CN213086979U

CN213086979U - Novel biological detention pond using permeable geotextile as transition layer

Info

Publication number: CN213086979U
Application number: CN202020894577.2U
Authority: CN
Inventors: 陈满军; 龚金龙; 刘泷; 崔咏军; 傅大放
Original assignee: KUNSHAN CONSTRUCT ENGINEERING QUALITY TESTING CENTER
Current assignee: KUNSHAN CONSTRUCT ENGINEERING QUALITY TESTING CENTER
Priority date: 2020-05-25
Filing date: 2020-05-25
Publication date: 2021-04-30
Anticipated expiration: 2030-05-25

Abstract

The utility model discloses an utilize geotechnological cloth that permeates water as novel biological detention pond of transition layer, including the cell body, from the top down has laid the filter layer in proper order in the cell body, has permeated water geotechnological cloth, drainage blanket, the top reservation of cell body has rainwater detention district, the perforation drain pipe has been laid to the bottom of cell body. The utility model discloses a geotechnological cloth that permeates water replaces having the coarse sand to lay the transition layer that forms among the prior art, geotechnological cloth that permeates water has the cost cheap, construction convenience, stable performance, advantages such as the quantity is few, can stay filler in geotechnological cloth top of permeating water in smooth and easy drainage in being used in biological detention pond, be applicable to biological detention pond, adopt geotechnological cloth that permeates water to replace the transition layer, the efficiency in original biological detention pond has been guaranteed, only need during the construction accomplish the back at the drainage blanket, geotechnological cloth that will permeate water is levelly and smoothly placed and can begin to fill the filter layer filler on the gravel, the construction quality of assurance filter layer that can be better, high efficiency, reduce engineering cost.

Description

Novel biological detention pond using permeable geotextile as transition layer

Technical Field

The utility model relates to a biological detention pond field, concretely relates to utilize novel biological detention pond of geotechnological cloth as transition layer that permeates water

Background

The sponge city is a new generation of urban rainfall flood management concept, follows principles of ecological priority and the like, combines natural approaches with artificial measures, realizes accumulation, permeation and purification of rainwater in urban areas to the maximum extent on the premise of ensuring urban drainage waterlogging prevention safety, and promotes utilization of rainwater resources and ecological environment protection. The construction of the sponge city is not a way of putting down the weight to replace the traditional drainage system, but is a way of reducing the burden and supplementing the traditional drainage system, the self effect of the city is exerted to the maximum extent, water can be absorbed, stored, seeped and purified when raining, and the stored water is released and utilized when needed.

The biological detention pond is a facility which is arranged in a lower region of the terrain, stores, seeps and purifies runoff rainwater through a plant, soil and microorganism system, and is a key technology in sponge city construction. Referring to fig. 1, when the traditional biological retention pond is constructed, the drainage layer, the transition layer and the filter layer need to be filled, compacted, leveled and controlled in elevation layer by layer, the transition layer in the prior art is laid by coarse sand, the construction complexity is changed, the construction procedures are multiple, the requirement is high, the time is long, and the material cost and the labor cost are high.

Therefore, a novel biological detention pond which is simple in structural form, improves construction convenience, reduces construction cost and does not reduce efficiency needs to be designed and developed urgently.

Disclosure of Invention

The to-be-solved technical problem of the utility model is to provide an utilize geotechnological cloth that permeates water as the novel biological detention pond of transition layer, adopt to permeate water geotechnological cloth to replace and have the coarse sand to lay the transition layer that forms among the prior art, guaranteed the efficiency in original biological detention pond, reduce the complexity of construction, reduced construction cost and material cost, practice thrift the engineering time.

In order to solve the technical problem, the utility model provides an utilize geotechnological cloth that permeates water as novel biological detention pond of transition layer, including the cell body, from the top down has laid filter layer, geotechnological cloth, the drainage blanket that permeates water in proper order in the cell body, the top reservation of cell body has rainwater detention district, the perforation drain pipe has been laid to the bottom of cell body.

The utility model discloses a preferred embodiment, further include the filter layer comprises coarse sand of continuous gradation, middlings of continuous gradation and fine sand of continuous gradation, and wherein the weight percent of coarse sand, middlings, fine sand is: 5:2:3, and 3% of nutrient soil by volume is added into the filter layer.

In a preferred embodiment of the present invention, the thickness of the filter layer is 600 mm.

In a preferred embodiment of the present invention, the drainage layer is made of gravel with a diameter of 3-5 mm.

In a preferred embodiment of the present invention, the thickness of the drainage layer is 200 mm.

