Foundation pit dewatering and drainage structure and construction method thereof

Abstract

The invention relates to the field of foundation pit dewatering and drainage, in particular to a foundation pit dewatering and drainage structure and a construction method thereof.The dewatering and drainage system comprises a dewatering module and a recharge module, a precipitation tank is arranged between the dewatering module and the recharge module, and a filtering tank and a collecting tank are further arranged between the precipitation tank and the dewatering module; a notch of the filter tank is provided with a rotary first filter plate, one end, close to the precipitation tank, of the first filter plate is a water filtering end, one end, close to the collecting tank, of the first filter plate is a sand discharging end, and the water filtering end of the first filter plate is provided with a baffle for filtering water; mounting seats are arranged on the two sides of the first filter plate respectively, limiting pieces are embedded in the mounting seats in a sliding mode, abutting pieces used for abutting against the limiting pieces are arranged on the first filter plate, elastic pieces used for resetting the abutting pieces are arranged in the mounting seats, and floating blocks are arranged in the filter grooves. According to the scheme, the effect of controlling and reducing the silt content of the underground water used for recharging in the foundation pit dewatering process can be achieved, and the silt generated by filtering the underground water can be automatically cleared away.

Description

Technical Field

[0001] The present application relates to the technical field of foundation pit drainage, and in particular to a foundation pit drainage structure and a construction method thereof. Background Art

[0002] Foundation pit dewatering refers to the dewatering work done during foundation pit excavation to ensure that the foundation pit can be constructed under dry conditions, prevent slope instability, foundation sand flow, pit bottom uplift, pit bottom pipe gushing and reduced foundation bearing capacity, as the groundwater level is higher than the excavation bottom, causing groundwater to continuously seep into the pit.

[0003] Common drainage methods used in engineering construction mainly include open ditch drainage and well point drainage. Open ditch drainage is an artificial drainage method, which refers to digging drainage ditches and water collection wells around the bottom of the foundation pit. A certain slope is set at the bottom of the ditch to lead water to the water collection well, and then use water pipes and water pumps to pump out the water in the water collection well. It is mainly used to remove underground groundwater, construction water and rainwater from the sky. Sometimes it is used as an auxiliary precipitation measure in combination with well point drainage. The main principle of well-point dewatering is to set up a certain number of well-point pipes on the ground around the foundation pit before excavation. The bottom of the well-point pipe is a water filter pipe that goes deep into the aquifer. The upper end of the well-point pipe is connected to the main water collection pipe. Pumping equipment is used to continuously extract groundwater from the well-point pipe to lower the original groundwater level to below the bottom of the pit to achieve the purpose of dewatering. It is often used in construction environments where the groundwater level is relatively high.

[0004] According to the different conditions and requirements of foundation pit excavation specifications, soil type, soil permeability coefficient and precipitation depth, appropriate precipitation methods are selected for construction. On the other hand, when there are adjacent buildings around the construction foundation pit, the drop in groundwater level will cause uneven settlement of adjacent buildings. The main practice at present is to use recharge well point technology, that is, set a row of recharge well pipes at a certain distance outside the precipitation well point setting line and insert them into the soil body, and inject the water drawn from the precipitation well point into the recharge well pipe after sedimentation, so as to reduce the groundwater level difference on the side of the foundation pit close to the adjacent building, thereby controlling the ground settlement, while the foundation pit can still remain dry.

[0005] The above-mentioned recharge method reduces the impact of foundation pit construction on the surrounding building environment while realizing the utilization of extracted groundwater, but it still has defects. Wellpoint dewatering should continuously extract groundwater. If the pumping equipment fails and causes intermittent pumping, the filter end of the wellpoint pipe is easily blocked, and the extracted groundwater has a large content of cement sand and is turbid. At this time, if recharge is carried out, it will block the recharge well pipe, and waiting for its sedimentation will take a long time. In addition, if the open ditch dewatering method is used, it is easy to bring out the soil particles generated by the construction in the foundation pit, and the turbidity of the extracted groundwater is even more uncontrollable, which will cause great difficulties for the overall construction of foundation pit dewatering, so it needs to be improved. Summary of the invention

[0006] In order to reduce the impact of extracting underground cement sand with a large content on the smooth progress of foundation pit dewatering construction, the present application provides a foundation pit dewatering structure and a construction method thereof.

[0007] In the first aspect, the present application provides a foundation pit drainage structure, which adopts the following technical solution: A foundation pit drainage structure includes a precipitation module and a recharging module, a sedimentation tank is arranged between the precipitation module and the recharging module, a filter tank and a collection tank are arranged between the sedimentation tank and the precipitation module, the filter tank is located between the collection tank and the precipitation tank, and the water outlet of the precipitation module is located above the filter tank; The notch of the filter tank is provided with a rotating first filter plate, one end of the first filter plate close to the sedimentation tank is a water filtering end, one end of the first filter plate close to the collection tank is a sand discharge end, the rotation axis of the first filter plate is horizontally arranged and close to the water filtering end, and the water filtering end of the first filter plate is provided with a baffle for filtering water; Mounting seats fixed to the notches of the filter tank are respectively provided on both sides of the first filter plate, the first filter plate is rotatably connected between the two mounting seats, a limit piece is slidably embedded on the mounting seat, an abutment piece for abutting and driving the limit piece to embed into the mounting seat is provided on the first filter plate, an elastic piece for driving the abutment piece to reset is provided in the mounting seat, and when the water filtering end of the first filter plate is lower than the sand discharging end, the limit piece is located on a path where the abutment piece follows the first filter plate to rotate toward the water filtering end and gradually becomes higher than the sand discharging end; a floating block for supporting the first filter plate is also provided in the filter tank.

