A precipitation structure and construction method

Abstract

The application relates to the technical field of foundation pit dewatering, in particular to a dewatering structure and a construction method, which comprise a first pipe body, a second pipe body and a water pump, the first pipe body is vertically arranged in a foundation pit, the second pipe body is arranged in the first pipe body, a first convex ring is arranged on the outer edge of the upper end of the second pipe body, a sand filter tank is arranged in the middle of the second pipe body, an annular gap is arranged between the upper part of the sand filter tank and the inner wall of the second pipe body, a second filter layer is arranged on the upper side opening of the annular gap, the second filter layer is arranged in a downward inclination mode, the second pipe body below the sand filter tank is provided with a bottom plate, the water pump is arranged on the bottom plate, and the water pump is provided with a water conveying pipeline which is communicated with the outside of the foundation pit. According to the application, the water pump is isolated from the bottom of the foundation pit with large sand accumulation, so that the water pump is prevented from disturbing the bottom of the foundation pit and bringing a large amount of sand and stones when pumping water, when the water pump works, water enters from the second filter layer of the second pipe body, the second filter layer filters and discharges the sand and stones to the sand filter tank in an inclined mode, the water pump is protected, and a high water pumping and dewatering effect is maintained.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of foundation pit dewatering, in particular to a dewatering structure and a construction method. BACKGROUND

[0002] Foundation pit dewatering refers to dewatering work performed when the underground water level is higher than the excavation bottom surface during excavation of a foundation pit, so as to ensure that the foundation pit can be constructed under dry conditions and prevent side slope instability, foundation pit sand flow, pit bottom uplift, pit bottom piping and foundation bearing capacity reduction. Generally, water pumps are used for dewatering operation. However, the water pump is prone to sucking out a large amount of sand in the foundation pit during pumping, and the excessive sand can damage the water pump. SUMMARY

[0003] In order to prevent excessive sand and stone from entering the water pump during dewatering operation and reduce water pump loss, the application provides a dewatering structure and a construction method.

[0004] The application provides a dewatering structure and a construction method, which adopt the following technical scheme:

[0005] A dewatering structure comprises a first pipe body, a second pipe body and a water pump. The first pipe body is vertically arranged in a foundation pit. The second pipe body is arranged in the first pipe body. A first convex ring is arranged on the outer edge of the upper end of the second pipe body. The first convex ring is attached to the inner wall of the first pipe body. A sand filter tank is arranged in the middle of the second pipe body. A first filter layer is arranged on the bottom surface of the sand filter tank. The first filter layer is composed of filter cloth and a steel mesh framework arranged in a vertical stack. An annular gap is arranged between the upper part of the sand filter tank and the inner wall of the second pipe body. A second filter layer is arranged on the upper side of the annular gap. The second filter layer is arranged in a downward inclination. A bottom plate is arranged below the second pipe body of the sand filter tank. The water pump is arranged on the bottom plate. The water pump is provided with a water delivery pipeline in communication with the outside of the foundation pit.

[0006] By arranging the water pump in the second pipe body, the water pump is separated from the bottom part of the foundation pit with a large amount of sand, so as to prevent the water pump from disturbing the bottom part of the foundation pit and bringing out a large amount of sand and stone when pumping water. When the water pump is working, water enters the second pipe body from the second filter layer, and the sand and stone falls into the sand filter tank along the inclined second filter layer. The sand and stone is prevented from accumulating on the second filter layer, so that the second filter layer maintains a high water permeability for a long time. The water pump is protected, and a high water pumping and dewatering effect is maintained.

[0007] Optionally, the second tube contains a support, and the upper outer edge of the support has a second convex ring, which is stacked on the first convex ring. The lower part of the support has the sand filter tank, and the support between the second convex ring and the sand filter tank has an inclined second filter layer. The second convex ring has a second water permeable hole, and the first convex ring has a first water permeable hole that is misaligned with the second water permeable hole. The bottom surface of the second convex ring is magnetically connected to the top surface of the first convex ring. When the second convex ring covers the first convex ring, the first convex ring blocks the second water permeable hole, and the second convex ring blocks the first water permeable hole.

