Modular gradient purification rain garden system, monitoring method and construction method

Abstract

This invention discloses a modular gradient purification rain garden system, its monitoring method, and its construction method. Existing rain garden systems generally suffer from non-standard structures and inconvenient assembly. This invention, from top to bottom, includes a permeable paving layer, a bioretention layer, a capillary drainage layer, and a water storage and reuse layer. Each functional layer uses standard modular units, which are connected by stainless steel tenon and mortise connectors. Waterproof rubber sealing rings and bentonite sealing strips are installed at the joints of the standard modular units. Each functional layer is equipped with an intelligent monitoring unit, which includes a turbidity sensor, a pH sensor, a water level sensor, and a temperature sensor. All sensors are connected to a wireless module, and the sensor data is uploaded to a cloud-based prediction platform for centralized processing via a network. This invention improves the flexibility and convenience of rain garden systems during construction, installation, and subsequent maintenance.

Description

Technical Field

[0001] This invention belongs to the field of urban stormwater management and ecological drainage technology, specifically relating to a modular gradient purification rain garden system, monitoring method, and construction method. Background Technology

[0002] As an important facility under the Low Impact Development (LID) concept, rain gardens have been widely used in urban construction in recent years due to their ecological functions such as rainwater storage, pollution load reduction, and groundwater replenishment. However, existing rain garden systems still have significant shortcomings in terms of functional integration, structural versatility, construction efficiency, and intelligent operation and maintenance.

[0003] Currently, most rain garden designs rely on on-site filling with natural soil or artificial media, making it difficult to standardize structural layers and lacking unified interface methods between modules. This results in long construction cycles, significant quality fluctuations, and high costs for subsequent expansion and maintenance, especially in complex terrains or old urban areas where efficient deployment is not feasible. Furthermore, traditional rain gardens largely depend on natural gravity and manual operation and maintenance, lacking online monitoring methods for key indicators such as rainwater quality, water level changes, and system blockage. Their operational status is opaque, and once blockages or functional degradation occur, extensive excavation and repair are often required, severely impacting system lifespan and operational stability.

[0004] In terms of structural materials, existing rain garden drainage layers generally use gravel layers or ordinary water collection modules, lacking the ability to dynamically adapt to hydraulic performance under different climatic conditions. Drainage capacity fluctuates significantly in high or low temperature environments, failing to achieve true "climate-responsive management." Furthermore, some products sacrifice water retention capacity in pursuit of rapid drainage, which is detrimental to plant growth and ecological landscape construction. Regarding intelligent features, the market currently lacks integrated products that can work in conjunction with IoT platforms and AI algorithms, particularly in areas such as siltation early warning and remote maintenance control, where technological gaps exist.

[0005] In summary, existing rain garden systems generally suffer from problems such as non-standard structures, inconvenient assembly, lack of monitoring, poor control capabilities, and high maintenance difficulty. There is an urgent need for a new type of rain garden system that is modular in structure, standardized in connection, has intelligent monitoring and predictive response functions, and can be quickly deployed and efficiently maintained to improve and replace it. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention provides a modular gradient purification rain garden system, monitoring method, and construction method. It features high structural integration, fast construction efficiency, intelligent monitoring and predictive response functions, and can be quickly deployed and efficiently maintained.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A modular gradient purification rain garden system, specifically:

[0009] The system comprises four functional layers from top to bottom: a permeable pavement layer, a bioretention layer, a capillary drainage layer, and a water storage and reuse layer.

[0010] Each functional layer structure adopts standard modular units, and the standard modular units are connected by stainless steel tenon and mortise connectors.

[0011] Waterproof rubber sealing rings and bentonite sealing strips are installed at the joints of standard modular units;

[0012] Each functional layer is equipped with an intelligent monitoring unit, which includes a turbidity sensor, a pH sensor, a water level sensor, and a temperature sensor. All sensors are connected to a wireless module, and the sensor data is uploaded to a cloud prediction platform for centralized processing via the network.

[0013] Furthermore, the permeable pavement layer includes volcanic rock aggregate and a permeable concrete base layer.

[0014] Furthermore, the bio-retention layer is filled with a composite filler of iron-modified coconut shell fiber and rice husk charcoal.

[0015] Furthermore, the capillary conduction layer includes a polyethylene mesh, the interior of which is filled with a temperature-responsive hydrogel.

