Plugging method for dewatering well in foundation pit

Abstract

The invention discloses a plugging method for a dewatering well in a foundation pit, which belongs to the technical field of dewatering well plugging and comprises the following steps: S1, a filter pipe is hoisted into the dewatering well, and after gravel is filled into the inner side of the filter pipe, a steel plate is welded into the dewatering well; s2, water in the dewatering well is pumped out; s3, the water volume in the dewatering well is detected through a detection device; s4, a structural bottom plate is poured on the surface of the base layer; s5, a water outlet pipe penetrates through the steel plate and is inserted into the dewatering well, and slurry is injected into the dewatering well through the guide pipe till slurry flows out of the water outlet pipe; s6, the operation groove is filled with a filling material; when the steel plate is impacted by a large amount of water in the dewatering well, the annular plate is pressed to move upwards to trigger the warning device, so that the warning device gives an alarm to remind a worker, and therefore the worker can conduct adjustment in time according to the alarm, underground water is prevented from rushing out of the dewatering well, and meanwhile the impact force borne by the steel plate is reduced.

Description

Technical Field

[0001] This invention relates to the field of dewatering well sealing technology, specifically a method for sealing dewatering wells in foundation pits. Background Technology

[0002] In the sealing of dewatering wells in foundation pits, the dewatering wells are generally pumped out first, and then grouted and sealed. For example, the sealing method is disclosed in the publication document CN113789801B, which describes a sealing device and method for sealing dewatering wells in water-rich foundation pits. During the pumping process, a steel plate is first welded into the dewatering well, and then a pumping pipe is inserted deep into the dewatering well through the steel plate. A self-priming pump is used to pump the groundwater in the dewatering well out through the pumping pipe. However, due to the obstruction of the steel plate, the staff cannot see the situation below the steel plate. When the water flow in the dewatering well is large (the efficiency of the self-priming pump cannot keep up), the steel plate will be impacted, and the staff cannot detect the impact on the steel plate in time. Summary of the Invention

[0003] The purpose of this invention is to provide a method for sealing dewatering wells in foundation pits, in order to solve the problems mentioned in the background art, such as the inability of workers to see the situation below the steel plate due to the obstruction of the steel plate, and the inability to detect the impact of the steel plate when the water flow in the dewatering well is large.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for sealing dewatering wells in foundation pits, comprising the following steps:

[0005] S1: Lower the filter pipe into the dewatering well, fill the inside of the filter pipe with gravel, and then weld the steel plate into the dewatering well;

[0006] S2: After passing the self-priming pump's guide tube through the through hole in the steel plate and inserting it deep into the dewatering well, turn on the self-priming pump to pump out the water inside the dewatering well.

[0007] S3: Use a detection device to detect the water volume inside the dewatering well. If an impact is detected on the steel plate, a self-priming pump will be added. If no impact is detected on the steel plate, water will be pumped normally.

[0008] S4: Cast the structural base plate on the base surface and form an operating trough above the dewatering well;

[0009] S5: Pass the outlet pipe through the steel plate and insert it into the dewatering well. Inject grout into the dewatering well through the guide pipe until the grout comes out of the outlet pipe.

[0010] S6: Fill the operating tank with filler material;

[0011] The detection device includes an annular groove at the bottom of a steel plate, an annular plate that slides within the annular groove, and a warning device on the steel plate. When a large volume of water inside the dewatering well impacts the steel plate, the annular plate is pressed upwards, triggering the warning device to issue a warning.

[0012] Preferably, the steel plate is located above the filter tube.

[0013] Preferably, in step S6, before filling the operating groove with filler material, connecting steel bars are tied inside the operating groove.

[0014] Preferably, the warning device includes a mounting box installed on the top of a steel plate, a movable plate and a return spring connected to the movable plate are slidably disposed inside the mounting box, an indicator is provided on the top of the movable plate, an opening is provided on the top of the mounting box for the indicator to pass through, a connector is provided at the bottom of the movable plate, the bottom end of the connector extends into an annular groove and is connected to a balloon, the balloon is located above the annular plate, and a puncturing block for puncturing the balloon is provided in the annular groove.

