CN210194861U

CN210194861U - Hexagonal building group system with rain collection greening function

Info

Publication number: CN210194861U
Application number: CN201920051904.5U
Authority: CN
Inventors: Zheming Zhuang; 庄哲明; Wei Lyu; 吕玮; Tiancheng Han; 韩天成; Tao Zhu; 朱涛; Hanjie Ren; 任汉杰
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2019-01-11
Filing date: 2019-01-11
Publication date: 2020-03-27
Anticipated expiration: 2029-01-11

Abstract

The utility model discloses a hexagonal building group system with rain-collecting greening function, which comprises a plurality of groups of building groups, rain-collecting greening impounding reservoirs and a central underground impounding reservoir, wherein a building is formed by regular hexagonal basic materials, a solar photovoltaic panel is installed at the top end of the building, and the utilization rate of solar energy is improved by modifying the regular hexagon; and the hexagonal building effectively improves the rainwater collection efficiency, reasonably develops and utilizes the collected rainwater, and realizes the ingenious combination of solar energy utilization in sunny days and rainwater collection in rainy days.

Description

Hexagonal building group system with rain collection greening function

Technical Field

The utility model belongs to the technical field of the building, concretely relates to hexagon building crowd system with collection rain afforestation function.

Background

In recent years, with frequent extreme weather, part of cities are frequently attacked by strong rainstorm, and with the forward progress of urbanization, the land is gradually replaced by cement, so that the infiltration of rainwater is reduced, and the urban waterlogging is caused by the influence of extreme weather. In cities with inland inundation, the maximum depth of ponding exceeds 50cm and accounts for 74.6%, and the maximum depth of ponding exceeds 15cm and reaches 90%. Moreover, the current rainwater collection means for building buildings in cities are relatively deficient, the utilization rate is low, and the utilization mode is single and low in efficiency. On the other hand, the problem of water shortage in cities in China is more and more serious. The water consumption of China is about 63545 billion cubic meters in one year, and if rainwater resources can be utilized, the problem of water shortage can be greatly relieved. Meanwhile, water resource pollution in China is serious, and rainwater formed by plant transpiration and evaporation is relatively clean. How to collect rainwater quickly and effectively, reduce urban waterlogging and how to utilize the rainwater is a problem to be solved urgently at present.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects of the prior art and provide a hexagonal building group system with rain collecting and greening functions, a building made of regular hexagonal basic materials is adopted, a solar photovoltaic panel is installed at the top end of the building, and the utilization rate of solar energy is improved by modifying the regular hexagon; and the hexagonal building effectively improves the rainwater collection efficiency, reasonably develops and utilizes the collected rainwater, and realizes the ingenious combination of solar energy utilization in sunny days and rainwater collection in rainy days.

The utility model discloses a realize through following technical scheme:

a hexagonal building group system with rain-collecting greening function comprises a plurality of groups of building groups, rain-collecting greening reservoirs and central underground reservoirs;

the building group is formed by jointing and connecting 3-5 buildings with the same cross section shape and regular hexagon cross section by adjacent sides, the building group is arranged on a concentric circle, the opening of the C-shaped structure points to the circle center, a rain-collecting greening reservoir is arranged at the opening of the building group and critically arranged with the building, a central underground reservoir is arranged at the circle center formed by the building group, and the rain-collecting greening reservoir is connected with the central underground reservoir through an overflow pipe; and arranging a comprehensive water using area on the ground vertically above the central underground reservoir.

In the technical scheme, the rainwater collection greening reservoir comprises a water storage layer, a covering layer, a planting soil layer, a sand layer and a gravel layer from top to bottom respectively.

In the above technical solution, a perforated pipe is disposed in the gravel layer.

In the technical scheme, the comprehensive water consumption area adopts the water suction pump to pump water in the central underground water storage tank to the ground to be connected with water utilization devices such as public toilets, fire-fighting emergency water sources and self-service car washing devices.

In the technical scheme, the building adopts an assembly type building structure, namely, a structure system and various functional skins are refined into modules of different types, each module can be subjected to industrial standardized production, a user can select the modules to construct units according to the requirement, and the units are transversely juxtaposed and longitudinally superposed to form the whole building.

In the above technical solution, the upper surface of the building is covered with a photovoltaic device.

