Rainwater garden system for sponge city construction

Abstract

The utility model belongs to the field of sponge city construction, and particularly relates to a rainwater garden system for sponge city construction, a permeation area in a foundation pit of the rainwater garden system sequentially comprises a water storage layer, a covering layer, a planting soil layer, an artificial filler layer, a sand layer and a gravel layer from top to bottom, and the high porosity of water storage ceramsite is utilized, so that the water purification and storage performance is good; through mutual cooperation of all the layers, rainwater is effectively purified and stored, and the water quality and the water storage amount of the rainwater garden system are improved. In addition, the rainwater garden system is simple in structure and convenient to construct and maintain in the later period.

Description

Technical Field

[0001] This application relates to the field of sponge city construction technology, and in particular to a rain garden system for sponge city construction. Background Technology

[0002] Rain gardens are an ecologically sustainable stormwater control and rainwater utilization facility that is frequently used in sponge city design. In improving the urban environment, enhancing quality of life, increasing biodiversity, and creating ecological balance, rain gardens help reduce rainwater-related problems such as urban flooding and water pollution, alleviate pressure on urban pipe networks, and, when integrated with landscaping, create comfortable outdoor spaces.

[0003] With the acceleration of urbanization, traditional rainwater drainage systems are struggling to cope with urban flooding caused by heavy rains, and rainwater resources are not being effectively utilized. Sponge cities enhance the city's ability to absorb and utilize rainwater through measures such as infiltration, retention, storage, purification, utilization, and drainage. Rain gardens, as an important component of sponge cities, play a role in retaining, infiltrating, purifying, and storing rainwater.

[0004] While existing ecological rainwater wetland systems can effectively store and purify water, materials such as gravel and sand have drawbacks such as low porosity, small specific surface area, and poor water retention, resulting in limited water storage and purification effects. Furthermore, they are prone to clogging, aquatic plants are susceptible to dying during the dry season, and maintenance costs are high. Utility Model Content

[0005] This application provides a rain garden system for sponge city construction, which aims to improve water storage and purification effects, and is easy to maintain and construct.

[0006] To achieve the above objectives, this application provides a rain garden system for sponge city construction, comprising a foundation pit, an inlet zone, an infiltration zone, perforated drainage pipes, and an overflow zone; the foundation pit is recessed relative to the ground, the inlet zone and the overflow zone are located on the ground on both sides of the foundation pit, the infiltration zone is located within the foundation pit, and the infiltration zone includes, from top to bottom, a water storage layer, a cover layer, a planting soil layer, an artificial filler layer, a sand layer, and a gravel layer; the perforated drainage pipes are buried in the gravel layer; the highest water level of the water storage layer is lower than that of the inlet zone; the overflow zone is level with the highest water level of the water storage layer; and the cover layer is water-retaining expanded clay granules.

[0007] Optionally, the perimeter of the foundation pit is provided with a slope of no more than 1:3, the water inlet area includes a water guide channel or rainwater pipe located on one side of the foundation pit, and a buffer zone for slowing down the water flow is laid on the slope between the water inlet area and the foundation pit.

[0008] Optionally, the depth of the water storage layer is 200mm-600mm, and the water storage depth is 150mm-550mm.

[0009] Optionally, the thickness of the covering layer is 30mm-50mm, and water-retaining ceramic particles with a particle size of 10mm-20mm are selected.

[0010] Optionally, the thickness of the planting soil layer is 250mm-400mm, and it is a mixture of fine sand, undisturbed soil, fertilizer and water-retaining ceramsite.

[0011] Optionally, the thickness of the artificial filler layer is 300mm-600mm, and it is a mixture of undisturbed soil and water-retaining ceramsite.

[0012] Optionally, the sand layer thickness is 80mm-160mm, and the sand used is construction sand with a particle size of 0.075mm-0.5mm.

[0013] Optionally, the thickness of the gravel layer is 500mm-1000mm, and a mixture of gravel and water-retaining ceramsite is used.

[0014] Optionally, the perforated drainage pipe comprises multiple PVC pipes with an opening ratio of 3%-5%, a pipe diameter of 75mm-150mm, and a pipe spacing of 800mm-1000mm.

[0015] Optionally, the overflow area is an overflow pipe buried on one side of the foundation pit, and the top overflow outlet of the overflow pipe is level with the highest water level of the water storage layer.