[0015] Preferably, the warning device includes a mounting box installed on the top of a steel plate, a movable plate and a return spring connected to the movable plate are slidably disposed inside the mounting box, an indicator is provided on the top of the movable plate, an opening is provided on the top of the mounting box for the indicator to pass through, a screw is rotatably disposed on the bottom of the movable plate, the bottom end of the screw extends into an annular groove, and a threaded hole is provided at the connection between the steel plate and the screw.

[0016] Preferably, the indicator includes a support rod mounted on the top of the movable plate, a mounting sleeve rotatably sleeved on the outer wall of the support rod, a torsion spring between the mounting sleeve and the support rod, the top end of the mounting sleeve being inserted into an opening, the cross-section of the mounting sleeve and the opening being polygonal, conductive plates being provided on the inner wall of the mounting sleeve and the outer wall of the support rod, the two conductive plates being staggered and on the same moving path, and an alarm controlled by the two conductive plates being provided on the mounting sleeve.

[0017] Preferably, an elastic element is provided between the annular groove and the annular plate.

[0018] Preferably, the connection between the steel plate and the mounting box is provided with a slot, and the bottom of the mounting box is provided with a locking block for inserting into the slot.

[0019] Preferably, a limiting groove is provided on the inner side wall of the card slot, and an installation groove is provided on the side wall of the card block. A limiting block for insertion into the limiting groove and an elastic element connected to the limiting block are slidably provided in the installation groove. A pull rope is provided on the inner end of the limiting block, and the end of the pull rope extends to the outside of the mounting box.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: When the water volume inside the dewatering well is large and impacts the steel plate, the annular plate will move upward under pressure, triggering the warning device to issue a warning to alert the staff. This allows the staff to make timely adjustments based on the alarm, preventing groundwater from gushing out of the dewatering well and reducing the impact force on the steel plate, thus protecting the steel plate. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the dewatering well structure of the present invention;

[0022] Figure 2 This is an enlarged schematic diagram of the structure of the warning device at point A of the present invention;

[0023] Figure 3 This is an enlarged schematic diagram of the structure at point B in this invention;

[0024] Figure 4 This is an enlarged schematic diagram of another structure of the warning device at point A of the present invention;

[0025] Figure 5 This is an enlarged schematic diagram of the structure at point D in this invention;

[0026] Figure 6 This is an enlarged schematic diagram of the structure at point C in this invention;

[0027] Figure 7 This is a schematic diagram of the indicator structure of the present invention.

[0028] In the diagram: 1. Base layer; 2. Structural base plate; 3. Dewatering well; 4. Filter pipe; 5. Water-stop flange; 6. Steel plate; 7. Annular groove; 8. Annular plate; 9. Elastic element; 10. Mounting box; 11. Pull rope; 12. Conduit; 13. Water outlet pipe; 14. Indicator; 141. Support rod; 142. Mounting sleeve; 143. Torsion spring; 144. Conductive sheet; 145. Alarm; 15. Moving plate; 16. Balloon; 17. Puncture block; 18. Screw; 19. Locking block; 20. Locking groove; 21. Limiting block; 22. Limiting groove. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1

[0031] Please see Figure 1 A method for sealing dewatering wells in a foundation pit includes the following steps:

[0032] S1: Lower the filter pipe 4 into the dewatering well 3, fill the inside of the filter pipe 4 with gravel, and then weld the steel plate 6 into the dewatering well 3;

[0033] It should be noted that the outer wall of the filter pipe 4 abuts against the well wall of the dewatering well 3, and the lower end of the filter pipe 4 is inserted into the groundwater layer. The filter pipe 4 is filled with gravel. The filter pipe 4 allows water to pass through, while preventing the gravel from detaching from the dewatering well 3. The gravel acts as a filter layer, which is beneficial for drainage.

[0034] It should also be noted that the steel plate 6 is located above the filter tube 4.

[0035] S2: After passing the self-priming pump's guide tube 12 through the through hole of the steel plate 6 and inserting it deep into the dewatering well 3, turn on the self-priming pump to pump out the water inside the dewatering well 3.

[0036] It should be noted that the continuous pumping of the self-priming pump causes the groundwater level to drop, so that the grout can settle at the bottom of the dewatering well 3 during the subsequent grouting and sealing operation, which is beneficial for the overall sealing of the interior of the dewatering well 3; the through holes on the steel plate 6 were pre-drilled.

