AU2021105271A4

AU2021105271A4 - Rainwater filtration garden

Info

Publication number: AU2021105271A4
Application number: AU2021105271A
Authority: AU
Inventors: Xinlin HUO; Jianye Li; Maolin LI; Jing Shen; Yan Wang; Xiaoning XUE; Xin Zhao
Original assignee: China Architecture Design and Research Group Co Ltd
Current assignee: China Architecture Design and Research Group Co Ltd
Priority date: 2021-04-13
Filing date: 2021-06-29
Publication date: 2021-10-14
Anticipated expiration: 2029-06-29
Also published as: CN215223342U; WO2022217749A1

Abstract

The application relates to a rainwater filtration garden which comprises: a pit groove formed by 5 excavating an original soil layer, wherein a water storage layer, a water permeable layer and a planting soil layer are sequentially laid in the pit groove from bottom to top, and the top surface of the planting soil layer encloses a concave planting space; a rainwater storage pipe, wherein a water inlet of the rainwater storage pipe is located outside the concave planting space for rainwater to flow in, and a water outlet of the rainwater storage pipe is located inside or outside the concave 10 planting space for guiding rainwater into the concave planting space; an overflow pipe perpendicularly penetrating through the water permeable layer and the planting soil layer, wherein a first end opening of the overflow pipe is located in the concave planting space, and a second end opening of the overflow pipe is located in the water storage layer; and a perforated pipe laid inside the water storage layer and connected with a water use site on the ground through a drain pipe. 15 According to the utility model, the rainwater is well filtered and purified through a plant root system, a root protection layer and a multi-stage permeable layer, the water quality is guaranteed, the filtered rainwater is uniformly discharged for use in the water use sites through the perforated pipes, and the rainwater resource is fully utilized. 1/1 Drawings slope gradient 2% 891O76slope gradient 2% 3 Fig.1I 8 97 ~side slope 3:1 - - 12 5 Fig. 2

Description

1/1

Drawings

slope gradient 2% 891O76slope gradient 2%

3

Fig.1I

8 97

~side slope 3:1

- - 12

Fig. 2

Description

Rainwater Filtration Garden

Technical Field The application belongs to the technical field of rainwater gardens, and particularly relates to a

rainwater filtration garden.

Background Art Since the promulgation of Technical Guidelinesfor Sponge City Construction, the upsurge of

sponge city construction has been raised in China. The ultimate goal of the construction of sponge

city is the effective management of rainwater and flood, and its comprehensive control objectives

include the control of total amount of rainwater, the resource utilization of rainwater, the control of

rainwater pollution and peak reduction, while the realization of the goal depends on the

implementation of low-impact development technology.

Rainwater garden is a common ecological facility in sponge city, which is produced on the basis of

sinking green space form combined with additional biological retention function and landscape

leisure and ornamental functions. The regulation and storage, infiltration and purification are

realized by the vegetation on the surface layer of the rainwater garden, the planting matrix and

microorganisms in the base layer, enabling effective purification treatment on the rainwater; and

the rainwater is regulated and stored according to the space provided by the concave surface and

the pores of the underground gravel layer.

In a common rainwater garden, ground rainwater flows and is filtered through upper vegetation,

with impurities such as leaves, branches, gravel particles and the like mixed in rainwater removed;

and then the next filtration is performed through layer-by-layer infiltration, and the filtered

rainwater directly permeates into the ground. Although the rainwater garden accords with the

concept of the sponge city, due to the simple structure, the rainwater garden is poor in filtering

effect after running for a period of time, which not only reduces the function of filtering and

purifying rainwater, but also causes high difficulty to later maintenance; and a rainwater garden

also discharges preliminarily filtered rainwater into a municipal rainwater pipeline through a

rainwater well, with rainwater resource not fully utilized, which does not meet the construction

concept of the sponge city.