In a preferred embodiment of the present invention, the filter layer is further planted with landscape ornamental plants above.

In a preferred embodiment of the present invention, the perforated drain pipe further has a hole diameter of 3mm, and the perforated distance is 20 mm.

In a preferred embodiment of the present invention, an overflow pipe is disposed on the upper side wall of the tank body.

The utility model has the advantages that:

the utility model adopts the permeable geotextile to replace the transition layer formed by coarse sand laying in the prior art, the permeable geotextile has the functions of drainage, filtration, isolation and the like, and is widely applied to the projects such as earth dams, road beds, retaining walls, soft soil foundations, slope protection cushion layers, drainage underdrains, drainage pipes and the like, the permeable geotextile is used in the bioretention pond, the filler can be left above the permeable geotextile while the water is smoothly drained, the permeable geotextile is used for replacing a transition layer, the efficiency of the original bioretention pond is ensured, and the construction is only completed after the drainage layer is constructed, the filter layer filler can be filled by flatly placing the permeable geotextile on the gravel, so that the construction quality of the filter layer can be better ensured, the efficiency is improved, and the construction cost is reduced.

Drawings

FIG. 1 is a schematic view of a structure of a conventional bioretention pond;

fig. 2 is a schematic structural view of the novel bioretention pond of the present invention using permeable geotextile as a transition layer;

fig. 3 is a schematic structural view of the perforated drain pipe of the present invention.

The reference numbers in the figures illustrate: 1. a tank body; 2. a rainwater retention zone; 3. a filter layer; 4. water-permeable geotextile; 5. a drainage layer; 6. a perforated drain pipe; 7. an overflow pipe; 8. and a transition layer.

Detailed Description

The present invention is further described with reference to the following drawings and specific embodiments so that those skilled in the art can better understand the present invention and can implement the present invention, but the embodiments are not to be construed as limiting the present invention.

Referring to fig. 2, an embodiment of the novel bioretention pond using permeable geotextile as a transition layer of the present invention comprises a pond body 1, the tank body 1 is a cube with the length, width and height of 1000mm, a filter layer 3, a permeable geotextile 4 and a drainage layer 5 are sequentially laid in the tank body 1 from top to bottom, a rainwater detention area 2 is reserved at the top of the tank body 1, a perforated drain pipe 6 is laid at the bottom of the tank body 1, an overflow pipe 7 is further arranged on the side wall above the tank body 1, rainwater enters the tank body 1 from the top of the tank body 1, sequentially passes through the filter layer 3, the permeable geotextile 4 and the drainage layer 5 to realize the collection and treatment of rainwater, finally flows into the perforated drainage pipe 6 and is discharged into a municipal pipeline, when the bioretention pond is saturated or the water inflow is excessive in the moment, in order to prevent the ponding, the rivers are discharged from overflow pipe 7 at the top.

Specifically, the filter layer 3 is composed of coarse sand of continuous gradation, medium sand of continuous gradation, and fine sand of continuous gradation, wherein the coarse sand, the medium sand, and the fine sand are in percentage by weight: 5:2:3, and nutrient soil with the volume ratio of 3% is added into the filter layer 3, coarse sand, medium sand and fine sand adopted by the filter layer 3 in the embodiment are in continuous gradation instead of being screened into several grades of materials with different particle size ranges, a natural sand structure is not damaged, and the obtained mixture structure is more stable than the existing mixture ratio, is more resistant to rain washing, and cannot cause structural layer damage caused by sand material loss, so that the permeation coefficient is increased, and the hydrological water quality effect is reduced.

Specifically, in order to ensure the efficiency of the bioretention pond, the filling height in the bioretention pond is to reach 800mm, in this embodiment, the permeable geotextile 4 is used to replace the transition layer 8, and in order to meet the height requirement of the bioretention pond, in this embodiment, the thickness of the filter layer 3 is 600 mm.

In the embodiment, the drainage layer 5 is composed of gravels with the grain diameter of 3-5mm, and the thickness of the drainage layer 5 is 200mm, which is the same as that of the drainage layer 5 in the traditional biological retention pool.

Referring to fig. 3, the perforated drain pipe 6 has a perforated aperture of 3mm and a perforated interval of 20mm, and the perforated drain pipe 6 is communicated with a municipal pipeline.

The bioretention pond mainly judges the efficiency of the bioretention pond from three directions: hydrologic effect, water quality effect and vegetation condition, wherein, hydrologic effect determines the water storage capacity of bioretention pond, the water quality effect determines the filtration capacity of bioretention pond, the vegetation condition determines the applicable condition of bioretention pond.

