Sponge city rainwater runoff control test device and use method thereof

Abstract

The application discloses a kind of sponge city rainwater runoff control test device and its using method, specifically related to precipitation test technical field, the test device includes sand table body, artificial simulated rainfall system, mode conversion module, drainage assembly and detection assembly, sand table body includes infrastructure model, traditional facility model and LID facility model, mode conversion module is arranged between traditional facility model and LID facility model, mode conversion module includes sliding cover and guide rail, guide rail is used to support sliding cover sliding.The application simulates rainfall and drainage in reality based on similarity theory, digital display screen displays the dynamic change curve of runoff before and after sponge conversion, the control ability of different types of sponge city facilities to rainwater runoff under different rainfall intensities can be studied, mode conversion module is set before and after the construction of sponge city, under the same rainfall condition, the control test of different LID facility models is realized.

Description

Technical Field

[0001] This invention relates to the field of precipitation testing technology, and more specifically, to a sponge city rainwater runoff control testing device and its usage method. Background Technology

[0002] Sponge city is a new generation of urban stormwater management concept. It refers to a city that can act like a sponge, exhibiting good resilience in adapting to environmental changes and coping with natural disasters caused by rainwater. It can also be called a water-resilient city. The internationally accepted term is low-impact development stormwater system construction. When it rains, it absorbs, stores, infiltrates, and purifies water. When needed, it releases and utilizes the stored water, which is conducive to restoring the urban water ecology, conserving water resources, enhancing the city's flood control capacity, expanding effective investment in public goods, improving the quality of new urbanization, and promoting the harmonious development of humans and nature.

[0003] The sponge city stormwater runoff control test device is an important tool for studying the effects of LID (Lightweight Industrialization) facilities and sponge city construction. Through dynamic tests of stormwater runoff control, the contribution rate of various types of LID facilities to stormwater runoff control can be effectively demonstrated, providing scientific guidance for optimizing the composition and selection of LID facilities.

[0004] Existing sponge city test devices are mostly simple tests on rainwater infiltration and water storage effects under a combination of several typical low impact development facilities. They lack water supply and drainage systems designed based on the principle of fluid mechanics similarity, and cannot achieve switching between LID facilities. The test data acquisition is relatively complex and not intuitive or concise enough. Summary of the Invention

[0005] The present invention provides a sponge city rainwater runoff control test device and its usage method. The problem to be solved is that other existing sponge city test devices are mostly simple tests on rainwater infiltration and water storage effects under a combination of several typical low impact development facilities. They lack water supply and drainage systems designed based on the principle of fluid mechanics similarity, and cannot realize the switching between LID facilities. The test data acquisition is relatively complicated and not intuitive and concise enough.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a sponge city stormwater runoff control experimental device, comprising a sand table body, an artificial simulated rainfall system, a mode conversion module, drainage components and a detection component, wherein the sand table body includes an infrastructure model, a traditional facility model and an LID facility model;

[0007] The artificial rainfall simulation system is used to spray water above the sand table to simulate rainfall;

[0008] The drainage system includes a first drainage network and a second drainage network. The first drainage network is used to collect infiltrated rainwater and overflow rainwater from each sand table model of the LID facility model, as well as excess runoff rainwater from each hard surface of the infrastructure model.

[0009] A mode conversion module is set between the traditional facility model and the LID facility model. The mode conversion module includes a sliding cover and a guide rail. The guide rail is used to support the sliding cover to slide. The sliding cover covers the corresponding sand table model in the corresponding traditional facility model or LID facility model to achieve the conversion of the test mode.

[0010] In a preferred embodiment, the infrastructure model includes a hardened plaza model, a building model, and a road model. The road model is equipped with rainwater inlets on its sides. The traditional facility model includes a traditional green space model and a hardened parking lot model. The LID facility model includes a sunken green space model, a rain garden model, and a permeable pavement model. The sunken green space model and the rain garden model are equipped with rainwater overflow pipes. The traditional green space model, the sunken green space model, the rain garden model, and the permeable pavement model are all supported by unit support frames, and the bottom of the unit support frames is equipped with drainage blind pipes.