Summary of the Invention In view of the above analysis, the utility model is directed to provide a rainwater filtration garden, which is used for solving the problems that an existing rainwater garden is poor in filtering effect after running for a period of time, and filtered rainwater is directly discharged into a rainwater pipeline, with rainwater resource not fully utilized. The purpose of the utility model is achieved as follows. A rainwater filtration garden comprises: a pit groove formed by excavating an original soil layer, wherein a water storage layer, a water permeable layer and a planting soil layer are sequentially laid in the pit groove from bottom to top, and the top surface of the planting soil layer encloses a concave planting space; a rainwater storage pipe, wherein a water inlet of the rainwater storage pipe is located outside the concave planting space for rainwater to flow in, and a water outlet of the rainwater storage pipe is located inside or outside the concave planting space for guiding rainwater into the concave planting space; an overflow pipe perpendicularly penetrating through the water permeable layer and the planting soil layer; and a first end opening of the overflow pipe is located in the concave planting space, and a second end opening of the overflow pipe is located in the water storage layer; and a perforated pipe laid inside the water storage layer and connected with a water use site on the ground through a drain pipe. Further, the overflow pipe is directly communicated with the perforated pipe. Further, the top surface of the planting soil layer is provided with a planting plane and a side slope, the planting plane is in transition connection with the side slope, and the slope gradient of the side slope is 3:1; and the first end opening is 150-230 mm higher than the planting plane. Further, the perforated pipe is arranged horizontally and 10-50 mm above the bottom surface of the water storage layer. Furthermore, the number of the perforated pipes is at least two, uniformly distributed in the water storage layer. Further, at least one of the overflow pipe, the perforated pipe, and the drain pipe is a PVC pipe. Further, the water storage layer is piled up by gravel of a first particle size, and the water permeable layer is piled up by gravel of a second particle size, the first particle size being larger than the second particle size. Further, the first particle size is 20-40 mm, and the second particle size is 10-20 mm; and the thickness of the water storage layer is 300 mm, the thickness of the water permeable layer is 80 mm, and the thickness of the planting soil layer is 150-300 mm. Furthermore, permeable geotextiles are wrapped around the water storage layer and the water permeable layer. Further, the permeable geotextiles are wrapped around the perforated pipe; and anti-seepage geotextiles are laid on the bottom wall and the side wall of the pit groove. Further, the first end opening of the overflow pipe is provided with an anti-backflow assembly. Compared with the prior art, the utility model has at least one of the following beneficial effects. (1) The rainwater is filtered and purified through a plant root system, a root protection layer and a multi-stage water permeable layer, the filtering effect is good, the water quality is guaranteed, and the filtered rainwater is stored in the water storage layer; and the filtered rainwater is uniformly discharged for use in the water use sites through the perforated pipes laid in the water storage layer, and the rainwater resource is fully utilized. (2) Anti-seepage geotextiles are laid on the bottom wall and the side wall of the pit groove for preventing rainwater seepage and improving rainwater collection efficiency. (3) The permeable geotextiles are wrapped around the perforated pipe, so that the perforation can be effectively prevented from being blocked by soil particles, and the working reliability of the perforated pipe is guaranteed. (4) The water permeable layer and the water storage layer are wrapped into a square structure by using the geotextiles, enabling a convenient construction; meanwhile, soil can be prevented from permeating into the water permeable layer and gaps among gravel of the water storage layer to affect porosity and permeability of the gravel layer; and it can also guarantee stability of the garden stratum structure. (5) A vent cap is arranged at the first end opening of the overflow pipe and has an impurity filtering function, so that impurities can be prevented from entering the overflow pipe to cause blockage, and the problem of blockage of the overflow pipe is solved. (6) The utility model has the advantages of simple structure, convenient construction, low cost, and good water quality treatment effect through a refined structure. It also can be used for rural dispersed small-sized sewage treatment and has wide application prospect.

Brief Description of the Drawings In order to more clearly describe the technical solutions in the embodiments of the present description or the prior art, the following will briefly introduce the drawings to be used in the description of the embodiments or the prior art. It will be apparent to those skilled in the art that the drawings in the following description are only some of the embodiments described in the present description, and that other drawings may be obtained from the drawings. Fig. 1 is a schematic cross-sectional view of a rainwater filtration garden of the present utility model; and Fig. 2 is a top view of the rainwater filtration garden of the present utility model. Reference numerals:

1-original soil layer; 2-water storage layer; 3-water permeable layer; 4-planting soil layer; 5-anti-seepage geotextile; 6-root protection layer; 7-overflow pipe; 8-rainwater storage pipe; 9-energy dissipation mechanism; 10-plant; 11-perforated pipe; and 12-drain pipe.

