Construction method of cofferdam structure without water cut-off and installation and removal of cofferdam without water cut-off

Abstract

The present invention discloses a non-stop water construction cofferdam structure, including a cofferdam structure with an open upper end, the construction side wall of the cofferdam structure includes an upper half wall, a connecting frame and a lower half wall welded in sequence from top to bottom in the same plane, the connecting frame encloses a working opening for construction, and the surface of the connecting frame facing the side wall of the water storage structure is provided with a water stop strip along the circumferential direction, the water stop strip is used to press the side wall of the water storage structure and seal the working opening; the connecting frames on the left and right sides of the construction side wall are respectively connected to hydraulic pressing mechanisms; the present invention also discloses a corresponding non-stop water installation and removal cofferdam construction method. The present invention is not only applicable to inclined water storage structure side walls, but also to vertical water storage structure side walls. Compared with the structure that relies on its own weight to achieve sealing with the side wall of the water storage structure, it has a wider adaptability, and is low in cost and easy to install and disassemble.

Description

Technical Field

[0001] This invention relates to the repair (opening) of cofferdams for water tanks and water conveyance channels without interrupting water supply, specifically to the construction method of circular arc steel plate cofferdams and their installation and dismantling without interrupting water supply. Background Technology

[0002] During the operation of water storage structures such as pumping stations, water plants, and canals, according to the design requirements of later projects, it is necessary to install water distribution outlets (gates, pipes, etc.) or perform leak sealing and repair work in the walls of water storage structures such as concrete pool walls and canal concrete straight walls without interrupting water supply.

[0003] The current method for installing water distribution outlets by opening holes in the walls of pressurized concrete pools in my country mainly involves first stopping the water supply in sections, then using flat steel cofferdams for protection, followed by opening the concrete and sealing the leaks, and finally removing the cofferdams to restore water supply.

[0004] Water plants, reservoirs, and water supply channels are related to the safety of people's water supply. Temporary water outages due to construction can cause significant economic losses and social impacts. Currently, flat-plate cofferdams are not only costly to process, install, and dismantle, but also have long construction cycles, increasing the duration of temporary water outages.

[0005] When designing the cofferdam structure for non-stop water supply construction, the applicant initially considered a structure that relies on its own weight and the sidewalls of the water storage structure to achieve a seal. The drawbacks of this structure are twofold: first, its weight is too great, otherwise it would be insufficient to form a seal between the cofferdam structure and the sidewalls of the water storage structure; second, it is only suitable for inclined sidewalls of water storage structures. For vertical or near-vertical sidewalls, no matter how heavy the cofferdam is, it cannot rely on its own weight to compress the sidewalls, thus failing to form a seal. The first drawback further leads to higher material costs, difficulties in manufacturing, transportation, installation, and dismantling, and lower installation and dismantling efficiency. Summary of the Invention

[0006] The purpose of this invention is to provide a cofferdam structure that is simple and lightweight, low in cost, highly efficient in installation and dismantling, and applicable to the side walls of both vertical and inclined water storage structures, allowing for non-stop construction.

[0007] To achieve the above objectives, the non-stop construction cofferdam structure of the present invention includes a cofferdam structure with an open upper end. The cofferdam structure includes a construction sidewall for adhering to the sidewall of the water storage structure to be constructed, a retaining sidewall of the same height as the construction sidewall, and a bottom plate. The construction sidewall, the retaining sidewall, and the bottom plate are connected to each other to form the cofferdam structure.

[0008] The construction sidewall comprises an upper half wall, a connecting frame, and a lower half wall welded sequentially from top to bottom in the same plane. The connecting frame forms a working opening for construction. The widths of the retaining sidewall, upper half wall, lower half wall, and working opening are the same. The top of the upper half wall is flush with the top of the retaining sidewall, and the lower half wall is 500±200 mm high. A waterstop strip is provided circumferentially on the surface of the connecting frame facing the sidewall of the water storage structure. The waterstop strip is used to press the sidewall of the water storage structure and seal the working opening.

[0009] The connecting frames on the left and right sides of the construction sidewall are respectively connected to hydraulic clamping mechanisms;

[0010] The hydraulic clamping mechanism includes a hydraulic cylinder, and the extension rod of the hydraulic cylinder is fixedly connected to an extension rod arranged on the same axis. The upper end of the extension rod is hinged to the connecting frame.

