A layered ecological water retaining structure of a multi-stage gravel filter dam

Abstract

The utility model relates to water conservancy engineering technical field, concretely to a kind of layered ecological water retaining structure of multistage gravel filter dam, including river channel, two filter dams are arranged in the river channel, the both sides of the bottom of two filter dams are provided with gabion, water collection area is formed between two filter dams, the side of filter dam in rear side is provided with water outlet section, steel mesh is fixedly installed on the slope of the both sides of filter dam;The filter dam is trapezoidal cross section, the layered ecological water retaining structure of multistage gravel filter dam, large particle suspended solids can be intercepted by ecological soil layer, middle layer coarse gravel layer filters middle particle impurities, lower layer fine gravel layer intercepts fine particle suspended solids, while the vegetation root system of ecological vegetation zone can adsorb nitrogen and phosphorus pollutants, improve water transparency, total nitrogen removal rate is high, and diversified ecological system can be constructed, can attract fish, amphibian, bird and other biological habitat, improve regional biodiversity.

Description

Technical Field

[0001] This utility model relates to the field of water conservancy engineering technology, specifically to a layered ecological water-blocking structure for a multi-stage gravel filter dam. Background Technology

[0002] In small and medium-sized watershed management, agricultural non-point source pollution control, and ecological restoration projects, dams are commonly used water conservancy facilities. Their core functions include impounding floodwaters, regulating runoff, and reducing soil erosion. Traditional dams mostly use rigid structures such as concrete and masonry, which, while possessing strong water impoundment and erosion resistance capabilities, are not eco-friendly. On the one hand, the rigid dam body blocks the exchange of substances between water and soil, destroying the habitats of aquatic organisms; on the other hand, it cannot filter suspended solids, nitrogen, phosphorus, and other pollutants in the runoff, making it difficult to improve the water quality downstream.

[0003] To address the aforementioned issues, gravel filter dams have emerged in existing technologies. These dams utilize the pores of gravel to achieve both filtration and water permeability, while simultaneously improving ecological balance. However, existing gravel filter dams often employ a single-size or randomly graded pile of gravel, resulting in uneven distribution of filter pores. Large pores easily allow suspended solids to pass through, while small pores are prone to clogging and sedimentation, leading to a significant decrease in filtration efficiency after long-term use. Utility Model Content

[0004] In view of the problems existing in the prior art, this utility model discloses a layered ecological water-blocking structure of a multi-stage gravel filter dam. The technical solution adopted is as follows: it includes a river channel, in which two filter dams are set. Both sides of the bottom of the two filter dams are provided with gabions, and a water catchment area is formed between the two filter dams. A water outlet section is set on one side of the rear filter dam. Wire mesh is fixedly installed on the inclined surfaces on both sides of the filter dam. The filter dam has a trapezoidal cross-section, and the filter dam body is divided into an ecological soil layer, a coarse gravel layer, and a fine gravel layer from top to bottom along the vertical direction.

[0005] As a preferred technical solution of this utility model, the ecological soil layer is 20-30cm thick and is made of loam and humus mixed in a volume ratio of 3:1. Moisture-tolerant herbaceous plants are planted in the ecological soil layer.

[0006] As a preferred technical solution of this utility model, several drainage pipes are pre-embedded in the ecological soil layer, and the diameter of the drainage pipes is 20mm.

[0007] As a preferred technical solution of this utility model, a fine sand layer is provided at the bottom of the water catchment area, the thickness of the fine sand layer is 15cm, and emergent plants and floating-leaved plants are planted in the water catchment area.

[0008] As a preferred embodiment of this utility model, the coarse gravel layer is granite gravel with a particle size of 50-100mm and a porosity of 35%-40%.

[0009] As a preferred embodiment of this utility model, the fine gravel layer is quartz sand with a particle size of 10-30mm and a porosity of 25%-30%.

[0010] As a preferred technical solution of this utility model, the top of the filter dam is provided with an ecological vegetation belt, which is planted with a mixed community of shrubs and herbaceous plants.

[0011] As a preferred technical solution of this utility model, the bottom of the filter dam is provided with an anti-seepage layer, which is a composite structure of HDPE geomembrane and compacted clay, with a thickness of 10-15cm.

