Prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam and construction method

Abstract

The present invention discloses a prefabricated beam and slab bottom-sealed double-wall steel-concrete combined hanging box cofferdam and construction method, which mainly includes the following steps: assembling and positioning the prefabricated double-wall steel cofferdam on site, installing the steel bottom plate by using the lifting system and splicing it into a bottom-sealed concrete bottom plate; hoisting and connecting multiple prefabricated double-wall steel cofferdam units one by one through precise alignment and fixing technology, installing water stop belts and purlins during the process to strengthen the structural stability; using fine-rolled threaded steel to reinforce the vertical adjacent cofferdams; adjusting the bottom plate height, repeating the installation until a complete steel hanging box structure is formed; after setting temporary support, sinking the steel hanging box by water injection to facilitate underwater concrete operations; finally draining and removing the lifting system to complete the cofferdam construction. The present invention adopts the prefabricated bottom-sealed concrete bottom plate steel cofferdam construction technology, reduces the amount of bottom-sealed concrete, effectively shortens the construction period, and makes the cofferdam bottom seal safe and reliable while ensuring the quality of the project, while greatly improving the construction efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of steel cofferdam construction, and in particular to a prefabricated beam and slab bottom-sealed double-wall steel-concrete combined hanging box cofferdam and a construction method. Background Art

[0002] With the rapid advancement of science and technology, bridge construction technology is also constantly breaking through and innovating, especially in the field of deep-water foundation cofferdam construction, the technical level at home and abroad is experiencing a significant improvement. However, the current research focus is mostly on the bridge foundation cofferdam technology with on-site cast-in-place bottom concrete slab as the core. This process involves a series of processes such as building cofferdams, dredging, laying the bottom layer, installing formwork, tying steel mesh, pouring concrete and maintenance. This technology depends on on-site operating conditions and can be flexibly adjusted according to actual conditions, but it is also restricted by multiple factors such as construction environment, weather, resource scheduling, and has great limitations. Although this technology is widely used, it has problems such as long construction period, susceptibility to weather, high difficulty in quality control, large consumption of material resources, significant environmental impact and many safety hazards, which is very unfavorable for construction efficiency, cost control and environmental protection. Therefore, how to effectively overcome the above shortcomings and promote the modernization and sustainable development of bridge construction technology has become a key issue that needs to be overcome in engineering practice. Summary of the invention

[0003] The purpose of the present invention is to provide a prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam and a construction method.

[0004] The object of the present invention is achieved through the following technical scheme: A construction method of a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam comprises the following steps:

[0005] S1: Produce and assemble prefabricated double-wall steel cofferdams; and transport the double-wall steel cofferdams to the construction site;

[0006] S2: Install a lifting system on the steel casing, lift the steel bottom plate to the installation position, connect the lifting system to the steel bottom plate and adjust the steel bottom plate to the first height position, and splice adjacent steel bottom plates to obtain a prefabricated bottom-sealed concrete bottom plate;

[0007] S3: hoisting the first prefabricated double-walled steel cofferdam to the prefabricated bottom concrete slab and connecting and fixing it to the prefabricated bottom concrete slab; laying a water stop strip on the prefabricated double-walled steel cofferdam; hoisting the purlin to the inner side of the prefabricated double-walled steel cofferdam and fixing it to the corbel on the inner plate of the prefabricated double-walled steel cofferdam;

[0008] S4: hoist the second prefabricated double-walled steel cofferdam to a set height above the prefabricated bottom concrete slab and stop, adjust the angle of the current prefabricated double-walled steel cofferdam so that the positioning rod on the current prefabricated double-walled steel cofferdam is aligned with the guide rail on the lower prefabricated double-walled steel cofferdam, rotate the guide rail on the lower prefabricated double-walled steel cofferdam so that the positioning rod on the current prefabricated double-walled steel cofferdam is inserted into the guide groove on the guide rail; then continue to lower the current prefabricated double-walled steel cofferdam and dock it with the prefabricated double-walled steel cofferdam below; lay a water stop strip above the current prefabricated double-walled steel cofferdam; hoist the purlin to the inner side of the current prefabricated double-walled steel cofferdam and fix it to the bracket on the inner plate of the prefabricated double-walled steel cofferdam;

[0009] S5: Install the finished rolled threaded steel bar between two vertically adjacent prefabricated double-walled steel cofferdams;

[0010] S6: adjusting the prefabricated bottom sealing concrete bottom plate to the second height position through the lifting system;

[0011] S7: Repeat steps S4 and S5 to complete the installation of the third prefabricated double-walled steel cofferdam; the prefabricated double-walled steel cofferdam and the prefabricated bottom concrete slab together form a steel hanging box; a temporary support is set below the prefabricated bottom concrete slab, water is injected into the steel hanging box and the steel hanging box is lowered to contact with the temporary support through the lifting system; underwater concrete construction work is performed below the steel hanging box;

[0012] S8: Pump out the water in the steel hanging box and dismantle the lifting system.