[0008] By adopting the above technical solution, the state of the first filter plate is initially adjusted so that its water filtering end is higher than the sand discharging end. At the same time, the abutment is located on the side where the limiter restricts the sand discharging end of the first filter plate from rotating downward. A certain amount of water is injected into the filter tank, and the buoyancy provided by the floating block can drive the abutment to abut and pass over the limiter. The groundwater pumped out by the precipitation module falls on the first filter plate and is affected by gravity. After being filtered by the baffle, it flows into the sedimentation tank. The weight of the sediment accumulated on the first filter plate gradually increases, and the tendency of the sand discharge end of the first filter plate to rotate downward also increases. When the resistance provided by the limiter and the buoyancy provided by the float are insufficient to support, the abutment member passes over the limiter and is supported by the buoyancy of the float only. At this time, the accumulated gravity due to the action of the limiter allows the first filter plate to rotate faster, preventing the first filter plate from staying in a horizontal state for too long. The sand discharge end of the first filter plate rotates to the lowest position. At this time, the water discharged by the precipitation module flushes the sediment into the collection tank, and the weight on the first filter plate is reduced. The first filter plate is then driven back to its original position by the support of the float to realize a reciprocating cycle.

[0009] Through the setting of this scheme, firstly, the groundwater extracted by the precipitation module is first filtered by the first filter plate and then discharged into the sedimentation tank, which can reduce the impact of changes in the turbidity of the extracted groundwater on the water in the sedimentation tank. The sediment content of the water in the sedimentation tank is more stable, and the reinjection module can smoothly reinject groundwater; secondly, in order to filter the groundwater without increasing the workload of construction personnel to clean up the sediment, the sediment accumulated on the first filter plate can be automatically cleaned, and the scheme has a simple structure, does not rely on electrical equipment, and faces the harsh environment of the construction site, has a lower probability of failure, and has higher practicality.

[0010] Preferably, a first filter hole is provided on the first filter plate, and a partition is slidably fitted on the bottom surface of the first filter plate, the sliding direction of the partition is perpendicular to the rotation axis direction of the first filter plate, and the partition is used to close the first filter hole of the first filter plate when the water filtering end of the first filter plate is lower than the sand discharging end.

[0011] By adopting the above technical solution, the partition closes the first filter hole so that the water on the first filter plate can only flow into the sedimentation tank through the baffle. When the first filter plate rotates so that the water filtering end is higher than the sand discharge end, the partition slides under the action of gravity and avoids the first filter hole. Part of the water on the first filter plate is mixed with the sediment and falls into the collection tank, and part of it is filtered through the first filter hole and falls into the filter tank, thereby replenishing the water in the filter tank. Whether the sand discharge end of the first filter plate can be reset by rotating upward depends on whether the buoyancy provided by the float is sufficient. When the water in the water filtration process is used to replenish the filter tank, it can avoid the impact of the drop in the liquid level in the filter tank due to natural evaporation or other factors on the normal operation of the device, thereby eliminating excessive manual intervention. Secondly, there is no need to calculate the amount of water injected into the filter tank too accurately. After a part of the mud and sand accumulated on the first filter plate is washed away, the water replenished into the filter tank through the first filter plate gradually increases, which can ensure that the first filter plate is smoothly rotated back to its original position, thereby improving the rationality and practicality of this solution.

[0012] Preferably, the filter tank is provided with a drainage hole connected to the sedimentation tank, and the position of the drainage hole is higher than the notch of the sedimentation tank.

[0013] By adopting the above technical scheme, when the liquid level in the filter tank exceeds the drainage hole, part of the filtered water in the filter tank can be discharged from the drainage hole into the sedimentation tank, so as to avoid excessive water in the filter tank causing excessive resistance when the sand discharge end of the first filter plate rotates downward. The rotation cycle of the first filter plate can be smoother, and the mud and sand accumulated on the first filter plate can be flushed into the collection tank in time without accumulating too much. In addition, the position of the drainage hole is higher than the notch of the sedimentation tank, and the water in the sedimentation tank cannot flow into the filter tank.

[0014] Preferably, the drainage hole is provided with a sealing member, and a push rod for pushing the sealing member is provided on the first filter plate; when the first filter plate rotates so that the water filtering end is gradually lower than the sand discharging end, and the abutment member can abut against the limiting member to complete a reciprocating sliding, the push rod opens the drainage hole by pushing the sealing member.

