Steel sheet pile and double-wall steel hanging box combined cofferdam and construction method

Abstract

The invention belongs to the technical field of bridge foundation construction fences and pier collision prevention, and particularly relates to a steel sheet pile and double-wall steel hanging box combined cofferdam and a construction method. A steel sheet pile and double-wall steel hanging box combined cofferdam comprises a double-wall steel boxed cofferdam, a steel sheet pile cofferdam and a pile foundation, the double-wall steel boxed cofferdam is installed above the pile foundation and comprises a steel boxed cofferdam bottom plate, a steel boxed cofferdam wall plate and a wall plate top reinforcing truss, bottom sealing concrete is arranged on the upper portion of the steel boxed cofferdam bottom plate, and the steel boxed cofferdam bottom plate is arranged on the steel boxed cofferdam wall plate. The steel sheet pile cofferdam comprises a Larsen type steel sheet pile, an outer waling, an inner waling and a waling bracket, a connecting device is arranged on the lower portion of the Larsen type steel sheet pile, and the Larsen type steel sheet pile is connected with the upper portion of the steel jacket box cofferdam wall plate through the connecting device. The steel sheet pile cofferdam and the double-wall steel jacket box cofferdam are connected through the connecting device, the steel sheet pile cofferdam serves as a water retaining structure and can be recycled and reused, the one-time steel investment of the double-wall steel cofferdam is reduced, and the construction cost of the cofferdam is greatly reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge foundation construction enclosures and bridge pier anti-collision, and in particular relates to a steel sheet pile and double-wall steel hanging box combined cofferdam and a construction method. Background Art

[0002] High pile cap is a common structural form in the design of bridge pile foundation, and its main construction method is to use steel box cofferdam. There is often a need for ships to pass through at the bridge location, and the construction of the bridge will affect the passage of passing ships. At present, there are many cases of ships colliding with bridges in China, which not only poses a great safety hazard to the normal operation of the bridge, but also has a great impact on shipping. In order to ensure the safety of the bridge and prevent ships from colliding with the bridge and causing destructive damage, anti-collision facilities will be set up on the pier cap to absorb most of the impact energy and the destructive force of the ship collision. The existing anti-collision measures will use the double-walled steel cofferdam during construction as an anti-collision structure, which has high rigidity, light weight, good toughness and good deformation ability. However, as an anti-collision structure, it mainly protects the cap. During the construction period, it is affected by the construction water level, and there will be a situation where the top elevation of the cofferdam is higher than the top of the cap. If the double-wall structure is used throughout the height range of the cofferdam, there will be problems such as large steel consumption and cutting off the super-high part in the later stage. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide a combined cofferdam of steel sheet piles and double-walled steel hanging boxes and a construction method. The combined cofferdam is connected to the steel sheet pile cofferdam and the double-walled steel box cofferdam by setting a connecting device to form a combined cofferdam. The steel sheet pile cofferdam is used in the upper part only as a water retaining structure; the double-walled steel box cofferdam is used in the lower part as a water retaining structure and anti-collision facility. The steel sheet pile cofferdam can be recycled and reused, reducing the one-time steel investment in the double-walled steel cofferdam. Under the conditions of meeting the water retaining function of the cofferdam, force requirements, and safe construction, the construction cost of the cofferdam is greatly reduced.

[0004] The technical solution of the present invention is: a steel sheet pile and double-wall steel hanging box combined cofferdam, including a double-wall steel box cofferdam, a steel sheet pile cofferdam and a pile foundation, the double-wall steel box cofferdam is installed above the pile foundation, including a steel box cofferdam bottom plate, a steel box cofferdam wall plate and a reinforcing truss on the top of the wall plate, the upper part of the steel box cofferdam bottom plate is provided with bottom sealing concrete, the steel sheet pile cofferdam includes Larsen type steel sheet piles, an outer wall, an inner wall, and a wall corbel, the lower part of the Larsen type steel sheet pile is provided with a connecting device, and the Larsen type steel sheet pile is connected to the upper part of the steel box cofferdam wall plate through the connecting device.