[0013] Preferably, the prefabricated double-walled steel cofferdam includes an outer plate and an inner plate, and a connecting rod is provided between the outer plate and the inner plate; a reserved hole is provided on the connecting rod; the two ends of the fine-rolled threaded steel bar respectively pass through the reserved holes on the connecting rods on two vertically adjacent prefabricated double-walled steel cofferdams, and the two ends of the fine-rolled threaded steel bar are respectively fastened to the connecting rods by gaskets and anchors; when the fine-rolled threaded steel bar is fastened, one end of the fine-rolled threaded steel bar is connected to a jack, and a tensile force is applied to the fine-rolled threaded steel bar by the jack to tension the fine-rolled threaded steel bar.

[0014] Preferably, in step S2, when installing the lifting system on the steel casing, the method is as follows:

[0015] A support plate is installed on the top of the steel casing, and a jack is installed on the support plate. The jack is provided with an extended fine-rolled threaded steel bar, and the extended fine-rolled threaded steel bar is connected to the steel bottom plate.

[0016] Preferably, the steel bottom plate is provided with a guide positioning wheel, the steel bottom plate is provided with a shoulder pole beam, and the shoulder pole beam is provided with a lifting ring; when the height of the bottom steel bottom plate is adjusted by the lifting system, the guide positioning wheel contacts the outer wall of the steel casing.

[0017] Preferably, square steel pipes are welded on the inner plate of the double-walled steel cofferdam, and the square steel pipes are welded to the upper and lower sides of the inner plate; the square steel pipes located on the upper side are higher than the upper end of the inner plate to form a protrusion at the upper end of the inner plate, and the square steel pipes located on the lower side are higher than the lower end of the inner plate to form an embedded area between the square steel pipe on the lower side and the lower end of the inner plate; the protrusion on the current double-walled steel cofferdam is embedded in the embedded area on the upper double-walled steel cofferdam.

[0018] Preferably, when the prefabricated double-walled steel cofferdam is hoisted, one end of the sling is connected to the prefabricated double-walled steel cofferdam, and the other end of the sling is connected to the lifting equipment; a level adjustment piece is provided on the sling; an inclinometer is installed on the prefabricated double-walled steel cofferdam; the levelness of the prefabricated double-walled steel cofferdam is monitored by the inclinometer; when the levelness of the prefabricated double-walled steel cofferdam exceeds a preset range, the levelness of the prefabricated double-walled steel cofferdam is adjusted by the level adjustment piece.

[0019] Preferably, the level adjustment member comprises an adjustment member body, a sling through hole is provided on the adjustment member body, a fixed roller is provided on one side of the sling through hole, a movable roller is provided on the other side of the sling through hole, and the sling passes between the fixed roller and the movable roller; the fixed roller and the movable roller are arranged alternately;

[0020] A guide hole corresponding to the movable roller is provided on one side of the sling through hole, a slider is slidably connected in the guide hole, the movable roller is connected to one end of the slider, and the other end of the slider is an arc surface; a transmission member guide groove is provided on the side of the guide hole away from the sling through hole, a transmission member is slidably connected in the transmission member guide groove, and an inclined groove corresponding to the slider is provided on the transmission member;

[0021] The inclined surface groove includes a groove bottom surface and inclined surfaces at both ends of the inclined surface groove, the lower end of the inclined surface is connected to the groove bottom surface, and the higher end of the inclined surface is connected to the outer plane of the transmission member; the length between the higher ends of the inclined surfaces at both ends of the inclined surface groove is equal to the length of the groove bottom surface on the adjacent inclined surface groove below;

[0022] A driving device for driving the transmission member to move is also provided on the adjusting member body; the driving device drives the transmission member to move along the inclined surface on the inclined surface groove to drive the slider and the movable roller to move axially along the guide hole; by changing the position of the movable roller, the curvature of the sling between adjacent fixed rollers is changed to adjust the length between the two ends of the sling.

[0023] Preferably, the driving device comprises a hydraulic cylinder, a piston rod of the hydraulic cylinder is provided with a connecting plate, and the connecting plate is connected to one end of the transmission member.

