A well packer

Abstract

This utility model discloses a sealing method for dewatering wells, belonging to the field of pit dewatering technology. It includes a foundation, with a concrete well pipe installed inside the foundation. A concrete cushion layer is installed above the foundation, with the outer surface of the concrete well pipe in contact with the inner wall of the concrete cushion layer. A waterproof protective layer is installed above the concrete cushion layer, and a raft slab is installed above the waterproof protective layer. An installation hole is opened on the bottom surface of the raft slab, and a steel pipe is installed inside the installation hole. The bottom end of the steel pipe is fixedly connected to the top end of the concrete well pipe. This sealing method for dewatering wells improves the water-stopping effect and reduces seepage problems through the combination of the waterproof protective layer, raft slab, installation hole, and steel pipe. Furthermore, the use of a filling groove, flange, blind flange, square micro-expansion concrete, and columnar micro-expansion concrete, and the fit between the blind flange and flange, enhances the sealing effect of the blind flange on the dewatering well, thus improving the sealing effect of the dewatering well.

Description

Technical Field

[0001] This utility model relates to the field of engineering foundation pit dewatering technology, specifically to a dewatering well sealing method. Background Technology

[0002] Dewatering of a foundation pit refers to the work done when the groundwater level is higher than the bottom of the excavation pit during excavation, and groundwater will continuously seep into the pit. In order to ensure that the foundation pit can be constructed under dry conditions and to prevent slope instability, quicksand in the foundation, pit bottom heave, piping at the bottom of the pit, and a decrease in the bearing capacity of the foundation, the dewatering wells usually need to be sealed after the foundation pit is dewatered.

[0003] The existing utility model patent with authorization announcement number CN216238605U discloses a sealing device for dewatering wells, which can directly utilize construction waste for secondary use to ensure the sealing of dewatering wells. However, the above technology only uses the welding of annular water-stop steel plates to the upper sealing plate to improve the water-stopping effect of the dewatering well. This kind of dewatering well sealing operation is prone to water seepage problems, which will cause the water level in the dewatering well pit to rise rapidly, destroy the dry construction environment, and may lead to soil collapse and pit instability. The underground structure may crack and float due to excessive groundwater pressure, resulting in serious problems such as safety accidents.

[0004] Therefore, we propose a method of sealing dewatering wells to solve the above problems. Utility Model Content

[0005] The purpose of this invention is to solve the problem of poor sealing effect and easy water seepage in the existing technology, and to propose a method for sealing dewatering wells.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A dewatering well sealing method includes a foundation, a concrete well pipe installed inside the foundation, a concrete cushion layer installed above the foundation, the outer surface of the concrete well pipe contacting the inner wall of the concrete cushion layer, a waterproof protective layer installed above the concrete cushion layer, a raft slab installed above the waterproof protective layer, an installation hole opened on the bottom surface of the raft slab, a steel pipe installed inside the installation hole, the bottom end of the steel pipe being fixedly connected to the top end of the concrete well pipe, a filling groove opened on the upper surface of the raft slab, the filling groove communicating with the installation hole, a flange fixedly connected to the top end of the steel pipe, a blind flange installed above the flange, a square micro-expansion concrete installed inside the filling groove, the steel pipe, flange, and blind flange all being snapped into the square micro-expansion concrete, a columnar micro-expansion concrete being snapped into the interior of the concrete cushion layer and the interior of the steel pipe, the top end of the columnar micro-expansion concrete contacting the bottom surface of the blind flange.

[0007] Preferably, a water-stop ring is fixedly connected to the outer surface of the steel pipe, the inner wall of the water-stop ring is in contact with the outer surface of the concrete well pipe, and the outer surface, upper surface and bottom surface of the water-stop ring are in contact with the inner wall of the waterproof protective layer, the bottom surface of the raft slab and the upper surface of the concrete pad, respectively.

[0008] Preferably, a waterproof membrane is fixedly connected to the upper surface of the water-stop ring, and the inner wall of the waterproof membrane is fixedly connected to the outer surface of the steel pipe.

[0009] Preferably, a rubber pad is provided above the flange, the inner wall of the rubber pad is in contact with the outer surface of the cylindrical micro-expansion concrete, and the upper surface of the rubber pad is in contact with the bottom surface of the blind flange.

[0010] Preferably, both the flange and the rubber gasket have equidistant circumferentially arranged positioning holes.

