CN116537238A - Plugging method for dry well under water-carrying operation environment - Google Patents
Plugging method for dry well under water-carrying operation environment Download PDFInfo
- Publication number
- CN116537238A CN116537238A CN202310808023.4A CN202310808023A CN116537238A CN 116537238 A CN116537238 A CN 116537238A CN 202310808023 A CN202310808023 A CN 202310808023A CN 116537238 A CN116537238 A CN 116537238A
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- Prior art keywords
- well
- pipe
- plugging
- drain
- drainage
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Links
- 238000000034 method Methods 0.000 title claims abstract description 28
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 58
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 43
- 239000010959 steel Substances 0.000 claims abstract description 43
- 238000005086 pumping Methods 0.000 claims abstract description 23
- 238000010276 construction Methods 0.000 claims abstract description 16
- 239000002689 soil Substances 0.000 claims abstract description 14
- 238000003466 welding Methods 0.000 claims abstract description 11
- 238000007789 sealing Methods 0.000 claims abstract description 7
- 239000003673 groundwater Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D19/00—Keeping dry foundation sites or other areas in the ground
- E02D19/06—Restraining of underground water
- E02D19/10—Restraining of underground water by lowering level of ground water
Abstract
The plugging method of the dry well in the water-carrying operation environment comprises the following steps: step one, welding a plugging plate in the well pipe, and pumping out water above the plugging plate. Inserting the lower end of the well pipe into the drainage well, and filling a sealing ring in a gap between the well pipe and the drainage well. And thirdly, welding an annular water stop on the outer wall of the well pipe. And step four, inserting the drainage steel pipe into the well pipe. And fifthly, installing a butterfly valve at the upper end of the drainage steel pipe. Step six, installing an upper port section of the drain pipe with a top cover at the upper port of the butterfly valve, connecting the water pumping device with the upper port of the upper port section of the drain pipe, opening the butterfly valve to perform water pumping operation, closing the butterfly valve and withdrawing the water pumping device after the underground water level reaches the requirement. And seventh, pouring the expansion concrete, and welding a well cover on the top of the well pipe. And eighth, sequentially constructing a concrete cushion layer and a concrete bottom plate on the top of the soil body. The invention solves the technical problems of high plugging construction difficulty and easy water leakage phenomenon of the traditional plugging method.
Description
Technical Field
The invention belongs to the technical field of civil engineering construction, and particularly relates to a plugging method of a dry well in a water-carrying operation environment.
Background
Along with the continuous development of urban construction, the problem of groundwater can often be encountered in the deep foundation construction, in the underground engineering construction process, in order to reduce the adverse effect that the groundwater level is too high to the construction brings, generally need set up the drainage well in the foundation slab, with groundwater level down to the design water level, ensure the stability of foundation ditch. The dewatering well is unavoidable in many underground excavation engineering, surface mining engineering and other activities, and meets the conditions of engineering construction requirements under the constraint of the water level dewatering requirement at a given point. And plugging the drainage well after precipitation is completed. However, the following two problems may occur in the process of plugging the drainage well: 1. the underground water pressure of the deep foundation pit in the region rich in underground water is high, and the plugging construction difficulty is high; 2. after the dry well is plugged, the water leakage phenomenon is easy to occur due to the overlarge pressure of underground water.
Disclosure of Invention
The invention aims to provide a method for plugging a drainage well in a water-carrying operation environment, which aims to solve the technical problems that the plugging construction difficulty is high when the underground water pressure of a deep foundation pit of a land with abundant underground water is high in the traditional plugging method, and the water leakage phenomenon is easy to occur due to the fact that the underground water pressure is too high after the drainage well is plugged.
In order to achieve the above purpose, the present invention adopts the following technical scheme.