[0037] S3: Use a detection device to detect the water volume inside the dewatering well 3. If the steel plate 6 is detected to be impacted, a self-priming pump will be added. If the steel plate 6 is not detected to be impacted, water will be pumped normally.

[0038] It should be noted that when a large water flow is detected inside the dewatering well 3, causing an impact on the steel plate 6, the number of self-priming pumps is increased to accelerate the extraction of groundwater from the dewatering well 3, reduce the pressure on the steel plate 6, protect the steel plate 6, and prevent excessive pressure below the steel plate 6 from squeezing the conduit 12, thus avoiding affecting the pumping efficiency of the conduit 12; it also reduces the chance of groundwater gushing out from the dewatering well 3.

[0039] S4: Cast the structural base plate 2 on the surface of the base layer 1, and form an operating groove above the dewatering well 3;

[0040] It should be noted that the wellhead of the dewatering well 3 is higher than the surface of the base layer 1. A water-stop flange 5 is welded and fixed to the outer wall of the dewatering well 3. A structural base plate 2 is laid on the upper surface of the base layer 1. The water-stop flange 5 is embedded in the structural base plate 2. The water-stop flange 5 forms the first water-stop layer around the dewatering well 3, which is beneficial to improve the seepage around the dewatering well 3.

[0041] S5: Pass the outlet pipe 13 through the steel plate 6 and insert it into the dewatering well 3. Inject grout into the dewatering well 3 through the guide pipe 12 until the grout flows out of the outlet pipe 13.

[0042] It should be noted that before grouting, the self-priming pump's guide pipe 12 is pulled out from the through hole, and a valve is installed on the steel plate 6 to seal the through hole; then the grouting guide pipe 12 is inserted through the valve flange into the depth of the dewatering well 3; the outlet pipe 13 also passes through the valve flange.

[0043] S6: Fill the operating tank with filler material;

[0044] It should be noted that the filler material refers to non-shrink concrete. After the non-shrink concrete has solidified, the water outlet pipe 13 protruding from the surface of the filler material is cut off, thus completing the sealing construction of the dewatering well 3.

[0045] It should also be noted that before filling the operating groove with filler material in step S6, connecting steel bars are tied inside the operating groove.

[0046] Please see Figure 1 and Figure 2 The detection device includes an annular groove 7 at the bottom of the steel plate 6, an annular plate 8 slidingly disposed in the annular groove 7, the annular plate 8 being able to move up and down in the annular groove 7, and the gap between the side wall of the annular plate 8 and the inner side wall of the annular groove 7 being sealed (reducing the probability of water directly passing through the annular plate 8 and entering the interior of the annular groove 7); a warning device is provided on the steel plate 6.

[0047] In this embodiment, as a further optimization, please refer to... Figure 2 An elastic element 9 (such as a spring) is provided between the annular groove 7 and the annular plate 8; the elastic element 9 is used to support the annular plate 8 so that the annular plate 8 will not move easily and the warning device will not be easily triggered.

[0048] The working principle of the detection device is as follows: When the water volume inside the dewatering well 3 is large and impacts the steel plate 6, the annular plate 8 moves upward under pressure, triggering the warning device to issue an alarm. Based on the alarm, the staff can promptly understand the situation inside the dewatering well 3 and make timely adjustments (such as increasing the number of self-priming pumps or increasing the power of the self-priming pumps) to accelerate the discharge of groundwater inside the dewatering well 3, reduce the impact on the steel plate 6, and prevent groundwater from gushing out of the dewatering well 3.

[0049] In this embodiment, as a further optimization, the warning device has two configurations, as detailed below:

[0050] For the first option, please refer to [link / reference]. Figure 2 and Figure 3The warning device includes a mounting box 10 installed on top of a steel plate 6. A movable plate 15 is slidably mounted inside the mounting box 10 (the movable plate 15 can move up and down within the mounting box 10). A return spring is installed between the mounting box 10 and the movable plate 15. An indicator 14 is provided on the top of the movable plate 15. An opening is provided on the top of the mounting box 10, directly above the indicator 14. A connector (such as a rope) is provided at the bottom of the movable plate 15. The bottom end of the connector extends into an annular groove 7 and connects to a balloon 16. The balloon 16 is located above the annular plate 8. A puncture block 17 is provided at the top of the inner cavity of the annular groove 7. When the annular plate 8 is pressed upward, it squeezes the balloon 16, causing the balloon 16 to deform and come into contact with the puncture block 17. The puncture block 17 punctures the balloon 16, causing it to shrink and thus removing the restriction on the movable plate 15. Under the action of the return spring, the movable plate 15 moves upward with the indicator 14, exposing the indicator 14 to the outside of the mounting box 10, thus providing a warning effect.