[0011] The lower end of the hydraulic cylinder is hinged with an anti-slip steel shoe, which is used to support the bottom wall of the water storage structure; the angle between the axis of the hydraulic cylinder's extension rod and the vertical line is 15±5 degrees.

[0012] The construction sidewalls, retaining sidewalls, and bottom plate of the cofferdam structure are all made of steel and are welded together; the extension rod is made of steel pipe and is welded to the extension rod of the hydraulic cylinder.

[0013] The anti-slip steel boot includes a horizontal steel plate, with a hinged bushing connected upwards to the horizontal steel plate. The hinged bushing is hinged to the lower end of the cylinder body of the hydraulic cylinder. The horizontal steel plate is connected downwards to anti-slip teeth made of metal, which are used to support the bottom wall of the water storage structure. The horizontal cross-section of the cofferdam structure is semi-circular.

[0014] The waterstop strip adopts a P-type waterstop strip, which has a cavity inside. The cavity of the P-type waterstop strip is connected to a vent pipe, which is connected to an air compressor. An air valve is installed on the vent pipe. Both sets of hydraulic clamping mechanisms are connected to the hydraulic control system, which is used to control the synchronous operation of the two sets of hydraulic clamping mechanisms.

[0015] The inner surface of the enclosure sidewall is provided with reinforcing ribs.

[0016] This invention also provides a construction method for the installation and dismantling of a cofferdam without interrupting water flow using the above-mentioned cofferdam structure, which is carried out according to the following steps:

[0017] The first step is processing;

[0018] The first step includes the processing of waterstop strips, anti-slip steel boots, hydraulic cylinders, construction sidewalls of the cofferdam structure, retaining sidewalls of the cofferdam structure, and bottom plate of the cofferdam structure, which are carried out in no particular order.

[0019] The processing of waterstop strips involves cutting P-type waterstop strips with a circumferential length equal to that of the connecting frame;

[0020] The second step is assembly;

[0021] The construction sidewalls, retaining sidewalls, and bottom plate of the cofferdam structure are welded together to form a cofferdam structure with an open top.

[0022] A pressure plate is attached to the P-type waterstop strip around the connecting frame of the construction side wall. Bolts are passed through the pressure plate and the P-type waterstop strip and threadedly connected to the connecting frame. Tightening the bolts presses the P-type waterstop strip onto the connecting frame. The hollow part inside the P-type waterstop strip is located outside the pressure plate and is used to seal against the side wall of the water storage structure. One bolt is set on the pressure plate every 300 mm.

[0023] The bottom end of the hydraulic cylinder body is hinged to the anti-slip steel shoe through the hinge bushing of the anti-slip steel shoe, and the end of the extension rod is hinged to the connecting frame.

[0024] A cable is connected between the anti-slip steel boot and the top of the construction sidewall or the top of the retaining sidewall, and the angle between the axis of the hydraulic cylinder extension rod and the vertical line is within the range of 15±5 degrees through the cable; preferably, a connecting ring is welded to the top of the construction sidewall or the top of the retaining sidewall, and a cable is connected between the connecting ring and the anti-slip steel boot.

[0025] The third step is to launch and position the cofferdam.

[0026] Mark the location on the side wall of the water storage structure that needs to be opened or repaired, and mark the water depth and water entry position of the cofferdam structure. Drill holes on the side wall of the water storage structure at the upper position of the construction side wall of the predetermined cofferdam structure, and insert the expansion tube of the expansion bolt.

[0027] After the entire cofferdam structure is lifted by a crane and lowered into the water, the lowering continues until the anti-slip steel boots touch the bottom. The lowering continues until the P-type waterstop strip at the connecting frame is tightly attached to the side wall of the water storage structure and the cofferdam structure no longer falls under the action of gravity. Then the lowering action is stopped and the crane releases the cofferdam structure.

[0028] The fourth step is reinforcement;

[0029] Expansion bolts are used to pass through the construction sidewall of the cofferdam structure and extend into the expansion pipe. The expansion bolts are then tightened to fix the upper part of the cofferdam structure to the sidewall of the water storage structure.

[0030] The hydraulic cylinders of the two hydraulic clamping mechanisms are activated by the hydraulic control system, so that the extension rods of the two hydraulic cylinders extend synchronously, pressing the construction side wall of the cofferdam structure and the P-type waterstop strip tightly onto the side wall of the water storage structure, forming a seal around the working opening.