[0012] The beneficial effects of this utility model are as follows: 1. This utility model uses an ecological soil layer to intercept large suspended particles, a middle coarse gravel layer to filter medium-sized particulate impurities, and a lower fine gravel layer to intercept fine suspended particles. Simultaneously, the root system of the ecological vegetation belt can adsorb nitrogen and phosphorus pollutants, improving water transparency and achieving a high total nitrogen removal rate. Through the three-dimensional planting configuration of aquatic plants in the catchment area and shrubs on the dam top, a diverse ecosystem can be constructed, attracting fish, amphibians, birds, and other organisms to inhabit the area, thus enhancing regional biodiversity. Furthermore, the permeable dam body retains the natural infiltration function of the water body, maintaining the hydrological connectivity of the river channel.

[0013] 2. By combining the seepage-proof layer with the metal mesh, dam deformation and leakage can be effectively prevented; excess water in the ecological soil layer can be drained through the drainage pipe to prevent plant root rot.

[0014] 3. Two-stage filtration dams can impound 50%-60% of the total runoff during the flood season. Through the pores of the fine gravel layer and the coarse gravel layer and the synergistic effect with the catchment area, water can be impounded, slowly infiltrated, and gradually discharged, which can meet the downstream ecological water demand and reduce the problem of water shortage during the drought period. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the cross-sectional structure of the ecological blue water structure of this utility model; Figure 3 This is a schematic diagram of the cross-sectional structure of the filter dam of this utility model.

[0016] In the diagram: 1. River channel, 2. Filter dam, 21. Fine gravel layer, 22. Coarse gravel layer, 23. Ecological soil layer, 3. Gabion, 4. Catchment area, 5. Outflow section, 6. Fine sand layer, 7. Drainage pipe, 8. Ecological vegetation belt, 9. Impermeable layer, 10. Wire mesh. Detailed Implementation

[0017] Example 1 like Figures 1 to 3 As shown, this utility model discloses a layered ecological water-blocking structure for a multi-stage gravel filter dam. The technical solution adopted includes a river channel 1, with two filter dams 2 set in the river channel 1. Gabions 3 are set on both sides of the bottom of the two filter dams 2, forming a water catchment area 4 between the two filter dams 2. A water outlet section 5 is set on one side of the rear filter dam 2. Wire mesh 10 is fixedly installed on the inclined surfaces on both sides of the filter dam 2. A fine sand layer 6 with a thickness of 15cm is set at the bottom of the water catchment area 4. Emergent plants and floating-leaved plants are planted in the water catchment area 4. An ecological vegetation belt 8 is set on the top of the filter dam 2, which is a mixed community of shrubs and herbaceous plants. An impermeable layer 9 is set at the bottom of the filter dam 2. The impermeable layer 9 is a composite structure of HDPE geomembrane and compacted clay with a thickness of 10-15cm. The filter dam 2 has a trapezoidal cross-section. The filter dam body 2 is divided into an ecological soil layer 23, a coarse gravel layer 22, and a fine gravel layer 21 from top to bottom along the vertical direction. The ecological soil layer 23 is 20-30cm thick and is made of loam and humus mixed in a volume ratio of 3:1. Moisture-tolerant herbaceous plants are planted in the ecological soil layer 23. Several drainage pipes 7 are pre-buried in the ecological soil layer. The diameter of the drainage pipes 7 is 20mm. The coarse gravel layer 22 is made of granite gravel with a particle size of 50-100mm and a porosity of 35%-40%. The fine gravel layer 21 is made of quartz sand with a particle size of 10-30mm and a porosity of 25%-30%.

