Pump station front pool drainage pressure reduction structure

Abstract

This utility model relates to the field of water conservancy engineering pump station technology and discloses a seepage reduction and pressure relief structure for a pump station forebay, including: a forebay bottom slab, a seepage ditch, a pressure relief well, and a drainage hole. The forebay bottom slab is a reinforced concrete slab structure that connects to the inlet channel at the front and the pump station body at the rear. A filter layer and geotextile are laid sequentially on the lower part of the bottom slab. At the same time, the lateral extrusion of each layer is prevented by a deeply embedded retaining tooth wall around the perimeter, ensuring the stability and reliability of the filter layer. This utility model effectively reduces the seepage pressure in the pump station forebay by adopting multiple integrated measures, ensuring the stability of the station foundation seepage. The multiple safety defenses solve the problem of easy siltation and failure of traditional seepage reduction and pressure relief facilities, significantly improving the structural reliability and safety of the pump station forebay. The overall structure of the seepage reduction and pressure relief structure is simple in construction, flexible in operation, economical and efficient, and highly universal.

Description

Technical Field

[0001] This utility model relates to the field of water conservancy engineering pump station technology, specifically to a pump station forebay seepage reduction and pressure relief structure. Background Technology

[0002] Pumping stations are key structures in water conservancy projects for benefiting the people and eliminating harm, as well as for flood control and disaster reduction. In particular, large and medium-sized pumping stations play a crucial role in drainage during the flood season and water replenishment during the drought season. The forebay is a smooth area for the diffusion of water flow between the intake channel and the pumping station body. It also usually serves as a seepage outlet for the soil foundation, thereby reducing the pressure of groundwater and releasing the seepage pressure of the foundation. This further prevents seepage damage to the foundation and ensures the safety and stability of the project.

[0003] Currently, most pump station forebays rely solely on small-diameter drainage holes for daily seepage drainage, resulting in limited pressure reduction. Furthermore, the drainage holes are frequently clogged by aquatic plants, floating debris, and other contaminants in the incoming water. Even with trash cans and screens at the end of the intake channel, effective interception of silt and quicksand is impossible, easily leading to clogging and failure of the drainage holes. This results in a simplistic drainage approach with insufficient safety margin. To improve the pressure reduction effect of the pump station forebay, the traditional method involves adding additional pressure-reducing wells to the forebay floor slab, with perforated covers for protection. However, the clogging problem caused by silt, quicksand, and aquatic plants fails to be completely resolved, leading to drainage failure after a short period of operation and a significant reduction in pressure reduction. In engineering practice, if there are no other auxiliary measures for seepage reduction or if the main pressure reduction facilities are blocked due to lack of protection, once the seepage reduction fails, the seepage pressure at the bottom of the forebay will inevitably surge, the seepage gradient in the outflow zone will increase sharply, and it will be very easy to cause sand to boil and water to overflow at the bottom of the forebay, voids in the lower soil layer, and even cause the foundation to sink and tilt, and the foundation to become unstable, thereby affecting the normal use and benefits of the pumping station project.

[0004] To avoid and solve the above problems, this utility model proposes a seepage reduction and pressure relief structure for the pump station forebay. Under the integrated and synergistic effect of multiple measures, it can effectively reduce the seepage pressure in the pump station forebay. The systematic seepage reduction and pressure relief structure complements each other, builds a solid safety defense line, and ensures the stability of the pump station foundation seepage. Through the combined cooperation of the sand-blocking and silt-prevention structure system and the protective check valve, it can successfully solve the problem of failure of traditional seepage reduction and pressure relief facilities due to easy siltation, significantly improve the structural reliability and safety performance of the pump station forebay. The overall structure of the seepage reduction and pressure relief facility is simple, flexible in operation, economical and efficient, and highly universal. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides a seepage reduction and pressure relief structure for pump station forebays. By integrating multiple measures, it can effectively reduce the seepage pressure in the pump station forebay, ensuring stable seepage at the station foundation. The multiple safety defenses solve the persistent problem of easy clogging and failure of traditional seepage reduction and pressure relief facilities, significantly improving the structural reliability and safety of the pump station forebay. The overall structure of the seepage reduction and pressure relief structure is simple, flexible in operation, economical and efficient, and highly versatile.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A seepage and pressure reduction structure for the pump station forebay, comprising: a forebay bottom slab, a seepage ditch, a pressure reduction well, and a drainage hole;