Detailed Description of the Invention In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without involving any inventive effort are within the scope of protection of the present application. To facilitate an understanding of the embodiments of the present application, reference will now be made to the following descriptions of specific embodiments, which are not to be construed as limiting the embodiments of the present application, taken in conjunction with the accompanying drawings. One specific embodiment of the utility model, as shown in Figs. 1 and 2, discloses a rainwater filtration garden, comprising: a pit groove formed by excavating an original soil layer 1, wherein a water storage layer 2, a water permeable layer 3 and a planting soil layer 4 are sequentially laid in the pit groove from bottom to top, the water permeability of the planting soil layer 4, the water permeable layer 3 and the water storage layer 2 are sequentially enhanced, and the top surface of the planting soil layer 4 encloses a concave planting space; a rainwater storage pipe 8 configured for introducing rainwater into the concave planting space, wherein a water inlet of the rainwater storage pipe 8 is located outside the concave planting space for rainwater to flow in; and a water outlet of the rainwater storage pipe 8 is located inside or outside the concave planting space for guiding rainwater into the concave planting space; and an overflow pipe 7 penetrating through the water permeable layer 3 and the planting soil layer 4, wherein the overflow pipe 7 is arranged perpendicularly to the horizontal plane, and both ends of the overflow pipe 7 are respectively provided with a first end opening and a second end opening; and the first end opening is located in the concave planting space, and the second end opening is located in the water storage layer 2; and a perforated pipe 11 laid inside the water storage layer 2 and connected with a drain pipe 12, wherein the drain pipe 12 is connected with a water use site on the ground.

In the embodiment, the top surface of the planting soil layer 4 is provided with a planting plane and a side slope, the planting plane is in transition connection with the side slope, and the slope gradient of the side slope is 3:1. The required depth can be quickly and advantageously achieved, and the problem of concave safety of the rainwater garden is solved. In the embodiment, the overflow pipe 7 is used as a rainwater collection pipeline, and the first end opening of the overflow pipe 7 is 150-230 mm higher than the planting soil layer 4; the first end opening is used as an overflow port, and a small amount of rainwater directly falls into the first end opening of the overflow pipe 7 and enters the water storage layer; as the rain continues, the water level continues to rise; and when the rainwater is higher than the first end opening, the rainwater enters the water storage layer through the overflow pipe 7 to realize the overflow function. In consideration of the fact of the rainwater flowing backwards, the rainwater entering the water storage layer 2 through the overflow pipe 7 may pollute the filtered rainwater in the water storage layer 2; the overflow pipe 7 is directly communicated with the perforated pipe 11, and as the overflow pipe 7 is directly communicated with the perforated pipe 11, once the water level in the concave planting space exceeds the first end opening of the overflow pipe 7, the rainwater is directly discharged out through the perforated pipe when the rainwater flows backwards. and unfiltered rainwater is reduced to enter the water storage layer as much as possible, and pollution to the water storage layer is decreased. According to an alternative embodiment, the anti-seepage geotextiles 5 are laid on the bottom wall and the side wall of the pit groove in consideration of rainwater infiltration and lateral infiltration, so that rainwater seepage is prevented by laying the anti-seepage geotextiles 5, and rainwater collection efficiency is improved. In order to prevent the perforation of the perforated pipe 11 from being blocked, the permeable geotextiles are wrapped around the perforated pipe 11, so that the perforation can be effectively prevented from being blocked by soil particles, and the working reliability of the perforated pipe 11 is guaranteed. Further, a perforated pipe 11 is horizontally arranged, and 10-50 mm above the bottom surface of the water storage layer 2; the number of the perforated pipes 11 is at least two, uniformly distributed in the water storage layer 2; and the perforated pipe 11 is provided with at least one water outlet connected with a drain pipe 12, and the drainage capacity can be improved by arranging a plurality of perforated pipes 11. In this embodiment, the water storage layer 2 is piled up by gravel of a first particle size, and the water permeable layer 3 is piled up by gravel of a second particle size, the first particle size being larger than the second particle size.