[0011] Multiple sets of traditional green space models are set up. The sunken green space model is placed in correspondence with one set of traditional green space models, the rain garden model is placed in correspondence with another set of traditional green space models, and the permeable pavement model is placed in correspondence with the hardened parking lot model. The mode conversion module is also set up in three sets, which are respectively set on the sunken green space model and the traditional green space model, the rain garden model and the traditional green space model, and the permeable pavement model and the hardened parking lot model.

[0012] In a preferred embodiment, the test apparatus further includes a sand table base, with the sand table body set in the viewing frame. A support plate is provided on the top of the sand table base to support the sand table body and the viewing frame. An inspection area is provided inside the sand table base, and a water tank assembly is provided in the inspection area. The water tank assembly includes a first water tank and a second water tank. The first water tank is connected to a water tank inlet pipe and a water tank overflow pipe. The second water tank is provided with a water tank overflow pipe. A water supply pipe is provided between the first and second water tanks, located in the upper area. Both the first and second water tanks are provided with water tank drain pipes. The water tank drain pipes and water tank overflow pipes on the first and second water tanks eventually converge into the main water outlet pipe discharge device. The second water tank contains a reuse pump and a liquid level sensor. The water outlet pipe of the reuse pump is connected to the first water tank through the water supply pipe.

[0013] In a preferred embodiment, the artificial rainfall simulation system includes a water supply pipe with multiple sets of branch sprinkler pipes installed on it. The multiple sets of branch sprinkler pipes are evenly arranged above the sand table body. Stainless steel conical rain nozzles are installed on the branch sprinkler pipes. The water supply pipe is connected to a water supply pump, which is connected to a first water tank.

[0014] In a preferred embodiment, the first drainage network includes a first drainage main pipe, first drainage branch pipes, and road rainwater collection pipes. The first drainage main pipe is connected to a second water tank. Each road rainwater collection pipe is connected to a rainwater inlet set on the road model. The road rainwater collection pipes, rainwater overflow pipes, and drainage blind pipes in each group of sand table models of the LID facility model are connected to the first drainage main pipe through the first drainage branch pipes. The second drainage network includes second drainage branch pipes and a second drainage main pipe. The second drainage branch pipes are connected to drainage blind pipes in the traditional green space model. Each second drainage branch pipe is connected to the first water tank through the second drainage main pipe. The detection components include a main pipe flow meter and a humidity detector. The main pipe flow meter is installed on the first drainage main pipe to detect the flow rate of the first drainage network. The humidity detector is used to detect the relative humidity of the planting soil layer.

[0015] In a preferred embodiment, a baffle plate is provided around the top of the sliding cover, forming a collection groove on the top of the sliding cover. A drain pipe is provided at the bottom of the baffle plate, and the drain pipe is connected to the first water tank through a water pipe. A transverse sliding groove is provided on the guide rail. Sliding protrusions are provided on both sides of the sliding cover, and the sliding protrusions are slidably engaged in the transverse sliding grooves. A ball bearing is provided between the bottom of the sliding protrusion and the transverse sliding groove, and a sealing strip is provided on the top of the sliding protrusion.

[0016] In a preferred embodiment, a seepage guiding component is connected to the drainage blind pipe. The drainage blind pipe consists of an outer sponge layer and an inner built-in mesh pipe. Multiple holes are provided on the built-in mesh pipe. The seepage guiding component includes a transfer box. A positive pressure conveying channel is provided on the sliding cover plate. The positive pressure conveying channel is connected to an air inflation device through a pipe. A negative pressure suction pipe is fixedly connected to the transfer box. The negative pressure suction pipe is connected to the suction device.

[0017] In a preferred embodiment, a recessed area is provided on one side of the bottom of the transfer box. A large-diameter guide pipe and a small-diameter guide pipe are installed on the bottom of the transfer box. The small-diameter guide pipe is located in the recessed area. Both the large-diameter guide pipe and the small-diameter guide pipe are connected to the corresponding drainage pipe network. A large-flow rate analyzer is installed on the large-diameter guide pipe, and a small-flow rate analyzer is installed on the small-diameter guide pipe. A large-buoyancy float plug is slidably installed above the pipe opening of the large-diameter guide pipe, and a small-buoyancy float plug is slidably installed above the pipe opening of the small-diameter guide pipe. A guide ring is provided on the inner wall of the bottom of the transfer box. The large-buoyancy float plug and the small-buoyancy float plug are connected by a pull rope, which passes through the guide ring.