A method for plugging a drain well in a water-carrying operation environment comprises the steps of plugging a wellhead of the drain well by adopting a drain well plugging device; the upper end of the drainage well is level with the top surface of the surrounding soil body; the drain well plugging device comprises a well pipe, a drain steel pipe, expanded concrete and a well cover; the well pipe is inserted into the upper part of the drain well, and the upper end of the well pipe exceeds the upper end of the drain well; a sealing ring is arranged in a joint between the well pipe and the drainage well; an annular water stop is arranged on the outer wall of the well pipe and at the port of the dredging well; a concrete cushion layer and a concrete bottom plate are sequentially arranged on the top of the soil body and around the well pipe from bottom to top; the top surface of the concrete bottom plate does not exceed the upper end of the well pipe; a plugging plate is arranged in the well pipe and close to the upper port; a round hole is formed in the middle of the plate surface of the plugging plate; the drainage steel pipe is inserted into the drain well, and the upper end of the drainage steel pipe passes through the round hole of the plugging plate; an upper opening section of the drain pipe is arranged above the drain steel pipe, and the upper end of the upper opening section of the drain pipe is positioned in the well pipe; a top cover is hinged at the upper port of the upper port section of the drain pipe; a butterfly valve is connected between the drainage steel pipe and the upper port section of the drainage pipe; the expansion concrete is poured into the well pipe above the plugging plate, and the top of the well pipe is sealed with a well cover; the well cover is welded with the well pipe.
The plugging method comprises the following steps.
Step one, welding a plugging plate at a position close to an upper port in a well pipe, wherein a round hole is formed in the middle of the plugging plate; and simultaneously, the water above the plugging plate is pumped out by adopting a water pumping device.
And step two, inserting the lower end of the well pipe into the drainage well, and filling a sealing ring in a gap between the well pipe and the drainage well.
And thirdly, welding an annular water stop on the outer wall of the well pipe and at the port of the drain well.
And step four, inserting the drainage steel pipe into the well pipe from the round hole of the plugging plate, enabling the lower end of the drainage steel pipe to extend into the drainage well, and enabling the upper end of the drainage steel pipe to be located in the well pipe above the plugging plate.
And fifthly, installing a butterfly valve at the upper end of the drainage steel pipe.
Step six, installing an upper port section of the drain pipe with a top cover at the upper port of the butterfly valve, connecting the water pumping device with the upper port of the upper port section of the drain pipe, opening the butterfly valve to perform water pumping operation, closing the butterfly valve and withdrawing the water pumping device after the underground water level reaches the requirement.
And seventh, pouring the expansion concrete, and then welding a well cover on the top of the well pipe.
Step eight, sequentially constructing a concrete cushion layer and a concrete bottom plate on the top of the soil body and around the well pipe from bottom to top; and finishing the construction.
Preferably, in the first step, the pumping device comprises a self-priming pump and a pump pipe; one end of a pump pipe is connected with a self-priming pump, the other end of the pump pipe stretches into a well pipe, and water overflowing from the drainage steel pipe is pumped out by adopting a pumping device.
Preferably, the outer edge of the middle annular water stop in the step II exceeds the outer side surface of the drainage well, and the exceeding part is covered on soil around the drainage well.
Preferably, in the fourth step, the interval between the lower end of the drainage steel pipe and the plugging plate is not less than 2m.
Preferably, in the fifth step, external threads are arranged on the upper part of the outer side wall of the drainage steel pipe, and external threads are arranged on the lower part of the side wall of the upper opening section of the drainage pipe; the butterfly valve is in threaded connection with the drain pipe and the upper opening section of the drain pipe respectively.
Preferably, the plugging plate is arranged inside the well pipe, and the distance between the plugging plate and the upper port of the well pipe is 250 mm-350 mm.
Compared with the prior art, the invention has the following characteristics and beneficial effects.
1. The surface of the traditional dry well is not protected by a cover plate when dewatering operation is carried out, construction waste, construction slag and the like are easy to fall into the well, a water pump is easy to damage in water pumping operation, and sundries can be effectively prevented from falling into the well after the device is adopted.
2. The traditional dewatering construction of the dry well adopts the submersible pump to pump water, the pump body needs to be put into water, maintenance and repair of the water pump are not suitable, and sundries are easy to damage the pump body in water.
3. The deep foundation pit underground water pressure of the dredge dry well in the abundant section of groundwater is great, easily causes the grit to gush up when adopting the grit shutoff, and the shutoff construction degree of difficulty is big, and the shutoff need not to adopt the grit shutoff after adopting the device, and the water pump is convenient for draw water and can guarantee that lower part water pressure is not too high.
Drawings
The invention is described in further detail below with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of a method for plugging a drain well in a water-carrying operation environment.