[0024] Preferably, a clamping block guide groove is provided on one side of the sling through hole, a movable clamping block is slidably connected in the guide groove, and a spring is provided between the movable clamping block and the bottom of the clamping block guide groove; a fixed clamping block is provided on the other side of the sling through hole; the sling passes between the movable clamping block and the fixed clamping block; the sling is clamped between the movable clamping block and the fixed clamping block.

[0025] The invention discloses a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam, which is constructed by a construction method of a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam.

[0026] The beneficial effects of the present invention are:

[0027] 1. The present invention adopts the prefabricated bottom concrete plate steel cofferdam construction technology, which reduces the amount of bottom concrete used and effectively shortens the construction period. Under the premise of ensuring the quality of the project, it reduces the risks of pouring large-area bottom concrete in terms of quality, safety and environmental protection, making the cofferdam bottom seal safe and reliable, while greatly improving the construction efficiency.

[0028] 2. The present invention adopts a whole circle of box-type segments to prefabricate double-wall steel cofferdams, uses digital software to accurately produce various components, and realizes batch full prefabrication and assembly. While ensuring the quality of prefabricated components, it greatly improves the construction and installation efficiency, reduces on-site construction steps, and shortens the construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the combination of prefabricated double-wall steel cofferdam and prefabricated bottom sealing concrete bottom plate;

[0030] Figure 2 It is a three-dimensional schematic diagram of the prefabricated double-walled steel cofferdam;

[0031] Figure 3 This is a top view of the prefabricated double-walled steel cofferdam;

[0032] Figure 4 This is a cross-sectional view of a prefabricated double-walled steel cofferdam;

[0033] Figure 5 This is a schematic diagram of the internal connection of two adjacent prefabricated double-walled steel cofferdams;

[0034] Figure 6 It is a top view of the precast bottom concrete slab;

[0035] Figure 7 It is a schematic diagram of the lifting system;

[0036] Figure 8 The construction process flow chart of the present invention;

[0037] Fig. 9 This is the flow chart of the automatic monitoring system.

[0038] Fig.10 This is a schematic diagram of hoisting the prefabricated double-wall steel cofferdam using slings.

[0039] Fig.11 It is a structural schematic diagram of the level adjustment member.

[0040] Fig.12 for Fig.11 Enlarged view of part A in the middle.

[0041] Fig.13 for Fig.11 Enlarged view of part B in the middle.

[0042] Fig.14 It is a schematic diagram of the transmission member in the level adjustment member when it moves.

[0043] In the figure: 1. Prefabricated double-wall steel cofferdam, 2. Prefabricated bottom concrete slab, 3. Outer plate, 4. Inner plate, 5. Square steel pipe, 6. Vertical ribs, 7. Connecting rods, 8. Gaskets, 9. Anchors, 10. Finished rolled threaded steel, 11. Guide rails, 12. Limit blocks, 13. Rotating shafts, 14. Positioning rods, 15. Corbels, 16. Purlins, 17. Diagonal braces, 18. Guide and positioning wheels, 19. Lifting rings, 20. Shoulder beams, 21. Steel casings, 22. Support plates, 23. Lifting jacks Top, 24, extended fine-rolled threaded steel, 25, sling, 26, level adjustment part, 26-1, adjustment part body, 26-2, sling through hole, 26-3, fixed roller, 26-4, movable roller, 26-5, transmission part, 26-6, inclined groove, 26-7, driving device, 26-8, slider, 26-9, clamping block guide groove, 26-10, movable clamping block, 26-11, spring, 26-12, fixed clamping block, 26-13, connecting plate. DETAILED DESCRIPTION

[0044] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0045] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0046] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0047] like Figures 1 to 14 As shown, a construction method of a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam comprises the following steps:

[0048] S1: Produce and assemble the prefabricated double-wall steel cofferdam 1; and transport the double-wall steel cofferdam to the construction site.

[0049] The structure of the prefabricated double-wall steel cofferdam 1 includes an outer plate 3 and an inner plate 4. Both the outer plate 3 and the inner plate 4 are provided with vertical ribs 6. A connecting rod 7 is provided between the outer plate 3 and the inner plate 4. One end of the connecting rod 7 is welded and fixed to the outer plate 3, and the other end of the connecting rod 7 is welded and fixed to the inner plate 4. A reserved hole is provided on the connecting rod 7. A positioning rod 14 and a guide rail 11 are provided on the inner side of the inner plate 4. The positioning rod 14 is arranged at the lower position of the inner plate 4, and the guide rail 11 corresponds to the positioning rod 14 one by one.