Further, the number of the water permeable layers 3 is a plurality of layers. From top to bottom, the permeability of the water permeable layers increases sequentially, the particle size of the gravel increases gradually, and the thickness of the water permeable layers increases sequentially. Further, the first particle size is 20-40 mm, and the second particle size is 10-20 mm; the thickness of the water storage layer 2 is 300 mm, the thickness of the water permeable layer 3 is 80 mm, and the thickness of the planting soil layer 4, that is, the distance from the planting plane to the top surface of the water permeable layer 3, is 150-300 mm. In a preferred embodiment of this embodiment, permeable geotextiles are wrapped around the water storage layer 2 and the water permeable layer 3. During construction, the gravel is sieved according to the first particle size and the second particle size; the gravel with the first particle size is wrapped into the water storage layer 2 by the permeable geotextiles, the gravel with the second particle size is wrapped into the permeable layer 3, and the gravel is wrapped by the permeable geotextiles, so that the gravel can maintain a stable shape conveniently and can be laid conveniently. By the aid of the permeable geotextiles, small soil particles can be filtered, soil is prevented from being filled in gaps of the water permeable layer 3 and the water storage layer 2, and permeation and water outlet functions are guaranteed. In the embodiment, a root protection layer 6 is laid on the top surface of the planting soil layer 4, so that the loss of surface soil is avoided. Optionally, a vent cap is arranged at the first end opening of the overflow pipe 7 and has an impurity filtering function, so that floating impurities are prevented from entering the overflow pipe 7 to cause blockage, and overflow reliability is guaranteed. Optionally, the first end opening of the overflow pipe 7 is provided with an anti-backflow assembly in the form of a floating sleeve. Specifically, the first end opening of the overflow pipe 7 is sleeved with an extension pipe in a sliding mode, the inner wall of the extension pipe is in sealing contact with the outer wall of the overflow pipe 7, and the extension pipe can partially overlap with the overflow pipe 7; annular foam is arranged outside the extension pipe, and the inner diameter of the annular foam is equal to the outer diameter of the extension pipe; and the outer diameter of the annular foam is equal to 2-3 times the outer diameter of the extension pipe, and the length of the overlapping portion of the extension pipe and the overflow pipe 7 ranges from 50 mm to 100 mm. When the rainwater is too large, the extension pipe can float under the buoyancy effect of the annular foam, and the annular foam drives the extension pipe to move upwards; the height of the water inlet of the overflow pipe 7 can be properly increased, with a maximum increased height of about 100mm, so that the rainwater can be prevented from flowing backwards into the overflow pipe 7 to a certain extent. When the water level is too high to exceed the maximum overflow water level of the overflow pipe 7, rainwater enters the water storage layer through the first end opening to realize an overflow drainage function. When the water level decreases, the extension tube decreases until it is reset. By arranging the anti-backflow assembly, the height of the overflow pipe 7 exposed out of the ground can be reduced, the appearance is more attractive, and the defect that the overflow pipe is easy to bend and damage due to overlarge length is reduced. In the embodiment, the water outlet of the rainwater storage pipe 8 is located at the top of the side slope, and an energy dissipation mechanism 9 is laid in the water falling range of the water outlet so as to prevent scouring. Optionally, the energy dissipation mechanism 9 is piled up by gravel, the sources of the gravel are wide, the cost is low, and the garden side slope can be more attractive by pattern piling arrangement of the gravel. Further, at least one of the overflow pipe 7, the perforated pipe 11, and the drain pipe 12 is a PVC pipe. The PVC pipe has excellent tensile strength, compressive strength and corrosion resistance, and is wide in source and low in cost. When rainfall occurs, rainwater directly falls into the concave planting space, or enters the concave planting space through the rainwater storage pipe 8; the rainwater flowing out of the rainwater storage pipe 8 flows to the periphery or downwards to permeate after being dissipated by cobblestones; a planting soil layer for planting plants 10 absorbs certain water; and after the water content of the planting soil layer is saturated, the rainwater permeates downwards and through the permeable geotextiles. The rainwater is purified by filtering and intercepting from the middle crushed stone water permeable layer 3 and the water storage layer 2. Along with the infiltration of rainwater, when the water level of the rainwater in the water storage layer is higher than that of the perforated pipe 11, the rainwater is collected in the perforated pipe 11 through the perforation and finally discharged to a water use site through the drain pipe 12 for recycling. When the rainfall is large and exceeds the infiltration capacity of the rainwater garden, the rainwater is accumulated on the surface of the concave planting space. When the water level in the concave planting space is higher than the first end opening of the overflow pipe 7, the rainwater enters the overflow pipe, the rainwater is directly discharged through the perforated pipe 11, and unfiltered rainwater is reduced to enter the water storage layer as much as possible, so that the pollution to the water storage layer is decreased. Compared with the prior art, the rainwater filtration garden provided by the embodiment has at least the following beneficial effects. (1) The rainwater is filtered and purified through a plant root system, a root protection layer and a multi-stage water permeable layer, the filtering effect is good, the water quality is guaranteed, and the filtered rainwater is stored in the water storage layer; and the filtered rainwater is uniformly discharged for use in the water use sites through the perforated pipes laid in the water storage layer, and the rainwater resource is fully utilized. (2) Anti-seepage geotextiles are laid on the bottom wall and the side wall of the pit groove for preventing rainwater seepage and improving rainwater collection efficiency. (3) The permeable geotextiles are wrapped around the perforated pipe, so that the perforation can be effectively prevented from being blocked by soil particles, and the working reliability of the perforated pipe is guaranteed. (4) The water permeable layer and the water storage layer are wrapped into a square structure by using the geotextiles, enabling a convenient construction; meanwhile, soil can be prevented from permeating into the water permeable layer and gaps among gravel of the water storage layer to affect porosity and permeability of the gravel layer; and it can also guarantee stability of the garden stratum structure. (5) A vent cap is arranged at the first end opening of the overflow pipe and has an impurity filtering function, so that impurities can be prevented from entering the overflow pipe to cause blockage, and the problem of blockage of the overflow pipe is solved. (6) The water outlet of the rainwater storage pipe is located at the top of the side slope, the energy dissipation mechanism is laid in the water falling range of the water outlet, and the energy dissipation mechanism is piled up by gravel, so that scouring can be prevented, and the garden side slope can be more beautiful by piling and arranging the gravel in a pattern. (7) With the side slope having the ratio of 3:1, the required depth can be quickly and advantageously achieved, and the problem of concave safety of the rainwater garden is solved. (8) The utility model has the advantages of simple structure, convenient construction, low cost, and good water quality treatment effect through a refined structure. It also can be used for rural dispersed small-sized sewage treatment and has wide application prospect. The specific implementations described above further describe the purpose, technical solutions, and beneficial effects of the present application in further detail. It should be understood that the above descriptions are only specific implementations of the application, and are not used to limit the protection scope of the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. A rainwater filtration garden, comprising: a pit groove formed by excavating an original soil layer (1), wherein a water storage layer (2), a water permeable layer (3) and a planting soil layer (4) are sequentially laid in the pit groove from bottom to top, and a top surface of the planting soil layer (4) encloses a concave planting space; a rainwater storage pipe (8), wherein a water inlet of the rainwater storage pipe (8) is located outside the concave planting space for rainwater to flow in, and a water outlet of the rainwater storage pipe (8) is located inside or outside the concave planting space for guiding rainwater into the concave planting space; an overflow pipe (7) perpendicularly penetrating through the water permeable layer (3) and the planting soil layer (4); and a first end opening of the overflow pipe (7) is located in the concave planting space, and a second end opening of the overflow pipe (7) is located in the water storage layer (2); and a perforated pipe (11) laid inside the water storage layer (2) and connected with a water use site on the ground through a drain pipe (12).