[0008] By adopting the above technical solution, the sand filter tank and the second filter layer are placed on the support, and the support is connected to the second pipe body. This not only makes the equipment easier to manufacture, but also makes the water pump easier to install. The setting of the first and second water permeable holes reduces the water resistance experienced by the second pipe body and the support when there is water in the pit, making installation easier. The magnetic connection between the second convex ring and the first convex ring ensures that the support does not deflect during operation, and the first and second water permeable holes remain closed.

[0009] Optionally, the second pipe body is provided with a plurality of third water-permeable holes, and a third pipe body is provided inside the second pipe body. A floating ring is provided on the upper part of the inner side of the third pipe body. When water is injected into the second pipe body, the third pipe body floats up under the action of the floating ring and blocks the third water-permeable holes. The first convex ring, the first pipe body, the second pipe body, and the bottom surface of the foundation pit enclose a second dewatering chamber, and the third water-permeable holes are connected to the second dewatering chamber.

[0010] By adopting the above technical solution, the third pipe body floats up and down under the control of the floating ring. When the water in the second pipe body is full, the third pipe body is located at the top and blocks the third permeable hole, reducing the disturbance of the water pump to the second dewatering chamber, i.e. the bottom of the foundation pit with a large amount of sand accumulation, which is conducive to the settlement of sand and gravel at the bottom of the foundation pit. After most of the water in the foundation pit is pumped out, the water level in the second pipe body drops, and the third pipe body drops to expose the third permeable hole. At this time, the relatively clear water in the upper part of the second dewatering chamber after settlement enters the second pipe body and is pumped away by the water pump. Through the pumping operation of the partitioned chamber, the sand content in the water during pumping is effectively reduced, and the water pump wear is reduced.

[0011] Optionally, a first limit switch is provided on the upper part of the inner wall of the second pipe, and a second limit switch is provided on the bottom plate of the second pipe. When the float ring rises and presses against the first limit switch, the water pump starts; when the float ring falls and presses against the second limit switch, the water pump shuts down.

[0012] By adopting the above technical solution, the water pump can automatically pump water and reduce water level after the foundation pit reaches a certain water depth, ensuring the timeliness of water level control in the foundation pit and avoiding the situation where water overflows due to untimely water reduction.

[0013] Optionally, the sand filter tank is equipped with the sand filter cylinder, the bottom of the sand filter cylinder is equipped with a third filter layer, a spare filter chamber is provided between the third filter layer and the first filter layer, the upper end of the sand filter cylinder is equipped with a first traction rope connected to the outside of the foundation pit, the bottom surface of the sand filter cylinder is equipped with a second traction rope, the bottom of the support is equipped with a first guide wheel, the side of the support is equipped with a second guide wheel, the second convex ring is equipped with a third guide wheel, the second traction rope passes through the bottom surface of the sand filter tank and is guided by the first guide wheel, the second guide wheel and the third guide wheel in sequence before being connected to the outside of the foundation pit.

[0014] By adopting the above technical solution, the improved sand filter can continuously send the accumulated sand out of the foundation pit, preventing sand overflow from the filter and accumulating in the second filter layer; at the same time, when the sand filter is removed from the foundation pit for sand cleaning, the sand falls into the spare filter chamber, so that the sand can still fall into the spare filter chamber, avoiding sand accumulation in the second filter layer, ensuring a low sand ratio for water intake and uninterrupted operation of the water pump, and improving the dewatering efficiency.

[0015] Optionally, the second convex ring is provided with a brushing device, the brushing device including an annular brush frame rotatably mounted on the second convex ring, the inner side of the annular brush frame being provided with a brush parallel to the second filter layer; the outer peripheral wall of the annular brush frame is provided with a gear ring, the third guide wheel is provided with a coaxial first helical gear, the second convex ring is provided with a column, the column is provided with a second helical gear and a first gear, the second helical gear meshes with the first helical gear, and the first gear meshes with the gear ring to drive the annular brush frame to rotate.