[0050] The guide rail 11 is rotatably connected to the inner plate 4; a rotating shaft 13 is provided on the inner plate 4, and one end of the guide rail 11 is rotatably connected to the rotating shaft 13 so that the guide rail 11 can rotate around the rotating shaft 13. A guide groove is provided on the guide rail 11, one end of which is open, and the positioning rod 14 can be inserted into the guide groove through the opening. A limit block 12 is provided on the open side of the guide rail 11.

[0051] A square steel pipe 5 is welded on the inner plate 4 of the double-wall steel cofferdam, and the square steel pipe 5 is welded to the upper and lower sides of the inner plate 4; the square steel pipe 5 located on the upper side is higher than the upper end of the inner plate 4 to form a bulge at the upper end of the inner plate 4, and the square steel pipe 5 located on the lower side is higher than the lower end of the inner plate 4 to form an embedded area between the square steel pipe 5 on the lower side and the lower side of the inner plate 4.

[0052] During the production process, BIM software is used to design the precise dimensions of various components required for the prefabricated double-wall steel cofferdam 1, realize the visual assembly of various components, establish a modular model, and directly generate design drawings, thereby realizing the standardized production of components.

[0053] S2: Install a lifting system on the steel casing 21, lift the steel bottom plate to the installation position, connect the lifting system to the steel bottom plate and adjust the steel bottom plate to a first height position, and splice adjacent steel bottom plates to obtain a prefabricated bottom-sealed concrete bottom plate 2.

[0054] The prefabricated bottom-sealed concrete floor 2 is formed by welding a plurality of steel floor plates. Before the steel floor plates are spliced ​​together, the steel floor plates are independently moved up and down by the lifting system; when the steel floor plates are spliced ​​together into a whole, the lifting system can drive the prefabricated bottom-sealed concrete floor 2 to move as a whole.

[0055] When installing the lifting system on the steel casing 21, the method is as follows:

[0056] A support plate 22 is installed on the top of the steel casing 21, and a jack 23 is installed on the support plate 22. The jack 23 is provided with an elongated finely rolled threaded steel bar 24, and the elongated finely rolled threaded steel bar 24 is connected to the steel bottom plate.

[0057] Furthermore, the steel bottom plate is provided with a guide positioning wheel 18, the steel bottom plate is provided with a shoulder pole beam 20, and the shoulder pole beam 20 is provided with a lifting ring 19; when the height of the bottom steel bottom plate is adjusted by the lifting system, the guide positioning wheel 18 contacts the outer wall of the steel casing 21.

[0058] The guide positioning wheel 18 is rotatably connected to the steel bottom plate; the guide positioning wheel 18 enables rolling contact between the steel bottom plate and the steel casing 21, thereby reducing the friction resistance between the steel bottom plate and the steel casing 21 when the steel bottom plate moves up and down.

[0059] S3: hoist the first prefabricated double-walled steel cofferdam 1 onto the prefabricated bottom concrete slab 2 and connect and fix it to the prefabricated bottom concrete slab 2; lay a waterstop above the prefabricated double-walled steel cofferdam 1; hoist the purlin 16 to the inner side of the prefabricated double-walled steel cofferdam 1 and fix it to the corbel 15 on the inner plate 4 of the prefabricated double-walled steel cofferdam 1.

[0060] In this step, the prefabricated double-walled steel cofferdam 1 and the prefabricated bottom concrete slab 2 are fixed by welding. The purlin 16 reinforces the prefabricated double-walled steel cofferdam 1. The purlin 16 is a rectangular frame structure, and the shape of the purlin 16 matches the shape of the inner plate 4. A diagonal brace 17 is provided at the corner of the purlin 16. The purlin 16 is welded and fixed to the corbel 15, and the purlin 16 is welded and fixed to the inner plate 4 at the same time.

[0061] In this embodiment, the corbel 15, the purlin 16 and the diagonal brace 17 are all made of I-shaped steel.

[0062] S4: hoist the second prefabricated double-walled steel cofferdam 1 to a set height above the first prefabricated double-walled steel cofferdam 1 and stop, adjust the angle of the current prefabricated double-walled steel cofferdam 1 so that the positioning rod 14 on the current prefabricated double-walled steel cofferdam 1 is aligned with the guide rail 11 on the lower prefabricated double-walled steel cofferdam 1, rotate the guide rail 11 on the lower prefabricated double-walled steel cofferdam 1 so that the positioning rod 14 on the current prefabricated double-walled steel cofferdam 1 extends into the guide groove on the guide rail 11; then continue to lower the current prefabricated double-walled steel cofferdam 1 and dock it with the prefabricated double-walled steel cofferdam 1 below; lay a waterstop above the current prefabricated double-walled steel cofferdam 1; hoist the purlin 16 to the inner side of the current prefabricated double-walled steel cofferdam 1 and fix it to the corbel 15 on the inner plate 4 of the prefabricated double-walled steel cofferdam 1.