[0016] Furthermore, the water storage and reuse layer includes a water storage tank, the top of which is equipped with an overflow pipe that connects to the municipal water supply network; a disinfection module is installed inside the water storage tank.

[0017] Furthermore, the turbidity sensor is installed in the permeable pavement layer, the pH sensor is installed in the bioretention layer, the water level sensor is installed in the water storage and reuse layer, and the temperature sensor is installed in the capillary drainage layer.

[0018] Furthermore, it also includes a high-pressure water cleaning module.

[0019] Furthermore, a guide layer support column is provided below the polyethylene mesh.

[0020] A construction method for a modular gradient purification rain garden system includes the following steps:

[0021] Step 1: Excavation of the foundation trench and laying of high-density polyethylene geomembrane;

[0022] Step 2: Precisely position the water storage and reuse layer module using a hoisting method;

[0023] Step 3: Fill the polyethylene mesh of the capillary conduction layer with temperature-responsive hydrogel;

[0024] Step 4: Assemble the permeable pavement layer and bioretention layer modules, and install turbidity sensors, pH sensors, and water level sensors to complete the network;

[0025] Step 5: After passing the wireless signal test and data upload verification, the package is packaged and accepted.

[0026] A monitoring method for a modular gradient purification rain garden system, specifically:

[0027] First, sensors distributed across various functional layers, including turbidity, pH, water level, and temperature sensors, collect data in real time on key parameters of the rain garden system. The collected data is locally aggregated via wireless modules deployed within the system and wirelessly uploaded to a cloud-based prediction platform. On the cloud server, a pre-trained long short-term memory network model dynamically processes the uploaded data and predicts pollution trends. Subsequently, the system judges the current or predicted results based on the set judgment logic. If any parameter meets the preset threshold conditions, the system will trigger a maintenance response mechanism, output an alarm notification, and execute corresponding control operations.

[0028] The beneficial effects of this invention are:

[0029] 1) This invention improves the flexibility and convenience of rain garden systems in construction, installation and later maintenance by adopting a modular standard structure and mortise and tenon splicing method; each functional layer is composed of prefabricated units of uniform size, and high-strength sealing connection can be completed without the need for complicated tools during the splicing process, which effectively overcomes the problems of low assembly efficiency, poor sealing and difficulty in expansion of traditional rain garden on-site landfill structures, and significantly improves the efficiency of project implementation and system maintainability;

[0030] 2) In terms of structural layer design, this invention introduces temperature-responsive drainage materials and composite bioretention fillers, which can dynamically adjust the drainage capacity under different climatic conditions, while taking into account both water storage and ecological purification functions; the drainage layer can automatically enhance drainage capacity in high-temperature environments and maintain stable water storage in low-temperature environments, showing strong adaptability; the bioretention layer has good pollutant adsorption and decomposition performance, making the overall system operation more stable and the ecological performance more outstanding, meeting the rainwater management needs of different types of urban environments;

[0031] 3) This invention integrates an intelligent sensing and monitoring platform with a cloud-based predictive control platform, enabling real-time perception and intelligent response to the system's operating status. Through continuous monitoring of key water quality, water level, and operating conditions, combined with a cloud-based predictive model, it can promptly initiate cleaning, discharge, or alarm operations when the system experiences operational anomalies or potential blockage risks. This constructs an intelligent rainwater control system with self-detection, self-judgment, and self-execution capabilities, significantly improving the automation level and safety stability of the system operation. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the system's cross-sectional structure;

[0033] Figure 2 Detailed diagram of modular unit connections;

[0034] Figure 3 A three-dimensional structural diagram of the capillary packing layer;

[0035] Figure 4 Here is a flowchart of the intelligent monitoring system;

[0036] Figure 5 This is a schematic diagram of the construction process;

[0037] The components are as follows: 1-permeable pavement layer; 101-volcanic rock aggregate; 102-permeable concrete base layer; 2-bioretention layer; 201-iron modified coconut shell fiber; 202-rice husk charcoal; 3-capillary drainage layer; 4-water storage and reuse layer; 401-water storage tank; 402-ultraviolet disinfection module; 501-turbidity sensor; 502-pH sensor; 503-water level sensor; 701-tenon; 702-groove; 8-waterproof rubber sealing ring; 9-bentonite sealing strip; 10-polyethylene mesh; 11-temperature-responsive hydrogel; 12-drainage layer support column. Detailed Implementation

[0038] The present invention will now be described in detail with reference to specific embodiments.