[0008] The forebay bottom slab is a reinforced concrete slab structure that connects the inlet channel to the pump station body. A filter layer and geotextile are laid in sequence under the bottom slab. At the same time, the lateral extrusion of each layer is prevented by the deeply embedded retaining tooth wall around the perimeter, ensuring that the filter layer is stable and reliable. With the synergistic effect of the drainage ditch, pressure relief well and drainage hole, it can effectively reduce the groundwater pressure in the pump station forebay, release the seepage pressure, and ensure the seepage stability of the station foundation.

[0009] The drainage ditch is a trench-type reinforced concrete structure located at the first end of the bottom plate of the forepool, and is cast as a whole with the bottom plate of the forepool. The vertical barrier plate, the horizontal cover panel and the lateral debris net together form a triple three-dimensional protective barrier system, which can effectively intercept silt, sand, floating objects and other debris, prevent the drainage and pressure reduction facilities from becoming clogged and malfunctioning, and ensure continuous and smooth pressure reduction and drainage.

[0010] The pressure relief well is located in the middle of the bottom plate of the forebay. The wellhead protrudes from the bottom plate of the forebay and is equipped with a check valve. Through the filtration and water collection effect of the lower well hole and well pipe, the ground pressurized water can be smoothly discharged. While ensuring the pressure relief and drainage effect, it can also prevent the wellhead from being blocked or other floating objects from entering.

[0011] The drainage holes are filter channels that connect the bottom slab of the forebay and the foundation soil layer. They are distributed in the bottom of the drainage ditch and the area around the pressure relief well. Through several drainage pipes, the underground pressurized water can be filtered and discharged smoothly, so as to achieve the purpose of pressure relief and drainage.

[0012] Preferably, the bottom slab of the forebay is made of C25 reinforced concrete integral structure with a thickness of 0.40m to 0.60m. Three horizontal filter layers are laid on the bottom, all of which are placed within the area enclosed by the retaining tooth wall. An additional layer of filter geotextile is provided between the bottom layer and the foundation soil to increase the safety margin.

[0013] The filter layer consists of gravel with a particle size of 10mm to 20mm, sunflower seed chips with a particle size of 5mm to 10mm, and medium-coarse sand with a particle size of 0.25mm to 2mm from top to bottom, with each layer having a thickness of 200mm to 300mm.

[0014] The geotextile is a polypropylene filament spunbond needle-punched nonwoven geotextile with a nominal strength of 18kN / m to 24kN / m, and is securely fixed to the retaining toothed wall.

[0015] The depth of the retaining toothed wall extends downwards from the bottom surface of the filter layer by 0.10m to 0.20m to prevent lateral extrusion of each layer.

[0016] Preferably, the drainage ditch is integrally cast with the bottom slab of the forepool, a vertical baffle plate is installed on the side of the channel, a horizontal cover panel is installed on the top of the ditch and a lateral debris net is installed at the drainage outlet, and the ditch is filled with boulders for seepage prevention and weight-bearing.

[0017] The retaining vertical plate is a continuous C25 reinforced concrete structure integrally cast with the covering panel. The side plate of the diversion channel adopts a “〗” shape and has an inner arc at the top, so as to prevent the silt from flowing over while retaining sand and preventing silt from being carried away.

[0018] The covering panel has a "Γ"-shaped structure with an inner arc at the top, and the panel thickness is 0.30m to 0.40m;

[0019] The drainage outlet side of the drainage ditch is equipped with several supporting columns, with a clear distance between the columns of 2.00m to 3.00m. The columns are made of square reinforced concrete with a cross-sectional dimension of 0.30m × 0.30m to ensure the safety and stability of the covering panel.

[0020] A debris-blocking net is installed between the supporting columns. The net is made of high-strength, corrosion-resistant stainless steel wire and is connected to the adjacent supporting columns on both sides by bolts.