This application adopts geotechnological cloth 4 that permeates water to replace and has the coarse sand to lay the transition layer 8 that forms among the prior art, has done the experiment comparison respectively to above-mentioned three kinds of efficiency:

1. hydrological effect

The judgment criteria of the hydrological effect comprise runoff producing time, overflow starting time, peak reduction rate, runoff control rate and runoff reduction rate, 3 experiments with different rainfall intensities and 3 experiments with different rainfall times are respectively set for the judgment criteria, and the experimental data refer to tables 1 and 2 (wherein D0 represents a traditional bioretention pond, D1 represents a bioretention pond of the application, and a represents unit rainfall):

table 1: flow control effect of bioretention tanks with different rainfall intensities

Table 2: flow control effect of bioretention pool for different rainfall duration

As can be seen from the data obtained in the above table, the conventional bioretention pond and the bioretention pond of the present application have almost no difference in the criterion of the hydrological effect.

2. Effect of water quality

The evaluation standard of the water quality effect mainly comprises the determination of COD and NH₄ ⁺The removal effect of four pollutants of-N, TN and TP. COD is an important index for evaluating organic matter pollution of a water body, nitrogen and phosphorus are necessary nutrients for growth of microorganisms and animals and plants in the water, eutrophication of the water body, black and odorous water body and the like are easily caused by excessive content of nitrogen and phosphorus, and for the evaluation standards, the removal rate of pollutants and the concentration of effluent pollutants refer to tables 3 and 4 (wherein D0 represents a traditional bioretention pool, and D1 represents the bioretention pool of the application):

table 3: average removal rate of pollutants in each bioretention pond

Table 4: average concentration (mg/l) of pollutants in effluent of each bioretention pond

From the data that obtain in the table, the biological detention pond of traditional biological detention pond and this application almost differs little on the criterion of quality of water effect, because the biological detention pond of this application has increased the thickness of filter layer 3, the biological detention pond of this application is more obvious in the effect to the pollutant filtering for traditional biological detention pond.

3. Growth conditions of plants

Specifically, a landscape ornamental plant is planted above the filter layer 3, the landscape ornamental plant planted in this embodiment is an acorus calamus plant, and for comparison, the same calamus plant is also planted in the traditional bioretention pond under the same conditions, and the specific growth conditions are shown in table 5 (wherein D0 represents the traditional bioretention pond, and D1 represents the bioretention pond of the present application):

table 5: biomass of calamus plant (unit: g)

As can be seen from the data obtained in the above table, the bioretention pond of the present application does not affect the normal growth of the plants.

Can draw the conclusion by above-mentioned three experiment, the biological detention pond of this application can guarantee for traditional biological detention pond that efficiency is unchangeable, on this basis, adopt geotechnological cloth 4 that permeates water to replace and have the coarse sand to lay the transition layer 8 that forms among the prior art, only need during the construction accomplish the back at drainage blanket 6 construction, will permeate water geotechnological cloth 4 smooth place can begin to fill filter layer 3 filler on the gravel, guarantee filter layer 3's that can be better construction quality, raise the efficiency.

The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. Equivalent substitutes or changes made by the technical personnel in the technical field on the basis of the utility model are all within the protection scope of the utility model. The protection scope of the present invention is subject to the claims.

Claims

1. The utility model provides an utilize geotechnological cloth that permeates water as novel biological detention pond of transition layer, a serial communication port, includes the cell body, from the top down has laid filter layer, geotechnological cloth, the drainage blanket that permeates water in proper order in the cell body, the top reservation of cell body has rainwater detention district, the perforation drain pipe has been laid to the bottom of cell body.

2. A novel bioretention pond using a water permeable geotextile as a transition layer as in claim 1 wherein the filter layer has a thickness of 600 mm.

3. The novel bioretention pond using a water permeable geotextile as a transition layer according to claim 1 wherein the drainage layer is comprised of gravel having a particle size of 3mm to 5 mm.

4. A novel bioretention pond using a water permeable geotextile as a transition layer as in claim 1 wherein the drainage layer has a thickness of 200 mm.

5. The novel bioretention pond using a water permeable geotextile as a transition layer as in claim 1 wherein landscape ornamental plants are planted above the filter layer.

6. A novel bioretention pond using a water permeable geotextile as a transition layer as in claim 1 wherein the perforated drainage pipe has an opening diameter of 3mm and the perforation spacing is 20 mm.

7. A novel bioretention pond according to claim 1 utilizing water permeable geotextiles as a transition layer wherein an overflow tube is provided in the upper side wall of the pond body.