[0015] By adopting the above technical solution, the position of the drain hole determines the upper limit of the liquid level in the filter tank, and the active opening and closing of the drain hole is realized by setting the push rod and the seal, and the position setting of the drain hole can be more flexible. The upper limit of the liquid level in the filter tank can be set by setting the position height of the drain hole, so that when the water filtering end of the first filter plate is higher than the sand discharge end, the first filter plate is supported only by the limiter, so that less sediment can be accumulated on the first filter plate to achieve rotation. When the height of the two ends of the first filter plate is swapped, water is added to the filter tank until the first filter plate is reversed. At this time, the push rod pushes the seal to open the drain hole, and the liquid level of the water in the filter tank is lowered to the position of the drain hole. This cycle is repeated, further increasing the practicality and flexibility of the overall structure.

[0016] Preferably, when the water filtering end of the first filter plate is located higher than the sand discharging end, the abutment member can abut against the limiting member.

[0017] By adopting the above technical solution, when the first filter plate is subjected to buoyancy and tends to rotate in the direction where the water filtering end is gradually lower than the sand discharging end, the buoyancy received by the first filter plate is greater than the resistance of the abutment limiter, and the abutment limiter can rotate along with the first filter plate to pass the limiter. In this way, the rotation of the first filter plate can be temporarily suspended, so that the first filter plate can accumulate some buoyancy. Before the partition closes the first filter hole of the first filter plate, the abutment limiter can smoothly pass the limiter, so that the problem of the buoyancy received by the first filter plate being insufficient to support the abutment limiter to pass the limiter when the partition closes the first filter hole does not occur.

[0018] Preferably, the water outlet of the precipitation module is located above the first filter plate on the side biased towards the water filtering end.

[0019] By adopting the above technical solution, the sediment is mainly gathered at the water filtering end of the first filter plate after being filtered by the baffle plate. The water outlet of the precipitation module is set close to the water filtering end of the first filter plate, so that more sediment can be washed away and the cleaning effect is improved. At the same time, the flow distance of water on the first filter plate can be extended, so that the water can fall into the filter tank through the first filter hole in time, thereby improving the efficiency of replenishing water to the filter tank.

[0020] Preferably, a second filter hole is provided on a side wall of the collecting tank close to the filtering tank, and the collecting tank is connected to the filtering tank through the second filter hole.

[0021] By adopting the above technical solution, the water flowing into the collection tank is filtered through the second filter hole and then flows into the filter tank, which can not only reduce the amount of water accumulation in the collection tank, but also speed up the speed of replenishing water to the filter tank, thereby enabling the first filter plate to rotate faster.

[0022] Preferably, the bottom of the collecting trough is open and suspended, and a flap for opening and closing the opening is provided at the bottom of the collecting trough.

[0023] By adopting the above technical solution, the flap can be opened to open the opening at the bottom of the collecting tank, and the mud and sand can fall from the collecting tank, making it convenient to clean it.

[0024] On the other hand, the present application also provides a construction method of a foundation pit drainage structure, which adopts the following technical solution: S1. Arrange and bury relevant pipelines of precipitation module and recharging module; S2. Set a sedimentation tank, a filter tank and a collection tank between the pipelines of the precipitation module and the recharging module; S3, installing a first filter plate and a floating block above the notch of the filter tank; S4. Pre-inject a proper amount of water into the filter tank to adjust the position height of the floating block, and support the first filter plate through the floating block so that the water filtering end of the first filter plate is gradually lower than the sand discharging end, and the abutment can drive the limiter to be embedded in the mounting seat.

[0025] By adopting the above technical solution, the extracted groundwater from the foundation pit is first filtered through the first filter plate before being discharged into the sedimentation tank, which can reduce the impact of changes in the turbidity of the extracted groundwater on changes in the sediment content of the water in the sedimentation tank, thereby reducing the probability of blockage problems in the recharge module pipeline. In addition, based on the arrangement that the first filter plate can rotate back and forth, the precipitation module is used to extract groundwater, which can automatically clean the sediment accumulated on the first filter plate, thereby reducing the intervention of on-site construction personnel in the operation of the device.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. By setting the first filter plate and the baffle plate, the extracted groundwater is filtered before being discharged into the sedimentation tank, which can reduce the impact of the change in the turbidity of the groundwater on the sediment content of the water in the sedimentation tank, and the recharge module can recharge the groundwater smoothly; 2. Through the rotation of the first filter plate and the setting of the floating block, combined with the principle of using groundwater extraction to provide buoyancy to support, the first filter plate can filter the sediment and automatically clean the sediment in a reciprocating cycle; 3. Through the setting of the collection tank, the filtered sediment can be collected centrally, which is convenient for cleaning and transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1It is a side view of the drainage system of the present application; Figure 2 It is a partial cross-sectional schematic diagram mainly showing the filtering module of the drainage system of the present application when the first filter plate is at the water filtering position; Figure 3 It is a schematic diagram mainly showing the relative position relationship between the abutment member and the limit member when the first filter plate is at the water filtering position; Figure 4 It is a partial cross-sectional schematic diagram mainly showing the filtering module of the drainage system of the present application when the first filter plate is in the sand discharge position; Figure 5 It is a schematic diagram mainly showing the relative position relationship between the abutment member and the limiting member when the first filter plate is in the sand discharge position.