[0016] The beneficial effects of the rain garden system for sponge city construction provided in this application are as follows:

[0017] The infiltration zone within the foundation pit of the rain garden system comprises, from top to bottom, a water storage layer, a cover layer, a planting soil layer, an artificial filler layer, a sand layer, and a gravel layer. Utilizing the high porosity, excellent water purification and storage performance, and high compressive strength of the water-retaining expanded clay aggregate, the various layers work together to effectively purify and store rainwater, improving the water quality and water storage capacity of the rain garden system. Furthermore, this rain garden system has a simple structure, facilitating construction and subsequent maintenance. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] in:

[0020] Figure 1 This is a cross-sectional view of a rain garden system for sponge city construction, as shown in one embodiment of this application.

[0021] Explanation of reference numerals in the attached figures:

[0022] 11. Slope; 111. Buffer zone;

[0023] 2. Inlet area;

[0024] 3. Infiltration zone; 31. Water storage layer; 32. Covering layer; 33. Planting soil layer; 34. Artificial filler layer; 35. Sand layer; 36. Gravel layer;

[0025] 4. Perforated drainage pipe;

[0026] 5. Overflow area. Detailed Implementation

[0027] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many other different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0028] It should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0030] Embodiments of this application provide a rain garden system for sponge city construction, which can be used for urban rainwater management, water resource recycling, and ecological environment improvement. For example... Figure 1As shown, the rain garden system includes a foundation pit, an inlet zone 2, an infiltration zone 3, a perforated drainage pipe 4, and an overflow zone 5. The foundation pit is recessed relative to the ground. The inlet zone 2 and the overflow zone 5 are located on the ground on both sides of the foundation pit. The infiltration zone 3 is located inside the foundation pit. From top to bottom, the infiltration zone 3 includes a water storage layer 31, a cover layer 32, a planting soil layer 33, an artificial filler layer 34, a sand layer 35, and a gravel layer 36. The perforated drainage pipe 4 is buried in the gravel layer 36. The highest water level of the water storage layer 31 is lower than that of the inlet zone 2. The overflow zone 5 is level with the highest water level of the water storage layer 31. The cover layer 32 is made of water-retaining expanded clay.

[0031] Understandably, the planting soil layer 33 is used for planting aquatic plants, such as one or more of the following: yellow iris, Dichondra repens, Miscanthus sinensis, Canna indica, Iris, Lythrum salicaria, and Phragmites australis.

[0032] In this embodiment, the infiltration zone 3 within the foundation pit of the rain garden system comprises, from top to bottom, a water storage layer 31, a cover layer 32, a planting soil layer 33, an artificial filler layer 34, a sand layer 35, and a gravel layer 36. Utilizing the high porosity, excellent water purification and storage performance, and high compressive strength of the water-retaining ceramsite, the various layers work together to effectively purify and store rainwater, thereby improving the water quality and water storage capacity of the rain garden system. Furthermore, this rain garden system has a simple structure, facilitating construction and subsequent maintenance.

[0033] In one embodiment, such as Figure 1 As shown, the perimeter of the foundation pit is provided with a slope 11 with a gradient of no more than 1:3. The water inlet area 2 includes a water guide channel or rainwater pipe located on one side of the foundation pit. A buffer zone 111 for slowing down the water flow is laid on the slope 11 between the water inlet area 2 and the foundation pit.

[0034] Specifically, the slope of slope 11 should not exceed 1:3, such as 1:4 or 1:5, preferably 1:3.5. The inlet area 2 is usually formed by a downward-facing trench at the top of slope 11 or by a pre-installed rainwater pipe during the construction of slope 11. The water source is mainly rainwater from nearby rooftops or the ground. The buffer zone 111 can be a mixture of water-retaining ceramsite and pebbles with a length of 300mm-600mm, preferably with a mixing volume ratio of 2:1. The ceramsite should preferably be sintered at 1150℃, with a particle size of 30mm-40mm and a bulk density of 2.14g / cm³. 3 The porosity is 25.1%, the 24-hour volumetric water absorption rate is 35%, the infiltration rate is ≥10mm / min, the barrel pressure is 1.0MPa, the preferred pebble particle size is 50mm-100mm, the buffer zone 111 can reduce the runoff intensity of the inlet zone 2, and at the same time, it can perform preliminary mud blocking and purification of the rainwater in the inlet zone 2.

[0035] In one embodiment, such as Figure 1As shown, the infiltration zone 3 includes, from top to bottom, a water storage layer 31, a cover layer 32, a planting soil layer 33, an artificial filler layer 34, a sand layer 35, and a gravel layer 36.

[0036] Among them, the depth of water storage layer 31 is 200mm-600mm, and the water storage depth is 150mm-550mm.