[0011] Preferably, the bottom surface of the blind flange is fixedly connected with positioning rods arranged in a circular pattern at equal intervals, and the bottom end of the positioning rods passes through the positioning hole and extends to the bottom of the flange.

[0012] Preferably, a first corrosion-resistant layer is provided above the waterproof protective layer, and a second corrosion-resistant layer is provided below the waterproof protective layer.

[0013] Preferably, a first waterproof layer is disposed above the first corrosion-resistant layer, and a second waterproof layer is disposed below the second corrosion-resistant layer.

[0014] In summary, the technical effects and advantages of this utility model are as follows: By coordinating the installation of concrete well pipes, concrete foundation layers, waterproof protective layers, raft foundations, installation holes, and steel pipes, the steel pipes can be manually inserted to the position where they contact the top of the concrete well pipes. The waterproof protective layer can be used to waterproof the contact points between the concrete foundation layers, concrete well pipes, steel pipes, and raft foundations, improving the water-stopping effect of the dewatering well, reducing seepage problems, and preventing the water level in the dewatering well pit from rising rapidly, which could cause serious problems such as cracking and floating of the underground structure due to excessive groundwater pressure. By utilizing the combination of filling grooves, flanges, blind flanges, square micro-expansion concrete, and columnar micro-expansion concrete, flanges can be fixed on the steel pipe, and the blind flanges can be matched with the flanges. This improves the sealing effect of the blind flanges on the dewatering well. After the dewatering well is sealed, the water pump inside the concrete well pipe can be pulled out. The steel pipe and the concrete well pipe are then filled with columnar micro-expansion concrete. After the blind flange is sealed and no leakage is observed, square micro-expansion concrete is poured around the steel pipe to complete the sealing construction of the entire dewatering well, thereby improving the sealing effect of the dewatering well. Attached Figure Description

[0015] Figure 1This is a three-dimensional structural diagram of the square micro-expansion concrete of this utility model; Figure 2 This is a three-dimensional cross-sectional structural diagram of the concrete well pipe of this utility model; Figure 3 This is a three-dimensional structural diagram of the steel pipe of this utility model; Figure 4 This is a three-dimensional structural diagram of the raft plate of this utility model; Figure 5 This is a three-dimensional structural diagram of the rubber pad of this utility model; Figure 6 This is a cross-sectional view of the waterproof protective layer of this utility model.

[0016] In the diagram: 1. Foundation; 2. Concrete well pipe; 3. Concrete cushion layer; 4. Waterproof protective layer; 5. Water-stop ring; 6. Waterproof membrane; 7. Steel pipe; 8. Flange; 9. Positioning hole; 10. Blind flange; 11. Rubber gasket; 12. Positioning rod; 13. Raft foundation; 14. Mounting hole; 15. Filling groove; 16. Square micro-expansion concrete; 17. Columnar micro-expansion concrete; 18. First corrosion-resistant layer; 19. Second corrosion-resistant layer; 20. First waterproof layer; 21. Second waterproof layer. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0018] Reference Figure 1-6 A dewatering well sealing method includes a foundation 1, a concrete well pipe 2 installed inside the foundation 1, a concrete cushion layer 3 installed above the foundation 1, the outer surface of the concrete well pipe 2 contacting the inner wall of the concrete cushion layer 3, a waterproof protective layer 4 installed above the concrete cushion layer 3, a first corrosion-resistant layer 18 installed above the waterproof protective layer 4, and a second corrosion-resistant layer 19 installed below the waterproof protective layer 4. The first corrosion-resistant layer 18 and the second corrosion-resistant layer 19 are located on the outside of the waterproof protective layer 4. The first corrosion-resistant layer 18 and the second corrosion-resistant layer 19 are made of Teflon, which has extremely strong chemical stability, thereby improving the corrosion resistance of the waterproof protective layer 4.

[0019] A first waterproof layer 20 is provided above the first corrosion-resistant layer 18, and a second waterproof layer 21 is provided below the second corrosion-resistant layer 19. The first waterproof layer 20 and the second waterproof layer 21 are provided on the outside of the waterproof protective layer 4. The first waterproof layer 20 and the second waterproof layer 21 are made of polymer-modified asphalt, which can improve the waterproof performance of the waterproof protective layer 4.