[0031] The fifth step is pumping water;

[0032] By using submersible pumps to pump water out of the cofferdam structure, the water level in the cofferdam structure is lower than the lower end of the working opening. At this time, workers can carry out construction work such as opening or maintenance on the side wall of the water storage structure inside the cofferdam, so as to achieve construction without stopping the water supply.

[0033] The processing of the retaining sidewalls of the cofferdam structure is as follows: the finished steel pipe or the steel plate is processed into a cylinder using a plate rolling machine, and the finished steel pipe or cylinder is divided into two halves along the axis to form two retaining sidewalls of the cofferdam structure. The cross section of the retaining sidewall of each cofferdam structure is semi-circular arc-shaped.

[0034] The construction sidewall fabrication of the cofferdam structure involves welding the upper half wall, connecting frame, and lower half wall sequentially from top to bottom in the same plane to form the construction sidewall.

[0035] The bottom plate of the cofferdam structure is fabricated by cutting a flat steel plate into a semi-circular arc shape that matches the retaining sidewall of the cofferdam structure;

[0036] Hydraulic cylinder machining involves coaxially welding an extension rod made of steel pipe onto the extension rod of the hydraulic cylinder.

[0037] The anti-slip steel boot manufacturing process involves first producing a square steel plate, then welding a hinged bushing to the upper surface of the square steel plate, and welding 3-5 anti-slip steel teeth to the lower surface of the square steel plate; the preferred dimensions of the square steel plate are 200 mm × 200 mm × 10 mm.

[0038] It also includes a sixth step, which is the dismantling of the cofferdam;

[0039] After the construction of the side wall of the water storage structure is completed, the hydraulic cylinders of the two hydraulic clamping mechanisms are activated through the hydraulic control system, so that the extension rods of the two hydraulic cylinders retract synchronously. The P-type waterstop strip no longer presses tightly against the side wall of the water storage structure, thus losing its sealing function. The expansion bolts on the upper part of the cofferdam structure are removed. After water is injected into the cofferdam structure at the working opening until the water surface inside and outside the cofferdam structure is level, the cofferdam structure is lifted as a whole by a crane to complete the cofferdam demolition work.

[0040] In the fifth step, when the staff observes that the water leakage at the working opening is serious and the water level may rise to the working opening within the time required for construction, the staff opens the air valve and turns on the air compressor to inflate the cavity of the P-type waterstop strip, so that the P-type waterstop strip expands and thus improves the sealing degree at the working opening; after the P-type waterstop strip expands, the air valve and air compressor are closed.

[0041] In the fifth step, if after the cavity of the P-type waterstop is inflated, the staff still observes severe leakage at the working opening and the water level may rise to the working opening within the time required for construction, the staff will install a small-flow submersible pump inside the cofferdam structure and start the small-flow start-up pump to continuously drain the accumulated water inside the cofferdam structure until the construction is completed; the drainage speed of the small-flow submersible pump is matched with the leakage speed at the working opening.

[0042] The present invention has the following advantages:

[0043] If a hydraulic cylinder (jack) is used underwater, with one end (such as the cylinder body) resting against an underwater backrest structure parallel or nearly parallel to the sidewall of the water-storage structure to be constructed, and the other end (such as the extension rod) resting against the cofferdam structure, a horizontal force can be applied to the cofferdam structure to compress the sidewall of the water-storage structure. This creates a seal between the cofferdam structure and the sidewall of the water-storage structure, allowing water to be pumped out and construction to proceed within the cofferdam. However, it is difficult to find an underwater backrest structure parallel or nearly parallel to the sidewall of the water-storage structure to be constructed precisely near the sidewall of the water-storage structure.

[0044] Using the structure of this invention, without the need for an underwater backrest structure, the cofferdam structure can be easily pressed tightly against the side wall of the water storage structure to form a seal through a hydraulic cylinder, thus eliminating the dependence on an underwater backrest structure and making it suitable for the construction of the side wall of any water storage structure.