[0037] The covering layer 32 has a thickness of 30mm-50mm and is made of water-retaining ceramsite with a particle size of 10mm-20mm. Preferably, the covering layer 32 has a thickness of 30mm, and the water-retaining ceramsite is preferably ceramsite sintered at 1050℃, with a particle size of 10mm-20mm and a bulk density of 1.56g / cm³. 3 With a porosity of 38.7%, a 24-hour volumetric water absorption rate of 43.8%, an infiltration rate of ≥15mm / min, and a barrel compressive strength of 0.7MPa, it is mainly used to stabilize the roots, retain water, and allow air to pass through the planted aquatic plants.

[0038] The planting soil layer 33 has a thickness of 250mm-400mm, preferably 300mm. In actual construction, the preferred composition of the planting soil layer 33 is: 50-60 parts by weight of water-retaining ceramsite, 10-20 parts of fine sand, 10-20 parts of undisturbed soil, and 2-8 parts of organic fertilizer. The water-retaining ceramsite is preferably sintered at 950℃, with a particle size of 40mm-50mm and a bulk density of 1.21g / cm³. 3 The porosity is 55.1%, the 24-hour volumetric water absorption rate is 57.8%, the infiltration rate is ≥20mm / min, and the barrel compressive strength is 0.31MPa. During actual construction, the water-retaining expanded clay aggregate and organic fertilizer are mixed evenly in advance according to a specific ratio, allowing the organic fertilizer to better integrate into the pores of the expanded clay aggregate. Before use, it is then mixed evenly with fine sand and undisturbed soil. Using water-retaining expanded clay aggregate in planting soil layer 33 can effectively provide nutrients for aquatic organisms and enhance water filtration and retention performance, thus having a sustained effect on the root growth of aquatic plants in planting soil layer 33.

[0039] The artificial filler layer 34 has a thickness of 300mm-600mm and is made of a mixture of undisturbed soil and water-retaining ceramsite, with a preferred thickness of 500mm. In actual construction, the artificial filler layer 34 can consist of 40-60 parts undisturbed soil and 40-60 parts water-retaining ceramsite. Preferably, it contains 40 parts undisturbed soil and 60 parts ecological ceramsite. The water-retaining ceramsite is preferably ceramsite sintered at 1050℃, with a particle size of 20mm-30mm and a bulk density of 1.46g / cm³. 3The porosity is 47.1%, the 24-hour volumetric water absorption rate is 47.8%, the infiltration rate is ≥20mm / min, and the barrel compressive strength is 0.5MPa. The artificial filler layer 34 has good permeability, which can promote the rapid infiltration of rainwater into the water storage layer 31, reduce the waterlogging effect of the water storage layer 31 during heavy rainfall, and enhance the water storage function of the rain garden during the dry season; it can also provide more soil space for the root growth of plants in the planting soil layer 33.

[0040] The thickness of the sand layer 35 is 80mm-160mm, preferably 100mm. The sand layer 35 mainly serves to isolate the soil layer 33 and the artificial filler layer 34 from mud and sand and faults.

[0041] The gravel layer 36 has a thickness of 500mm-1000mm, preferably 800mm, and mainly consists of a mixture of gravel and water-retaining ceramsite. The gravel content is 40-60 parts, and the ecological ceramsite content is 40-60 parts. Preferably, the gravel content is 60 parts, and the ecological ceramsite content is 40 parts. The gravel particle size is preferably 5mm-20mm, and the ecological ceramsite is preferably ceramsite sintered at 1150℃, with a particle size of 10mm-30mm and a bulk density of 2.51g / cm³. 3 The porosity is 24.6%, the 24-hour volumetric water absorption rate is 28.8%, the infiltration rate is ≥10mm / min, and the barrel compressive strength is 1.1MPa. The gravel layer 36 is made of gravel of different particle sizes and water-retaining ceramsite mixed according to particle size distribution, which can compact the strength of the gravel layer 36. The use of water-retaining ceramsite in the gravel layer 36 can further enhance the water purification and water storage capacity of the sponge city rain garden system.

[0042] In the drainage area, PVC pipes with an opening rate of 3%-5% and a pipe diameter of 75-150mm are selected, preferably 100mm. The opening is set at a downward 45-degree angle, and the top of the pipe is not perforated. The pipes are placed in the gravel layer 36, and the pipe spacing is set at 800-1000mm, preferably 1000mm.

[0043] Among them, overflow zone 5 is an overflow pipe buried on one side of the foundation pit. The top overflow outlet of the overflow pipe is level with the highest water level of the water storage layer 31, which directly discharges the excess rainwater exceeding the water storage capacity of the rain garden into the municipal drainage system or surrounding natural water bodies. Adjustable vertical overflow outlets are preferred.