[0018] In a preferred embodiment, a filter structure is also installed in the transfer box. The filter structure is a flexible filter screen structure. The four sides of the filter structure are fixedly connected to the first drainage pipe network. The top of the large buoyancy float and the top of the small buoyancy float are both fixedly connected to a sliding rod. The sliding rod is slidably arranged in the transfer box, and the top of the sliding rod is fixedly connected to the filter structure.

[0019] A method for using a sponge city stormwater runoff control experimental device includes the following steps:

[0020] Step 1: Adjust the time relay of the PLC control system to set the rainfall duration, and then slide the sliding cover plate to the top of the sunken green space model, rain garden model and permeable pavement model in sequence.

[0021] Step 2: Turn on the rain switch to allow the water pump to draw water from the first water tank and evenly drop the water onto the surface of the sand table body through the conical nozzles at the end of the branch sprinkler pipes. When the rainfall time reaches the set time of the time relay, the artificial simulated rainfall system will automatically shut down, and the experimental group's test process will end.

[0022] Step 3: Slide the sliding cover plates onto the top of the adjacent traditional green space model and paved parking lot model in turn;

[0023] Step 4: Repeat Step 2 above to begin the control group test procedure;

[0024] Step 5: Turn on the return water switch, start the return pump, and pump water from the second water tank to the first water tank. When the liquid level in the second water tank drops to the low level, the low liquid level relay of the PLC control system will be activated, and the return water will be automatically shut off.

[0025] The beneficial effects of this invention are as follows:

[0026] This invention miniaturizes the underlying surface layout of an actual sponge city construction site to a proportional scale. Using the principle of fluid mechanics similarity, it sets up road / hard ground rainwater inlets, LID facility models, drainage blind pipes, and a drainage network system. This allows rainwater to gradually accumulate and generate runoff when simulated rainfall according to the rainstorm intensity formula. Part of the runoff enters the rainwater network system, while the rest is intercepted and absorbed by the LID facility model. This ensures that the demonstration of the entire device is more realistic and the experiment is more scientific.

[0027] This invention enables comparative tests of different LID facilities under the same rainfall conditions by setting up a mode conversion module before and after the construction of sponge cities. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0029] Figure 2 This is a schematic diagram of the internal structure of the viewing frame of the present invention.

[0030] Figure 3 This is a schematic diagram showing the distribution of each sand table model in this invention.

[0031] Figure 4This is a schematic diagram of the overall structure of the sand table base of the present invention.

[0032] Figure 5 This is a schematic diagram of the overall structure of the artificial rainfall simulation system of the present invention.

[0033] Figure 6 This is a schematic diagram of the overall structure of the first drainage pipe network of the present invention.

[0034] Figure 7 This is a schematic diagram of the overall structure of the second drainage pipe network of the present invention.

[0035] Figure 8 This is a simplified view of the mode conversion module of the present invention.

[0036] Figure 9 This is a schematic diagram of the improved mode conversion module of the present invention.

[0037] Figure 10 This is a cross-sectional view of the sliding cover plate after the mode conversion module of the present invention.

[0038] Figure 11 For the present invention Figure 10 Enlarged view of the structure of part A.

[0039] Figure 12 This is a schematic diagram of the overall structure of the seepage guiding component of the present invention.

[0040] Figure 13 This is a diagram showing the state of the present invention when the large-diameter guide pipe is closed and the small-diameter guide pipe is open when the seepage flow rate decreases.

[0041] Figure 14 This is a flowchart of the method of using the test apparatus of the present invention.