[0016] By adopting the above technical solution, while lifting the filter sand cylinder, the second traction rope drives the ring brush frame to rotate, removing the accumulated sand on the second filter layer, so that the second filter layer maintains a high water permeability, ensuring sufficient water supply from the water pump and stability of water pumping and precipitation.

[0017] Optionally, the bottom surface of the bracket is provided with a movable rope clamp, the movable rope clamp includes a hollow column, a sliding strip is provided inside the hollow column, a first through hole is provided in the middle of the sliding strip, a first spring and a water-absorbing expansion block are respectively provided between the two ends of the sliding strip and the hollow column; the hollow column is provided with a second through hole, and the second traction rope passes through the first through hole and the second through hole.

[0018] By adopting the above technical solution, when the water level inside the second pipe is low, the water-absorbing expansion block is in a contracted state. The first spring inside the movable rope clamp pushes the sliding strip, causing the first and second through holes to misalign, thus locking the second traction rope. At this time, pulling the second traction rope will cause the support and the second pipe connected to the support to move upward simultaneously, realizing the release of the equipment. When the water level inside the second pipe is high, the water-absorbing expansion block absorbs water and expands, pushing the sliding strip so that the first and second through holes are aligned, allowing the second traction rope to pass through the movable rope clamp without obstruction. At this time, pulling the second traction rope will only move the filter cylinder up and down, completing the sand cleaning operation.

[0019] Optionally, the first convex ring is provided with an arc-shaped groove, the two ends of the arc-shaped groove are respectively provided on the top surface of the first convex ring and the side surface of the first convex ring, the two ends of the arc-shaped groove are provided with sliders, a plurality of water-absorbing expansion balls are provided between the sliders, and an anti-detachment structure is provided between the sliders and the arc-shaped groove.

[0020] By adopting the above technical solution, when the second tube body is loosened into the first tube body, the water-absorbing and expanding ball in the arc groove absorbs water and expands. Under the pressure of the second convex ring of the cooperating support, the slider located on the side of the first convex ring is squeezed against the inner wall of the first tube body, which strengthens the movement resistance of the second tube body in the first tube body and improves the structural stability when the first traction rope and the second traction rope pull the filter sand cylinder.

[0021] Optionally, the first tube body is provided with an annular groove, the annular groove is filled with filter material, and the groove wall is provided with a plurality of fourth water-permeable holes.

[0022] By employing the aforementioned technical solution, to allow groundwater in the soil to flow into the foundation pit through the pores, permeable holes are typically installed in the first pipe. At this location, the suction force on the inner wall of the foundation pit increases. Over time, this localized pore wall is prone to erosion and gradual collapse, leading to accelerated sand and gravel runoff. Adding a filter screen, however, can easily cause clogging, affecting the water inflow and reducing dewatering efficiency. This application uses an annular groove filled with filter media as an isolation support, which not only increases the permeable area of ​​the inner wall of the foundation pit on the outer wall of the first pipe, increasing the water inflow, but also provides some support to the inner wall of the foundation pit.

[0023] A construction method for a precipitation structure as described above includes the following steps:

[0024] S1, the third pipe body equipped with a float ring and the water pump are installed into the second pipe body;

[0025] S3, set up the first pipe body in the foundation pit, and use the first long rod to send the second pipe body prepared in step 1 into the first pipe body, so that the bottom plate of the second pipe body falls on the bottom surface of the foundation pit.

[0026] S3, the second long rod is used to send the support with the sand filter cylinder into the second tube, so that the second convex ring of the support overlaps with the first convex ring of the second tube;

[0027] S4, power on the water pump, the water pump runs from the inclined second filter layer on the support into the second pipe body and is pumped out of the pit by the water pump, and the sand and gravel slide from the second filter layer into the sand filter cylinder.

[0028] S5, the filter cylinder is pulled out by a first traction rope to remove the mud and sand in the filter cylinder, and then a second traction rope is pulled to pull the filter cylinder back into the support.