[0021] Preferably, the lower part of the plurality of pressure relief wells is a circular wellbore with a diameter of 0.40m to 0.50m. After the original soil layer is replaced by medium-coarse sand filter material in the well, the filter material is backfilled to the bottom of the reverse filter layer and compacted. The upper well pipe of the pressure relief well is a single section of C35 reinforced concrete precast pipe.

[0022] The well pipe has the same diameter as the well hole. The inside of the pipe is backfilled and compacted with a mixture of crushed stone and melon seed chips. At the same time, a water-swellable rubber ring is pasted in the middle of the contact surface between the outer wall of the well pipe and the bottom plate of the forebay. This can ensure normal drainage and pressure reduction of the pressure relief well, and prevent underground pressurized water from gushing up along the outer wall of the well pipe and carrying out mud and sand.

[0023] The height of the well pipe protruding from the bottom plate of the forecourt is 0.20m to 0.30m, which is to reserve space for the installation of the check valve. At the same time, a C25 reinforced concrete cast-in-place well ring is used to protect the protruding part, with a wall thickness of 0.20m to 0.30m.

[0024] Preferably, the check valve is installed at the wellhead of several pressure-reducing wells, and is a pre-made or customized duckbill rubber check valve, and is fixedly connected to the well ring with a stainless steel matching flange;

[0025] When the groundwater level in the pressure relief well exceeds the water level in the pump station forebay by more than 0.30m, the check valve automatically opens to drain water and reduce pressure; conversely, the check valve automatically closes due to its elasticity, effectively intercepting floating objects, aquatic plants and other debris in the water flow, and always ensuring that the pressure relief well is free from siltation.

[0026] Preferably, the drainage holes are made by pre-embedding drainage pipes and are arranged in a rectangular pattern at a hole spacing of 1.00m at the bottom of the drainage ditch, and in a quincunx pattern at a hole spacing of 2.00m at the hole spacing of S2 around the pressure relief well.

[0027] The drainage pipe is made of PVC-U structural wall material with a nominal outer diameter of 0.11m to 0.20m, and the bottom of the pipe extends to the middle of the second layer of the reverse filter layer;

[0028] The section of the drainage pipe located within the filter layer is the inlet permeable zone. It adopts a perforated pipe structure with uniformly perforated pipe walls. The outer wall of the perforated holes is wrapped with filter geotextile and fixed by nylon rope. The holes are filled with gravel.

[0029] This utility model provides a seepage drainage and pressure reduction structure for a pump station forebay. Compared with the prior art, it has the following advantages:

[0030] This invention integrates multiple measures, including drainage ditches, pressure-reducing wells, and drainage holes, to form a multi-layered drainage and pressure-reducing system. This significantly improves the drainage and pressure-reducing capacity of the forebay bottom, effectively reduces the seepage pressure in the pump station forebay, and ensures the stability of the pump station foundation. A triple-layered protective barrier system is formed by setting vertical baffles in the drainage ditches, horizontal covering panels, and lateral debris nets. This effectively intercepts silt, quicksand, floating debris, and other contaminants, preventing the drainage and pressure-reducing facilities from becoming clogged and failing. Check valves installed at the pressure-reducing well opening automatically when the groundwater level is high to drain and reduce pressure, and automatically closing when the water level is low without the need for seepage reduction. This effectively solves the problem of easy clogging and failure of traditional pressure-reducing facilities, greatly improving the structural reliability and safety of the pump station forebay. The overall drainage and pressure-reducing structure is simple in construction, flexible and efficient in operation, highly safe and stable, and economically practical. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structural layout of the pump station forebay for seepage reduction and decompression in an embodiment of this utility model;

[0032] Figure 2 This is a schematic longitudinal section of the seepage reduction and dewatering structure of the pump station forebay in an embodiment of this utility model.

[0033] Figure 3 This is a schematic diagram of the drainage ditch structure in an embodiment of this utility model;

[0034] Figure 4 This is a schematic diagram of the pressure relief well structure in an embodiment of this utility model;

[0035] Figure 5 This is a front view of the check valve in an embodiment of this utility model;

[0036] Figure 6 This is a schematic diagram of the drainage hole structure in an embodiment of this utility model;

[0037] Figure 7 This is a top view of the permeable area at the inlet of the drainage hole in an embodiment of this utility model.