[0020] A raft slab 13 is installed above the waterproof protective layer 4. An installation hole 14 is opened on the bottom surface of the raft slab 13. A steel pipe 7 is installed inside the installation hole 14. The bottom end of the steel pipe 7 is fixedly connected to the top end of the concrete well pipe 2. A water-stop ring 5 is fixed on the outer surface of the steel pipe 7. The inner wall of the water-stop ring 5 is in contact with the outer surface of the concrete well pipe 2. The outer surface, upper surface, and bottom surface of the water-stop ring 5 are in contact with the inner wall of the waterproof protective layer 4, the bottom surface of the raft slab 13, and the upper surface of the concrete pad 3, respectively. The water-stop ring 5 is installed on the outer surface of the steel pipe 7. The water-stop ring 5 is made of 5mm thick steel plate and welded to the steel pipe 7. The water-stop ring 5 improves the waterproof performance of the dewatering well.

[0021] A waterproof membrane 6 is fixed to the upper surface of the water-stop ring 5. The inner wall of the waterproof membrane 6 is fixedly connected to the outer surface of the steel pipe 7. When the waterproof membrane 6 is laid on the raft slab 13 cushion layer, it is turned up to the lower edge of the water-stop ring 5 at the position of the steel pipe 7, not less than 200mm. The upturned end of the waterproof membrane 6 is sealed with sealant between the steel pipe 7 and the water-stop ring 5 to further improve the waterproof performance of the dewatering well.

[0022] A filling groove 15 is provided on the upper surface of the raft plate 13. The filling groove 15 is connected to the mounting hole 14. A flange 8 is fixedly connected to the top of the steel pipe 7. A blind plate 10 is provided above the flange 8. A square micro-expansion concrete 16 is provided inside the filling groove 15. The steel pipe 7, flange 8 and blind plate 10 are all snapped into the inside of the square micro-expansion concrete 16. A columnar micro-expansion concrete 17 is snapped into the inside of the concrete pad 3 and the inside of the steel pipe 7. The top of the columnar micro-expansion concrete 17 is in contact with the bottom surface of the blind plate 10. A rubber gasket 11 is provided above the flange 8. The inner wall of the rubber gasket 11 is in contact with the outer surface of the columnar micro-expansion concrete 17. The upper surface of the rubber gasket 11 is in contact with the bottom surface of the blind plate 10. By using the rubber gasket 11 between the flange 8 and the blind plate 10, the sealing between the flange 8 and the blind plate 10 can be improved, thereby reducing water leakage between the flange 8 and the blind plate 10.

[0023] Both the flange 8 and the rubber gasket 11 have equidistantly arranged circumferential positioning holes 9. The bottom surface of the blind flange 10 is fixedly connected to equidistantly arranged circumferential positioning rods 12. The bottom ends of several positioning rods 12 pass through the positioning holes 9 in sequence and extend to the bottom of the flange 8. By using the multiple positioning rods 12 fixed to the bottom surface of the blind flange 10, the positioning rods 12 can pass through the positioning holes 9, thereby enabling the blind flange 10 on the flange 8 to be installed and positioned. Moreover, the positioning rods 12 can improve the reliability of the connection with the square micro-expansion concrete 16.

[0024] The working process of this utility model is as follows: When sealing a dewatering well, a number of concrete well pipes 2 are first installed approximately 1.0m above the existing water level in the foundation 1. The wells can be drilled to a depth of 600mm using an impact drill or excavator, and then the 300mm diameter concrete well pipes 2 are lowered. The concrete well pipes 2 extend to 3-4m below the bottom of the foundation 1. After filling the area around the concrete well pipes 2 with graded gravel, a sewage pump is lowered into the concrete well pipes 2 to pump water down to 0.5-1.0m below the bottom of the foundation 1. Then, during the construction of the main raft foundation 13, reinforced concrete well pipes are placed on top of the concrete well pipes 2. A steel pipe 7 with a diameter of 400mm and a wall thickness of 5mm is constructed. The opening of the steel pipe 7 is about 100mm below the surface of the proposed raft foundation 13. The waterproof membrane 6 under the raft foundation 13 is turned up at least 200mm above the position of the steel pipe 7. At the end of the upturned waterproof membrane 6, a water-stop ring 5 is installed around the concrete well pipe 2. The water-stop ring 5 is made of 5mm thick steel plate and is welded to the steel pipe 7. The contact gap between the water-stop ring 5 and the waterproof protective layer 4 of the lower waterproof membrane 6 is sealed with sealant. A flange 8 and a rubber gasket 11 are installed at the upper end of the steel pipe 7, so that the dewatering well can be sealed.