[0029] By adopting the above technical solution, the inclined second filter layer continuously plays a filtering role, filtering out sand and gravel in the water, keeping the water pump intake at a low sand ratio, reducing water pump wear, and at the same time, the sand and gravel are discharged in time through the sand filter cylinder, so that the precipitation operation can be carried out continuously and efficiently, improving precipitation efficiency.

[0030] In summary, this application includes at least one of the following beneficial technical effects: By setting a first pipe and a second pipe inside the foundation pit, the water pump inside the second pipe is isolated from the bottom of the foundation pit with a large amount of sand accumulation, preventing the water pump from disturbing the bottom of the foundation pit and carrying out a large amount of sand and gravel when pumping water. When the water pump is working, water enters from the second filter layer of the second pipe. The inclined second filter layer filters the sand and gravel and discharges it into the sand filter tank. The sand and gravel are not easy to accumulate in the second filter layer, so that the second filter layer maintains a high water permeability for a long time, thus protecting the water pump while maintaining a high pumping and dewatering effect. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of this application.

[0032] Figure 2 This is a top view of the structure of this application.

[0033] Figure 3 This is a schematic diagram of the annular groove structure of this application.

[0034] Figure 4 This is a schematic diagram of the arc-shaped groove structure of this application.

[0035] Figure 5 This is a schematic diagram of the rope clamp structure for this application.

[0036] Explanation of reference numerals in the attached drawings: 1. First pipe body; 11. Annular groove; 111. Filter media; 112. Fourth water permeable hole; 2. Second pipe body; 20. First convex ring; 200. First water permeable hole; 201. Arc-shaped groove; 202. Slider; 203. Water absorption expansion ball; 21. Third water permeable hole; 22. First limit switch; 23. Second limit switch; 24. Second rain chamber; 3. Water pump; 31. Water delivery pipe; 4. Support; 41. Second convex ring; 42. Second water permeable hole; 43. Third guide wheel; 44. First helical gear; 45. Column; 451. Second helical gear ; 452, First Gear; 46, First Guide Wheel; 47, Second Guide Wheel; 5, Movable Rope Clamp; 51, Hollow Column; 511, Second Through Hole; 52, Sliding Strip; 521, First Through Hole; 53, First Spring; 54, Water Absorption Expansion Block; 6, Sand Filter Tank; 61, Bottom Plate; 62, First Filter Layer; 63, Second Filter Layer; 7, Sand Filter Cylinder; 71, Third Filter Layer; 72, First Traction Rope; 73, Second Traction Rope; 8, Third Tube; 81, Floating Ring; 9, Sweeping Brush Device; 91, Ring Brush Frame; 92, Gear Ring; 93, Sweeping Brush; 10, Winch. Detailed Implementation

[0037] The following is in conjunction with the appendix Figures 1-5 This application will be described in further detail.