[0038] The attached diagram is labeled as follows: forebay bottom plate 10, filter layer 11, geotextile 12, retaining toothed wall 13, drainage ditch 20, retaining vertical plate 21, covering panel 22, supporting column 23, debris net 24, boulders 25, pressure relief well 30, well hole 31, well pipe 32, water-swellable rubber ring 33, check valve 34, drainage hole 40, drainage pipe 41, perforated hole 42. Detailed Implementation

[0039] Example:

[0040] like Figures 1 to 7 As shown, this utility model provides a seepage drainage and pressure reduction structure for a pump station forebay. The seepage drainage and pressure reduction structure includes: a forebay bottom plate 10, a seepage drainage ditch 20, a pressure reduction well 30, and a drainage hole 40.

[0041] The forebay bottom slab 10 is a reinforced concrete slab structure that connects the inlet channel to the pump station body. The bottom of the bottom slab is laid with a filter layer 11 and geotextile 12 in sequence. At the same time, the perimeter deep-embedded retaining toothed wall 13 prevents the lateral extrusion of each layer, ensuring that the filter layer 11 is stable and reliable. With the synergistic effect of the drainage ditch 20, pressure relief well 30 and drainage hole 40, it can effectively reduce the groundwater pressure in the pump station forebay, release the seepage pressure, and ensure the seepage stability of the station foundation.

[0042] The drainage ditch 20 is a grooved reinforced concrete structure located at the head end of the forepool bottom plate 10 and is cast as a whole with the forepool bottom plate 10. The vertical barrier plate 21, the horizontal cover panel 22 and the lateral debris net 24 together form a triple three-dimensional protective barrier system, which can effectively intercept silt, quicksand, floating objects and other debris, prevent the drainage and pressure reduction facilities from becoming clogged and malfunctioning, and ensure continuous and smooth pressure reduction and drainage.

[0043] The pressure relief well 30 is located in the middle of the bottom plate 10 of the forepool. The wellhead protrudes from the bottom plate 10 of the forepool and is equipped with a check valve 34. Through the filtering and water collection function of the lower well hole 31 and well pipe 32, the underground pressurized water can be smoothly discharged. While ensuring the pressure relief and drainage effect, it can also prevent the wellhead from being blocked or other floating objects from entering.

[0044] The drainage hole 40 is a water filtration channel that connects the bottom plate 10 of the forepool and the foundation soil layer. It is distributed in the bottom of the drainage ditch 20 and the area around the pressure relief well 30. Through several drainage pipes 41, the underground pressurized water can be filtered and discharged smoothly to achieve the purpose of pressure relief and drainage.

[0045] like Figures 1-6 As shown, the bottom slab 10 of the forebay adopts a C25 reinforced concrete integral structure with a slab thickness of 0.40m to 0.60m. In this embodiment, a slab thickness of 0.50m is used. A total of 3 horizontal filter layers 11 are laid at the bottom, and all are placed within the area enclosed by the retaining tooth wall 13. A filter geotextile 12 is also provided between the bottom layer and the foundation soil to increase the safety margin.

[0046] The filter layer 11 consists of gravel with a particle size of 10mm to 20mm, sunflower seed chips with a particle size of 5mm to 10mm, and medium-coarse sand with a particle size of 0.25mm to 2mm from top to bottom. The thickness of each layer is 200mm to 300mm. In this embodiment, the thickness of each layer is 200mm.

[0047] Geotextile 12 is made of polypropylene filament spunbond needle-punched nonwoven geotextile with a nominal strength of 18kN / m to 24kN / m, and is securely fixed to the retaining toothed wall 13.

[0048] The depth of the retaining toothed wall 13 extends downward from the bottom surface of the filter layer 11 by 0.10m to 0.20m. In this embodiment, the depth of the retaining toothed wall extends downward from the bottom surface of the filter layer by 0.15m to prevent lateral extrusion of each layer.

[0049] like Figures 1-3 As shown, the drainage ditch 20 and the bottom plate 10 of the forepool are cast as a whole. A vertical baffle plate 21 is installed on the side of the channel. A horizontal cover panel 22 is installed on the top of the ditch and a lateral debris net 24 is installed at the drainage outlet. The ditch is filled with boulders 25 for seepage prevention and weight-bearing. In areas where stone is scarce, concrete irregular blocks can also be used for covering.