[0005] The surrounding corbels are located below the inner surroundings, and a plurality of inner supports are connected between the inner surroundings.

[0006] A plurality of columns are fixedly arranged in the bottom sealing concrete, the columns are vertically arranged, and the upper parts thereof extend into the interior of the steel sheet pile cofferdam, and the inner support is connected to the columns.

[0007] The connecting device includes two limit trusses, anchoring channels and tension bolts. Two steel panels are arranged at the lower part of the two limit trusses 5 within the height range of the limit trusses. The steel panels are fixed to the inner wall of the top of the steel casing cofferdam wall panel. The steel panels are filled with water-expanding water-stopping mortar. The Larsen steel sheet piles are embedded between the limit trusses. Anchoring channels are respectively arranged on the opposite sides of the limit trusses. The anchoring channels are welded to the limit trusses. The anchoring channels adopt a lattice section and a double-limb arrangement. Tension bolt holes are reserved between the two limbs. The anchoring channels are fixedly connected with tension bolts.

[0008] The tension bolts are provided with water stop nuts at one end near the outer side of the cofferdam between the anchor channels, the holes between the water stop nuts and the Larsen steel sheet piles are filled with welds, and the tension bolts are provided with square wood pads at the connection between the anchor channels.

[0009] An end plate is arranged between the bottom of the Larsen steel sheet pile and the anchor channel steel.

[0010] A construction method for a steel sheet pile and double-wall steel hanging box combined cofferdam, the construction of the steel sheet pile and double-wall steel hanging box combined cofferdam as described above, comprising the following steps: S1: Process the double-walled steel box cofferdam according to the design drawing and process the connecting device at the same time; S2: After the pile foundation construction is completed, the steel trestle at the cap will be dismantled, and a suspension lowering device and a double-walled steel cofferdam assembly platform will be set up. The double-walled steel box cofferdam will be assembled in sequence on site using lifting equipment; S3: After the double-walled steel box cofferdam is assembled, non-destructive testing is performed on the assembly welds of the double-walled steel box cofferdam, and a temporary lowering boom is installed to lower the double-walled steel box cofferdam; S4: After the lower double-walled steel box cofferdam is lowered to the preset elevation, the steel sheet pile cofferdam is installed through the connecting device. The installation should be avoided in windy weather; S5: After the steel sheet pile cofferdam is installed, continue to lower the double-wall steel box cofferdam to the designed elevation, install the temporary hanger, dismantle the suspension lowering equipment and components, pour the bottom concrete, and pump water from the weir after the concrete strength reaches the design requirements. After pumping water to the designed position of the inner support, install the inner support in time; S6: After the pumping is completed, the temporary lowering boom is removed, and the pile head treatment, pile foundation inspection and foundation construction are carried out to complete the construction of the steel sheet pile and double-wall steel hanging box combined cofferdam.

[0011] After the construction of the combined cofferdam of steel sheet piles and double-walled steel hanging boxes is completed in step S6, the construction of the inner pedestal and pier body of the cofferdam is continued. After the construction of the inner pedestal and pier body of the combined cofferdam is completed, the diver dives to the connection device to release the connection and dismantle the steel sheet pile cofferdam.

[0012] The technical effects of the present invention are as follows: 1. The present invention connects the steel sheet pile cofferdam with the double-walled steel casing cofferdam by setting a connecting device to form a combined cofferdam, wherein the steel sheet pile cofferdam is used at the upper part only as a water retaining structure; the double-walled steel casing cofferdam is used at the lower part as a water retaining structure and an anti-collision facility, and the steel sheet pile cofferdam can be recycled and reused, thereby reducing the one-time steel input of the double-walled steel cofferdam, and greatly reducing the construction cost of the cofferdam under the conditions of meeting the water retaining function, force requirements, and safe construction of the cofferdam; 2. The present invention connects the steel sheet pile cofferdam with the double-walled steel casing cofferdam by a connecting device, and can realize rapid assembly and rapid disassembly on site, thereby accelerating the construction speed of the cofferdam and ensuring the construction progress; 3. The structural form of the combined cofferdam of the double-walled steel casing and the steel sheet pile of the present invention is more in line with the force characteristics of the cofferdam, and the water pressure is distributed in a triangular shape. The double-walled steel casing section is designed at the bottom of the cofferdam to resist the strong water pressure, and the steel sheet pile is designed at the top of the cofferdam to meet the force requirements and reduce the deadweight of the entire structure.

