Well sealing structure of precipitation well in water-rich sandy gravel stratum

Abstract

The utility model relates to a well sealing structure of a dewatering well in a water-rich sandy gravel stratum, which belongs to the technical field of well point dewatering and comprises a structural bottom plate and a dewatering well casing arranged in the structural bottom plate and extending downwards. The drainage pipe is installed in the dewatering well pipe, the bottom end of the drainage pipe is connected with a water suction pump, the top end of the drainage pipe extends out of the dewatering well pipe, a short steel pipe is installed at the top end of the drainage pipe, and a valve body is installed on the pipe wall of the short steel pipe; the steel sleeve is arranged in the structural bottom plate, the steel sleeve is in a state of being arranged on a pipe body at the top end of the drainage pipe in a sleeving mode, the steel sleeve is filled with a micro-expansion concrete body, and a sealing piece is installed at the top of the steel sleeve in a sealed mode; and the waterproof mortar layer is arranged in the structural bottom plate, and the top of the steel sleeve is located in the waterproof mortar layer. The well sealing structure not only is good in sealing effect, but also has good feasibility and economic benefits.

Description

Technical Field

[0001] The utility model relates to the technical field of well point dewatering, in particular to a well sealing structure for a dewatering well in a water-rich sand and pebble formation. Background Art

[0002] As the groundwater level rises, due to the rich water content of the water-rich sand and gravel strata and the high water head height, when the underground base is excavated to a certain depth, pressure relief wells should be set up to reduce the pressurized water and thus ensure the safety of the foundation pit.

[0003] When the groundwater level drops to 1-2m below the bottom of the foundation pit, and the deadweight of the reinforced concrete structure in the foundation pit is greater than the supporting force of the pressurized water, the pressure relief well can be closed. Due to the high water pressure in the pressure relief well, the underground gravel aquifer has a large permeability coefficient and abundant water inflow, so the sealing construction of the precipitation well is difficult. At present, the high-pressure grouting method is usually used for sealing, that is, the mixed mortar is injected into the precipitation well by the high-pressure grouting method. However, this method is costly and takes a long time, and the sealing failure phenomenon often occurs. Therefore, for foundation pits with abundant groundwater, there is an urgent need for a precipitation well sealing structure that is easy to operate, highly feasible, and has a good sealing effect. Utility Model Content

[0004] The utility model aims to provide a well sealing structure for a water-rich sand and gravel formation dewatering well, aiming at the problems of high cost, long construction period and poor sealing effect of the existing well sealing technology.

[0005] The utility model provides a well sealing structure for a water-rich sand and gravel formation dewatering well, which adopts the following technical solutions:

[0006] include,

[0007] A structural bottom plate, wherein a downwardly extending precipitation well pipe is arranged inside the structural bottom plate;

[0008] A drainage pipe is installed inside the precipitation well pipe, the bottom end of the drainage pipe is connected to a water pump, the top end of the drainage pipe extends out of the precipitation well pipe, a short steel pipe is installed at the top end of the drainage pipe, and a valve body is installed on the wall of the short steel pipe;

[0009] A steel casing is arranged inside the structural bottom plate, the steel casing is sleeved on the top pipe body of the drainage pipe, the inside of the steel casing is filled with a micro-expanding concrete body, and a sealing member is installed on the top of the steel casing;

[0010] A waterproof mortar layer is arranged inside the structural base plate, and the top of the steel casing is located inside the waterproof mortar layer.

[0011] Preferably, the space between the wall of the precipitation well pipe and the wall of the drainage pipe is sealed and filled with geotextile.

[0012] Preferably, a water-stop flange plate is installed on the pipe wall of the steel casing.

[0013] Preferably, the surface of the water-stop flange plate is coated with a first water-stop adhesive that is bonded to the wall of the steel casing.

[0014] Preferably, a cushion layer and a waterproof layer are sequentially arranged on the bottom of the structural base plate from bottom to top.

[0015] Preferably, the surface of the waterproof layer is coated with a second waterproof adhesive that is bonded to the wall of the steel casing.

[0016] Preferably, the sealing element comprises a steel pallet and a rubber sealing ring, wherein the rubber sealing ring is placed between the steel pallet and the top of the steel casing, and the steel pallet is sealingly connected to the top of the steel casing by bolts.