[0038] Reference Figures 1-3This application discloses a precipitation structure, including a first pipe body 1, a second pipe body 2, a support 4, and a water pump 3. The first pipe body 1 is vertically installed in a foundation pit and has an annular groove 11. The annular groove 11 is filled with filter material 111, such as coarse sand or gravel. The groove wall of the annular groove 11 has several fourth permeable holes 112. Specifically, the fourth permeable holes 112 can be mainly set on the lower groove wall and the inner groove wall of the annular groove 11. The annular groove 11 can be filled by setting an inlet on the upper wall of the annular groove 11 inside the pipe, or by covering it with a filter screen after filling. The second pipe body 2 is installed inside the first pipe body 1 and the support 4 is installed inside the second pipe body 2. The upper outer edge of the second pipe body 2 has a first convex ring 20, and the upper outer edge of the support 4 has a second convex ring 41, which is stacked on the first convex ring 20. The first convex ring 20 and the second convex ring 41 are attached to the inner wall of the first pipe body 1. The outer contours of the first convex ring 20 and the second convex ring 41 only need to largely conform to the inner wall of the first pipe body 1, leaving gaps such as those for a water supply pipe 31 to pass through. The second convex ring 41 has a second water-permeable hole 42, and the first convex ring 20 has a first water-permeable hole 200 that is offset from the second water-permeable hole 42. The bottom surface of the second convex ring 41 is magnetically connected to the top surface of the first convex ring 20. In this embodiment, a magnet is fixed to the bottom surface of the second convex ring 41, and the top surface of the first convex ring 20 is made of magnetic metal. When the second convex ring 41 covers the first convex ring 20, the first convex ring 20 blocks the second water-permeable hole 42, and the second convex ring 41 blocks the first water-permeable hole 200. (Refer to...) Figure 4 The first convex ring 20 is provided with an arc-shaped groove 201. The two ends of the arc-shaped groove 201 are respectively located on the top surface and the side surface of the first convex ring 20. A slider 202 is provided in the two ends of the arc-shaped groove 201. A plurality of water-absorbing and expanding balls 203 are provided between the sliders 202. An anti-detachment structure is provided between the sliders 202 and the arc-shaped groove 201. The anti-detachment structure includes a constriction at the end of the arc-shaped groove 201. One end of the slider 202 is narrow and the other end is wide. The narrow part can just enter and exit the constriction, and the wide part is just blocked by the constriction to prevent detachment. The water-absorbing and expanding balls 203 in the arc-shaped groove 201 absorb water and expand. Under the pressure of the second convex ring 41 of the cooperating bracket 4, the slider 202 located on the side of the first convex ring 20 is squeezed against the inner wall of the first tube 1, which increases the resistance to movement of the second tube 2 in the first tube 1.

[0039] Reference Figure 1The support frame 4 has a sand filter tank 6 at its lower part. The bottom surface of the sand filter tank 6 has a first filter layer 62, which is composed of filter cloth and steel mesh skeleton stacked on top of each other. There is an annular gap between the support frame 4 and the inner wall of the second pipe body 2. The second convex ring 41 with an opening on the upper side of the annular gap is provided on the support frame 4 between it and the sand filter tank 6, and an inclined second filter layer 63 is provided. The second filter layer 63 can be made of filter cloth. The second filter layer 63 is inclined downward and has a conical shape that is wider at the top and narrower at the bottom. The second pipe body 2 below the sand filter tank 6 has a base plate 61. The water pump 3 is located on the base plate 61. The water pump 3 has a water delivery pipe 31 that communicates with the outside of the foundation pit. The water delivery pipe 31 passes through the side wall of the second pipe body 2, the gap between the first convex ring 20 and the second convex ring 41 and the first pipe body 1, the clearance groove of the third pipe body 8 and the float ring 81, and then delivers water out of the foundation pit.

[0040] The second pipe body 2 is provided with several third permeable holes 21, and a third pipe body 8 is provided inside the second pipe body 2. A float ring 81 is provided on the upper part of the inner side of the third pipe body 8. When water is injected into the second pipe body 2, the third pipe body 8 floats up under the action of the float ring 81 and blocks the third permeable holes 21. The first convex ring 20, the first pipe body 1, the second pipe body 2, and the bottom surface of the foundation pit enclose and form a second dewatering chamber 24. The third permeable holes 21 are connected to the second dewatering chamber 24. A first limit switch 22 is provided on the upper part of the inner wall of the second pipe body 2, and a second limit switch 23 is provided on the bottom plate 61 of the second pipe body 2. When the float ring 81 rises and presses against the first limit switch 22, the first limit switch 22 sends information to the control terminal of the communication connection. The control terminal controls the water pump 3 to start according to the information fed back by the first limit switch 22. Similarly, when the float ring 81 descends and presses against the second limit switch 23, the control terminal controls the water pump 3 to shut down according to the information fed back by the second limit switch 23. At the same time, the first limit switch 22 can also prevent the float ring 81, i.e. the third tube 8, from rising and detaching from the second tube 2.