[0042] The attached diagrams are labeled as follows: 1. Model body; 11. Infrastructure model; 111. Hardened plaza model; 112. Building model; 113. Road model; 12. Traditional facility model; 121. Traditional green space model; 122. Hardened parking lot model; 13. LID facility model; 131. Sunken green space model; 132. Rain garden model; 133. Permeable paving model; 2. Model base; 21. Support plate; 22. Maintenance area; 23. Inspection door; 3. Viewing frame; 31. Unit support frame; 4. Artificial simulated rainfall system; 41. Water supply pipe; 42. Branch sprinkler pipe; 43. Water supply pump; 5. Mode conversion module; 51. Sliding cover plate; 511. Enclosure plate; 512. Drainage pipe; 513. Positive pressure conveying channel; 514. Sliding convex plate; 52. Guide rail; 521. Transverse chute; 6. Drainage assembly; 61. First drainage network; 611. First drainage main pipe; 612. First drainage branch pipe; 613. Road rainwater collection pipe; 614. Rainwater overflow pipe; 615. Drainage blind pipe; 6151. Built-in mesh pipe; 62. Second drainage network; 621. Second drainage main pipe; 622. Second drainage branch pipe; 7. Water tank assembly; 71. First water tank; 72. Second water tank; 721. Reuse pump; 722. Liquid level sensor; 73. Water tank inlet pipe; 74. Water tank overflow pipe; 75. Water replenishment pipe. 8. Pipe; 8. Detection Components; 81. Main Pipe Flow Meter; 82. Humidity Detector; 83. Large Flow Rate Separate Flow Meter; 84. Small Flow Rate Separate Flow Meter; 9. Seepage Guiding Components; 91. Transfer Box; 911. Recessed Area; 912. Guide Ring; 92. Negative Pressure Extraction Pipe; 93. Large Diameter Guide Pipe; 931. Large Buoyancy Plug; 94. Small Diameter Guide Pipe; 941. Small Buoyancy Plug; 95. Filter Structure; 96. Pull Rope; 97. Slide Rod. Detailed Implementation

[0043] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0044] Refer to the instruction manual appendix Figures 1 to 13 A sponge city rainwater runoff control experimental device includes a sand table body 1, a sand table base 2, a viewing frame 3, an artificial simulated rainfall system 4, a mode conversion module 5, a drainage component 6, a water tank component 7, a detection component 8, and a digital display system. The sand table body 1 is set in the viewing frame 3, and the viewing frame 3 and the sand table body 1 are set on the sand table base 2. The viewing frame 3 is made of four pieces of transparent tempered glass bonded together. The sand table body 1 includes an infrastructure model 11, a traditional facility model 12, and an LID facility model 13.

[0045] The infrastructure model 11 includes a hardened plaza model 111, a building model 112, and a road model 113. The hardened plaza model 111 is a hardened ground, which is modeled using acrylic sheets.

[0046] The main body of house model 112 is assembled from plastic sheets, and its bottom floor area is modeled using acrylic sheets.

[0047] The road model 113 is made of a non-deformable board. Support structures are provided on both sides of the bottom of the board to support it on the sand table base 2. The road model 113 is waterproofly bonded to the unit support frame 31 or other structures of other corresponding models in the surrounding area, and is designed with a slope. Rainwater inlets are set at certain intervals, and the rainwater inlets are connected to the road rainwater collection pipe 613.

[0048] The traditional facility model 12 includes a traditional green space model 121 and a hardened parking lot model 122. The traditional green space model 121 is supported by a unit support frame 31. The internal structure is arranged from bottom to top as follows: a gravel drainage layer (simulated by expanded clay), a planting soil layer, and a vegetation layer (simulated by simulated high-permeability turf). Drainage blind pipes 615 are installed in the gravel drainage layer. The height of the gravel drainage layer exceeds the height of the drainage blind pipes 615. The drainage blind pipes 615 in the traditional green space model 121 are connected to the second drainage branch pipe 622. The height of the planting soil layer is determined according to the overall elevation and slope of the sand table surface. The second drainage network 62 is connected to the traditional green space model 121 through the second drainage main pipe 621 and the second drainage branch pipe 622. The second drainage network 62 is connected to the water collection blind pipe of the drainage layer at the bottom of the green space and the first water tank at the end. It is used to collect the infiltrated rainwater of the green space and discharge it into the first water tank for reuse.

[0049] The hardened parking lot model 122 is a hardened ground, modeled using an acrylic sheet, 1cm thick, with a roughened surface.