Reference numerals: 1-well lid, 2-expanded concrete, 3-drain pipe upper opening section, 4-butterfly valve, 5-shutoff board, 6-drainage steel pipe, 7-well pipe, 8-dry well, 9-sealing ring, 10-annular water stop, 11-top cap, 12-soil body, 13-concrete cushion layer, 14-concrete bottom plate.
Detailed Description
As shown in fig. 1, in the method for plugging the dry well under the water-carrying operation environment, a well mouth of the dry well 8 is plugged by adopting a dry well plugging device; the upper end of the drainage well 8 is level with the top surface of the surrounding soil body 12; the method is characterized in that: the drain well plugging device comprises a well pipe 7, a drain steel pipe 6, expanded concrete 2 and a well cover 1; the well pipe 7 is inserted into the upper part of the drain well 8, and the upper end of the well pipe 7 exceeds the upper end of the drain well 8; a sealing ring 9 is arranged in the joint between the well pipe 7 and the drainage well 8; an annular water stop 10 is arranged on the outer wall of the well pipe 7 and at the upper port of the dredging well 8; a concrete cushion layer 13 and a concrete bottom plate 14 are sequentially arranged on the top of the soil body 12 and around the well pipe 7 from bottom to top; the top surface of the concrete floor 14 does not exceed the upper end of the well pipe 7; a plugging plate 5 is arranged in the well pipe 7 and close to the upper port; a round hole is formed in the middle of the board surface of the plugging board 5; the drainage steel pipe 6 is inserted into the drainage well 8, and the upper end of the drainage steel pipe 6 passes through the round hole of the plugging plate 5; a drain pipe upper opening section 3 is arranged above the drain pipe 6, and the upper end of the drain pipe upper opening section 3 is positioned in the well pipe 7; a top cover 11 is hinged at the upper port of the upper port section 3 of the drain pipe; a butterfly valve 4 is connected between the drain steel pipe 6 and the drain pipe upper port section 3; the expansion concrete 2 is poured into a well pipe 7 above the plugging plate 5, and the top of the well pipe 7 is sealed with a well cover 1; the well cover 1 is welded with the well pipe 7.
The plugging method comprises the following steps.
Firstly, welding a plugging plate 5 at a position close to an upper port inside a well pipe 7, wherein a round hole is formed in the middle of the plugging plate 5; and simultaneously, the water above the plugging plate 5 is pumped out by adopting a water pumping device.
Step two, the lower end of the well pipe 7 is inserted into the drain well 8, and a seal ring 9 is filled in the gap between the well pipe 7 and the drain well 8.
And thirdly, welding an annular water stop 10 on the outer wall of the well pipe 7 at the upper port of the dredging well 8.
And step four, inserting the drainage steel pipe 6 into the well pipe 7 from the round hole of the plugging plate 5, enabling the lower end of the drainage steel pipe 6 to extend into the drainage well 8, and enabling the upper end of the drainage steel pipe 6 to be positioned in the well pipe 7 above the plugging plate 5.
And fifthly, installing a butterfly valve 4 at the upper end of the drainage steel pipe 6.
Step six, installing the upper port section 3 of the drain pipe with the top cover 11 at the upper port of the butterfly valve 4, connecting the pumping device with the upper port of the upper port section 3 of the drain pipe, opening the butterfly valve 4 to perform pumping operation, closing the butterfly valve 4 and withdrawing the pumping device after the underground water level reaches the requirement.
Step seven, pouring the expanded concrete 2 to a wellhead, and then welding a well cover 1 on the top of a well pipe 7, wherein the thickness of the well cover 1 is not less than 5mm; the expanded concrete 2 is C40 expanded concrete.
Step eight, sequentially constructing a concrete cushion layer 13 and a concrete bottom plate 14 on the top of the soil body 12 and around the well pipe 7 from bottom to top; and finishing the construction.
In the first step, the pumping device comprises a self-priming pump and a pump pipe; one end of a pump pipe is connected with a self-priming pump, the other end of the pump pipe stretches into a well pipe 7, and water overflowed from a drainage steel pipe 6 is pumped out by a pumping device; in the sixth step, the diameter of the upper opening section 3 of the drain pipe is slightly larger than the diameter of the pump pipe, and the pump pipe is inserted into the upper opening section 3 of the drain pipe, so that the pump pipe is easy to maintain, and the pump pipe is protected from being damaged.