[0039] This invention provides a modular gradient purification rain garden system, monitoring method, and construction method, which is suitable for urban squares, parks, rooftop green spaces, residential communities, and other areas for rainwater storage, filtration, purification, and reuse.

[0040] like Figure 1 , 2 As shown in Figures 1 and 3, the modular gradient purification rain garden system of the present invention includes four functional layers from top to bottom: a permeable paving layer 1, a bioretention layer 2, a capillary drainage layer 3, and a water storage and reuse layer 4.

[0041] The permeable pavement layer 1 includes volcanic rock aggregate 101 and permeable concrete base layer 102. The volcanic rock has a particle size of 5mm to 10mm and accounts for 30% to 40%. The concrete has a compressive strength of ≥15 MPa, a porosity of ≥25%, and a thickness of 100 to 150 mm. The thickness of this layer is controlled at 100 to 150 mm, which serves as a preliminary filter for rainwater and a means of dispersing structural loads.

[0042] The bioretention layer 2 is filled with a composite filler consisting of iron-modified coconut shell fiber 201 and rice husk charcoal 202. The iron-modified material has a specific surface area ≥200 m² / g, and the rice husk charcoal has a particle size of 2-5 mm. The mass ratio is 3:1, and the thickness is 300-400 mm. After being mixed evenly, the filler is laid with a thickness of 300-400 mm. This filler configuration can effectively adsorb and degrade COD, ammonia nitrogen, phosphate, and heavy metal ions.

[0043] The capillary drainage layer 3 includes a 3D-printed polyethylene mesh 10, which is filled with a temperature-responsive hydrogel 11. The polyethylene mesh 10 has a pore size of 10 mm × 10 mm, and the hydrogel has a phase transition temperature of 5–15 ℃, a low-temperature shrinkage rate of ≤5%, a high-temperature expansion rate of ≥20%, and a volume fraction of 40%–60%. It is used to dynamically adjust the drainage capacity according to the ambient temperature, achieving the automated operation goal of high-temperature rapid drainage and low-temperature water retention. Support columns 12 are installed below the polyethylene mesh 10, with an adjustable height range of ±10 mm, for overall leveling and installation adjustment. The temperature-responsive hydrogel operates stably in environments ranging from -10 ℃ to 40 ℃, with drainage flow fluctuations controlled within ±15%, achieving automatic adjustment to adapt to year-round climate changes.

[0044] The water storage and reuse layer 4 includes a polypropylene water storage tank 401 with a volume of 500-1000 L. The top of the water storage tank 401 is equipped with an overflow pipe 403, which is connected to the municipal pipe network and has an overcapacity protection function. The water storage tank 401 is equipped with an ultraviolet disinfection module 402 with a wavelength of 254 nm and a sterilization rate of ≥99.9%, which realizes rainwater collection, treatment and reuse. The treated rainwater can be reused for irrigation of plants in the park through a drip irrigation pipeline system.

[0045] Each functional layer structure adopts 1 m × 1 m standard modular units with a dimensional error of ≤1 mm. The standard modular units are connected by stainless steel tenon and mortise connectors. The stainless steel tenon and mortise connectors include stainless steel tenons 701 and matching grooves 702, which are set on the side wall of the module to form a plug-in tenon and mortise structure. The stainless steel tenon 701 has an outwardly convex rectangular tenon structure, and the groove 702 has an equilateral deep groove structure. The plug-in length is not less than 30 mm, the plug-in gap is less than 2 mm, the connection strength is not less than 200 MPa, and the splicing gap is controlled within 2 mm. The modular assembly method supports rapid hoisting and disassembly, with a splicing error of ≤3 mm. The splicing process is equipped with image recognition and laser level to automatically detect the splicing accuracy and module leveling status, improving construction efficiency by not less than 200% and reducing maintenance costs by not less than 60%.

[0046] The standard modular unit splice joints are equipped with a 5 mm thick waterproof rubber sealing ring 8 and a bentonite sealing strip 9 with a width of not less than 100 mm to enhance the joint's seepage prevention and displacement energy absorption capacity.

[0047] Each functional layer is equipped with an intelligent monitoring unit, which includes a turbidity sensor 501, a pH sensor 502, a water level sensor 503, and a temperature sensor. All sensors are connected to a LoRa or NB-IoT wireless module 504, and the sensor data is uploaded to a cloud prediction platform for centralized processing via the LoRa or NB-IoT network. The cloud prediction platform is equipped with an AI prediction module based on an LSTM model, which predicts the risk of system blockage based on historical data and performs response control in conjunction with set thresholds. The turbidity sensor 501 is located in the permeable pavement layer 1, the pH sensor 502 is located in the bioretention layer 2, the water level sensor 503 is located in the water storage and reuse layer 4, and the temperature sensor is located in the capillary drainage layer 3.