[0013] The following is a further description with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural elevation view of a cofferdam composed of steel sheet piles and double-walled steel hanging boxes according to an embodiment of the present invention.

[0015] Figure 2 This is a structural plan view of a cofferdam composed of steel sheet piles and double-walled steel hanging boxes according to an embodiment of the present invention.

[0016] Figure 3 This is a plan view of a steel sheet pile cofferdam according to an embodiment of the present invention.

[0017] Figure 4 This is a plan view of the connection between the double-walled steel box cofferdam and the steel sheet pile cofferdam according to an embodiment of the present invention.

[0018] Figure 5 This is a plan view of a connecting device according to an embodiment of the present invention.

[0019] Figure numbers: 1-double-walled steel box cofferdam, 101-steel box cofferdam bottom plate, 102-steel box cofferdam wall plate, 103-wall plate top reinforcement truss, 104-bottom sealing concrete, 2-inner support, 3-column, 4-steel sheet pile cofferdam, 401-Larsen steel sheet pile, 402-outer cofferdam, 403-inner cofferdam, 404-cofferdam corbel, 5-connecting device, 501-limiting truss, 502-anchor channel steel, 503-tension bolts, 504-square timber support pads, 505-waterstop nuts, 506-end plates, 6-pile foundation. DETAILED DESCRIPTION Example 1

[0020] like Figure 1~Figure 5 As shown, a steel sheet pile and double-wall steel hanging box combined cofferdam includes a double-wall steel box cofferdam 1, a steel sheet pile cofferdam 4 and a pile foundation 6. The double-wall steel box cofferdam 1 is installed above the pile foundation 6, including a steel box cofferdam bottom plate 101, a steel box cofferdam wall plate 102 and a reinforcing truss 103 on the top of the wall plate. The upper part of the steel box cofferdam bottom plate 101 is provided with a bottom sealing concrete 104. The steel sheet pile cofferdam 4 includes a Larsen type steel sheet pile 401, an outer wall 402, an inner wall 403, and a wall corbel 404. The lower part of the Larsen type steel sheet pile 401 is provided with a connecting device 5, and the Larsen type steel sheet pile 401 is connected to the upper part of the steel box cofferdam wall plate 102 through the connecting device 5.

[0021] During actual use, the present invention connects the steel sheet pile cofferdam with the double-walled steel box cofferdam by arranging a connecting device to form a combined cofferdam. The steel sheet pile cofferdam is used in the upper part only as a water retaining structure; the double-walled steel box cofferdam is used in the lower part as a water retaining structure and an anti-collision facility. The steel sheet pile cofferdam can be recycled and reused, reducing the one-time steel investment in the double-walled steel cofferdam. Under the conditions of meeting the water retaining function of the cofferdam, force requirements, and safe construction, the construction cost of the cofferdam is greatly reduced. Example 2

[0022] Preferably, on the basis of Example 1, in this embodiment, the surrounding corbel 404 is located below the inner surrounding corbel 403 , and a plurality of inner supports 2 are connected between the inner surrounding corbels 403 .

[0023] During actual use, the cofferdam corbel 404 of the present invention is located below the inner cofferdam 403, and a plurality of inner supports 2 are connected between the inner cofferdams 403, and the inner supports 2 ensure that the steel sheet pile cofferdam 4 has sufficient structural strength. Example 3

[0024] Preferably, on the basis of Example 1 or Example 2, in this embodiment, a plurality of columns 3 are fixedly provided in the bottom sealing concrete 104 , the columns 3 are vertically arranged, and the upper parts thereof extend into the interior of the steel sheet pile cofferdam 4 , and the inner support 2 is connected to the columns 3 .