In the technical scheme, the photovoltaic device adopts N-TiO₂A photovoltaic panel made of a dye-sensitized solar material.

In the technical scheme, low-power induction lighting equipment or ever-burning equipment (such as corridor lamps, emergency lamps and the like) is arranged in the building and connected with the photovoltaic device.

In the technical scheme, a water collecting tank is arranged at the roof of the building, a drainage water pipe is arranged on the inner side wall body of the building group and is connected with the water collecting tank, and rainwater in the water collecting tank is collected into a rainwater collection greening water storage tank through the drainage water pipe.

In the technical scheme, a rainwater filtering device is arranged at the inlet of the rainwater through the reservoir and used for removing impurities in the rainwater and adjusting the pH value of the rainwater.

The utility model discloses an advantage and beneficial effect do:

1. the building group adopts regular hexagons as basic shapes, and based on the design of honeycomb, compared with a square, the building group obtains a larger sunlight absorption area under the condition of equal consumption, thereby saving the cost.

2. The top of the building creatively adopts the hexagon as the bottom plate of the solar light panel, and has higher solar energy collection efficiency compared with the old-style rectangular panel.

3. The groove formed by hexagonal edges is adopted in the building water flow channel structure, and rainwater can be collected more fully through multi-angle multi-level accumulation.

4. The rainwater collection greening system is used for increasing the infiltration time and the infiltration capacity of rainwater through short-term retention and infiltration of rainwater, reducing the flow rate of rainwater runoff, reducing the pressure of rainwater on drainage pipelines, simultaneously increasing the water content of a foundation and supplementing increasingly exhausted underground water.

5. Because the building can be suitable for common civil living, the application after rainwater is collected is more extensive and convenient, and various living services with relatively low requirements on water quality can be provided.

Drawings

Fig. 1 is a schematic view of the three-dimensional structure of the present invention.

Fig. 2 is a schematic view of the top plan structure of the present invention.

Fig. 3 is a schematic view of the structure of the underground part of the present invention.

Fig. 4 is a partial structure schematic diagram of a rain-collecting greening reservoir.

Fig. 5 is a line graph of the actual precipitation amount and the rainwater collection amount.

Fig. 6 is a line graph of rain collection efficiency versus α correction factor.

Wherein: 1 is a building, 2 is a rain-collecting greening reservoir, 2-1 is a water storage layer, 2-2 is a covering layer, 2-3 is a planting soil layer, 2-4 is a sand layer, 2-5 is a gravel layer, 2-6 is a perforated pipe, 3 is a central underground reservoir, 4 is a comprehensive water-using area, and 5 is an overflow pipe.

For a person skilled in the art, other relevant figures can be obtained from the above figures without inventive effort.

Detailed Description

In order to make the technical field person understand the solution of the present invention better, the technical solution of the present invention is further described below with reference to the specific embodiments.

Example 1

As shown in fig. 1-4, a hexagonal building group system with rain-collecting greening function comprises a plurality of groups of building groups, rain-collecting greening reservoirs 2 and central underground reservoirs 3;

the building group is formed by jointing and connecting 3-5 buildings 1 with the same cross section shape and regular hexagon cross section by adjacent sides, the building group is arranged on a concentric circle, the opening of the C-shaped structure points to the circle center, a rain-collecting greening reservoir is arranged at the opening of the building group and is critically arranged with the building, a central underground reservoir is arranged at the circle center formed by the building group, and the rain-collecting greening reservoir is connected with the central underground reservoir through an overflow pipe 5; a comprehensive water usage area 4 is provided at the ground vertically above the central underground reservoir.

The rainwater collection greening reservoir comprises a water storage layer 2-1, a covering layer 2-2, a planting soil layer 2-3, a sand layer 2-4 and a gravel layer 2-5 from top to bottom.

Perforated pipes 2-6 are arranged in the gravel layer.

The comprehensive water consumption area adopts a water suction pump to pump water in the central underground water storage tank to the ground to be connected with water utilization devices such as public toilets, fire-fighting emergency water sources and self-service car washing devices.

The building adopts the assembled building structure, is to be about structural system and various function epidermis refines into the module of different grade type, and every kind of module can both carry out the industrial standardized production, and the user can select for use the module to carry out the framework of unit by oneself according to the demand, and the horizontal juxtaposition of rethread unit, vertical stack generates whole building.