[0063] In this step, the protrusion on the current double-walled steel cofferdam is embedded in the embedding area on the upper double-walled steel cofferdam.

[0064] During the process of hoisting and lowering the prefabricated double-walled steel cofferdam 1, the cooperation between the guide rail 11 and the positioning rod 14 plays a guiding role in the lowering of the prefabricated double-walled steel cofferdam 1, helping the upper prefabricated double-walled steel cofferdam 1 to accurately dock with the lower prefabricated double-walled steel cofferdam 1. The width of the guide groove is consistent with the diameter of the positioning rod 14. During the lowering process of the prefabricated double-walled steel cofferdam 1, the positioning rod 14 moves along the guide groove on the guide rail 11. After the upper and lower prefabricated double-walled steel cofferdams 1 are docked, they are fixed by welding. In this embodiment, the height distance is set to 20cm-25cm.

[0065] Monitor the hoisting process of the current prefabricated double-walled steel cofferdam 1 and record the position deviation data. When the position deviation data is greater than the design requirements, adjust the current prefabricated double-walled steel cofferdam 1. Specifically, use automated monitoring equipment to measure the top elevation of the prefabricated double-walled steel cofferdam 1, and use a total station to record the angle of the prefabricated double-walled steel cofferdam 1 during the hoisting process, the distance from the prefabricated double-walled steel cofferdam 1 below, and the three-dimensional coordinate data, and calculate the error. If the error meets the design requirements, continue to hoist and dock; if the error exceeds the set range, adjust the prefabricated double-walled steel cofferdam 1 until the error meets the requirements and continue to hoist and dock.

[0066] Furthermore, when the prefabricated double-walled steel cofferdam 1 is hoisted, one end of the sling 25 is connected to the prefabricated double-walled steel cofferdam 1, and the other end of the sling 25 is connected to the lifting equipment; a level adjustment part 26 is provided on the sling 25; an inclinometer is installed on the prefabricated double-walled steel cofferdam 1; the levelness of the prefabricated double-walled steel cofferdam 1 is monitored by the inclinometer; when the levelness of the prefabricated double-walled steel cofferdam 1 exceeds a preset range, the levelness of the prefabricated double-walled steel cofferdam 1 is adjusted by the level adjustment part 26.

[0067] The level adjustment member 26 includes an adjustment member body 26-1, a sling hole 26-2 is provided on the adjustment member body 26-1, a fixed roller 26-3 is provided on one side of the sling hole 26-2, a movable roller 26-4 is provided on the other side of the sling hole 26-2, and the sling 25 passes between the fixed roller 26-3 and the movable roller 26-4; the fixed roller 26-3 and the movable roller 26-4 are arranged alternately;

[0068] A guide hole corresponding to the movable roller 26-4 is provided on one side of the sling through hole 26-2, a slider 26-8 is slidably connected in the guide hole, the movable roller 26-4 is connected to one end of the slider 26-8, and the other end of the slider 26-8 is an arc surface; a guide groove of a transmission member 26-5 is provided on the side of the guide hole away from the sling through hole 26-2, a transmission member 26-5 is slidably connected in the guide groove of the transmission member 26-5, and an inclined groove 26-6 corresponding to the slider 26-8 is provided on the transmission member 26-5;

[0069] The inclined surface groove 26-6 includes a groove bottom surface and inclined surfaces at both ends of the inclined surface groove 26-6, the lower end of the inclined surface is connected to the groove bottom surface, and the upper end of the inclined surface is connected to the outer plane of the transmission member 26-5; the length between the upper ends of the inclined surfaces at both ends of the inclined surface groove 26-6 is equal to the length of the groove bottom surface of the adjacent inclined surface groove 26-6 below;

[0070] A driving device 26-7 for driving the transmission member 26-5 to move is also provided on the adjusting member body 26-1; the driving device 26-7 drives the transmission member 26-5 to move along the inclined surface on the inclined surface groove 26-6 to drive the slider 26-8 and the movable roller 26-4 to move axially along the guide hole; by changing the position of the movable roller 26-4, the curvature of the sling 25 between adjacent fixed rollers 26-3 is changed to adjust the length between the two ends of the sling 25.