[0041] Reference Figure 1 The sand filter tank 6 contains a sand filter cylinder 7. A third filter layer 71 is located at the bottom of the sand filter cylinder 7. A spare filter chamber is located between the third filter layer 71 and the first filter layer 62. A first traction rope 72, connected to the outside of the foundation pit, is located at the upper end of the sand filter cylinder 7. The first traction rope 72 is connected to a winch 10. A second traction rope 73 is located on the bottom surface of the sand filter cylinder 7. Figure 5 The bottom surface of the bracket 4 is provided with a movable rope clamp 5. The movable rope clamp 5 includes a hollow column 51. A sliding strip 52 is provided inside the hollow column 51. A first through hole 521 is provided in the middle of the sliding strip 52. A first spring 53 and a water-absorbing expansion block 54 are respectively provided between the two ends of the sliding strip 52 and the hollow column 51. The hollow column 51 is provided with a second through hole 511. The second traction rope 73 passes through the first through hole 521 and the second through hole 511.

[0042] Reference Figure 1The support frame 4 has two first guide wheels 46 at its bottom, one near the movable rope catcher 5 and the other near the edge of the bottom surface of the support frame 4. A second guide wheel 47 is located on the side of the support frame 4, near the second filter layer 63. A third guide wheel 43 is located on the second convex ring 41. The support frame 4 has a wire hole and a wire groove for the second traction rope 73 to pass through, and the second tube 2 has a clearance groove for the second traction rope 73 to pass through. The second traction rope 73 passes through the bottom surface of the filter sand tank 6 and is guided sequentially by the first guide wheel 46, the second guide wheel 47, and the third guide wheel 43 before being connected to the winch 10 outside the pit.

[0043] Reference Figures 1-2 The second convex ring 41 is provided with a brushing device 9, which includes an annular brush holder 91 rotatably mounted on the second convex ring 41. The inner side of the annular brush holder 91 is provided with a brush 93 parallel to the second filter layer 63. There is a gap between the bristles of the brush 93 and the second filter layer 63, that is, the bristles of the brush 93 do not directly contact the second filter layer 63. The annular brush holder has a gear ring 92 on its outer peripheral wall. The third guide wheel 43 has a coaxial first helical gear 44. A column 45 is mounted on the second convex ring 41, and a second helical gear 451 and a first gear 452 are mounted on the column 45. The second helical gear 451 meshes with the first helical gear 44, and the first gear 452 meshes with the gear ring 92, driving the annular brush holder to rotate. Because the third guide wheel 43 and the second traction rope 73 slip underwater, the rotation of the annular brush holder may not be stable or uniform. In water with a typical sand and gravel content, the rotation and cleaning action of this annular brush holder is sufficient to meet the sand removal requirements of the second filter layer 63. In water with a high sand and gravel content, the friction between the third guide wheel 43 and the second traction rope 73 can be increased to increase the synchronous rotation rate of the third guide wheel 43, thereby improving the sand removal effect.

[0044] A construction method for a precipitation structure includes the following steps:

[0045] S1, the third pipe body 8 equipped with a float ring 81 and the water pump 3 are installed into the second pipe body 2.

[0046] S3, fill the annular groove 11 of the first tube 1 with filter material 111, then cover it with a filter screen, then place the first tube 1 in the foundation pit, and use a first long rod to connect with the top surface of the first convex ring 20 of the second tube 2 that was configured in step 1, and then send it into the first tube 1 so that the bottom plate 61 of the second tube 2 falls on the bottom surface of the foundation pit.

[0047] S3, place the bracket 4 on the first long rod. At this time, the first long rod passes through the second water-permeable hole 42 of the bracket 4. A second long rod is used to connect with the top surface of the second convex ring 41 of the bracket 4. The bracket 4 with the filter sand cylinder 7 is sent into the second tube 2, so that the second convex ring 41 of the bracket 4 and the first convex ring 20 of the second tube 2 magnetically overlap and mutually block the water-permeable hole.