The upper surface of the building is covered with a photovoltaic device.

The photovoltaic device adopts N-TiO₂A photovoltaic panel made of a dye-sensitized solar material.

The building is internally provided with low-power induction lighting equipment or long-term lighting equipment (such as corridor lamps, emergency lamps and the like) connected with the photovoltaic device.

The roof of the building is provided with a water collecting tank, the inner side wall of the building group is provided with a drainage water pipe, the drainage water pipe is connected with the water collecting tank, and rainwater in the water collecting tank is collected into a rainwater collection greening storage tank through the drainage water pipe.

And a rainwater filtering device is arranged at the inlet of the rainwater through the reservoir and is used for removing impurities in the rainwater and adjusting the pH value.

Example 2

Hexagonal assembled building

The basic unit architecture mode is a steel structure frame and skin filling with different functions. The structural system and various functional skins are refined into modules of different types, and each module can be industrially and standardizedly produced. The user can select the module to carry out the unit architecture according to the requirement. And the whole building volume is generated by transversely juxtaposing and longitudinally superposing the units. See patent No. 2017106531050, a modular intelligent heat-insulating roof, and patent No. 2017110136209, a hexagonal assembly building structure for more detailed structure and function of cover hexagonal assembly building.

When assembling the building, the basic modules are transversely spliced and longitudinally overlapped, and a plurality of structural modules are constructed by metalThe pieces are connected to form the whole building. Building top edge sets up the water catch bowl of the baffle of take the altitude and the certain degree of depth, and the rainwater that the guide roof was collected flows in the collecting pipe. The solar conductive glass with the hexagonal frame structure is erected on a roof unit, on one hand, the product can be used for generating electricity through natural light, namely the electricity is generated and used, so that partial electricity utilization requirements of buildings are met, and the photovoltaic panel adopts N-TiO₂The photovoltaic panel made of the dye-sensitized solar material can realize full coverage of roof lighting. And the natural light is used for generating electricity, so that partial electricity utilization requirements of the building are met.

Second, assembly of solar cell

Soaking the conductive glass with a cleaning agent, cleaning the conductive glass for 30min with an ultrasonic cleaner, taking out the conductive glass, washing the conductive glass with deionized water to ensure complete washing, and then sequentially carrying out ultrasonic cleaning twice with deionized water and one time with ethanol for 30min each time. Taking out the glass and drying, placing the glass in a watch glass with the conductive surface facing upwards, and then adding TiCl₄Treating the solution at 70 deg.C for 30min, washing with ethanol, and blow-drying.

Sensitized TiO prepared by screen printing method₂Porous thin-film electrodes, I^3-/I^-As redox electrolyte for dye-sensitized solar cell, the redox electrolyte is prepared from TiO and its diameter₂The puncher matched with the film is used for punching the plastic film, and the punched film is stuck on the TiO2 film to ensure that the holes of the plastic film and the TiO₂The films are exactly coincident. Injecting electrolyte onto the dye-adsorbed TiO2 film with a syringe to form a platinum counter electrode and dye-adsorbed TiO₂The electrodes were clamped with a clamp to complete the cell assembly, with the TiO2 thin film electrode as the working electrode and the platinum electrode as the counter electrode.

Rain-collecting greening reservoir

1. Structure of rain collection afforestation cistern: rain collection greening system's structure mainly has 5 layers, from top to bottom is respectively: water storage layer, covering layer, planting soil layer, artificial packing layer and gravel layer. The cross section is designed to be trapezoidal. Therefore, the boundary of the rain collecting greening system is gentle, the visual landscape effect is ensured, and the slope of about 40 degrees can be more gently connected with the microtopography at the bottom of the garden. 2-3 open ditch drainage water inlets are arranged in each garden, and pebbles are paved at the bottoms of the water inlets to prevent water and soil loss caused by rainwater erosion, so that the water impact force is weakened.

The required materials are as follows: gabions, granite water guide ports, gravels, pebbles, landscape stones, anticorrosion wood and the like.

Selecting plants: yellow flag, loosestrife, bamboo leaf, pennisetum, iris, miscanthus sinensis, festuca arundinacea and the like.