[0050] The retaining vertical plate 21 is a continuous C25 reinforced concrete structure integrally cast with the covering panel 22. The side plate of the diversion channel adopts a “〗” shape and has an inner arc at the top, so as to prevent the silt from flowing over while retaining sand and preventing silt from being blocked.

[0051] The covering panel 22 has a "Γ"-shaped structure with an inner arc at the top, and the panel thickness is 0.30m to 0.40m. In this embodiment, the panel thickness is 0.35m.

[0052] Several supporting columns 23 are provided on the drainage outlet side of the drainage ditch 20. The clear distance between the columns is 2.00m to 3.00m. In this embodiment, the clear distance between the columns is 2.50m. A square reinforced concrete structure with a cross-sectional size of 0.30m×0.30m is adopted. Reinforced concrete structures with other cross-sectional sizes can also be selected to ensure that the covering panel 22 is safe and stable.

[0053] A debris-blocking net 24 is installed between the support columns 23. The net is made of high-strength, corrosion-resistant stainless steel wire and is connected to the adjacent support columns 23 on both sides by bolts. Other anchoring methods can also be used for fixing.

[0054] like Figure 2 , Figure 4 As shown, the lower part of several pressure relief wells 30 is a circular well hole 31 with a diameter of 0.40m to 0.50m. In this embodiment, the diameter of the pressure relief well is 0.45m. After the original soil layer is replaced by medium and coarse sand filter material in the hole, the filter material is backfilled to the bottom of the reverse filter layer 11 and compacted. The upper well pipe 32 of the pressure relief well 30 is a single section of C35 reinforced concrete precast pipe.

[0055] The well pipe 32 has the same diameter as the well hole 31. The inside of the pipe is backfilled and compacted with a mixture of crushed stone and melon seed chips. At the same time, a water-swellable rubber ring 33 is pasted in the middle of the contact surface between the outer wall of the well pipe 32 and the bottom plate 10 of the forepool. This can ensure that the pressure relief well 30 can drain and reduce pressure normally, and also prevent the underground pressurized water from gushing up along the outer wall of the well pipe 32 and carrying out mud and sand.

[0056] The height of the well pipe 32 protruding from the bottom plate 10 of the forebay is 0.20m to 0.30m. In this embodiment, the height of the well pipe protruding from the bottom plate of the forebay is 0.25m, which is reserved space for the installation of the check valve 34. At the same time, a C25 reinforced concrete cast-in-place well ring is used to protect the protruding part, with a wall thickness of 0.20m to 0.30m. In this embodiment, the C25 reinforced concrete cast-in-place well ring used to protect the protruding part has a wall thickness of 0.25m.

[0057] like Figure 4 , Figure 5 As shown, check valve 34 is installed at the wellhead of several pressure relief wells 30. It is a prefabricated or customized duckbill rubber check valve and is fixedly connected to the well ring with a stainless steel matching flange.

[0058] In this embodiment, when the groundwater level in the pressure relief well 30 exceeds the water level in the pump station forebay by more than 0.30m, the check valve 34 automatically opens to drain and reduce pressure; conversely, the check valve 34 automatically closes under its own elasticity, effectively intercepting floating objects, aquatic plants and other debris in the water flow, and always ensuring that the pressure relief well 30 is free from siltation. In pressure relief structures of the same proportion but different sizes, the height by which the pressurized water level exceeds the water level in the pump station forebay is not a fixed value, but is determined according to the actual situation.

[0059] like Figure 1 , Figure 2 As shown, the drainage holes 40 are made by pre-embedding drainage pipes 41, and are arranged in a rectangular pattern at the bottom of the drainage ditch 20 with a hole spacing of 1.00m (S1). They are also arranged in a quincunx pattern around the pressure relief well 30 with a hole spacing of 2.00m (S2). The hole spacings S1 and S2 are not fixed values ​​and can be other appropriate sizes depending on the actual situation.