[0028] Explanation of reference numerals: 1. foundation pit; 11. open ditch; 2. precipitation module; 21. water pipe; 22. well point pipe; 23. precipitation main pipe; 24. outlet pipe; 3. sedimentation tank; 4. recharging module; 41. recharging main pipe; 42. recharging well pipe; 5. filter module; 51. filter tank; 511. drainage hole; 512. sealing element; 52. first filter plate; 521. water filter end; 522. sand discharge end; 523, first filter hole; 524, slide groove; 53, baffle; 54, floating block; 541, connecting rod; 55, partition; 551, through groove; 56, abutment; 57, mounting seat; 571, limit member; 572, reset member; 58, push rod; 59, side plate; 6, collecting tank; 61, second filter plate; 611, second filter hole; 62, flap; 63, lock; 7, adjacent buildings. DETAILED DESCRIPTION

[0029] The following is combined with Figure 1-5 This application is described in further detail.

[0030] The present application embodiment discloses a foundation pit drainage structure. Figure 1 The foundation pit drainage structure includes a drainage module 2. In this embodiment, the drainage module 2 includes a row of multiple well point pipes 22 buried on one side of the foundation pit 1. The multiple well points are arranged at intervals along the extension direction of the side of the foundation pit 1 and are connected through a drainage main pipe 23. In other embodiments, well point pipes 22 can also be set on both sides or the surrounding side of the foundation pit 1. The well point pipe 22 is also connected to a water pipe 21 extending to the open ditch 12 at the bottom of the foundation pit 1, and the groundwater in the foundation pit 1 and the accumulated water in the open ditch 11 in the pit are pumped out through the pumping equipment.

[0031] Reference Figure 1A recharge module 4 is also provided between the precipitation module 2 and the adjacent building 7. The recharge module 4 includes a row of recharge well pipes 42 buried in the soil. The arrangement direction of the multiple recharge well pipes 42 is parallel to the arrangement direction of the well point pipes 22. The recharge well pipes 42 are connected through a recharge main pipe 41. A sedimentation tank 3 is also excavated on the ground outside the foundation pit 1 between the recharge module 4 and the precipitation module 2 to accommodate and precipitate the groundwater extracted by the precipitation module 2. The water intake of the recharge main pipe 41 extends into the bottom of the sedimentation tank 3 to extract the precipitated water and recharge the groundwater level of the adjacent building 7.

[0032] Reference Figure 1 and Figure 2 A filter module 5 is also arranged between the precipitation module 2 and the sedimentation tank 3. The filter module 5 includes a filter tank 51 with a rectangular notch. The length direction of the filter tank 51 is perpendicular to the horizontal arrangement direction of the precipitation module 2 and the recharging module 4. A long strip first filter plate 52 is rotatably arranged above the notch of the filter tank 51. The rotation axis of the first filter plate 52 is arranged horizontally, and the extension direction of the rotation axis is perpendicular to the length direction of the notch of the filter tank 51. The end of the first filter plate 52 close to the sedimentation tank 3 in the length direction is the water filtering end 521, and the end close to the collection tank 6 is the sand discharge end 522. The distance from the rotation axis of the first filter plate 52 to the water filtering end 521 is less than the distance from the first filter plate 52 to the sand discharge end 522. A long strip baffle 53 is arranged at the water filtering end 521 of the first filter plate 52. The length of the baffle 53 is the same as the width of the first filter plate 52. One side of the long side of the baffle 53 is fixedly connected to the first filter plate 52, and the other side is higher than the upper surface of the first filter plate 52. A side plate 59 is fixedly connected to each of the two long sides of the first filter plate 52 .

[0033] Reference Figure 1 and Figure 2 The precipitation main pipe 23 is connected to a water outlet pipe 2421, and the water outlet of the water outlet pipe 2421 is located above the filter plate, and the water filtering end 521 of the first filter plate 52 is also within the notch range of the sedimentation tank 3. When the water filtering end 521 of the first filter plate 52 is lower than the sand discharge end 522, the groundwater discharged by the water outlet pipe 2421 falls on the first filter plate 52. Under the action of gravity and the enclosure provided by the two side plates 59, the groundwater flows to the water filtering end 521 of the first filter plate 52. The baffle plate 53 is provided with filter holes. After being filtered by the baffle plate 53, the water falls into the sedimentation tank 3 for extraction by the recharge module 4, which can reduce the influence of the turbidity change of the extracted groundwater on the sediment content in the sediment.

[0034] Reference Figure 1 and Figure 2A collecting tank 6 is also provided between the filter tank 51 and the precipitation module 2, and the collecting tank 6 is mainly used to collect the sediment accumulated on the first filter plate 52. The sand discharge end 522 of the first filter plate 52 is within the notch range of the collecting tank 6. When the water filter end 521 of the first filter plate 52 is higher than the sand discharge end 522, the water discharged from the outlet pipe 2421 falls on the first filter plate 52 and can be flushed into the collecting tank 6 with the sediment under the action of gravity, so as to clean the sediment after filtration.