[0071] When the transmission member 26-5 is moving, the extension movement of each movable roller 26-4 has a certain order. When the transmission member 26-5 is at the initial position, each movable roller 26-4 just stays in the middle position of the corresponding inclined groove 26-6; when the transmission member 26-5 starts to move from the initial position, the movable roller 26-4 located at the top first contacts the inclined surface and starts to push outward, and after the movable roller 26-4 pushes out, it contacts the sling 25 and causes the sling 25 to bend; when the movable roller 26-4 moves to the high end of the inclined surface, the adjacent movable roller 26-4 below just moves to the low end of the inclined surface, and as the transmission member 26-5 moves, the movable roller 26-4 below will move along the inclined surface toward the high end. The movable roller 26-4 below is extended and contacts with the sling 25, thereby causing another position on the sling 25 to bend. In this way, when the transmission member 26-5 moves, each movable roller 26-4 can be extended in a certain order. As the bending amplitude increases or the full position points on the sling 25 increase, the length between the two ends of the sling 25 gradually decreases. On the contrary, when the transmission member 26-5 moves in the opposite direction to the initial position, the length between the two ends of the sling 25 gradually increases. By adjusting the length between the two ends of each sling 25, the horizontal degree of the prefabricated double-wall steel cofferdam 1 can be adjusted.

[0072] In this embodiment, the prefabricated double-walled steel cofferdam 1 is hoisted by four slings 25 at the same time. When the levelness of the prefabricated double-walled steel cofferdam 1 changes and exceeds the levelness requirement during hoisting, the distance between the two ends of the slings 25 is adjusted by the levelness adjusting member 26 to make the prefabricated double-walled steel cofferdam 1 return to a horizontal state, so as to ensure the accurate docking of the upper and lower prefabricated double-walled steel cofferdams 1.

[0073] The driving device 26-7 includes a hydraulic cylinder, a piston rod of which is provided with a connecting plate 26-13, and the connecting plate 26-13 is connected to one end of the transmission member 26-5. The transmission member 26-5 is driven to move by the hydraulic cylinder.

[0074] A clamping block guide groove 26-9 is provided on one side of the sling hole 26-2, and a movable clamping block 26-10 is slidably connected in the guide groove, and a spring 26-11 is provided between the movable clamping block 26-10 and the bottom of the clamping block guide groove 26-9; a fixed clamping block 26-12 is provided on the other side of the sling hole 26-2; the sling 25 passes between the movable clamping block 26-10 and the fixed clamping block 26-12; the sling 25 is clamped between the movable clamping block 26-10 and the fixed clamping block 26-12. Through the clamping of the sling 25 by the movable clamping block 26-10 and the fixed clamping block 26-12, the horizontal adjustment member can stably stay at a certain position on the sling 25.

[0075] S5: Install the fine-rolled threaded steel bar 10 between two vertically adjacent prefabricated double-walled steel cofferdams 1.

[0076] Among them, the two ends of the fine-rolled threaded steel bar 10 respectively pass through the reserved holes on the connecting rod 7 on the two vertically adjacent prefabricated double-wall steel cofferdams 1, and the two ends of the fine-rolled threaded steel bar 10 are respectively fastened to the connecting rod 7 through a gasket 8 and an anchor 9; when the fine-rolled threaded steel bar 10 is fastened, one end of the fine-rolled threaded steel bar 10 is connected to the jack 23, and a tensile force is applied to the fine-rolled threaded steel bar 10 through the jack 23 to tension the fine-rolled threaded steel bar 10.

[0077] S6: Adjust the prefabricated bottom sealing concrete bottom plate 2 to the second height position through the lifting system.

[0078] S7: Repeat steps S4 and S5 to complete the installation of the third prefabricated double-walled steel cofferdam 1; the prefabricated double-walled steel cofferdam 1 and the prefabricated bottom concrete slab 2 together form a steel hanging box; a temporary support is set below the prefabricated bottom concrete slab 2, water is injected into the steel hanging box and the steel hanging box is lowered to contact with the temporary support through a lifting system; when the steel hanging box contacts with the temporary support, the steel hanging box reaches the designed elevation position; underwater concrete construction operations are carried out below the steel hanging box.

[0079] S8: Pump out the water in the steel hanging box and dismantle the lifting system.

[0080] S9: After approval by the technical department, cast the foundation and complete the construction of the precast beam and slab bottom double-wall steel-concrete composite hanging box cofferdam.