[0025] At this point, the pump inside the concrete well pipe 2 needs to be manually pulled out, so that the concrete well pipe 2 and the steel pipe 7 are quickly filled with cylindrical micro-expansion concrete 17, so that the blind flange 10 covers the rubber gasket 11, and the positioning rod 12 can be inserted into the positioning hole 9 opened on the rubber gasket 11 and the flange 8, until the rubber gasket 11 can pass through the flange 8 to the bottom of the flange 8, so that the blind flange 10 on the flange 8 can be positioned. After the blind flange 10 is sealed, observe for one week depending on the conditions. If there is no leakage, the micro-expansion concrete sealing construction can be carried out. If there is leakage, repair welding should be carried out immediately. After ensuring that there is no leakage, the micro-expansion concrete construction can be carried out. After the dewatering well is sealed and observed to have no water leakage, square micro-expansion concrete 16 is poured around the steel pipe 7 to complete the sealing construction of the entire dewatering well.

Claims

1. A well sealing method for dewatering wells, comprising a foundation (1), characterized in that: The foundation (1) is provided with a concrete well pipe (2), and a concrete cushion layer (3) is provided above the foundation (1). The outer surface of the concrete well pipe (2) is in contact with the inner wall of the concrete cushion layer (3). A waterproof protective layer (4) is provided above the concrete cushion layer (3), and a raft slab (13) is provided above the waterproof protective layer (4). An installation hole (14) is opened on the bottom surface of the raft slab (13), and a filling groove (15) is opened on the upper surface of the raft slab (13). The filling groove (15) is connected to the installation hole (14), and a square micro-expansion concrete is provided in the filling groove (15). 16), a steel pipe (7) is installed in the mounting hole (14). The bottom end of the steel pipe (7) is fixed to the top end of the concrete well pipe (2). A flange (8) is fixed to the top end of the steel pipe (7). A blind plate (10) is installed above the flange (8). The steel pipe (7), flange (8) and blind plate (10) are all clamped inside the square micro-expansion concrete (16). The inside of the concrete cushion layer (3) and the inside of the steel pipe (7) are clamped together with a columnar micro-expansion concrete (17). The top end of the columnar micro-expansion concrete (17) is in contact with the bottom surface of the blind plate (10).

2. The well sealing method for dewatering wells according to claim 1, characterized in that: A water-stop ring (5) is fixedly connected to the outer surface of the steel pipe (7). The inner wall of the water-stop ring (5) is in contact with the outer surface of the concrete well pipe (2). The outer surface of the water-stop ring (5), the upper surface of the water-stop ring (5), and the bottom surface of the water-stop ring (5) are in contact with the inner wall of the waterproof protective layer (4), the bottom surface of the raft (13), and the upper surface of the concrete cushion layer (3), respectively.

3. The well sealing method for dewatering wells according to claim 2, characterized in that: The upper surface of the water-stop ring (5) is fixed with a waterproof membrane (6), and the inner wall of the waterproof membrane (6) is fixedly connected to the outer surface of the steel pipe (7).

4. The well sealing method for dewatering wells according to claim 1, characterized in that: A rubber pad (11) is provided above the flange (8). The inner wall of the rubber pad (11) is in contact with the outer surface of the columnar micro-expansion concrete (17), and the upper surface of the rubber pad (11) is in contact with the bottom surface of the blind plate (10).

5. A method for sealing a dewatering well according to claim 4, characterized in that: Both the flange (8) and the rubber gasket (11) are provided with equidistant circumferentially arranged positioning holes (9).

6. The well sealing method for dewatering wells according to claim 5, characterized in that: The bottom surface of the blind plate (10) is fixedly connected with positioning rods (12) arranged in a circular pattern at equal intervals. The bottom end of the positioning rods (12) passes through the positioning hole (9) and extends to the bottom of the flange (8).

7. The well sealing method for dewatering wells according to claim 1, characterized in that: A first corrosion-resistant layer (18) is provided above the waterproof protective layer (4), and a second corrosion-resistant layer (19) is provided below the waterproof protective layer (4).

8. A method for sealing a dewatering well according to claim 7, characterized in that: A first waterproof layer (20) is provided above the first corrosion-resistant layer (18), and a second waterproof layer (21) is provided below the second corrosion-resistant layer (19).

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