[0035] For the convenience of description in the following text of this embodiment, the water filtering end 521 of the first filter plate 52 is located lower than the sand discharging end 522, and when the first filter plate 52 is rotated to the limit angle that can be rotated in this direction, such as the bottom surface of the first filter plate 52 hits the notch of the filter tank 51 and stops rotating, the state of the first filter plate 52 at this time is referred to as the water filtering position; on the contrary, when the water filtering end 521 of the first filter plate 52 is located higher than the sand discharging end 522, and when the first filter plate 52 is rotated to the limit angle that can be rotated in this direction, such as the bottom surface of the first filter plate 52 hits the notch of the filter tank 51 and stops rotating, the state of the first filter plate 52 at this time is referred to as the sand discharging position. In this embodiment, the angle between the first filter plate 52 and the horizontal plane when it is in the water filtering position is the same as the angle between the first filter plate 52 and the horizontal plane when it is in the sand discharging position.

[0036] Reference Figure 2 A floating block 54 is disposed below the first filter plate 52 and is located in the filter tank 51. The floating block 54 and the first filter plate 52 are connected by a connecting rod 541. One end of the connecting rod 541 is fixedly connected to the first filter plate 52, and the other end is hinged to the floating block 54. After a proper amount of water is injected into the filter tank 51, the liquid level in the filter tank 51 rises and drives the first filter plate 52 to rotate through the floating block 54, so that the first filter plate 52 rotates from the sand discharge position to the water filtration position.

[0037] The weight of the first filter plate 52 and the sediment is balanced with the buoyancy provided by the float 54. When the first filter plate 52 is at the water filtering position and sediment gradually accumulates, the float 54 provides buoyancy by lowering its own position to discharge more water, and the first filter plate 52 gradually rotates from the water filtering position to the sediment discharge position. When the sediment on the first filter plate 52 is washed away, the buoyancy transmitted by the float 54 to the first filter plate 52 is greater than its own gravity, and the first filter plate 52 rotates from the sediment discharge position to the water filtering position to achieve circulation.

[0038] Reference Figure 2 and Figure 3Two mounting seats 57 are fixed to the notch of the filter tank 51. The two mounting seats 57 are respectively located on both sides of the first filter plate 52. The rotating shaft of the first filter plate 52 is rotatably connected between the two mounting seats 57. A stopper 571 is slidably embedded in one of the mounting seats 57. The end of the stopper 571 extending out of the mounting seat 57 is set as a round head. A reset member 572 is set in the mounting seat 57 to drive the stopper 571 to slide out of the mounting seat 57. The reset member 572 can be a spring or other elastic structure.

[0039] Reference Figure 2 and Figure 3 The first filter plate 52 is provided with an abutment member 56 for abutting against the limiting member 571. In this embodiment, the abutment member 56 is fixedly connected to one long side of the first filter plate 52 and is located on the same side of the first filter plate 52 as the mounting seat 57 provided with the limiting member 571. The abutment member 56 is provided as an arc-shaped plate with a certain curvature. The end of the limiting member 571 extending out of the mounting seat 57 is located on the path of the abutment member 56 following the rotation of the first filter plate 52. When the first filter plate 52 is at the water filtering position, the limiting member 571 abuts against the abutment member 56, and the limiting member 571 is located on the side of the abutment member 56 following the rotation direction of the first filter plate 52 toward the sand discharge position.

[0040] When the sediment accumulated on the first filter plate 52 reaches a certain weight, the abutment 56 overcomes the resistance generated by the deformation of the reset member 572 to drive the limit member 571 to fit into the mounting seat 57, and then the abutment 56 passes the position of the limit member 571, and then the first filter plate 52 rotates toward the sand discharge position. When the abutment 56 drives the limit member 571 to fit into the mounting seat 57, the weight accumulated by the first filter plate 52 due to overcoming the force of the reset member 572 is greater than the buoyancy at this time, and the first filter plate 52 can rotate to the sand discharge position faster to clean the sediment, so as to avoid the first filter plate 52 staying in the horizontal state for too long when rotating toward the sand discharge position, and the first filter plate 52 can be more smoothly converted from the water filtration position to the sand discharge position.

[0041] Reference Figure 2 The first filter plate 52 is provided with multiple rows of first filter holes 523, which are arranged at equal intervals along the length direction of the first filter plate 52. A long strip partition plate 55 is slidably attached to the bottom surface of the first filter plate 52, and the sliding direction of the partition plate 55 is perpendicular to the extension direction of the rotation axis of the first filter plate 52. The bottom surface of the first filter plate 52 is provided with slide grooves 524 on both sides of the long side for the partition plate 55 to be embedded. The partition plate 55 is provided with multiple through grooves 551, and the cross section of the through grooves 551 is rectangular. The arrangement direction of the multiple through grooves 551 is parallel to the arrangement direction of the multiple rows of first filter holes 523.