[0048] It also includes a high-pressure water cleaning module. When the permeability rate of the permeable layer drops by more than 30% of the initial value, the cloud platform issues a maintenance command and automatically starts a high-pressure nozzle with a pressure of 0.5 MPa to 1.0 MPa to perform periodic backwashing maintenance.

[0049] like Figure 5 As shown, the present invention also provides a construction method for a modular gradient purification rain garden system, comprising the following steps:

[0050] Step 1: Excavation of the foundation trench and laying of high-density polyethylene geomembrane;

[0051] Step 2: Precisely position the 4 modules of the water storage and reuse layer using a hoisting method;

[0052] Step 3: Fill the polyethylene mesh 1 of the capillary conduction layer 3 with temperature-responsive hydrogel 11;

[0053] Step 4: Assemble the permeable pavement layer 1 and bioretention layer 2 modules, and install turbidity sensor 501, pH sensor 502, and water level sensor 503 to complete the network;

[0054] Step 5: After passing the wireless signal test and data upload verification, the data is packaged and accepted. Specifically:

[0055] After the module is assembled, a pre-run test procedure must be performed. This test procedure includes the following steps: First, electrical connections and initial calibration of each sensor are performed to ensure stable sensor output values; then, the wireless communication module is started and a network connectivity test is conducted to verify whether the data can be successfully uploaded to the cloud prediction platform; after the connectivity verification is completed, simulated abnormal monitoring data is input into the system to conduct an alarm trigger test; after the system receives an abnormal signal, it feeds back the corresponding response signal through the platform interface and records the relevant response delay, alarm level, and action command; only after all test items are passed can the module enter the formal operation state and undergo sealing acceptance.

[0056] like Figure 4 As shown, the present invention also provides a monitoring method for a modular gradient purification rain garden system, specifically:

[0057] First, sensors distributed across various functional layers, including a turbidity sensor 501, a pH sensor 502, a water level sensor 503, and a temperature sensor, collect data on key parameters of the rain garden system in real time. The collected data is locally aggregated via a wireless module 504 deployed within the system and wirelessly uploaded to a cloud-based prediction platform. On the cloud server, a pre-trained long short-term memory network model dynamically processes the uploaded data and predicts pollution trends. Subsequently, the system judges the current or predicted results based on the set judgment logic. If any parameter meets the preset threshold condition, the system will trigger a maintenance response mechanism, output an alarm notification, and execute corresponding control operations.

[0058] Example 1:

[0059] The system is configured with the following threshold conditions: turbidity greater than 50 NTU for more than 2 hours, pH less than 6.0 or greater than 8.5, water level in the storage layer exceeding 90% of the tank's design capacity, or the AI ​​model indicating a blockage probability greater than 85%. Once any of these conditions are met, the platform will automatically issue an alarm and activate the backwashing system to perform high-pressure cleaning of the permeable layer, with the flushing pressure controlled between 0.5 and 1.0 MPa. Simultaneously, the platform can automatically switch the system operation mode to drip irrigation when the water level exceeds the limit, and upload and record the entire response process to form a maintenance log.

[0060] In practical applications, for example, a system covering an area of ​​120 m² was deployed in a city park, using 480 standard modules forming a four-layer structure, with 8 sets of intelligent monitoring nodes installed. After the system was built, it underwent a 30-day trial run in the spring, with a cumulative rainfall of 78 mm. The AI ​​model analysis determined that the blockage risk was below 20%, and no response was triggered. After three months of continuous use, some areas experienced a decrease in permeability due to leaf accumulation. Monitoring data showed that the infiltration rate dropped to 61% of its original value, and the turbidity sensor reading remained above 50 NTU for more than 2 hours. The AI ​​model predicted a value of 92%, and the system platform automatically triggered a three-level response command: sending an early warning, initiating backwashing, and resuming monitoring. After 6 minutes of cleaning, the infiltration rate recovered to 89% of its initial value, and the system returned to normal operation.