[0060] like Figure 6 , Figure 7 As shown, the drainage pipe 41 is made of PVC-U structural wall pipe, but other drainage building pipes can also be used. The nominal outer diameter is 0.11m to 0.20m, and the bottom of the pipe extends to the middle of the second layer of the filter layer 11.

[0061] The section of the drainage pipe 41 located within the filter layer 11 is the inlet permeable zone. It adopts a perforated pipe structure with uniformly perforated pipe walls. The outer wall of the perforated holes 42 is wrapped with filter geotextile and fixed by nylon rope. The holes are filled with gravel.

[0062] In this embodiment of the invention, a multi-layered drainage and pressure reduction system is formed by integrating and coordinating multiple measures such as drainage ditches 20, several pressure-reducing wells 30, and drainage holes 40. This system can significantly improve the drainage and pressure reduction capacity of the forebay bottom plate 10, effectively reduce the seepage pressure of the pump station forebay, and ensure the stability of the station foundation's seepage. By setting the vertical barrier plate 21, horizontal cover panel 22, and lateral debris net 24 of the drainage ditches 20, a triple three-dimensional protective barrier system is formed, which can effectively intercept silt, quicksand, floating debris, and other impurities, preventing the drainage and pressure reduction facilities from becoming clogged and failing. The check valve 34 installed at the wellhead of the pressure-reducing well 30 can automatically open to drain and reduce pressure when the groundwater is at a high level, and automatically close without the need for seepage reduction when the water level is low. This effectively solves the problem of easy clogging and failure of traditional pressure-reducing facilities, and greatly improves the structural reliability and safety of the pump station forebay. The drainage and pressure reduction structure has a simple overall structure, is flexible and efficient in operation, has high safety and stability, and is economical and practical.

Claims

1. A seepage reduction and pressure relief structure for a pump station forebay, characterized in that, include: Forepool bottom plate (10), drainage ditch (20), pressure relief well (30) and drainage hole (40); The forebay bottom plate (10) is a reinforced concrete slab structure with a front water intake channel and a rear pump station body. The bottom of the bottom plate is laid with a filter layer (11) and geotextile (12) in sequence. At the same time, the lateral extrusion of each layer is prevented by the perimeter deeply embedded retaining tooth wall (13), ensuring that the filter layer (11) is stable and reliable. With the synergistic effect of the drainage ditch (20), pressure relief well (30) and drainage hole (40), the groundwater in the forebay of the pump station can be effectively reduced, the seepage pressure is released, and the seepage stability of the station foundation is ensured. The drainage ditch (20) is a grooved reinforced concrete structure located at the head end of the forepool bottom plate (10), and is cast as a whole with the forepool bottom plate (10). The vertical barrier plate (21), the horizontal cover panel (22) and the lateral debris net (24) together form a triple three-dimensional protective barrier system. The pressure relief well (30) is located in the middle of the bottom plate (10) of the forepool. The wellhead protrudes from the bottom plate (10) of the forepool and is equipped with a check valve (34). It collects water through the filtration effect of the lower well hole (31) and the well pipe (32). The drainage holes (40) are water filtration channels that connect the bottom plate (10) of the forepool and the foundation soil layer. They are distributed in the bottom of the drainage ditch (20) and the surrounding area of ​​the pressure relief well (30). The underground pressurized water can be filtered and discharged smoothly through several drainage pipes (41).

2. The pump station forebay seepage reduction and pressure relief structure as described in claim 1, characterized in that, The bottom slab (10) of the forepool adopts a C25 reinforced concrete integral structure with a thickness of 0.40m to 0.60m. Three horizontal filter layers (11) are laid on the bottom, and all are placed in the area enclosed by the retaining tooth wall (13). A filter geotextile (12) is set between the bottom layer and the foundation soil to increase the safety margin. The filter layer (11) consists of gravel with a particle size of 10mm to 20mm, melon seed chips with a particle size of 5mm to 10mm, and medium-coarse sand with a particle size of 0.25mm to 2mm from top to bottom, with each layer having a thickness of 200mm to 300mm. The geotextile (12) is a polypropylene filament spunbond needle-punched nonwoven geotextile with a nominal strength of 18kN / m to 24kN / m, and is securely fixed to the retaining toothed wall (13). The depth of the retaining toothed wall (13) extends downward from the bottom surface of the filter layer (11) by 0.10m to 0.20m to prevent lateral extrusion of each layer.