[0048] S4, when the equipment is powered on, the float ring 81 inside the second pipe body 2 rises and presses against the first limit switch 22. The first limit switch 22 sends information to the control terminal of the communication connection. The control terminal controls the water pump 3 to start according to the information fed back by the first limit switch 22. Water flows from the inclined second filter layer 63 provided on the support 4 into the second pipe body 2 and is pumped out of the pit by the water pump 3. Sand and gravel slide from the second filter layer 63 into the sand filter cylinder 7, preventing the sand and gravel from accumulating in the second filter layer 63. This keeps the second filter layer 63 with a high water permeability for a long time, protecting the water pump 3 while maintaining a high pumping and dewatering effect.

[0049] S5, at regular intervals during pumping, the winch 10 is activated to pull the first traction rope 72 to remove the sand filter cylinder 7, clearing the silt from it. Then, the winch 10 is reversed to pull the second traction rope 73 back into the support 4. The sand filter cylinder 7 allows accumulated sand to be continuously discharged from the pit, preventing sand overflow and accumulation in the second filter layer 63. Simultaneously, when the sand filter cylinder 7 is removed from the pit for sand removal, the sand falls into the spare filter chamber, ensuring that sand can still accumulate in the spare filter chamber, preventing sand accumulation in the second filter layer 63, guaranteeing a low sand ratio in the water intake, and allowing the water pump 3 to operate continuously, thus improving dewatering efficiency.

[0050] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A precipitation structure, characterized in that: The system includes a first pipe body (1), a second pipe body (2), and a water pump (3). The first pipe body (1) is vertically installed in the foundation pit. The second pipe body (2) is installed inside the first pipe body (1). A first convex ring (20) is provided on the outer edge of the upper end of the second pipe body (2). The first convex ring (20) is attached to the inner wall of the first pipe body (1). A sand filter tank (6) is provided in the middle of the second pipe body (2). A first filter layer (62) is provided on the bottom surface of the sand filter tank (6). The first filter layer (62) is composed of filter cloth and steel mesh skeleton stacked on top of each other. A gap is provided between the upper part of the sand filter tank (6) and the inner wall of the second pipe body (2). There is an annular gap, and a second filter layer (63) is provided on the upper opening of the annular gap. The second filter layer (63) is inclined downward. The second pipe body (2) below the sand filter tank (6) is provided with a base plate (61). The water pump (3) is provided on the base plate (61). The water pump (3) is provided with a water delivery pipe (31) communicating with the outside of the foundation pit. A support (4) is provided inside the second pipe body (2). A second convex ring (41) is provided on the outer edge of the upper end of the support (4). The second convex ring (41) is stacked on the first convex ring (20). The sand filter tank (6) is provided at the lower part of the support (4). An inclined second filter layer (63) is provided on the support (4) between the second convex ring (41) and the filter sand tank (6); a second water permeable hole (42) is provided on the second convex ring (41), and a first water permeable hole (200) is provided on the first convex ring (20) which is misaligned with the second water permeable hole (42); the bottom surface of the second convex ring (41) is magnetically connected to the top surface of the first convex ring (20); when the second convex ring (41) covers the first convex ring (20), the first convex ring (20) blocks the second water permeable hole (42), and the second convex ring (41) blocks the first water permeable hole (200). Water permeable hole (200); the second pipe body (2) is provided with a number of third water permeable holes (21), and the second pipe body (2) is provided with a third pipe body (8) on the inner side. The upper part of the inner side of the third pipe body (8) is provided with a float ring (81). When water is injected into the second pipe body (2), the third pipe body (8) floats up under the action of the float ring (81) and blocks the third water permeable hole (21). The first convex ring (20), the first pipe body (1), the second pipe body (2), and the bottom surface of the foundation pit enclose and form a second precipitation chamber (24). The third water permeable hole (21) is connected to the second precipitation chamber (24).

2. The precipitation structure according to claim 1, characterized in that: The upper part of the inner wall of the second pipe body (2) is provided with a first limit switch (22), and the bottom plate (61) of the second pipe body (2) is provided with a second limit switch (23). When the float ring (81) rises and presses against the first limit switch (22), the water pump (3) starts; when the float ring (81) falls and presses against the second limit switch (23), the water pump (3) shuts down.