[0061] Example 2:

[0062] Deploying this system in rooftop green areas, it operated stably in high temperatures. The hydrogel within the capillary drainage layer expanded significantly when the ambient temperature reached above 40°C, increasing drainage speed by 17% without forming stagnant water zones on the surface. During winter, with a minimum operating temperature of -7°C, the hydrogel remained in a contracted state, preventing water from freezing. The UV disinfection module automatically entered intermittent operation. The entire system operated continuously and stably without failure for 180 days, consistently maintaining purification efficiency within the set target range.

[0063] This invention, through standardized structural combination, modular assembly, and intelligent monitoring and response linkage technology, can effectively improve rainwater purification efficiency and reduce construction and maintenance costs, and has significant environmental value and broad application prospects.

[0064] In the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," "link," and "fix" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0065] The content of this invention is not limited to the embodiments listed. Any equivalent modifications made by those skilled in the art to the technical solutions of this invention by reading this specification are covered by the claims of this invention.

Claims

1. A modular gradient purification rain garden system, characterized in that: The system comprises four functional layers from top to bottom: a permeable paving layer (1), a bioretention layer (2), a capillary drainage layer (3), and a water storage and reuse layer (4). Each functional layer structure adopts standard modular units, and the standard modular units are connected by stainless steel tenon and mortise connectors. Waterproof rubber sealing rings (8) and bentonite sealing strips (9) are provided at the joints of standard modular units. Each functional layer is equipped with an intelligent monitoring unit, which includes a turbidity sensor (501), a pH sensor (502), a water level sensor (503), and a temperature sensor; all sensors are connected to a wireless module (504) to upload sensor data to a cloud prediction platform for centralized processing via the network; The capillary conduction layer (3) includes a polyethylene mesh (10), and the polyethylene mesh (10) is filled with a temperature-responsive hydrogel (11); the temperature-responsive hydrogel (11) is used to dynamically adjust the conduction capacity according to the ambient temperature to achieve high-temperature fast discharge and low-temperature water retention.

2. The modular gradient purification rain garden system according to claim 1, characterized in that: The permeable pavement layer (1) includes volcanic rock aggregate (101) and permeable concrete base layer (102).

3. The modular gradient purification rain garden system according to claim 2, characterized in that: The bio-retention layer (2) is filled with a composite filler of iron-modified coconut shell fiber (201) and rice husk charcoal (202).

4. A modular gradient purification rain garden system according to claim 3, characterized in that: The water storage and reuse layer (4) includes a water storage tank (401), the top of which is provided with an overflow pipe (403) connected to the municipal pipe network; a disinfection module (402) is provided inside the water storage tank (401).

5. A modular gradient purification rain garden system according to claim 4, characterized in that: The turbidity sensor (501) is installed in the permeable pavement layer (1), the pH sensor (502) is installed in the bioretention layer (2), the water level sensor (503) is installed in the water storage and reuse layer (4), and the temperature sensor is installed in the capillary drainage layer (3).

6. A modular gradient purification rain garden system according to claim 5, characterized in that: It also includes a high-pressure water cleaning module.

7. A modular gradient purification rain garden system according to claim 6, characterized in that: A guide layer support column (12) is provided below the polyethylene mesh (10).

8. A construction method for a modular gradient purification rain garden system as described in any one of claims 1-7, characterized in that: Includes the following steps: Step 1: Excavation of the foundation trench and laying of high-density polyethylene geomembrane; Step 2: The water storage and reuse layer (4) module is precisely positioned using a hoisting method; Step 3: Fill the polyethylene mesh (10) of the capillary layer (3) with temperature-responsive hydrogel (11). Step 4: Assemble the permeable pavement layer (1) and bioretention layer (2) modules, and install the turbidity sensor (501), pH sensor (502), and water level sensor (503) to complete the network; Step 5: After passing the wireless signal test and data upload verification, the package is packaged and accepted.

9. A monitoring method for a modular gradient purification rain garden system as described in any one of claims 1-7, characterized in that: First, sensors distributed in each functional layer, including a turbidity sensor (501), a pH sensor (502), a water level sensor (503), and a temperature sensor, collect key parameters of the rain garden system in real time. The collected data is locally aggregated through a wireless module (504) deployed in the system and wirelessly uploaded to a cloud prediction platform. In the cloud server, a pre-trained long short-term memory network model dynamically processes the uploaded data and predicts pollution trends. The system then judges the current or predicted result according to the set judgment logic. If any parameter meets the preset threshold condition, the system will trigger the maintenance response mechanism, output an alarm notification and execute the corresponding control operation.

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