In this embodiment, the outer edge of the annular water stop 10 in the step II exceeds the outer side surface of the drainage well 8, and the exceeding part is covered on the soil body 12 around the drainage well 8, and the annular water stop 10 is made of steel plates.
In this embodiment, the interval between the lower end of the drain steel pipe 6 and the plugging plate 5 in the fourth step is not less than 2m.
In the embodiment, the upper part of the outer side wall of the water draining steel pipe 6 in the fifth step is provided with external threads, and the lower part of the side wall of the water draining pipe upper port section 3 is provided with external threads; the butterfly valve 4 is respectively in threaded connection with the drain steel pipe 6 and the drain pipe upper port section 3.
In this embodiment, the plugging plate 5 is disposed inside the well pipe 7, and the interval between the plugging plate 5 and the upper port of the well pipe 7 is 250 mm-350 mm.
In this embodiment, the plugging plate 5 is made of a 5-5 mm thick round steel plate; the well lid 1 is made of steel plates with the thickness of 5 mm.
In this embodiment, the diameter of the drain steel pipe 6 is 48mm, the wall thickness is 3mm, and the drain steel pipe 6 is welded with the plugging plate 5.
Claims (6)
1. A method for plugging a drain well in a water-carrying operation environment comprises the steps of plugging a wellhead of the drain well (8) by adopting a drain well plugging device; the upper end of the drainage well (8) is level with the top surface of the surrounding soil body (12); the method is characterized in that: the drain well plugging device comprises a well pipe (7), a drain steel pipe (6), expanded concrete (2) and a well cover (1); the well pipe (7) is inserted into the upper part of the drain well (8), and the upper end of the well pipe (7) exceeds the upper end of the drain well (8); a sealing ring (9) is arranged in the joint between the well pipe (7) and the drainage well (8); an annular water stop belt (10) is arranged on the outer wall of the well pipe (7) and positioned at the upper port of the drain well (8); a concrete cushion layer (13) and a concrete bottom plate (14) are sequentially arranged on the top of the soil body (12) and around the well pipe (7) from bottom to top; the top surface of the concrete bottom plate (14) does not exceed the upper end of the well pipe (7); a plugging plate (5) is arranged in the well pipe (7) and close to the upper port; a round hole is formed in the middle of the board surface of the plugging board (5); the drainage steel pipe (6) is inserted into the drainage well (8), and the upper end of the drainage steel pipe (6) passes through the round hole of the plugging plate (5); a drain pipe upper opening section (3) is arranged above the drain pipe (6), and the upper end of the drain pipe upper opening section (3) is positioned in the well pipe (7); a top cover (11) is hinged at the upper port of the upper opening section (3) of the drain pipe; a butterfly valve (4) is connected between the drain steel pipe (6) and the drain pipe upper opening section (3); the expansion concrete (2) is poured into a well pipe (7) above the plugging plate (5), and a well cover (1) is sealed at the top of the well pipe (7); the well cover (1) is welded with the well pipe (7);
the plugging method comprises the following steps:
firstly, welding a plugging plate (5) at a position close to an upper port inside a well pipe (7), wherein a round hole is formed in the middle of the plugging plate (5); simultaneously, a water pumping device is adopted to pump out water above the plugging plate (5);
step two, inserting the lower end of the well pipe (7) into the drain well (8), and filling a sealing ring (9) in a gap between the well pipe (7) and the drain well (8);
step three, an annular water stop (10) is welded on the outer wall of the well pipe (7) and positioned at the upper port of the dredging well (8);
step four, inserting a drainage steel pipe (6) into the well pipe (7) from the round hole of the plugging plate (5), enabling the lower end of the drainage steel pipe (6) to extend into the drainage well (8), and enabling the upper end of the drainage steel pipe (6) to be positioned in the well pipe (7) above the plugging plate (5);
fifthly, installing a butterfly valve (4) at the upper end of the drainage steel pipe (6);
step six, installing a drain pipe upper port section (3) with a top cover (11) at the upper port of the butterfly valve (4), connecting a water pumping device with the upper port of the drain pipe upper port section (3), opening the butterfly valve (4) to perform water pumping operation, closing the butterfly valve (4) and withdrawing the water pumping device after the underground water level reaches the requirement;
step seven, pouring the expansion concrete (2), and then welding a well cover (1) on the top of the well pipe (7);
step eight, sequentially constructing a concrete cushion layer (13) and a concrete bottom plate (14) on the top of the soil body (12) and around the well pipe (7) from bottom to top; and finishing the construction.