[0081] A prefabricated beam-slab bottom-sealed double-walled steel-concrete composite hanging box cofferdam is constructed by the above-mentioned prefabricated beam-slab bottom-sealed double-walled steel-concrete composite hanging box cofferdam construction method.

[0082] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to those of the present application fall within the protection scope of the present invention.

Claims

1. A construction method for a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam, characterized in that: The following steps are involved: S1: Produce and assemble the prefabricated double-walled steel cofferdam (1); and transport the prefabricated double-walled steel cofferdam to the construction site; S2: installing a lifting system on the steel casing (21), lifting the steel bottom plate to the installation position, connecting the lifting system to the steel bottom plate and adjusting the steel bottom plate to a first height position, and splicing adjacent steel bottom plates to obtain a prefabricated bottom-sealed concrete bottom plate (2); S3: hoisting the first prefabricated double-walled steel cofferdam (1) onto the prefabricated bottom concrete slab (2) and connecting and fixing it to the prefabricated bottom concrete slab (2); laying a water stop strip on the prefabricated double-walled steel cofferdam (1); hoisting the purlin (16) to the inner side of the prefabricated double-walled steel cofferdam (1) and fixing it to the corbel (15) on the inner plate (4) of the prefabricated double-walled steel cofferdam (1); S4: When the second prefabricated double-walled steel cofferdam (1) is hoisted to a set height above the first prefabricated double-walled steel cofferdam (1), the second prefabricated double-walled steel cofferdam (1) is stopped, the angle of the current prefabricated double-walled steel cofferdam (1) is adjusted so that the positioning rod (14) on the current prefabricated double-walled steel cofferdam (1) is aligned with the guide rail (11) on the lower prefabricated double-walled steel cofferdam (1), and the guide rail (11) on the lower prefabricated double-walled steel cofferdam (1) is rotated so that the positioning rod (14) on the current prefabricated double-walled steel cofferdam (1) is inserted into the guide groove on the guide rail (11); then the current prefabricated double-walled steel cofferdam (1) is lowered and docked with the lower prefabricated double-walled steel cofferdam (1); a water stop is laid above the current prefabricated double-walled steel cofferdam (1); a purlin (16) is hoisted to the inner side of the current prefabricated double-walled steel cofferdam (1) and fixed to the bracket (15) on the inner plate (4) of the prefabricated double-walled steel cofferdam (1); S5: installing a finely rolled threaded steel bar (10) between two vertically adjacent prefabricated double-walled steel cofferdams (1); S6: adjusting the prefabricated bottom sealing concrete bottom plate (2) to a second height position through the lifting system; S7: Repeat steps S4 and S5 to complete the installation of the third prefabricated double-walled steel cofferdam (1); the prefabricated double-walled steel cofferdam (1) and the prefabricated bottom-sealing concrete slab (2) together form a steel hanging box; a temporary support is provided below the prefabricated bottom-sealing concrete slab (2), water is injected into the steel hanging box and the steel hanging box is lowered to contact the temporary support through the lifting system; underwater concrete construction operations are performed below the steel hanging box; S8: Pump out the water in the steel hanging box and dismantle the lifting system.

2. The construction method of a prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 1 is characterized in that: The prefabricated double-walled steel cofferdam (1) comprises an outer plate (3) and an inner plate (4), wherein a connecting rod (7) is provided between the outer plate (3) and the inner plate (4); a reserved hole is provided on the connecting rod (7); two ends of the fine-rolled threaded steel (10) respectively pass through the reserved holes on the connecting rods (7) on two vertically adjacent prefabricated double-walled steel cofferdams (1), and the two ends of the fine-rolled threaded steel (10) are respectively fastened to the connecting rods (7) via gaskets (8) and anchors (9); when the fine-rolled threaded steel (10) is fastened, one end of the fine-rolled threaded steel (10) is connected to a jack (23), and a tensile force is applied to the fine-rolled threaded steel (10) via the jack (23), thereby tensioning the fine-rolled threaded steel (10).

3. The construction method of a prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 1 is characterized in that: In step S (2), when installing the lifting system on the steel casing (21), the method is as follows: A support plate (22) is installed on the top of the steel casing (21), a jack (23) is installed on the support plate (22), and an extended finely rolled threaded steel bar (24) is provided on the jack (23), and the extended finely rolled threaded steel bar (24) is connected to the steel bottom plate.

4. The construction method of a prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 1 is characterized in that: A guide positioning wheel (18) is provided on the steel bottom plate, a shoulder pole beam (20) is provided on the steel bottom plate, and a lifting ring (19) is provided on the shoulder pole beam (20); when the height of the bottom steel bottom plate is adjusted by the lifting system, the guide positioning wheel (18) contacts the outer wall of the steel casing (21).