[0045] The hydraulic cylinder applies force to the connecting frame via its extension rod, creating a vertical component along the side wall of the water storage structure and a horizontal component perpendicular to the side wall. When the side wall of the water storage structure is vertical or nearly vertical, the angle between the axis of the hydraulic cylinder's extension rod and the plumb line is 15±5 degrees, ensuring that the vertical component is much greater than the horizontal component. This guarantees that the friction between the anti-slip steel shoe and the bottom wall of the water storage structure is greater than the horizontal component, preventing the anti-slip steel shoe from moving away from the side wall under the reaction force of the horizontal component. This ensures that the horizontal component is not too small or even disappears, utilizing sufficient horizontal force to produce a better sealing effect.

[0046] In summary, the angle between the axis of the hydraulic cylinder's extension rod and the vertical line is 15±5 degrees, which can prevent the anti-slip steel boot from slipping and ensure sufficient clamping force (horizontal component) to maintain the seal at the working opening.

[0047] This invention can expand the P-type waterstop strip by inflating it with air, thereby improving the sealing performance at the working opening.

[0048] The construction method for installing and dismantling a cofferdam without interrupting water supply, as described in this invention, is simple in steps, the cofferdam structure is easy to manufacture, install and dismantle, and the cofferdam structure can be repeatedly used in the construction of different water storage structures, thus reducing construction costs.

[0049] The drainage speed of the small-flow submersible pump matches the leakage speed at the working opening, enabling construction to proceed while pumping water, further reducing the precision required in the project. Even if the P-type waterstop does not perform well in sealing, construction can still be carried out without interrupting water flow.

[0050] This invention is applicable not only to inclined sidewalls of water storage structures but also to vertical sidewalls of water storage structures. Compared to structures that rely on their own weight and the sidewalls of water storage structures to achieve a seal (which is not applicable to vertical sidewalls of water storage structures), it has wider applicability and is low in cost and easy to install and disassemble. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the cofferdam structure for non-stop water supply construction according to the present invention;

[0052] Figure 2 yes Figure 1 Top view;

[0053] Figure 3 yes Figure 2 Enlarged view of point B in the middle;

[0054] Figure 4 yes Figure 1 Enlarged view of point A in the middle;

[0055] Figure 5 yes Figure 1 A schematic diagram of the right-side structure of the side wall under construction. Detailed Implementation

[0056] like Figures 1 to 5 As shown, the non-stop construction cofferdam structure of the present invention includes a cofferdam structure with an open upper end. The cofferdam structure includes a construction sidewall 1 for attaching to the sidewall 5 of the water storage structure to be constructed, a retaining sidewall 2 of the same height as the construction sidewall 1, and a bottom plate 3. The construction sidewall 1, the retaining sidewall 2, and the bottom plate 3 are connected to each other to form a cofferdam structure.

[0057] The construction sidewall 1 includes an upper half wall 101, a connecting frame 4, and a lower half wall 102 welded sequentially from top to bottom in the same plane. The connecting frame 4 forms a working opening 6 for construction. The widths of the enclosure sidewall 2, the upper half wall 101, the lower half wall 102, and the working opening 6 are the same. The top of the upper half wall 101 is flush with the top of the enclosure sidewall 2. The lower half wall 102 is 500±200 mm high (the height of the lower half wall 102 is the maximum depth for water accumulation and pumping). A waterstop strip is provided circumferentially on the surface of the connecting frame 4 facing the sidewall 5 of the water storage structure. The waterstop strip is used to press the sidewall of the water storage structure and seal the working opening 6.

[0058] The connecting frame 4 is preferably a square frame, but other shapes (such as circular or elliptical) can also be used. It can be made of channel steel or angle steel. The working opening 6 is located in... Figure 1 The opening 8 is located directly opposite the side wall of the water storage structure. Figure 1 The design water level is indicated by number 9.

[0059] Hydraulic clamping mechanisms are connected to the connecting frames 4 on the left and right sides of the construction side wall 1, respectively.

[0060] The hydraulic clamping mechanism includes a hydraulic cylinder 10 (a jack is one type of hydraulic cylinder 10, preferably a 5-ton jack), and the extension rod of the hydraulic cylinder 10 is fixedly connected to an extension rod 11 arranged coaxially. The upper end of the extension rod 11 is hinged to the connecting frame 4. Specifically, the connecting frame 4 is preferably made of channel steel, and the upper end of the extension rod 11 is hinged to the channel steel structure through a hinge shaft.