[0044] In this embodiment, water-retaining ceramsite is used in the buffer zone 111 on the slope 11, the cover layer 32, planting soil layer 33, artificial filler layer 34, and gravel layer 36 in the infiltration zone 3. Due to the porous properties of the water-retaining ceramsite, it can effectively purify rainwater and extend the water storage time. By mixing it with traditional materials used in the construction of traditional sponge city rain gardens (such as pebbles, undisturbed soil, fine sand, gravel, etc.), and adopting the traditional structural construction mode of sponge city rain gardens, the operation and maintenance costs can be further reduced and the ecological and environmental benefits can be improved.

[0045] It should be noted that the water-retaining ceramsite used in the embodiments of this application can be existing water-retaining ceramsite, or it can be manufactured in the following manner to realize the recycling of solid waste resources and reduce environmental pollution.

[0046] Specifically, the water-retaining ceramsite is made by mixing solid waste materials such as sludge from urban sewage treatment plants, fly ash, biomass boiler ash, ceramic factory waste mud, rice husks, and areca nut residue into irregular spherical ceramsite, which is then heat-treated at 950℃-1150℃ for 1.5-2 hours to obtain ceramsite with a particle size range of 10mm-50mm and a bulk density of 1.08g / cm³. 3 -2.51g / cm 3 Porosity 20.7%-60%, 24-hour volumetric water absorption rate 26.3%-57.8%, infiltration rate ≥2mm / min, cylinder compressive strength 0.31MPa-1.1MPa.

[0047] In summary, the rain garden system in this embodiment, through a mixture of water-retaining expanded clay aggregates with undisturbed soil, fine sand, and gravel, is suitable for all three working levels of the infiltration zone, effectively purifying and storing rainwater, thereby improving water quality and storage capacity. Furthermore, the rain garden system of this application has a simple structure and construction process, good practicality, and can effectively reduce operation and maintenance costs, demonstrating significant social, environmental, and economic benefits.

[0048] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A rainwater garden system for sponge city construction, characterized in that, The application relates to a water storage and permeation device, which comprises a foundation pit, a water inlet area, a permeation area, a perforated drainage pipe and an overflow area; the foundation pit is arranged in a recessed mode relative to the ground; the water inlet area and the overflow area are respectively arranged on the ground on two sides of the foundation pit; the permeation area is arranged in the foundation pit; the permeation area comprises, from top to bottom, a water storage layer, a covering layer, a planting soil layer, an artificial filler layer, a sand layer and a gravel layer; the perforated drainage pipe is embedded in the gravel layer; the highest water level of the water storage layer is lower than the water inlet area; the overflow area is flush with the highest water level of the water storage layer; the covering layer is water storage ceramsite. 2.The rainwater garden system for sponge city construction of claim 1, wherein, The periphery of the foundation pit is provided with a side slope with a slope not greater than 1:3; the water inlet area comprises a water guide groove or a rainwater pipe arranged on one side of the foundation pit; and a buffer zone for slowing down water flow velocity is arranged on the side slope between the water inlet area and the foundation pit. 3.The rainwater garden system for sponge city construction of claim 1, wherein, The depth of the water storage layer is 200mm-600mm, and the water storage depth is 150mm-550mm. 4.The rainwater garden system for sponge city construction of claim 1, wherein, The thickness of the covering layer is 30mm-50mm, and the water storage ceramsite with a particle size of 10mm-20mm is selected. 5.The rainwater garden system for sponge city construction of claim 1, wherein, The thickness of the planting soil layer is 250mm-400mm, and the fine sand, undisturbed soil, fertilizer and water storage ceramsite mixture are adopted. 6.The rainwater garden system for sponge city construction of claim 1, wherein, The thickness of the artificial filler layer is 300mm-600mm, and the undisturbed soil and water storage ceramsite mixture are adopted. 7.The rainwater garden system for sponge city construction of claim 1, wherein, The thickness of the sand layer is 80mm-160mm, and the building sand with a particle size of 0.075mm-0.5mm is adopted. 8.The rainwater garden system for sponge city construction of claim 1, wherein, The thickness of the gravel layer is 500mm-1000mm, and the gravel and water storage ceramsite mixture are adopted. 9.The rainwater garden system for sponge city construction of claim 1, wherein, The perforated drainage pipe comprises a plurality of PVC pipes with an opening rate of 3%-5%, a pipe diameter of 75mm-150mm and a pipe spacing of 800mm-1000mm. 10.The rainwater garden system for sponge city construction of claim 1, wherein, The overflow area is an overflow pipe embedded on one side of the foundation pit, and the top overflow port of the overflow pipe is flush with the highest water level of the water storage layer.

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