3. The pump station forebay seepage reduction and pressure relief structure as described in claim 1, characterized in that, The drainage ditch (20) and the bottom plate (10) of the forepool are cast as a whole. A vertical barrier plate (21) is installed on the side of the channel, a horizontal cover panel (22) is installed on the top of the ditch, and a lateral debris net (24) is installed at the drainage outlet. The ditch is filled with boulders (25) for seepage prevention and weight-bearing. The vertical retaining plate (21) is a continuous C25 reinforced concrete structure integrally cast with the covering panel (22). The side panel of the channel adopts a “〗” shape and has an inner arc at the top, so as to prevent the silt from flowing over while retaining sand and blocking silt. The covering panel (22) has a "Γ"-shaped structure with an inner arc at the top, and the panel thickness is 0.30m to 0.40m; The drainage outlet side of the drainage ditch (20) is provided with several supporting columns (23), with a net distance of 2.00m to 3.00m between the columns. The columns are made of square reinforced concrete with a cross-sectional dimension of 0.30m × 0.30m to ensure that the covering panel (22) is safe and stable. A debris-blocking net (24) is installed between the supporting columns (23). The net is made of high-strength, corrosion-resistant stainless steel wire and is connected to the adjacent supporting columns (23) on both sides by bolts.

4. The pump station forebay seepage reduction and pressure relief structure as described in claim 1, characterized in that, The lower part of the several pressure relief wells (30) is a circular well hole (31) with a diameter of 0.40m to 0.50m. After the original soil layer is replaced by medium and coarse sand filter material in the hole, the filter material is backfilled to the bottom of the reverse filter layer (11) and compacted. The upper well pipe (32) of the pressure relief well (30) is a single section of C35 reinforced concrete precast pipe. The well pipe (32) has the same diameter as the well hole (31). The inside of the pipe is backfilled and compacted with a mixture of crushed stone and melon seed chips. At the same time, a water-swellable rubber ring (33) is pasted in the middle of the contact surface between the outer wall of the well pipe (32) and the bottom plate (10) of the front pool. This can ensure normal drainage and pressure reduction of the pressure relief well (30) and prevent underground pressurized water from gushing up along the outer wall of the well pipe (32) and carrying out mud and sand. The well pipe (32) protrudes from the bottom plate (10) of the pool by 0.20m to 0.30m, which is reserved space for the installation of the check valve (34). At the same time, a C25 reinforced concrete cast-in-place well ring is used to protect the protruding part with a wall thickness of 0.20m to 0.30m.

5. The pump station forebay seepage reduction and pressure relief structure as described in claim 1, characterized in that, The check valve (34) is installed at the wellhead of several pressure relief wells (30), using a pre-made or customized duckbill rubber check valve, and is fixedly connected to the well ring with a stainless steel matching flange; When the groundwater level in the pressure relief well (30) exceeds the water level in the pump station forebay by more than 0.30m, the check valve (34) automatically opens to drain water and reduce pressure; otherwise, the check valve (34) automatically closes under its own elasticity, effectively intercepting floating objects, aquatic plants and other debris in the water flow, and always ensuring that the pressure relief well (30) is free from siltation.

6. The pump station forebay seepage reduction and pressure relief structure as described in claim 1, characterized in that, The drainage holes (40) are made by pre-embedding drainage pipes (41) and are arranged in a rectangular pattern at the bottom of the drainage ditch (20) with a hole spacing of 1.00m (S1), and in a plum blossom pattern at the hole spacing of 2.00m (S2) around the pressure relief well (30).

7. The pump station forebay seepage reduction and pressure relief structure as described in claim 1, characterized in that, The drainage pipe (41) is made of PVC-U structural wall material with a nominal outer diameter of 0.11m to 0.20m and the bottom of the pipe extends to the middle of the second layer of the filter layer (11). The section of the drainage pipe (41) within the filter layer (11) is the inlet permeable zone. It adopts a perforated pipe structure with uniform openings in the pipe wall. The outer wall of the perforated hole (42) is wrapped with filter geotextile and fixed by nylon rope. The hole is filled with gravel.

Images