[0061] The lower end of the cylinder body of the hydraulic cylinder 10 is hinged with an anti-slip steel shoe, which is used to support the bottom wall of the water storage structure (such as the bottom of a pool); the angle between the axis of the extension rod of the hydraulic cylinder 10 and the vertical line is 15±5 degrees (including 10 degrees and 20 degrees).

[0062] In this invention, the hydraulic system preferably uses pure water instead of hydraulic oil to avoid water pollution.

[0063] Specifically, the construction sidewall 1, the retaining sidewall 2, and the bottom plate 3 of the cofferdam structure are all made of steel and are all 5-10 mm thick. The construction sidewall 1, the retaining sidewall 2, and the bottom plate are welded together. The extension rod 11 is a steel pipe (preferably a steel pipe with a diameter of 110 mm), and the extension rod 11 is welded to the extension rod of the hydraulic cylinder 10.

[0064] The anti-slip steel boot includes a horizontal steel plate 12, with a hinged bushing 13 connected upward to the horizontal steel plate 12. The hinged bushing 13 is hinged to the lower end of the cylinder body of the hydraulic cylinder 10. The horizontal steel plate 12 is connected downward to anti-slip teeth 14 made of metal. The anti-slip teeth 14 are used to support the bottom wall of the water storage structure. The horizontal cross section of the cofferdam structure is semi-circular.

[0065] The waterstop strip 7 is a P-type waterstop strip. The P-type waterstop strip has a cavity 15 inside. The cavity 15 of the P-type waterstop strip is connected to a vent pipe, which is connected to an air compressor. An air valve is provided on the vent pipe. Both sets of hydraulic clamping mechanisms are connected to the hydraulic control system. The hydraulic control system is used to control the synchronous operation of the two sets of hydraulic clamping mechanisms.

[0066] The inner surface of the enclosure sidewall 2 is reinforced with angle steel ribs. The ribs, vent pipes, and air compressor are all conventional components and are not shown in the figure.

[0067] This invention also discloses a construction method for installing and dismantling a cofferdam without interrupting water flow using the aforementioned cofferdam structure, which is carried out according to the following steps:

[0068] The first step is processing;

[0069] The first step includes the processing of waterstop strip 7, anti-slip steel boot, hydraulic cylinder 10, construction side wall 1 of the cofferdam structure, retaining side wall 2 of the cofferdam structure, and bottom plate 3 of the cofferdam structure, which are carried out in no particular order.

[0070] The processing of waterstop strip 7 involves cutting a P-type waterstop strip with a circumferential length equal to that of the connecting frame 4;

[0071] The second step is assembly;

[0072] The construction sidewall 1 of the cofferdam structure (including the upper half wall 101, the connecting frame 4 made of channel steel and the lower half wall 102), the retaining sidewall 2 of the cofferdam structure and the bottom plate of the cofferdam structure are welded to form a cofferdam structure with an open upper end.

[0073] A pressure plate 17 is attached to a P-type waterstop strip around the connecting frame 4 surrounding the construction side wall 1. Bolts 16 are threaded through the pressure plate 17 and the P-type waterstop strip and connected to the connecting frame 4. Tightening the bolts 16 presses the P-type waterstop strip onto the connecting frame 4. The cavity 15 inside the P-type waterstop strip is located outside the pressure plate 17 and is used for sealing with the side wall 5 of the water storage structure. One bolt 16 is provided on the pressure plate 17 every 300 mm.

[0074] The bottom end of the cylinder body of the hydraulic cylinder 10 is hinged to the anti-slip steel shoe through the hinge bushing 13 of the anti-slip steel shoe, and the end of the extension rod 11 is hinged to the connecting frame 4 through the hinge shaft.

[0075] A cable 19 is connected between the anti-slip steel boot and the top of the construction side wall 1 or the top of the enclosure side wall 2. The angle between the axis of the extension rod of the hydraulic cylinder 10 and the vertical line is within the range of 15±5 degrees through the cable 19. Preferably, a connecting ring 18 is welded to the top of the construction side wall 1 or the top of the enclosure side wall 2, and the cable 19 is connected between the connecting ring 18 and the anti-slip steel boot.

[0076] The third step is to launch and position the cofferdam.

[0077] Mark the location on the side wall 5 of the water storage structure that needs to be opened or repaired, mark the water depth and water entry position of the cofferdam structure, drill holes on the side wall 5 of the water storage structure at the upper position of the construction side wall 1 of the predetermined cofferdam structure, and insert the expansion tube of the expansion bolt.