[0042] Reference Figure 2In this embodiment, the plurality of through slots 551 correspond to the plurality of rows of first filter holes 523 one by one, and the distance that the partition plate 55 can move is limited, which is the same as the distance between the centers of each row of first filter holes 523. When the first filter plate 52 is located at the water filtering position, the through slots 551 on the partition plate 55 and the corresponding row of first filter holes 523 are misaligned, and the portion of the partition plate 55 without the through slots 551 closes the first filter holes 523, and the water on the first filter plate 52 can be filtered by the baffle plate 53 and flow into the sedimentation tank 3.

[0043] When the first filter plate 52 rotates to a horizontal state and then continues to rotate toward the sand discharge position, the partition 55 moves toward the sand discharge end 522 of the first filter plate 52 under the action of gravity, and the through groove 551 on the partition 55 is directly opposite to the corresponding first filter hole 523 on the first filter plate 52. Part of the water falling on the first filter plate 52 is mixed with mud and sand and discharged into the collecting tank 6, and part of it falls into the filter tank 51 through the first filter hole 523 and the through groove 551.

[0044] Through the provision of the partition 55, on the one hand, when the amount of water in the filter tank 51 is insufficient to support the first filter plate 52, the water in the water filtering process itself can be used to replenish the filter tank 51, and the first filter plate 52 can smoothly rotate from the sand discharge position to the water filtering position; on the other hand, the amount of water injected into the filter tank 51 does not need to be calculated too accurately, and the water replenished into the filter tank 51 through the first filter plate 52 gradually increases until the first filter plate 52 is reset to the water filtering position after it abuts against and exceeds the limit member 571.

[0045] It should be noted that the upper limit of the buoyancy that the float 54 can provide is determined by the maximum volume of water that the float 54 can displace, that is, the volume of the float 54 itself. When designing the device, it is necessary to comprehensively consider the self-weight of the float 54, the gravity applied by the first filter plate 52 in the unloaded state, and the total reaction force of the reset member 572 in the mounting seat 57.

[0046] Reference Figure 2 A drainage hole 511 is provided on the inner wall of the filter tank 51 near the sedimentation tank 3. The filter tank 51 is connected to the sedimentation tank 3 through the drainage hole 511, and the opening of the drainage hole 511 is higher than the slot height of the sedimentation tank 3, so as to prevent the water in the sedimentation tank 3 from flowing back into the filter tank 51. The part of the water level in the filter tank 51 that exceeds the drainage hole 511 will flow into the sedimentation tank 3, so as to prevent the first filter plate 52 from rotating from the water filtering position to the sand discharge position due to excessive water in the filter tank 51. The rotation cycle of the first filter plate 52 can be smoother, and the silt accumulated on the first filter plate 52 will not accumulate too much and then be cleaned.

[0047] Reference Figure 2 and Figure 4The drainage hole 511 is located at one side of the filter tank 51 and is also provided with a sealing member 512. The sealing member 512 can be pushed to deform and open the drainage hole 511 from the side of the sedimentation tank 3. The water filtering end 521 of the first filter plate 52 is provided with a push rod 58 for pushing the sealing member 512. One end of the push rod 58 is fixedly connected to the first filter plate 52 to rotate with it, and the other end pushes the sealing member 512 to open the drainage hole 511 when the first filter plate 52 is at the water filtering position.

[0048] When the filter tank 51 is in the process of replenishing water, the seal 512 closes the drain hole 511 to allow the first filter plate 52 to gradually rotate to the water filtering position. Only when the first filter plate 52 rotates to the water filtering position, the push rod 58 pushes the seal 512 to open the drain hole 511 to reduce the liquid level of the water in the filter tank 51. The active opening and closing of the drain hole 511 is achieved through the seal 512 and the push rod 58. As for the position of the drain hole 511, its height can be designed to be when the liquid level in the filter tank 51 is reduced to below the drain hole 511. The resistance that limits the first filter plate 52 from the water filtering position to the sand discharge position is borne by the limiter 571 first. In this way, the first filter plate 52 can accumulate less sediment to achieve rotation, and the first filter plate 52 can be more smoothly converted from the water filtering position to the sand discharge position. When the first filter plate 52 rotates away from the water filtering position, the push rod 58 rotates away from the seal 512, and the drainage hole 511 is closed by the seal 512 again. Then, water is replenished in the filter tank 51 to drive the first filter plate 52 to rotate back to the water filtering position, and the cycle continues.

[0049] Reference Figure 4 and Figure 5 Furthermore, without considering the error, the corresponding angle of the arc of the abutment 56 can be set to be equal to the angle of rotation of the first filter plate 52 from the water filtering position to the sand discharge position, minus the angle of the width of the limiter 571 corresponding to the rotation axis of the first filter plate 52. In this way, when the first filter plate 52 is in the sand discharge position, the abutment 56 can still abut against the limiter 571, and by temporarily suspending the rotation of the first filter plate 52, it can accumulate some buoyancy, and the abutment 56 can smoothly pass over the limiter 571 before the partition 55 closes the first filter hole 523, avoiding the situation that the buoyancy of the first filter plate 52 is not enough to support the abutment 56 to pass over the limiter 571 when the water replenishment is stopped due to the closing of the partition 55, thereby ensuring the smooth rotation of the first filter plate 52 from the sand discharge position to the water filtering position.