2. The method for plugging a dry well in a water-carrying operation environment according to claim 1, wherein the method comprises the following steps: in the first step, the pumping device comprises a self-priming pump and a pump pipe; one end of a pump pipe is connected with a self-priming pump, the other end of the pump pipe stretches into a well pipe (7), and water overflowing from the drainage steel pipe (6) is pumped out by adopting a pumping device.
3. The method for plugging a dry well in a water-carrying operation environment according to claim 1, wherein the method comprises the following steps: in the second step, the outer edge of the annular water stop belt (10) exceeds the outer side surface of the drainage well (8), and the exceeding part is covered on soil (12) around the drainage well (8).
4. The method for plugging a dry well in a water-carrying operation environment according to claim 1, wherein the method comprises the following steps: and step four, the interval between the lower end of the drainage steel pipe (6) and the plugging plate (5) is not less than 2m.
5. The method for plugging a dry well in a water-carrying operation environment according to claim 1, wherein the method comprises the following steps: in the fifth step, external threads are arranged on the upper part of the outer side wall of the drain pipe (6), and external threads are arranged on the lower part of the side wall of the drain pipe upper opening section (3); the butterfly valve (4) is respectively in threaded connection with the drainage steel pipe (6) and the upper opening section (3) of the drainage pipe.
6. The method for plugging a dry well in a water-carrying operation environment according to claim 1, wherein the method comprises the following steps: the plugging plate (5) is arranged inside the well pipe (7), and the distance between the plugging plate (5) and the upper port of the well pipe (7) is 250-350 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310808023.4A CN116537238A (en) | 2023-07-04 | 2023-07-04 | Plugging method for dry well under water-carrying operation environment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310808023.4A CN116537238A (en) | 2023-07-04 | 2023-07-04 | Plugging method for dry well under water-carrying operation environment |
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| Publication Number | Publication Date |
|---|---|
| CN116537238A true CN116537238A (en) | 2023-08-04 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202310808023.4A Pending CN116537238A (en) | 2023-07-04 | 2023-07-04 | Plugging method for dry well under water-carrying operation environment |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007100401A (en) * | 2005-10-05 | 2007-04-19 | Izumi Pump Seisakusho:Kk | Undergroundwater level lowering apparatus |
| CN102839691A (en) * | 2011-06-22 | 2012-12-26 | 南通海洲建设集团有限公司 | Quick sealing method and device for sandless cement pipe deep well dewatering wellhead |
| CN111501805A (en) * | 2020-04-15 | 2020-08-07 | 中国二十冶集团有限公司 | Foundation pit bottom plate reserved precipitation plugging device and application method thereof |
| CN212688990U (en) * | 2020-06-17 | 2021-03-12 | 中建八局第四建设有限公司 | Well plugging device for dewatering well |
| CN114703878A (en) * | 2022-05-07 | 2022-07-05 | 中建八局第二建设有限公司 | Plugging and draining device for dewatering well and construction method |
-
2023
- 2023-07-04 CN CN202310808023.4A patent/CN116537238A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007100401A (en) * | 2005-10-05 | 2007-04-19 | Izumi Pump Seisakusho:Kk | Undergroundwater level lowering apparatus |
| CN102839691A (en) * | 2011-06-22 | 2012-12-26 | 南通海洲建设集团有限公司 | Quick sealing method and device for sandless cement pipe deep well dewatering wellhead |
| CN111501805A (en) * | 2020-04-15 | 2020-08-07 | 中国二十冶集团有限公司 | Foundation pit bottom plate reserved precipitation plugging device and application method thereof |
| CN212688990U (en) * | 2020-06-17 | 2021-03-12 | 中建八局第四建设有限公司 | Well plugging device for dewatering well |
| CN114703878A (en) * | 2022-05-07 | 2022-07-05 | 中建八局第二建设有限公司 | Plugging and draining device for dewatering well and construction method |
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