[0078] After the cofferdam structure is lifted as a whole by a crane, it is lowered into the water. After the anti-slip steel boots touch the bottom (the angle refers to the bottom wall of the water storage structure), the lowering continues until the P-type waterstop strip at the connecting frame is tightly attached to the side wall of the water storage structure and the cofferdam structure no longer falls under the action of gravity. Then the lowering action is stopped and the crane releases the cofferdam structure.

[0079] The fourth step is reinforcement;

[0080] Use expansion bolts to pass through the construction sidewall 1 of the cofferdam structure and extend into the expansion pipe, and tighten the expansion bolts to fix the upper part of the cofferdam structure to the sidewall 5 of the water storage structure.

[0081] The hydraulic cylinders 10 of the two hydraulic clamping mechanisms are activated by the hydraulic control system, so that the extension rods 11 of the two hydraulic cylinders 10 extend synchronously, pressing the construction side wall 1 of the cofferdam structure and the P-type waterstop strip onto the side wall 5 of the water storage structure, forming a seal around the working opening 6.

[0082] The fifth step is pumping water;

[0083] A high-flow submersible pump is used to pump out the water from the cofferdam structure, so that the water level in the cofferdam structure is lower than the lower end of the working opening 6. At this time, the workers can carry out construction work such as opening or maintenance on the side wall 5 of the water storage structure inside the cofferdam, so as to achieve construction without stopping the water supply.

[0084] The processing of the retaining sidewall 2 of the cofferdam structure is as follows: using finished steel pipes of predetermined size or using a plate rolling machine to process steel plates of predetermined size into cylinders, the finished steel pipes or cylinders are divided into two halves along the axis to form two retaining sidewalls 2 of the cofferdam structure, and the cross section of the retaining sidewall 2 of each cofferdam structure is semi-circular arc-shaped.

[0085] The construction sidewall 1 of the cofferdam structure is fabricated by welding the upper half wall 101, the connecting frame 4 and the lower half wall 102 from top to bottom in the same plane to form the construction sidewall 1.

[0086] The bottom plate of the cofferdam structure is fabricated by cutting a flat steel plate into a semi-circular arc shape that matches the retaining sidewall 2 of the cofferdam structure;

[0087] The machining of hydraulic cylinder 10 involves coaxially welding an extension rod 11 made of steel pipe (110 mm in diameter) onto the extension rod of hydraulic cylinder 10 (specifically a 5-ton jack);

[0088] The anti-slip steel boot processing (making two sets of anti-slip steel boots) involves first making a square steel plate, then welding a hinged bushing 13 to the upper surface of the square steel plate, and welding 3-5 (including the two ends) anti-slip steel teeth to the lower surface of the square steel plate; the preferred size of the square steel plate is 200 mm × 200 mm × 10 mm.

[0089] It also includes a sixth step, which is the dismantling of the cofferdam;

[0090] After the construction (opening or maintenance) at point 5 on the side wall of the water storage structure is completed, the hydraulic cylinders 10 of the two hydraulic clamping mechanisms are activated through the hydraulic control system, so that the extension rods 11 of the two hydraulic cylinders 10 retract synchronously. The P-type waterstop strip no longer presses tightly against the side wall 5 of the water storage structure, thus losing its sealing function. Remove the expansion bolts on the upper part of the cofferdam structure. After water is injected into the cofferdam structure at the working opening 6 until the water levels inside and outside the cofferdam structure are level, use a crane to lift the cofferdam structure as a whole to complete the cofferdam demolition work.

[0091] In the fifth step, when the workers observe severe leakage at working opening 6 and the water level is likely to rise to working opening 6 within the required construction time, the workers open the air valve and start the air compressor to inflate the cavity 15 of the P-type waterstop strip, causing the P-type waterstop strip to expand and thus improve the sealing degree at the working opening; after the P-type waterstop strip expands, the air valve and air compressor are closed. The exhaust pressure of the air compressor is 2 MPa.

[0092] In the fifth step, if after the cavity 15 of the P-type waterstop is inflated, the staff still observes severe leakage at the working opening 6, and the water level may rise to the working opening 6 within the time required for construction, the staff will install a small-flow submersible pump (relative to the larger flow rate of the submersible pump used during the first pumping) inside the cofferdam structure and start the small-flow start-up pump to continuously drain the accumulated water inside the cofferdam structure until the construction is completed; the drainage speed of the small-flow submersible pump is matched with the leakage speed at the working opening 6.