[0050] LID facility model 13 includes a sunken green space model 131, a rain garden model 132, and a permeable paving model 133. The sunken green space model 131 consists of a gravel drainage layer (simulated by expanded clay), a planting soil layer, and a vegetation layer (simulated by simulated highly permeable turf, with model grass or model flowers placed on it) from bottom to top. The sunken green space model 131 is supported by a unit support frame 31, with a water storage layer reserved at the top. The gravel drainage layer contains a built-in drainage blind pipe 615, which is connected to the first drainage branch pipe 612. The sunken green space model 131 is equipped with a rainwater overflow pipe 614.

[0051] The rain garden model 132 consists of a gravel drainage layer (simulated by expanded clay), a transition layer (simulated by activated carbon particles), and a planting soil layer from bottom to top. The rain garden model 132 is supported by a unit support frame 31, and a sunken green space water storage layer is reserved in the upper part. The gravel drainage layer contains a built-in drainage blind pipe 615, which is connected to the first drainage branch pipe 612.

[0052] The permeable pavement model 133 consists of a gravel drainage layer (simulated by expanded clay), a dry-hardened cement mortar layer, and a permeable brick layer from bottom to top. The sunken green space model 131 is supported by a unit support frame 31. The gravel drainage layer contains a built-in drainage blind pipe 615, which is connected to the first drainage branch pipe 612.

[0053] It should be noted that in the above-mentioned sand table models, the paved plaza model 111, building model 112, road model 113, traditional green space model 121, and paved parking lot model 122 are sand table models of five types of traditional underlying surface facilities, while the sunken green space model 131, rain garden model 132, and permeable paving model 133 are sand table models of three types of typical LID (Land of Development) facilities. Details of each sand table model are provided in the appendix to the instruction manual. Figure 3 The layout is as shown. The main body of the sand table 1 is composed of various types of underlying surfaces. The surface elevation and slope design of the corresponding sand table model comply with the relevant provisions of the "Design Standard for Building Water Supply and Drainage" (GB 50015-2019). Among them, the traditional green space model 121, the sunken green space model 131, the rain garden model 132, and the permeable pavement model 133 are all supported by rectangular unit load-bearing frames 31 composed of transparent organic glass frames. The internal filling design of each is based on the "Technical Guidelines for Sponge City Construction - Construction of Low Impact Development Rainwater System (Trial)". Drainage blind pipes 615 are laid in the corresponding bottom gravel drainage layer to collect rainwater, and the height of the drainage blind pipes 615 matches the elevation system of the first drainage pipe network.

[0054] A mode conversion module 5 is provided between the traditional facility model 12 and the LID facility model 13. The mode conversion module 5 includes a sliding cover 51 and a guide rail 52. The guide rail 52 is used to support the sliding cover 51 to slide. The guide rail 52 is installed on the corresponding sand table model. The sliding cover 51 covers the corresponding sand table model in the traditional facility model 12 or the LID facility model 13 by sliding, so as to realize the conversion between the traditional mode and the LID mode. For details, please refer to the appendix of the instruction manual. Figure 2The configuration includes multiple sets of traditional green space models 121. Among them, the sunken green space model 131 is placed corresponding to one set of traditional green space models 121, the rain garden model 132 is placed corresponding to another set of traditional green space models 121, and the permeable pavement model 133 is placed corresponding to the hardened parking lot model 122. The mode conversion module 5 is also set to three sets, which are respectively placed on the sunken green space model 131 and the traditional green space model 121, the rain garden model 132 and the traditional green space model 121, and the permeable pavement model 133 and the hardened parking lot model 122. Correspondingly, by sliding the sliding cover plate 51 to cover the corresponding sand table model, the corresponding other sand table model can be exposed to conduct the corresponding mode test.

[0055] Refer to the instruction manual appendix Figure 4 The top of the sand table base 2 is provided with a support plate 21, which is used to support the sand table body 1. The sand table base 2 is a hollow enclosure structure with vertical steel supports inside. A ring of support structure is provided on the upper inner side of the sand table base 2. The support plate 21 is placed on the support structure, and the upper surface of the base cover plate is flush with the upper surface of the enclosure structure of the sand table base 2. A certain gap is left between the four edges of the support plate 21 and the inner wall of the enclosure structure of the sand table base 2 to form a slot for fixing the viewing frame 3. The side of the sand table base 2 is provided with an inspection door 23. The sand table base 2 is provided with a circuit control area (i.e., the actual control circuit of each device). The support plate 21 is hollowed out near the inspection door 23 to serve as an internal inspection area 22.

