes a top plate (23), and at least two pieces of support plate (24) are vertically fixed with the lower end of top plate (23), so that the support plate (24) and top plate (23) form the tensioning space (25) capable of accommodating tensioning component (30) between;The top plate (23) is equipped with the first through-hole (26) capable of allowing tensioning component (30) to pass, and the bottom of the support plate (24) is fixedly connected with the embedded component (21). The counterforce seat (22) further includes reinforcing rib plate (27) for reinforcing top plate (23) and support plate (24). The first through-hole (26) is provided with U-shaped opening. The embedded component (21) includes embedded steel plate (28), and embedded steel bar (29) is vertically welded with embedded steel plate (28). The area of the top plate (23) is greater than or equal to the area of the embedded steel plate (28).

2. The auxiliary fixing device of a steel cofferdam according to claim 1, characterized in that: The fixed component (10) includes cantilevered steel plate (11) welded and fixed on steel cofferdam (2), so that cantilevered steel plate (11) and tensioning component (30) are perpendicular to each other, and the second through-hole (12) capable of passing through tensioning component (30) is provided on the cantilevered steel plate (11).

3. The auxiliary fixing device of a steel cofferdam according to claim 1, characterized in that: The fixed component (10) further includes reinforcing plate (13) welded and fixed perpendicularly to cantilevered steel plate (11).

4. The auxiliary fixing device of a steel cofferdam according to claim 1, characterized in that: The tensioning component (30) includes pull rod (31) and bolt (32) bolted at both ends of pull rod (31).

5. The auxiliary fixing device of a steel cofferdam according to claim 4, characterized in that: The tensioning component (30) further includes spacer plate (33), and the spacer plate (33) is respectively arranged between bolt (32) and first through-hole (26) and second through-hole (12).

6. The auxiliary fixing device of a steel cofferdam according to claim 1, characterized in that: ​ 7. The auxiliary fixing device of a steel cofferdam according to claim 5, characterized in that: ​ 8. The auxiliary fixing device of a steel cofferdam according to claim 1, characterized in that: ​ 9. The auxiliary fixing device of a steel cofferdam according to claim 8, characterized in that: ​

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