3. The precipitation structure according to claim 1, characterized in that: The sand filter tank (6) is equipped with a sand filter cylinder (7). The bottom of the sand filter cylinder (7) is equipped with a third filter layer (71). A spare filter chamber is provided between the third filter layer (71) and the first filter layer (62). The upper end of the sand filter cylinder (7) is equipped with a first traction rope (72) connected to the outside of the foundation pit. The bottom surface of the sand filter cylinder (7) is equipped with a second traction rope (73). The bottom of the support (4) is equipped with a first guide wheel (46). The side of the support (4) is equipped with a second guide wheel (47). The second convex ring (41) is equipped with a third guide wheel (43). The second traction rope (73) passes through the bottom surface of the sand filter tank (6) and is guided by the first guide wheel (46), the second guide wheel (47), and the third guide wheel (43) in sequence before being connected to the outside of the foundation pit.

4. The precipitation structure according to claim 3, characterized in that: The second convex ring (41) is provided with a brushing device (9), which includes an annular brush holder (91) rotatably mounted on the second convex ring (41). The inner side of the annular brush holder (91) is provided with a brush (93) parallel to the second filter layer (63). The outer peripheral wall of the annular brush holder is provided with a toothed ring (92). The third guide wheel (43) is provided with a coaxial first helical gear (44). The second convex ring (41) is provided with a column (45). The column (45) is provided with a second helical gear (451) and a first gear (452). The second helical gear (451) meshes with the first helical gear (44), and the first gear (452) meshes with the toothed ring (92) to drive the annular brush holder to rotate.

5. The precipitation structure according to claim 3, characterized in that: The bottom surface of the bracket (4) is provided with a movable rope clamp (5). The movable rope clamp (5) includes a hollow column (51). A sliding strip (52) is provided inside the hollow column (51). A first through hole (521) is provided in the middle of the sliding strip (52). A first spring (53) and a water-absorbing expansion block (54) are respectively provided between the two ends of the sliding strip (52) and the hollow column (51). A second through hole (511) is provided in the hollow column (51). The second traction rope (73) passes through the first through hole (521) and the second through hole (511).

6. The precipitation structure according to claim 1, characterized in that: The first convex ring (20) is provided with an arc-shaped groove (201). The two ends of the arc-shaped groove (201) are respectively located on the top surface of the first convex ring (20) and the side surface of the first convex ring (20). The two ends of the arc-shaped groove (201) are provided with sliders (202). A plurality of water-absorbing expansion balls (203) are provided between the sliders (202). An anti-detachment structure is provided between the sliders (202) and the arc-shaped groove (201).

7. The precipitation structure according to claim 1, characterized in that: The first tube (1) is provided with an annular groove (11), the annular groove (11) is filled with filter material (111), and the groove wall of the annular groove (11) is provided with a number of fourth water-permeable holes (112).

8. A construction method for a precipitation structure according to claim 3, characterized in that, Includes the following steps: S1, the third pipe body (8) equipped with a float ring (81) and the water pump (3) are installed into the second pipe body (2); S3, set up the first pipe body (1) in the foundation pit, and use the first long rod to send the second pipe body (2) prepared in step 1 into the first pipe body (1) so that the bottom plate (61) of the second pipe body (2) falls on the bottom surface of the foundation pit; S3, the bracket (4) with the filter cylinder (7) is inserted into the second tube (2) using the second long rod, so that the second convex ring (41) of the bracket (4) overlaps with the first convex ring (20) of the second tube (2); S4, power on the water pump (3), the water pump (3) runs and the water flows from the inclined second filter layer (63) provided on the support (4) into the second pipe body (2) and is pumped out of the pit by the water pump (3), and the sand and gravel slide from the second filter layer (63) into the sand filter cylinder (7); S5, the filter cylinder (7) is pulled out by a first traction rope (72) to remove the mud and sand in the filter cylinder (7), and then a second traction rope (73) is pulled to pull the filter cylinder (7) back into the bracket (4).

Images