[0018] The working principle of this utility model is as follows: The river runoff 1 first flows through the first filter dam 2. The dam body has an ecological soil layer 23 with a thickness of 20-30cm from top to bottom. It is made of loam and humus mixed in a volume ratio of 3:1. Moisture-tolerant herbaceous plants are planted inside, and a 20mm diameter drainage pipe 7 is pre-buried. Large particles of suspended matter are intercepted first, and the roots of the vegetation absorb nitrogen and phosphorus pollutants. The drainage pipe 7 discharges excess water to prevent plant root rot. Next, the water enters the coarse gravel layer 22, which intercepts medium-sized particles of impurities and ensures permeability and dam support. Then it enters the fine gravel layer 21, which intercepts fine particles of suspended matter and absorbs nitrogen and phosphorus ions through ion exchange. At the same time, the steel wire mesh on both sides of the filter dam fixes the dam body, and the bottom HDPE geomembrane and compacted clay composite seepage prevention layer 9 prevents leakage. The gabions 3 on both sides of the bottom enhance the dam foundation's erosion resistance. Subsequently, the water flows into the catchment area 4 between the two filter dams 2. The bottom 15cm thick fine sand layer of the catchment area 4 performs secondary filtration. Emergent plants and floating-leaved plants in the catchment area 4 further enhance the dam's erosion resistance. The first stage purifies the water and temporarily stores the water to buffer the flow. Then, the water enters a second filtration dam 2, which has the same structure as the first, for deeper purification. This creates a two-stage filtration effect, increasing the pollutant removal rate. The protective structure of the second filtration dam 2 works in conjunction with the first filtration dam to ensure overall stability. Finally, the water is discharged in an orderly manner through the outlet section 5 on one side of the second filtration dam 2. The two filtration dams 2, together with the catchment area 4, can intercept 50%-60% of the total runoff during the flood season. During the flood season, the water is temporarily stored, and during the drought season, water is slowly infiltrated to supply water to meet downstream ecological water needs. Simultaneously, an ecological vegetation belt of mixed shrubs and herbs is planted on the dam top, forming a three-dimensional vegetation system of terrestrial, wetland, and aquatic vegetation with the vegetation in the catchment area and ecological soil layer. This provides habitats for various organisms, enhancing biodiversity. The permeable dam also restores the river's hydrological connectivity and material cycle. The graded pore design prevents large particles from clogging the fine pores, and combined with biological self-purification, it helps reduce siltation, effectively ensuring the long-term operation of the structure.

[0019] Components not described in detail in this article are existing technologies.

[0020] While the specific embodiments of this utility model have been described in detail above, this utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this utility model. Modifications or variations that do not involve creative labor are still within the protection scope of this utility model.

Claims

1. A layered ecological water-retaining structure for a multi-stage gravel filter dam, comprising a river channel (1), characterized in that, Two filter dams (2) are set in the river channel (1). Gabions (3) are set on both sides of the bottom of the two filter dams (2). A water catchment area (4) is formed between the two filter dams (2). A water outlet section (5) is set on one side of the filter dam (2) on the rear side. Wire mesh (10) is fixedly installed on the slopes on both sides of the filter dam (2). The filter dam (2) has a trapezoidal cross-section and is divided into an ecological soil layer (23), a coarse gravel layer (22) and a fine gravel layer (21) from top to bottom along the vertical direction.

2. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 1, characterized in that: The ecological soil layer (23) is 20-30cm thick and is made of loam and humus mixed in a volume ratio of 3:

1. Moisture-tolerant herbaceous plants are planted in the ecological soil layer (23).

3. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 2, characterized in that: Several drainage pipes (7) are pre-embedded in the ecological soil layer, and the diameter of the drainage pipes (7) is 20mm.

4. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 1, characterized in that: The bottom of the catchment area (4) is provided with a fine sand layer (6) with a thickness of 15cm. Emergent plants and floating-leaved plants are planted in the catchment area (4).

5. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 1, characterized in that: The coarse gravel layer (22) consists of granite gravel with a particle size of 50-100 mm and a porosity of 35%-40%.

6. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 1, characterized in that: The fine gravel layer (21) consists of quartz sand gravel with a particle size of 10-30 mm and a porosity of 25%-30%.

7. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 1, characterized in that: The top of the filter dam (2) is provided with an ecological vegetation belt (8) for planting a mixed community of shrubs and herbaceous plants.

8. The layered ecological water-retaining structure of a multi-stage gravel filter dam according to claim 1, characterized in that: The bottom of the filter dam (2) is provided with an impermeable layer (9), which is a composite structure of HDPE geomembrane and compacted clay with a thickness of 10-15cm.

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