[0050] Reference Figure 4The outlet pipe 2421 is located above the first filter plate 52 on the side of the water filtering end 521. When the first filter plate 52 is located at the sand discharge position, more sand mainly accumulated near the baffle 53 can be washed away, thereby improving the cleaning effect. At the same time, the flow distance of water on the first filter plate 52 can be extended, so that the water has relatively more sufficient time to fall into the filter tank 51 through the first filter hole 523, thereby improving the efficiency of water replenishment in the filter tank 51.

[0051] Reference Figure 4 Similarly, in order to improve the water replenishment efficiency in the filter tank 51, the side wall of the collecting tank 6 close to the filter tank 51 is set as a second filter plate 61, and the collecting tank 6 and the filter tank 51 are separated by the second filter plate 61. At the same time, the second filter plate 61 is provided with a second filter hole 611 to achieve the communication between the collecting tank 6 and the filter tank 51. The bottom of the second filter plate 61 is located at a height higher than the height of the drainage hole 511 in the filter tank 51. The water flowing into the collecting tank 6 flows into the filter tank 51 after being filtered, which reduces the amount of water accumulated in the collecting tank 6 and speeds up the speed of replenishing water into the filter tank 51.

[0052] Reference Figure 4 The bottom opening of the collecting tank 6 is provided with a flap 62 that rotates, the rotation axis of the flap 62 is horizontally arranged, the flap 62 is suspended and the height from the ground outside the foundation pit 1 is greater than the rotation radius of the flap 62, and a lock 63 is also arranged at the bottom of the collecting tank 6 for opening and closing the flap 62. When there is too much sediment in the collecting tank 6 and it needs to be cleaned, the flap 62 is opened to let the sediment fall out of the collecting tank 6, and it is easier to clean and transport the sediment using common tools on site such as a cart below.

[0053] The implementation principle of this embodiment is as follows: the groundwater extracted by the precipitation module 2 is filtered through the first filter plate 52 and the baffle plate 53 before flowing into the sedimentation tank 3, thereby reducing the influence of the change in the turbidity of the extracted water on the sediment content of the water in the sedimentation tank 3; when a certain amount of sediment accumulates on the first filter plate 52, the first filter plate 52 automatically turns from the water filtering position to the sediment discharge position, and the sediment on the first filter plate 52 is flushed into the collecting tank 6, the weight on the first filter plate 52 is reduced, and at the same time, the water in the filter tank 51 is replenished, and the first filter plate 52 is driven to rotate in the opposite direction through the floating block 54, turning back from the sediment discharge position to the water filtering position, and continuing to filter the groundwater and discharge it into the sedimentation tank 3, and the cycle is carried out.

[0054] A construction method of a foundation pit 1 drainage system is used for the construction of the above-mentioned drainage system, and the steps are as follows: S1. Pipeline layout of precipitation module and recharging module Before excavating the foundation pit 1, firstly, a well point pipe 22 is buried and connected through the drainage main pipe 23. A recharging well pipe 42 is buried on the side of the foundation pit 1 where there is an adjacent building 7 and anti-settling needs to be considered. The recharging well pipe 42 is connected through the recharging main pipe 41. When the foundation pit 1 is excavated to the designed depth, if an open ditch 12 needs to be excavated, the water pipe 21 is used to connect to the drainage main pipe 23. S2. Groove Construction First, a sedimentation tank 3 is excavated in the interval area between the precipitation well pipe and the recharging well pipe 42. The position of the sedimentation tank 3 is biased to the side of the recharging well pipe 42. The water inlet of the recharging main pipe 41 is extended to the bottom of the sedimentation tank 3. The excavation width of the sedimentation tank 3 is controlled to leave enough construction space for the collection tank 6 and the filter tank 51. After that, the filter tank 51 can be constructed at a position adjacent to the sedimentation tank 3 first, and then the collection tank 6 can be constructed with reference to the position of the filter tank 51. S4. Installation of filter module components Two mounting seats 57 are fixed to the notches of the filter tank 51, and the first filter plate 52 is installed between the mounting seats 57. Then, the floating block 54 is connected to the bottom of the first filter plate 52 through a connecting rod 541. According to the position of the water filtering end 521 of the first filter plate 52, a water outlet pipe 2421 of a suitable length is selected to connect to the precipitation main pipe 23, so that the outlet pipe 2421 is located above the first filter plate 52 and above the part on the side of the water filtering end 521 thereof; S4. Debugging of filter module components First, the first filter plate 52 is set at the sand discharge position, and water is poured into the filter tank 51 to raise the floating block 54 until the first filter plate 52 can rotate to the water filtering position, that is, the abutment member 56 on the first filter plate 52 can drive the limiter 571 to be embedded in the mounting seat 57, and at this time the floating block 54 cannot be completely submerged by water. If both conditions are not met, the volume of the floating block 54 or the length of the connecting rod 541 is adjusted according to the situation, or a lighter material is used for the first filter plate 52 and related components to control the overall weight, or the elastic force of the reset member 572 is adjusted; After the above conditions are met, a drainage hole 511 is opened on the side wall of the filter tank 51 near the sedimentation tank 3. The height of the drainage hole 511 is such that when the first filter plate 52 is at the water filtering position, the first filter plate 52 is mainly supported by or can be supported only by the stopper 571. Then, the sealing member 512 is installed and the push rod 58 is installed on the first filter plate 52 according to the position of the drainage hole 511. S5. Cleaning of the collection tank When the silt in the collecting tank 6 needs to be cleaned, the flap 62 at the bottom of the collecting tank 6 is opened to discharge the silt. A tool such as a cart can be placed under the collecting tank 6 in advance to receive the silt for easy transportation.