[0056] Refer to the instruction manual appendix Figures 5 to 7 The water tank assembly 7 includes a first water tank 71 and a second water tank 72. The first water tank 71 and the second water tank 72 are placed in the maintenance area 22 of the sand table base 2. The first water tank 71 is connected to a water tank inlet pipe 73 and a water tank overflow pipe 74. The second water tank 72 is equipped with a water tank overflow pipe 74. A water supply pipe 75 is installed between the first water tank 71 and the second water tank 72, located in the upper area. Both the first water tank 71 and the second water tank 72 are equipped with water tank drain pipes. The drain pipes and overflow pipes 74 on tank 71 and the second water tank 72 eventually converge into the main outlet pipe. The second water tank 72 contains a reuse pump 721 (submersible pump) and a level sensor 722. The level sensor 722 is located below the lowest level of the second water tank 72 to monitor the level of the second water tank 72 in real time. The outlet pipe of the reuse pump 721 is connected to the first water tank 71 through a water replenishment pipe 75 to replenish the water in the second water tank 72 to the first water tank 71.

[0057] Refer to the instruction manual appendix Figure 5The artificial rainfall simulation system 4 includes a water supply pipe 41, on which multiple sets of branch sprinkler pipes 42 are installed. These branch sprinkler pipes 42 are evenly arranged above the sand table body 1. Each branch sprinkler pipe 42 is equipped with a stainless steel conical rain nozzle. The water supply pipe 41 and the branch sprinkler pipes 42 form a high-resistance water distribution pipeline system. The water supply pipe 41 is connected to a water supply pump 43, which is connected to a first water tank 71. Water is supplied by the first water tank 71, enabling the system to handle three conditions: heavy rain, moderate rain, and torrential rain. The system includes a rainfall function, in which the water supply pipe 41 is a water distribution main pipe. The water supply pipe 41 is vertically raised to a certain height above the geometric center of the surface of the sand table body 1. A water distribution main pipe is installed at the top of the water supply pipe 41. The water distribution main pipe is connected to multiple equally spaced and symmetrically arranged branch sprinkler pipes 42 (i.e., water distribution branch pipes) in the horizontal direction. The ends of the branch sprinkler pipes 42 are connected to stainless steel conical rain sprinklers. The rainfall spray range can achieve full coverage of the surface of the sand table. The rated flow range of the conical rain sprinklers covers the design flow of three rainfall conditions.

[0058] Drainage assembly 6 includes a first drainage network 61 and a second drainage network 62, as shown in the attached instruction manual. Figure 6 The first drainage network 61 includes a first drainage main pipe 611, first drainage branch pipes 612, road rainwater collection pipes 613, rainwater overflow pipes 614, and drainage blind pipes 615. The first drainage main pipe 611 connects to the second water tank 72. Each road rainwater collection pipe 613 connects to a rainwater inlet installed on the road model 113. The rainwater overflow pipes 614 are installed in the sunken green space model 131 and the rain garden model 132. The drainage blind pipes 615 are installed in the gravel drainage layer of each LID facility model 13 (i.e.,...). In the gravel drainage layer of the sunken green space model 131, rain garden model 132 and permeable pavement model 133, the road rainwater collection pipe 613, rainwater overflow pipe 614 and drainage blind pipe 615 are connected to the first drainage main pipe 611 through the first drainage branch pipe 612. The first drainage network 61 is used to simultaneously collect infiltrated rainwater and overflow rainwater from each sand table model of LID facility model 13 and excess runoff rainwater from each hard surface of infrastructure model 11, and discharge it into the second water tank 72 for reuse.

[0059] Refer to the instruction manual appendix Figure 7 The second drainage network 62 includes a second drainage branch pipe 622 and a second drainage main pipe 621. The second drainage branch pipe 622 is connected to the drainage blind pipe 615 in the bottom gravel drainage layer of the traditional green space model 121. Each second drainage branch pipe 622 is connected to the first water tank 71 through the second drainage main pipe 621. The second drainage network 62 is used to collect the infiltrated rainwater of the traditional green space model 121 and discharge it into the first water tank for reuse.