[0017] In summary, the utility model includes the following beneficial technical effects:

[0018] 1. The well sealing structure in the present application is aimed at precipitation wells with large water output. The water pump is abandoned in the water sealing well. The well sealing structure includes a valve body, a slightly expanding concrete body, a seal and a waterproof mortar layer. The valve body can change the opening and closing state of the drainage pipe. The slightly expanding concrete body of the steel casing seals the steel casing. The seal is arranged on the top of the steel casing. The seal further seals the steel casing. The waterproof mortar layer seals the steel casing. The valve body, the slightly expanding concrete body, the seal and the waterproof mortar layer seal the precipitation well four times, which improves the quality of the well sealing construction. The process is simple and easy to construct.

[0019] 2. By installing geotextiles on the walls of the precipitation well pipe and the drainage pipe, the geotextiles seal the precipitation well pipe, so that the micro-expansive concrete can be better retained and solidified in the steel casing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The utility model is a schematic structural diagram of a well sealing structure for a water-rich sand and gravel formation dewatering well provided by an embodiment of the utility model.

[0021] Explanation of the reference numerals in the accompanying drawings: 1. Structural base plate; 11. Cushion layer; 12. Waterproof layer; 121. Second water-stopping adhesive; 2. Dewatering well pipe; 3. Drain pipe; 31. Water pump; 32. Short steel pipe; 33. Valve body; 4. Steel casing; 41. Water-stopping flange plate; 42. First water-stopping adhesive; 5. Micro-expanding concrete body; 6. Seal; 61. Steel pallet; 62. Rubber sealing ring; 7. Waterproof mortar layer; 8. Geotextile. DETAILED DESCRIPTION

[0022] The following is combined with Figure 1 The utility model is described in further detail.

[0023] The utility model embodiment discloses a well sealing structure for a water-rich sand and gravel formation precipitation well. Referring to the figure, it includes a structural bottom plate 1, a precipitation well pipe 2 extending vertically downward is arranged inside the structural bottom plate 1, a drainage pipe 3 is installed inside the precipitation well pipe 2, a water pump 31 is connected to the bottom end of the drainage pipe 3, the top end of the drainage pipe 3 extends to the top of the precipitation well pipe 2, and a short steel pipe 32 is installed on the pipe body of the drainage pipe 3 located above the precipitation well pipe 2. The drainage pipe 3 in this embodiment is made of plastic material, and the short steel pipe 32 and the drainage pipe 3 are connected to one body by hot-melt welding. A valve body 33 is installed on the wall of the short steel pipe 32. The valve body 33 in this embodiment is preferably a ball valve; for precipitation wells with large water output, the valve body 33 is opened so that the water pump 31 can continue to work.

[0024] Reference Figure 1 The wall of the precipitation well pipe 2 and the wall of the drainage pipe 3 are sealed with a geotextile 8, which seals the precipitation well pipe 2. A steel casing 4 is sleeved on the top of the drainage pipe 3, and a water-stop flange plate 41 is welded to the wall of the steel casing 4. When producing and processing the steel casing 4, the water-stop flange plate 41 is welded to the wall of the steel casing 4 in advance, and the surface of the water-stop flange plate 41 is coated with a first water-stop glue 42 bonded to the wall of the steel casing 4, thereby enhancing the sealing between the water-stop flange plate 41 and the wall of the steel casing 4, and then the steel casing 4 is buried.

[0025] Reference Figure 1 The structural bottom plate 1 is sequentially constructed with a cushion layer 11 and a waterproof layer 12 from bottom to top, and the surface of the waterproof layer 12 is coated with a second waterproof glue 121 bonded to the wall of the steel casing 4, thereby enhancing the sealing between the waterproof layer 12 and the steel casing.

[0026] Reference Figure 1 After the water pump 31 is turned off, a slightly expanded concrete body 5 is filled inside the steel casing 4 to seal the inside of the steel casing 4, and a seal 6 is installed on the top of the steel casing 4 to seal the steel casing 4; the seal 6 includes a steel palpable plate 61 and a rubber sealing ring 62, and the rubber sealing ring 62 is placed between the steel palpable plate 61 and the top of the steel casing 4, and the steel palpable plate 61 is sealed and connected to the top of the steel casing 4 by bolts; a waterproof mortar layer 7 is poured at the position where the structural bottom plate 1 is located at the top of the steel casing 4, and the waterproof mortar layer 7 is vibrated and compacted. After the construction of the waterproof mortar layer 7 is completed, the top of the steel casing 4 is located inside the waterproof mortar layer 7, and the waterproof mortar layer 7 is cured for 28 days, thereby completing the sealing treatment of the steel casing 4.