[0055] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A foundation pit drainage structure, comprising a precipitation module (2) and a recharging module (4), wherein a sedimentation tank (3) is provided between the precipitation module (2) and the recharging module (4), and characterized in that: A filter tank (51) and a collection tank (6) are further provided between the sedimentation tank (3) and the precipitation module (2); the filter tank (51) is located between the collection tank (6) and the sedimentation tank (3); and the water outlet of the precipitation module (2) is located above the filter tank (51); A rotating first filter plate (52) is provided at the notch of the filter tank (51); one end of the first filter plate (52) close to the sedimentation tank (3) is a water filtering end (521); one end of the first filter plate (52) close to the collection tank (6) is a sand discharge end (522); the rotation axis of the first filter plate (52) is horizontally arranged and close to the water filtering end (521); and a baffle (53) for filtering water is provided at the water filtering end (521) of the first filter plate (52); Mounting seats (57) fixed to the notches of the filter tank (51) are respectively provided on both sides of the first filter plate (52); the first filter plate (52) is rotatably connected between the two mounting seats (57); a limiting member (571) is slidably embedded on the mounting seat (57); an abutting member (56) for abutting and driving the limiting member (571) to be embedded in the mounting seat (57) is provided on the first filter plate (52); an elastic member for driving the abutting member (56) to reset is provided in the mounting seat (57); and when the water filtering end (521) of the first filter plate (52) is located lower than the sand discharging end (522), the limiting member (571) is located on a path where the abutting member (56) follows the first filter plate (52) to rotate toward the water filtering end (521) and gradually becomes higher than the sand discharging end (522); a floating block (54) for supporting the first filter plate (52) is also provided in the filter tank (51).

2. A foundation pit drainage structure according to claim 1, characterized in that: The first filter plate (52) is provided with a first filter hole (523), and a partition plate (55) is slidably attached to the bottom surface of the first filter plate (52), wherein the sliding direction of the partition plate (55) is perpendicular to the rotation axis direction of the first filter plate (52), and the partition plate (55) is used to close the first filter hole (523) of the first filter plate (52) when the water filtering end (521) of the first filter plate (52) is lower than the sand discharging end (522).

3. A foundation pit drainage structure according to claim 2, characterized in that: The filter tank (51) is provided with a drainage hole (511) communicating with the sedimentation tank (3), and the position of the drainage hole (511) is higher than the notch of the sedimentation tank (3).

4. A foundation pit drainage structure according to claim 3, characterized in that: The drainage hole (511) is provided with a sealing member (512), and the first filter plate (52) is provided with a push rod (58) for pushing the sealing member (512). When the first filter plate (52) rotates so that the water filtering end (521) is gradually lower than the sand discharging end (522), and the abutting member (56) is able to abut against the limiting member (571) to complete a reciprocating slide, the push rod (58) opens the drainage hole (511) by pushing the sealing member (512).

5. The foundation pit drainage structure according to claim 3, characterized in that: When the water filtering end (521) of the first filter plate (52) is located higher than the sand discharging end (522), the abutment member (56) can abut against the limiting member (571).

6. A foundation pit drainage structure according to claim 2, characterized in that: The water outlet of the precipitation module (2) is located above the first filter plate (52) on the side biased towards the water filtering end (521).

7. The foundation pit drainage structure according to claim 1, characterized in that: A second filter hole (611) is provided on a side wall of the collecting tank (6) close to the filtering tank (51), and the collecting tank (6) is connected to the filtering tank (51) through the second filter hole (611).

8. A foundation pit drainage structure according to claim 7, characterized in that: The bottom of the collecting tank (6) is open and suspended, and a flap (62) for opening and closing the opening is provided at the bottom of the collecting tank (6).

9. A construction method for a foundation pit drainage structure according to claims 1-8, characterized in that: S1, arranging and burying relevant pipelines of the precipitation module (2) and the recharging module (4); S2, a sedimentation tank (3), a filter tank (51) and a collection tank (6) are arranged between the pipelines of the precipitation module (2) and the recharging module (4); S3, installing a first filter plate (52) and a floating block (54) above the notch of the filter tank (51); S4. Pre-inject an appropriate amount of water into the filter tank (51) to adjust the position height of the floating block (54), and support the first filter plate (52) through the floating block (54) so ​​that the water filtering end (521) of the first filter plate (52) is gradually lower than the sand discharge end (522), and the abutment member (56) can be driven to limit the embedded installation seat (57).

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