[0025] During actual use, a plurality of columns 3 are fixedly provided in the bottom sealing concrete 104 of the present invention. The columns 3 are vertically arranged, and the upper parts thereof extend into the interior of the steel sheet pile cofferdam 4. The inner support 2 is connected to the columns 3. The connection between the inner support 2 and the columns 3 ensures the structural stability of the inner support 2. Example 4

[0026] Preferably, on the basis of Example 1, in this embodiment, the connecting device 5 includes two limiting trusses 501, anchoring channels 502 and tension bolts 503, two steel panels are arranged at the lower part of the two limiting trusses 501 within the height range of the limiting trusses, the steel panels are fixed to the inner wall of the top of the steel casing cofferdam wall panel 102, the steel panels are filled with water-swelling waterproofing mortar, the Larsen-type steel sheet piles 401 are embedded between the limiting trusses 501, and anchoring channels 502 are respectively arranged on opposite sides of the limiting trusses 501, the anchoring channels 502 are welded to the limiting trusses 501, the anchoring channels 502 adopt a lattice section, a double-limb arrangement, tension bolt holes are reserved between the two limbs, and the anchoring channels 502 are fixedly connected by tension bolts 503.

[0027] During actual use, the present invention connects the steel sheet piles with the double-walled steel casing cofferdam through a connecting device, the connecting device 5 includes two limiting trusses 501, anchoring channels 502 and tension bolts 503, two steel panels are arranged at the lower part of the two limiting trusses 501 within the height range of the limiting trusses, the steel panels are fixed to the inner wall of the top of the steel casing cofferdam wall plate 102, the steel panels are filled with water-expanding waterproofing mortar, the Larsen type steel sheet piles 401 are embedded between the limiting trusses 501, the limiting trusses 501 are respectively provided with anchoring channels 502 on opposite sides, the anchoring channels 502 are welded to the limiting trusses 501, the anchoring channels 502 adopt a lattice section, a double-limb arrangement, and a tension bolt hole is reserved between the two limbs, the anchoring channels 502 are fixedly connected by tension bolts 503, and can be quickly assembled and disassembled on site, thereby accelerating the construction speed of the cofferdam and ensuring the construction progress. Example 5

[0028] Preferably, on the basis of Example 1 or Example 4, in this embodiment, the tension bolt 503 is provided with a water stop nut 505 at one end near the outer side of the cofferdam between the anchor channel steels 502, the hole gap between the water stop nut 505 and the Larsen steel sheet pile 401 is filled by a weld, and the tension bolt 503 is provided with a square wood support pad 504 at the connection between the anchor channel steels 502.

[0029] During actual use, the tension bolt 503 of the present invention is provided with a water stop nut 505 at one end near the outer side of the cofferdam between the anchor channel steel 502, and the hole gap between the water stop nut 505 and the Larsen steel sheet pile 401 is filled with a weld to prevent water leakage. The tension bolt 503 is provided with a square wood support pad 504 at the connection position to ensure the rigidity of the anchor channel steel 502, and the steel sheet pile 401 is tightly supported and padded with the anchor channel steel 502 to prevent the steel sheet pile 401 from slipping. Example 6

[0030] Preferably, on the basis of Example 1 or Example 5, in this embodiment, an end plate 506 is provided between the bottom of the Larsen steel sheet pile 401 and the anchor channel steel 502 .