[0093] The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention without departing from the spirit and scope of the present invention. Any modifications or partial substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A non-water-stopping construction cofferdam structure, including a cofferdam structure with an open upper end, the cofferdam structure including a construction side wall for contacting with the side wall of a water storage structure to be constructed, a protective side wall having the same height as the construction side wall, and a bottom plate, wherein the construction side wall, the protective side wall and the bottom plate are connected to each other to form a cofferdam structure; characterized in that: The construction side wall includes an upper half wall, a connecting frame and a lower half wall which are welded in sequence from top to bottom in the same plane. The connecting frame encloses a working opening for construction. The widths of the enclosure side wall, the upper half wall, the lower half wall and the working opening are the same. The top of the upper half wall is flush with the top of the enclosure side wall, and the height of the lower half wall is 500±200 mm. The surface of the connecting frame facing the side wall of the water storage structure is provided with a water stop strip along the circumferential direction. The water stop strip is used to press the side wall of the water storage structure and seal the working opening. The connection frames on the left and right sides of the construction side wall are respectively connected with hydraulic clamping mechanisms; The hydraulic pressing mechanism comprises a hydraulic cylinder, the extension rod of the hydraulic cylinder is fixedly connected to an extension rod arranged coaxially, and the upper end of the extension rod is hinged to the connecting frame; The lower end of the hydraulic cylinder is hinged with an anti-skid steel shoe, which is used to support the bottom wall of the water storage structure; the angle between the axis of the extension rod of the hydraulic cylinder and the plumb line is 15±5 degrees; The construction side wall, the enclosure side wall and the bottom plate of the cofferdam structure are all made of steel, and the construction side wall, the enclosure side wall and the bottom plate are welded together; the extension rod is a steel pipe, and the extension rod is welded to the extension rod of the hydraulic cylinder; The anti-skid steel boots include a horizontal steel plate, which is upwardly connected to a hinged sleeve, which is hinged to the lower end of the cylinder body of the hydraulic cylinder; the horizontal steel plate is downwardly connected to anti-skid teeth made of metal, which are used to support the bottom wall of the water storage structure; the horizontal section of the cofferdam structure is in the shape of a semicircular arch; The waterstop strip adopts a P-type waterstop strip, which has a cavity inside. The cavity of the P-type waterstop strip is connected to a ventilation pipe, and the ventilation pipe is connected to an air compressor; an air valve is provided on the ventilation pipe; both sets of hydraulic clamping mechanisms are connected to the hydraulic control system, and the hydraulic control system is used to control the synchronous action of the two sets of hydraulic clamping mechanisms.

2. The non-water-stopping construction cofferdam structure according to claim 1 is characterized by: The inner surface of the enclosing side wall is provided with reinforcing ribs.