The gabion is selected as the main material of the boundary of the rain collecting greening system for three reasons:

1) is economical and environment-friendly. Waste stone is used as an internal filling material;

2) permeability and filterability. The gap in the gabion is favorable for rainwater to enter the rainwater collecting greening system and simultaneously for initial rainwater

The water has good filtering effect;

3) after a certain amount of soil impurities are accumulated in the stone cracks, plants can naturally grow, and the ecological effect and the landscape effect are both good.

2. The function of collection rain afforestation cistern: rain collecting greening systems can be divided into 2 types according to their functions, with the purpose of saving water resources (impounding water) and with the purpose of reducing carbon emissions (greening). The rainwater collection greening system increases the infiltration time and the infiltration capacity of rainwater through short-term detention and infiltration of rainwater, can increase the water content of foundation, supplements the groundwater that exhausts day by day, simultaneously the water-resistant plant in the conservation cistern, and surplus rivers flow to large-scale cistern for use. On the other hand, in the process of infiltration, the rain-collecting greening system can effectively absorb pollutants in rainwater and purify the water body, so that the purified rainwater can be utilized in more ways, dense green plants can also absorb carbon dioxide in residential areas, carbon emission is reduced, and the air quality of the areas is improved. Under the condition of not considering the drainage of a hidden pipe in a water tank, analysis and calculation show that when the ratio of the urban planning area to the water-tight area in the Beijing urban area is 1, the concave depth of the concave green land is 150mm, and the average concave depth of the concave green land is 1.55 x 10 per year⁸m3 conversion of rainwater to soil water, 3.66 x 10⁸m³The rainwater supplies underground water, and the overflow amount is only 0.11 x 10⁸m³。

Integration of water collecting unit

1. Pipe design

A circle of pipeline is designed at the top of a building to facilitate rainwater gathering and collection, the pipeline is designed into an inclined chute with an inclined angle and inclined towards the center, and a groove-shaped pipeline is arranged at the bottom of the inclined chute, so that rainwater flows down from the inclined chute, enters the groove-shaped pipeline and flows down along the pipeline of a wall body. 2-3 open ditch drainage water inlets are arranged at the lower end, and pebbles are paved at the bottoms of the water inlets to weaken the water flow impulse force. The water storage tank is provided with a hidden pipe at a proper height, a part of rainwater is reserved for greening, and the rest of rainwater is led to the central node through the hidden pipe. The filter screen is arranged in the concealed pipe to preliminarily improve the water quality and reach the basic use standard.

2. Node utilization

The node is a large underground reservoir, and a small water pump is used above the reservoir to pump the stored rainwater to the ground. An integrated water station is built around the water pump, services such as self-service vehicle washing, fire-fighting emergency water sources and the like are provided, and the life quality of surrounding residents is improved.

Example 3

The operation of a hexagonal building group system with rain collecting and greening functions comprises the following steps:

scenario one: rainy day

First, preliminary collecting process

The rainwater falling to the roof is collected by the roof water collecting tank and flows into a drainage water pipe fixed on the building body at the center of the building. Then, the rainwater flows into the central rainwater collecting greening pool. Meanwhile, a part of rainwater directly falls into the rainwater collecting greening pool. This allows the rain water to be collected primarily in the green pool.

Second, transfer process

After the rainwater is preliminarily collected on the water storage layer in the rainwater collecting and greening pool, the rainwater reaches the covering layer and the planting soil layer. The rainwater is primarily purified in the layer, and the demand of the plants on the water is met. The rainwater is then filtered again in the sand and gravel layers and finally collected into a central underground reservoir via a perforated concealed pipe arranged at the bottom.

Third, final collection and use process

After the rainwater is treated by the advanced filtering device at the inlet of the water storage tank, impurities in the rainwater are basically filtered, the pH value reaches the ordinary use level, and the rainwater flows into the water storage tank to be stored. The water pump is arranged on the ground above the reservoir, and water in the reservoir is pumped out through the water pipe for residents, firefighters and the like. Meanwhile, in order to ensure the water quality of the water, a water quality detection and treatment device is added into the reservoir, and when the water quality is reduced to a certain degree, the stored water can be automatically used for greening irrigation in time before the next water storage.

And (4) rainwater collection calculation, namely calculating the rainwater collection volume by using formulas (1) to (5).