[0031] During actual use, an end plate 506 is provided between the bottom of the Larsen steel sheet pile 401 and the anchor channel steel 502 to increase the self-sustaining property of the steel sheet pile 401 and prevent the steel sheet pile 401 from tipping over laterally during assembly. Example 7

[0032] A construction method for a steel sheet pile and double-wall steel hanging box combined cofferdam, the construction of the steel sheet pile and double-wall steel hanging box combined cofferdam as described above, comprising the following steps: S1: Process the double-walled steel box cofferdam 1 according to the design drawing, and process the connecting device 5 at the same time; S2: After the construction of pile foundation 6 is completed, the steel trestle at the abutment is dismantled, and a suspension lowering device and a double-walled steel cofferdam assembly platform are set up. The double-walled steel box cofferdam 1 is assembled in sequence on site using lifting equipment; S3: After the double-walled steel box cofferdam 1 is assembled, the assembly welds of the double-walled steel box cofferdam 1 are subjected to non-destructive testing, and a temporary lowering boom is installed to lower the double-walled steel box cofferdam 1. At the same time, the positioning truss and anchoring channel steel on the top of the double-walled steel cofferdam are installed during the post-production period, saving on-site installation time and reducing the risk of suspended installation; S4: After the lower double-walled steel box cofferdam 1 is lowered to the preset elevation, the steel sheet pile cofferdam 4 is installed through the connecting device 5. The installation should be avoided in windy weather; S5: After the steel sheet pile cofferdam 4 is installed, the double-walled steel box cofferdam 1 is lowered to the designed elevation. After installing the temporary hanger, the suspension lowering equipment and components are removed, and the bottom sealing concrete 104 is poured. After the concrete strength reaches the design requirements, water is pumped out of the weir. After the water is pumped to the designed position of the inner support, the inner support 2 is installed in time. S6: After the pumping is completed, the temporary lowering boom is removed, and the pile head treatment, pile foundation inspection and foundation construction are carried out to complete the construction of the steel sheet pile and double-wall steel hanging box combined cofferdam.

[0033] After the construction of the combined cofferdam of steel sheet piles and double-walled steel hanging boxes is completed in step S6, the construction of the inner pedestal and pier body of the cofferdam is continued. After the construction of the inner pedestal and pier body of the combined cofferdam is completed, the diver dives to the connecting device 5 to release the connection and dismantle the steel sheet pile cofferdam 4.

[0034] The combined cofferdam of steel sheet piles and double-walled steel hanging boxes of the present invention is mainly used as a water retaining structure for the construction of the pedestal during the construction period, providing a space for the construction of the pedestal. Compared with the prior art, the entire casing cofferdam adopts a double-walled steel casing, which consumes a large amount of steel and is difficult to dismantle in the later stage. Therefore, the present invention connects the steel sheet piles with the double-walled steel hanging box by setting a connecting device to form a combined cofferdam, and adopts a steel sheet pile cofferdam in the upper part as only a water retaining structure; and adopts a double-walled steel casing cofferdam in the lower part as a water retaining structure and an anti-collision facility. After the later construction is completed, the steel sheet pile cofferdam is recycled and reused to reduce the input of steel for the cofferdam. This structural form is more in line with the force mode of the cofferdam, ensures the force safety with the most reasonable structural form, and at the same time reduces resource input, speeds up the construction progress, and has better applicability, economy and safety.

[0035] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A steel sheet pile and double-wall steel hanging box combined cofferdam, characterized in that: The invention comprises a double-walled steel box cofferdam (1), a steel sheet pile cofferdam (4) and a pile foundation (6). The double-walled steel box cofferdam (1) is installed above the pile foundation (6) and comprises a steel box cofferdam bottom plate (101), a steel box cofferdam wall plate (102) and a wall plate top reinforcement truss (103). The upper part of the steel box cofferdam bottom plate (101) is provided with a bottom sealing concrete (104). The steel sheet pile cofferdam (4) comprises a Larsen type steel sheet pile (401), an outer wall (402), an inner wall (403) and a wall corbel (404). The lower part of the Larsen type steel sheet pile (401) is provided with a connecting device (5). The Larsen type steel sheet pile (401) is connected to the upper part of the steel box cofferdam wall plate (102) through the connecting device (5).

2. According to claim 1, a steel sheet pile and double-walled steel hanging box combined cofferdam is characterized by: The surrounding corbels (404) are located below the inner surroundings (403), and a plurality of inner supports (2) are connected between the inner surroundings (403).