[0027] The implementation principle of the sealing structure of a water-rich sand and gravel formation dewatering well in the utility model embodiment is as follows:

[0028] The present application adopts the method of abandoning the pump to seal the well, by installing the drainage pipe 3 in the precipitation well pipe 2, connecting the bottom end of the drainage pipe 3 to the water pump 31, connecting the top end of the drainage pipe 3 to the short steel pipe 32 with the valve body 33, and welding the water stop flange 41 to the side wall of the steel casing 4 in advance, and sleeve the steel casing 4 on the top end of the drainage pipe 3, so as to complete the burying of the steel casing 4; after the construction of the cushion layer 11 and the waterproof layer 12 is completed, the water pump 31 is turned off, and the valve body 33 is closed to prevent groundwater from gushing out of the drainage pipe 3, and the geotextile 8 is sealed and filled between the drainage pipe 3 and the precipitation well pipe 2, and a micro-expansion concrete body 5 is poured into the steel casing 4, and then the rubber sealing ring 62 and the steel pallet 61 are sealed and installed on the top of the steel casing 4, and the waterproof mortar layer 7 is poured on the position of the structural bottom plate 1 at the top end of the steel casing 4, so that the top of the steel casing 4 is located inside the waterproof mortar layer 7;

[0029] The precipitation well is sealed four times by means of the valve body 33, the micro-expanding concrete body 5, the sealing element 6 and the waterproof mortar layer 7, thereby improving the sealing effect. The construction is easy to operate, has strong feasibility and good economic benefits.

[0030] The above are all preferred embodiments of the present utility model, and are not intended to limit the protection scope of the present utility model. Therefore, any equivalent changes made based on the structure, shape, and principle of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A well sealing structure for a water-rich sand and gravel formation dewatering well. It is characterized in that include, A structural bottom plate (1), wherein a downwardly extending drainage well pipe (2) is arranged inside the structural bottom plate (1); A drainage pipe (3) is installed inside the drainage well pipe (2); the bottom end of the drainage pipe (3) is connected to a water pump (31); the top end of the drainage pipe (3) extends out of the drainage well pipe (2); a short steel pipe (32) is installed at the top end of the drainage pipe (3); a valve body (33) is installed on the wall of the short steel pipe (32); A steel casing (4) is arranged inside the structural bottom plate (1), the steel casing (4) is sleeved on the top end of the drainage pipe (3), the steel casing (4) is filled with a micro-expanding concrete body (5), and a sealing member (6) is installed at the top of the steel casing (4); A waterproof mortar layer (7) is arranged inside the structural base plate (1), and the top of the steel casing (4) is located inside the waterproof mortar layer (7).

2. A well sealing structure for dewatering wells in water-rich sand and gravel formations according to claim 1, It is characterized in that The space between the pipe wall of the precipitation well pipe (2) and the pipe wall of the drainage pipe (3) is sealed and filled with a geotextile (8).

3. A well sealing structure for dewatering wells in water-rich sand and gravel formations according to claim 1, It is characterized in that The pipe wall of the steel casing (4) is provided with a water-stop flange plate (41).

4. A well sealing structure for dewatering wells in water-rich sand and gravel formations according to claim 3, It is characterized in that The surface of the water-stop flange plate (41) is coated with a first water-stop adhesive (42) which is bonded to the wall of the steel casing (4).

5. A well sealing structure for dewatering wells in water-rich sand and gravel formations according to claim 1, It is characterized in that The bottom of the structural base plate (1) is provided with a cushion layer (11) and a waterproof layer (12) in sequence from bottom to top.

6. A well sealing structure for dewatering wells in water-rich sand and gravel formations according to claim 5, It is characterized in that The surface of the waterproof layer (12) is coated with a second waterproof adhesive (121) that is bonded to the wall of the steel casing (4).

7. A well sealing structure for dewatering wells in water-rich sand and gravel formations according to claim 1, It is characterized in that The sealing member (6) comprises a steel palpable plate (61) and a rubber sealing ring (62), wherein the rubber sealing ring (62) is placed between the steel palpable plate (61) and the top of the steel casing (4), and the steel palpable plate (61) is sealed and connected to the top of the steel casing (4) via bolts.

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