2. The rainwater filtration garden according to claim 1, wherein the overflow pipe (7) is directly communicated with the perforated pipe (11).

3. The rainwater filtration garden according to claim 1, wherein the top surface of the planting soil layer (4) is provided with a planting plane and a side slope, the planting plane is in transition connection with the side slope, and the slope gradient of the side slope is 3:1; and the first end opening is 150-230 mm higher than the planting plane.

4. The rainwater filtration garden according to claim 3, wherein the perforated pipe (11) is arranged horizontally and 10-50 mm above the bottom surface of the water storage layer (2).

5. The rainwater filtration garden according to claim 4, wherein the number of the perforated pipes (11) is at least two, uniformly distributed in the water storage layer (2).

6. The rainwater filtration garden according to claim 5, wherein at least one of the overflow pipe (7), the perforated pipe (11), and the drain pipe (12) is a PVC pipe.

7. The rainwater filtration garden according to any one of claims 1 to 6, wherein the water storage layer (2) is piled up by gravel of a first particle size, and the water permeable layer (3) is piled up by gravel of a second particle size, the first particle size being larger than the second particle size.

8. The rainwater filtration garden according to claim 7, wherein the first particle size is 20-40 mm, and the second particle size is 10-20 mm; and the thickness of the water storage layer (2) is 300 mm, the thickness of the water permeable layer

(3) is 80 mm, and the thickness of the planting soil layer (4) is 150-300 mm.

9. The rainwater filtration garden according to claim 8, wherein permeable geotextiles are wrapped around the water storage layer (2) and the water permeable layer (3).

10. The rainwater filtration garden according to claim 1, wherein the permeable geotextiles are wrapped around the perforated pipe (11).