3. A construction method for installing and removing a cofferdam without water stopping using the cofferdam structure without water stopping as described in claim 1, characterized in that Follow these steps: The first step is processing; The first step includes the processing of water stop strips, anti-skid steel boots, hydraulic cylinders, construction side walls of the cofferdam structure, protection side walls of the cofferdam structure, and bottom plates of the cofferdam structure in no particular order; The water stop strip processing is to cut a P-type water stop strip with the same circumferential length as the connection frame; The second step is assembly; The construction side wall of the cofferdam structure, the retaining side wall of the cofferdam structure and the bottom plate of the cofferdam structure are welded to form a cofferdam structure with an open upper end; The connection frame surrounding the construction side wall is attached to the P-type water stop strip using a pressure plate, and bolts are passed through the pressure plate and the P-type water stop strip and threadedly connected to the connection frame, and the bolts are tightened to press the P-type water stop strip onto the connection frame; the cavity portion in the P-type water stop strip is located outside the pressure plate and is used to seal with the side wall of the water storage structure; the pressure plate is provided with a bolt every 300 mm; The bottom end of the cylinder body of the hydraulic cylinder is hinged to the anti-skid steel shoe through the hinged shaft sleeve of the anti-skid steel shoe, and the end of the extension rod is hinged to the connecting frame; A cable is connected between the anti-slip steel boot and the top of the construction side wall or the top of the enclosure side wall, and the angle between the axis of the extension rod of the hydraulic cylinder and the plumb line is within the range of 15±5 degrees through the cable; The third step is to launch the cofferdam into place; Mark the side wall of the water storage structure that needs to be opened or repaired, mark the water entry depth and water entry position of the cofferdam structure, drill holes on the side wall of the water storage structure at the upper position of the construction side wall of the predetermined cofferdam structure, and insert the expansion tube of the expansion bolt; Use a crane to lift the cofferdam structure as a whole and lower it into the water. Continue lowering it after the anti-slip steel boots touch the bottom until the P-type water stop strip at the connection frame is close to the side wall of the water storage structure and the cofferdam structure no longer falls under the action of gravity. Then stop lowering and let the crane release the cofferdam structure; The fourth step is reinforcement; Use expansion bolts to pass through the construction side wall of the cofferdam structure and extend into the expansion pipe, and tighten the expansion bolts to fix the upper part of the cofferdam structure to the side wall of the water storage structure; The hydraulic cylinders of the two sets of hydraulic clamping mechanisms are activated through the hydraulic control system, so that the extension rods of the two hydraulic cylinders are extended synchronously, and the construction side wall of the cofferdam structure and the P-type water stop strip are pressed tightly against the side wall of the water storage structure to form a seal around the working opening; The fifth step is pumping; Use a submersible pump to pump out the water in the cofferdam structure so that the water level in the cofferdam structure is lower than the lower end of the working opening. At this time, the staff can open or maintain the side wall of the water storage structure in the cofferdam to achieve construction without stopping the water supply.

4. The construction method for installing and removing a cofferdam without stopping water supply according to claim 3 is characterized in that: The processing of the retaining side wall of the cofferdam structure is: the finished steel pipe or the steel plate is processed into a cylinder by a plate rolling machine, and the finished steel pipe or the cylinder is divided into two halves along the axis to form the retaining side walls of the two cofferdam structures, and the cross section of the retaining side wall of each cofferdam structure is a semicircular arch; The construction side wall processing of the cofferdam structure is: welding the upper half wall, the connecting frame and the lower half wall from top to bottom in the same plane to form the construction side wall; The bottom plate processing of the cofferdam structure is to cut a flat steel plate into a semicircular arch shape that matches the retaining side wall of the cofferdam structure; The hydraulic cylinder processing is to coaxially weld an extension rod made of steel pipe on the extension rod of the hydraulic cylinder; The processing of anti-skid steel boots is to first make a square steel plate, then weld a hinged sleeve on the upper surface of the square steel plate, and weld 3-5 anti-skid steel teeth on the lower surface of the square steel plate; the size of the square steel plate is 200 mm × 200 mm × 10 mm.

5. The construction method for installing and removing a cofferdam without stopping water supply according to claim 3 is characterized in that: Also included is a sixth step, which is the removal of the cofferdam; After the construction on the side wall of the water storage structure is completed, the hydraulic cylinders of the two sets of hydraulic clamping mechanisms are started through the hydraulic control system, so that the extension rods of the two hydraulic cylinders are retracted synchronously, and the P-type water stop strips no longer press the side wall of the water storage structure and lose their sealing effect; the expansion bolts on the upper part of the cofferdam structure are removed, and after water is injected into the cofferdam structure at the working opening until the water surfaces inside and outside the cofferdam structure are flush, the cofferdam structure is lifted as a whole by a crane to complete the cofferdam removal work.

6. The construction method for installing and removing a cofferdam without stopping water supply according to claim 5 is characterized in that: In the fifth step, when the staff observes that there is serious water leakage at the working opening and the water level may rise to the working opening within the time required for construction, the staff opens the air valve and turns on the air compressor to inflate the cavity of the P-type water stop strip to expand the P-type water stop strip and thereby improve the sealing degree of the working opening; after the P-type water stop strip expands, close the air valve and the air compressor.

7. The construction method for installing and removing a cofferdam without stopping water supply according to claim 6 is characterized in that: In the fifth step, if after the cavity of the P-type water stop strip is inflated, the staff still observes serious water leakage at the working opening and the water level may rise to the working opening within the time required for construction, the staff will install a small-flow submersible pump in the cofferdam structure and start the small-flow submersible pump to continuously drain the accumulated water in the cofferdam structure until the construction is completed; the drainage speed of the small-flow submersible pump matches the water leakage speed at the working opening.

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