5. The construction method of a prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 1 is characterized in that: A square steel pipe (5) is welded to the inner plate (4) of the prefabricated double-walled steel cofferdam, and the square steel pipe (5) is welded to the upper and lower sides of the inner plate (4); the square steel pipe (5) located on the upper side is higher than the upper end of the inner plate (4) so ​​that a protrusion is formed at the upper end of the inner plate (4); the square steel pipe (5) located on the lower side is higher than the lower end of the inner plate (4) so ​​that an embedded area is formed between the square steel pipe (5) on the lower side and the lower end of the inner plate (4); the protrusion on the prefabricated double-walled steel cofferdam is embedded in the embedded area on the upper prefabricated double-walled steel cofferdam.

6. The construction method of a prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 1 is characterized in that: When the prefabricated double-walled steel cofferdam (1) is hoisted, one end of a sling (25) is connected to the prefabricated double-walled steel cofferdam (1), and the other end of the sling (25) is connected to a hoisting device; a level adjustment member (26) is provided on the sling (25); an inclinometer is installed on the prefabricated double-walled steel cofferdam (1); the level of the prefabricated double-walled steel cofferdam (1) is monitored by the inclinometer; when the level of the prefabricated double-walled steel cofferdam (1) exceeds a preset range, the level of the prefabricated double-walled steel cofferdam (1) is adjusted by the level adjustment member (26).

7. The construction method of a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 6 is characterized in that: The level adjustment member (26) comprises an adjustment member body (26-1), the adjustment member body (26-1) is provided with a sling through hole (26-2), a fixed roller (26-3) is provided on one side of the sling through hole (26-2), a movable roller (26-4) is provided on the other side of the sling through hole (26-2), the sling (25) passes between the fixed roller (26-3) and the movable roller (26-4); the fixed roller (26-3) and the movable roller (26-4) are arranged alternately; A guide hole corresponding to the movable roller (26-4) is provided on one side of the sling through hole (26-2), a slider (26-8) is slidably connected in the guide hole, the movable roller (26-4) is connected to one end of the slider (26-8), and the other end of the slider (26-8) is an arc surface; a transmission member (26-5) guide groove is provided on the side of the guide hole away from the sling through hole (26-2), a transmission member (26-5) is slidably connected in the transmission member (26-5) guide groove, and an inclined groove (26-6) corresponding to the slider (26-8) is provided on the transmission member (26-5); The inclined surface groove (26-6) comprises a groove bottom surface and inclined surfaces at both ends of the inclined surface groove (26-6), the lower end of the inclined surface is connected to the groove bottom surface, and the upper end of the inclined surface is connected to the outer surface of the transmission member (26-5); the length between the upper ends of the inclined surfaces at both ends of the inclined surface groove (26-6) is equal to the length of the groove bottom surface on the adjacent inclined surface groove (26-6) below; The adjusting member body (26-1) is also provided with a driving device (26-7) for driving the transmission member (26-5) to move; the driving device (26-7) drives the transmission member (26-5) to move along the inclined surface on the inclined surface groove (26-6) to drive the slider (26-8) and the movable roller (26-4) to move along the axial direction of the guide hole; and by changing the position of the movable roller (26-4), the curvature of the sling (25) between adjacent fixed rollers (26-3) is changed to adjust the length between the two ends of the sling (25).

8. The construction method of a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 7 is characterized in that: The driving device (26-7) comprises a hydraulic cylinder, a piston rod of which is provided with a connecting plate (26-13), and the connecting plate (26-13) is connected to one end of the transmission member (26-5).

9. The construction method of a prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam according to claim 7, characterized in that: A clamping block guide groove (26-9) is provided on one side of the sling through hole (26-2), a movable clamping block (26-10) is slidably connected in the clamping block guide groove (26-9), and a spring (26-11) is provided between the movable clamping block (26-10) and the bottom of the clamping block guide groove (26-9); a fixed clamping block (26-12) is provided on the other side of the sling through hole (26-2); the sling (25) passes between the movable clamping block (26-10) and the fixed clamping block (26-12); the sling (25) is clamped between the movable clamping block (26-10) and the fixed clamping block (26-12).

10. A prefabricated beam and slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam, characterized in that: The cofferdam is obtained by the construction method of the prefabricated beam-slab bottom-sealed double-wall steel-concrete composite hanging box cofferdam described in any one of claims 1-9.

Images