V₁＝S₁h......(2)

V₂＝S₂h......(4)

V＝α×n×(4V₁+V₂)......(5)

Sign in meter-rain collection calculation and significance thereof

Letters	Means for	Letters	Means for
				S₁	The single building roof hasEffective area for collecting rain	α	Building side length/rain-collecting greening pool side length
S₂	Effective rain collecting area of single rain collecting greening pool	h	Precipitation amount
				V₁	Rainwater collecting volume of single-building roof	V₂	Rainwater collecting volume of single rainwater collecting greening pool
V	Total volume of collected rainwater	α	Correction factor
				θ	The angle between the rain and the ground	H	Building height
n	Number of building units

Description of the drawings:

1. in the calculation analysis of rainwater collection, the theoretical model is simplified, and the wind direction is specified to be over against the opening of the building group.

The correction factor 2, α is an estimated value, which is related to the plant species in the rain-collecting greening pool, the evaporation capacity of water, the temperature and other factors, and also takes the infiltration loss into consideration.

China has wide breadth, great difference of weather conditions in south and north, great difference of rainfall capacity and rainfall characteristics. All places should reasonably determine the rainwater utilization scheme and scale on the basis of carefully investigating and analyzing natural conditions such as local rainfall characteristics and the like and on the basis of technical-economic comparison, and practically improve the operation efficiency and economic benefit of a rainwater utilization system.

In a large amount of experimental data, we have used several groups of representative data to perform further analysis, calculate the collection efficiency of the device, and finally estimate α with a correction factor of about 0.7, taking into account temperature, wind speed, etc.

Data table for rainfall of four cities of Beijing, Tianjin, Xian and Shanghai in 2017

And meanwhile, the annual precipitation of the four regions 2013 and 2017 in the table is plotted by using MATLAB to obtain an annual precipitation prediction trend chart. Only by taking the sea as an example, according to the MATLAB prediction chart, the rainfall which can be collected in 2019 all the year can reach 5000 tons. The water consumption for washing the car is calculated, 150L of water which needs to be consumed for washing the car every time is taken as reference, and the collected and treated rainwater can provide more than 3 ten thousand car washing services all the year around in 2019. Assuming that each vehicle requires 24 washes per year on average, the scheme may provide a car wash service for 1300 cars.

Scenario two: in sunny days

The conductive glass installed on the roof generates electricity through sunlight, and is connected with low-power induction lighting equipment and long-term lighting equipment (such as corridor lamps, emergency lamps and the like) through electric wires, so that generated energy is reasonably utilized, and electric energy of public facilities is saved.

And (4) calculating the solar energy part, namely calculating the solar energy conversion efficiency by using the following formulas (1) to (4).

V_oc＝|V_fb-V_red|......(1)

η(λ)＝LHE×φ_inj×φ_coli......(4)

Symbol in table three solar energy calculation and meaning thereof

Letters	Means for	Letters	Means for
				V_oc	Open circuit voltage	V_fb	Flat band potential of semiconductor
V_red	Potential difference of redox couple	FF	Fill factor
				I_opt	Maximum workSpecific current	V_opt	Maximum power voltage
I_sc	Short circuit current	η	Photoelectric conversion efficiency
				P_m	Maximum output power	P_in	Incident power
η(λ)	Efficiency of monochromatic light conversion	λ	Monochromatic light wavelength
				LHE	Efficiency of light capture	Φ_inj	Injection quantum efficiency of electrons
Φ_coli	Collection efficiency of electrons

Performance conclusion of titanium dioxide dye-sensitized solar cell doped with ammonia and urea double nitrogen sources:

when the doping level of ammonia is optimal, urea is introduced as a second nitrogen source. The ammonia doping increases the absorption of visible light, and the urea doping enlarges the contact area, and simultaneously increases the open-circuit voltage and the short-circuit current density. The double nitrogen source doping forms a novel microstructure with more mesopores, the mesopores contain electrons and holes, the photoelectric conversion efficiency is improved by 7.58%, and the photoelectric conversion efficiency is improved by 14% compared with that of single nitrogen source doping titanium dioxide.

To summarize:

at present, the utilization of reclaimed water is one of the main measures for improving the utilization rate of water resources in many areas, but the application of the reclaimed water is mainly the reclaimed water which is convenient to collect, such as domestic sewage and the like. The collection and utilization technology of rainwater is still immature, and how to efficiently collect rainwater and more widely apply the treated rainwater becomes a problem to be solved urgently.