[0051] The second option, please refer to Figure 4 and Figure 5 The warning device includes a mounting box 10 installed on top of the steel plate 6. A movable plate 15 is slidably mounted inside the mounting box 10 (the movable plate 15 can move up and down within the mounting box 10). A return spring is installed between the mounting box 10 and the movable plate 15. An indicator 14 is provided on the top of the movable plate 15. An opening is provided on the top of the mounting box 10, directly above the indicator 14. A screw 18 is rotatably mounted on the bottom of the movable plate 15, with its bottom end extending into the annular groove 7. A threaded hole is provided at the connection between the steel plate 6 and the screw 18. When the annular plate 8 is subjected to… When the screw is pressed upward, the annular plate 8 contacts the screw 18, applying an upward force to the screw 18, causing the screw 18 to rotate and move upward, moving out of the threaded hole (the thread pitch between the screw 18 and the threaded hole is relatively large, and the inclination angle is also large, so when an upward force is applied to the screw 18, the screw 18 will rotate and move upward), thus removing the restriction on the moving plate 15. Under the action of the return spring, the moving plate 15 moves upward with the indicator 14, exposing the indicator 14 to the outside of the mounting box 10, serving as a prompt.

[0052] In this embodiment, as a further optimization, please refer to... Figure 7The indicator 14 includes a support rod 141 mounted on the top of the movable plate 15. A mounting sleeve 142 is rotatably fitted onto the outer wall of the support rod 141. A torsion spring 143 is provided between the mounting sleeve 142 and the support rod 141. The top end of the mounting sleeve 142 is inserted into an opening (the outer wall of the mounting sleeve 142 is fully fitted with the inner wall of the opening). Both the mounting sleeve 142 and the opening have polygonal cross-sections (when the mounting sleeve 142 is still inserted into the opening, it cannot rotate on the outer wall of the support rod 141). Conductive plates 144 are provided inside the mounting sleeve 142 and on the outer wall of the support rod 141. Two conductive plates 144... The mounting sleeve 142 is misaligned and equipped with an alarm 145 (audible and visual alarm). The alarm 145 is connected to a power source and two conductive plates 144 via wires (the power source is a battery, which is installed on the mounting sleeve 142). As the moving plate 15 moves upward with the indicator 14, the mounting sleeve 142 moves to the outside of the mounting box 10 (the mounting sleeve 142 moves out of the opening). This removes the restriction of the opening on the mounting sleeve 142. Under the action of the torsion spring, the mounting sleeve 142 rotates, causing the two conductive plates 144 to come into contact, connecting the power source to the alarm 145 and causing it to sound an alarm.

[0053] Example 2

[0054] As a further optimization of Example 1, please refer to Figure 6 A slot 20 is provided at the connection between the steel plate 6 and the mounting box 10. A locking block 19 is provided at the bottom of the mounting box 10, and the locking block 19 is inserted into the inner cavity of the slot 20. A limiting groove 22 is provided on the inner side wall of the slot 20, and an installation groove is provided on the side wall of the locking block 19. A limiting block 21 is slidably provided in the installation groove. The end of the limiting block 21 away from the locking block 19 is inserted into the limiting groove 22. An elastic element (such as a spring) is installed between the installation groove and the limiting block 21. A pull rope 11 is provided on the side end, and the end of the pull rope 11 extends to the outside of the mounting box 10. After the water is pumped out, the operator pulls the pull rope 11 to move the limiting block 21 into the mounting groove and remove the limiting block 21 from the limiting groove 22. Then the operator continues to apply force to the pull rope 11 to remove the locking block 19 from the locking groove 20, thereby disconnecting the mounting box 10 from the steel plate 6 and removing the mounting box 10 from the steel plate 6 so that some components of the testing device can be reused.