3. According to claim 2, a steel sheet pile and double-walled steel hanging box combined cofferdam is characterized by: A plurality of columns (3) are fixedly arranged in the bottom sealing concrete (104); the columns (3) are arranged vertically, and the upper parts thereof extend into the interior of the steel sheet pile cofferdam (4); and the inner support (2) is connected to the columns (3).

4. According to claim 1, a steel sheet pile and double-walled steel hanging box combined cofferdam is characterized by: The connection device (5) comprises two limiting trusses (501), anchoring channel steels (502) and tension bolts (503). Two steel panels are arranged at the lower part of the two limiting trusses (501) within the height range of the limiting trusses. The steel panels are fixed to the inner side wall of the top of the steel casing cofferdam wall plate (102). Water-swelling waterproofing mortar is filled between the steel panels. The Larsen steel sheet piles (401) are embedded between the limiting trusses (501). Anchoring channel steels (502) are respectively arranged on opposite sides of the limiting trusses (501). The anchoring channel steels (502) are welded to the limiting trusses (501). The anchoring channel steels (502) adopt a lattice cross-section and a double-limb arrangement. Tension bolt holes are reserved between the two limbs. The anchoring channel steels (502) are fixedly connected by tension bolts (503).

5. According to claim 1, a steel sheet pile and double-walled steel hanging box combined cofferdam is characterized by: The tension bolts (503) are provided with water stop nuts (505) at one end close to the outer side of the cofferdam between the anchoring channel steels (502); a hole gap between the water stop nuts (505) and the Larsen steel sheet piles (401) is filled by a weld; and a square wood support pad (504) is provided at the connection between the tension bolts (503) and the anchoring channel steels (502).

6. The steel sheet pile and double-walled steel hanging box combined cofferdam according to claim 4 is characterized by: An end plate (506) is provided between the bottom of the Larsen steel sheet pile (401) and the anchor channel steel (502).

7. A construction method of a steel sheet pile and double-walled steel hanging box combined cofferdam, constructing a steel sheet pile and double-walled steel hanging box combined cofferdam as claimed in claim 1, characterized in that: The following steps are involved: S1: Processing the double-walled steel box cofferdam (1) according to the design drawing and processing the connecting device (5); S2: After the pile foundation (6) is constructed, the steel trestle at the abutment is dismantled, a suspension lowering device and a double-walled steel cofferdam assembly platform are set up, and the double-walled steel box cofferdam (1) is assembled in sequence on site using a lifting device; S3: After the double-walled steel box cofferdam (1) is assembled, a non-destructive flaw detection is performed on the assembly welds of the double-walled steel box cofferdam (1), a temporary lowering boom is installed, and the double-walled steel box cofferdam (1) is lowered; S4: After the lower double-walled steel box cofferdam (1) is lowered to the preset elevation, the steel sheet pile cofferdam (4) is installed through the connecting device (5). The installation should be avoided in windy weather; S5: After the steel sheet pile cofferdam (4) is installed, the double-walled steel box cofferdam (1) is lowered to the designed elevation, and after installing the temporary suspension rod, the suspension lowering equipment and components are removed, and the bottom sealing concrete (104) is poured. After the concrete strength reaches the design requirement, water is pumped out of the cofferdam, and after the water is pumped to the designed position of the inner support, the inner support (2) is installed in time; S6: After the pumping is completed, the temporary lowering boom is removed, and the pile head treatment, pile foundation inspection and foundation construction are carried out to complete the construction of the steel sheet pile and double-wall steel hanging box combined cofferdam.

8. The construction method of a steel sheet pile and double-walled steel hanging box combined cofferdam according to claim 7 is characterized by: After the construction of the combined cofferdam of steel sheet piles and double-walled steel hanging boxes is completed in step S6, the construction of the inner cap and pier body of the cofferdam is continued. After the construction of the inner cap and pier body of the combined cofferdam is completed, the diver dives to the connection device (5) to release the connection and dismantle the steel sheet pile cofferdam (4).

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