Because works have larger rainwater collection area and are drained by proper pipelines, the directional flow of rainwater can be ensured under various rainfall conditions, so that the higher rainwater collection efficiency is kept, and the rainwater utilization rate is ensured; meanwhile, in the process of collecting rainwater, the influence on the building body and the lighting inside the building can be avoided, and the normal life of residents can be guaranteed. Therefore, the product has extremely high practical application value.

For the collected rainwater, the treatment and storage processes are finished underground, so that the usable area on the ground is increased. The rainwater after the simultaneous processing is through concentrating the storage back, can be used for multiple use such as resident's carwash, afforestation irrigation, compares with traditional water use mode, the utility model discloses both greatly the cost is reduced, the use of manpower has been reduced simultaneously again. Therefore, the product can meet the basic requirements of residential living facilities.

According to calculation and analysis, if the device is put into use, the amount of rainwater collected in areas such as Beijing Tianjin and the like can reach thousands of tons every year, and areas with much rainfall, such as Shanghai, and the like, can collect more water resources.

In terms of cost, the prefabricated building can save a large part of resources firstly. Both human resources (number of workers) and materials, including outriggers, scaffold boards, forms, rebar, concrete, and the like, can be saved. In addition, the prefabricated assembly type construction site is more environment-friendly than a cast-in-place construction site, and waste materials are less. In the aspect of pipeline laying, only water pipes used by common buildings are needed, and extra cost cannot be increased. The added aspects of cost over existing buildings are the construction of water storage, utilization systems and purification devices.

The cost is calculated by taking a reservoir with the side length of 10 meters and the height of 3 meters as an example:

unit price of	Number of	Price/yuan
			Concrete/200 yuan per cubic meter	28.98 cubic meter	5796
Reinforcing steel bar/3000 yuan per ton	1136 kg	3408
			Digging/10 yuan per cubic meter	779.4 cubic meter	7794
Processing cost of reinforcing steel bar/500 yuan/ton	1136 kg	568
			Total up to	/	17566

According to calculation, the benefit of the collected rainfall is greater than the construction cost.

In conclusion, the product can bring higher economic benefit and social benefit in the aspects of resident residence and the like in many areas due to extremely high rain collecting efficiency and rainwater utilization rate, and has better application prospect.

The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings). In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

The invention has been described above by way of example, and it should be noted that any simple variants, modifications or other equivalent substitutions by a person skilled in the art without spending creative effort may fall within the scope of protection of the present invention without departing from the core of the present invention.

Claims

1. The utility model provides a hexagon building crowd system with collection rain afforestation function which characterized in that: comprises a building group, a rainwater harvesting greening reservoir and a central underground reservoir;

2. The hexagonal building group system with rain collecting and greening functions as claimed in claim 1, wherein: the rainwater collection greening reservoir comprises a water storage layer, a covering layer, a planting soil layer, a sand layer and a gravel layer from top to bottom.

3. The hexagonal building group system with rain collecting and greening functions as claimed in claim 2, wherein: perforated pipes are arranged in the gravel layer.

4. The hexagonal building group system with rain collecting and greening functions as claimed in claim 1, wherein: the comprehensive water consumption area adopts a water suction pump to pump water in the central underground water storage tank to the ground to be connected with a public toilet water consumption device, a fire-fighting emergency water source device and a self-service vehicle washing water consumption device.

5. The hexagonal building group system with rain collecting and greening functions as claimed in claim 1, wherein: the building adopts a fabricated building structure.

6. The hexagonal building group system with rain collecting and greening functions as claimed in claim 1, wherein: the upper surface of the building is covered with a photovoltaic device.

7. The hexagonal building group system with rainwater harvesting and greening functions as claimed in claim 6, wherein: the photovoltaic device adopts N-TiO₂A photovoltaic panel made of a dye-sensitized solar material.

8. The hexagonal building group system with rain collecting and greening functions as claimed in claim 1, wherein: the roof of the building is provided with a water collecting tank, the inner side wall of the building group is provided with a drainage water pipe, the drainage water pipe is connected with the water collecting tank, and rainwater in the water collecting tank is collected into a rainwater collection greening storage tank through the drainage water pipe.