[0055] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for sealing dewatering wells in a foundation pit, characterized in that: Includes the following steps: S1: The filter pipe (4) is lowered into the dewatering well (3), and gravel is filled into the inside of the filter pipe (4). Then the steel plate (6) is welded into the dewatering well (3). S2: After passing the self-priming pump pipe (12) through the through hole of the steel plate (6) and inserting it deep into the dewatering well (3), turn on the self-priming pump to pump out the water inside the dewatering well (3); S3: Use a detection device to detect the water volume inside the dewatering well (3). If the steel plate (6) is impacted, a self-priming pump is added. If the steel plate (6) is not impacted, water is pumped normally. S4: Cast the structural base plate (2) on the surface of the base layer (1) and form an operating groove above the dewatering well (3); S5: Pass the outlet pipe (13) through the steel plate (6) and insert it into the dewatering well (3). Inject grout into the dewatering well (3) through the conduit (12) until the grout flows out of the outlet pipe (13). S6: Fill the operating tank with filler material; The detection device includes an annular groove (7) at the bottom of the steel plate (6), an annular plate (8) is slidably disposed in the annular groove (7), and a warning device is provided on the steel plate (6); when the water volume inside the dewatering well (3) is large and impacts the steel plate (6), the annular plate (8) is pressed and moves upward to trigger the warning device, causing it to issue a warning.

2. The method for sealing dewatering wells in a foundation pit according to claim 1, characterized in that: The steel plate (6) is located above the filter tube (4).

3. The method for sealing dewatering wells in a foundation pit according to claim 1, characterized in that: Before filling the operating groove with filler material in step S6, connecting steel bars are tied inside the operating groove.

4. The method for sealing dewatering wells in a foundation pit according to claim 1, characterized in that: The warning device includes a mounting box (10) installed on the top of the steel plate (6). A movable plate (15) and a return spring connected to the movable plate (15) are slidably provided in the mounting box (10). An indicator (14) is provided on the top of the movable plate (15). An opening for the indicator (14) to pass through is provided on the top of the mounting box (10). A connector is provided at the bottom of the movable plate (15). The bottom end of the connector extends into the annular groove (7) and is connected to the balloon (16). The balloon (16) is above the annular plate (8). A puncturing block (17) for puncturing the balloon (16) is provided in the annular groove (7).

5. The method for sealing dewatering wells in a foundation pit according to claim 1, characterized in that: The warning device includes a mounting box (10) installed on the top of the steel plate (6). A movable plate (15) and a return spring connected to the movable plate (15) are slidably provided in the mounting box (10). An indicator (14) is provided on the top of the movable plate (15). An opening for the indicator (14) to pass through is provided on the top of the mounting box (10). A screw (18) is rotatably provided on the bottom of the movable plate (15). The bottom end of the screw (18) extends into the annular groove (7). A threaded hole is provided at the connection between the steel plate (6) and the screw (18).

6. A method for sealing dewatering wells in a foundation pit according to claim 4 or 5, characterized in that: The indicator (14) includes a support rod (141) mounted on the top of the movable plate (15). The outer wall of the support rod (141) is rotatably fitted with a mounting sleeve (142). A torsion spring (143) is provided between the mounting sleeve (142) and the support rod (141). The top end of the mounting sleeve (142) is inserted into an opening. The cross-section of the mounting sleeve (142) and the opening is polygonal. Conductive plates (144) are provided inside the mounting sleeve (142) and on the outer wall of the support rod (141). The two conductive plates (144) are staggered and on the same moving path. An alarm (145) controlled by the two conductive plates (144) is provided on the mounting sleeve (142).

7. The method for sealing dewatering wells in a foundation pit according to claim 1, characterized in that: An elastic element (9) is provided between the annular groove (7) and the annular plate (8).

8. A method for sealing dewatering wells in a foundation pit according to claim 4 or 5, characterized in that: The connection between the steel plate (6) and the mounting box (10) is provided with a slot (20), and the bottom of the mounting box (10) is provided with a card block (19) for inserting into the slot (20).

9. The method for sealing dewatering wells in a foundation pit according to claim 8, characterized in that: The inner wall of the slot (20) has a limiting groove (22), and the side wall of the block (19) has an installation groove. The installation groove has a limiting block (21) for insertion into the limiting groove (22) and an elastic element connected to the limiting block (21). The inner end of the limiting block (21) has a pull rope (11), and the end of the pull rope (11) extends to the outside of the mounting box (10).

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