[0060] The detection component 8 includes a main pipe flow meter 81 and a humidity detector 82. The main pipe flow meter 81 is installed on the first drainage main pipe 611 to detect the flow rate of the first drainage network 61 and thus determine the drainage effect of the system. The humidity detector 82 is used to detect the relative humidity of the planting soil layer and thus determine the seepage effect of the corresponding sand table model. Specifically, the humidity detector 82 is installed in the planting soil layer of the traditional green space model 121, the sunken green space model 131 and the rain garden model 132.

[0061] The digital display system includes a liquid level sensor 722, a detection component 8, a data conversion unit, a data cloud platform, and a display. The liquid level sensor 722 is used to collect liquid level data during the test; the main pipe flow meter 81 is used to collect relevant data such as drainage rate; the humidity detector 82 is used to collect the seepage effect and related data of the corresponding sand table model; the data conversion unit converts the above data into instantaneous detection data (including drainage flow data, humidity data of the corresponding sand table model, etc.); the data cloud platform is used to receive instantaneous flow data from the data conversion unit and transmit it to the display; the display shows the changes in runoff during the test in real time, and automatically calculates the total runoff control rate, peak runoff control rate, and peak runoff delay time after the test.

[0062] By setting up a liquid level sensor 722 to monitor water level changes in real time, and combining the flow rate in the first drainage main pipe 611 with the humidity detection of the corresponding sand table model, the above detection results are converted into runoff data. The data platform and display terminal automatically display the surface runoff change curves under the same rainfall conditions before and after the construction of the sponge city, and can automatically calculate the total runoff control rate, runoff peak reduction rate, and runoff peak delay time after the construction of the sponge city.

[0063] In the above embodiments, the corresponding sand table model can be covered and the mode can be switched by sliding the sliding cover plate 51. However, since the rainfall pattern of the artificial simulated rainfall system 4 is relatively uniform and can effectively cover the entire sand table body 1, although the sliding cover plate 51 can cover the corresponding sand table model, its surface will also receive rainwater, and the received rainwater will flow to other areas, affecting the accurate test judgment of other sand table models. Therefore, this embodiment improves the sliding cover plate 51. For details, please refer to the appendix of the specification. Figure 9 The top of the sliding cover 51 is surrounded by a baffle plate 511, which forms a collection trough on the top of the sliding cover 51. The bottom of the baffle plate 511 is provided with a drain pipe 512, which is connected to the first water tank 71 through a water pipe, thereby preventing the sliding cover 51 from guiding rainwater to other sand table models.

[0064] In the above embodiments, since the experimental device can perform simulation tests and conversion controls in real time, it can conduct multiple simulation tests continuously over a long period of time. Although the sunken green space model 131, rain garden model 132, and permeable pavement model 133 have good drainage performance, due to their numerous internal structures, their drainage is mainly based on infiltration. After the test is stopped, it is necessary to wait for the rainwater inside to fully infiltrate, but this process is relatively slow and requires a certain amount of time before subsequent tests can be conducted. Therefore, this embodiment also provides the following technical solution: connecting the infiltration guiding component 9 to the corresponding drainage blind pipe 615 and making corresponding improvements to the mode conversion module 5. Specifically, refer to the appendix of the instruction manual. Figures 9 to 13 The drainage blind pipe 615 consists of an outer sponge layer and an inner built-in mesh pipe 6151. Multiple holes are provided on the built-in mesh pipe 6151. The seepage guiding component 9 includes a transfer box 91. A positive pressure conveying channel 513 is provided on the sliding cover plate 51. The positive pressure conveying channel 513 is connected to an inflation device (air pump) via a pipe. This inflation device is used to convey gas into the positive pressure conveying channel 513. A negative pressure suction pipe 92 is fixedly connected to the transfer box 91. The negative pressure suction pipe 92 is connected to a suction device (air pump). This suction device creates negative pressure in the transfer box 91 through the negative pressure suction pipe 92. Taking the concave green space model 131 as an example, when it is necessary to change the test mode, the sliding cover plate 51 is pulled horizontally to the lower... Above the unit support frame 31 of the concave green space model 131, a sealed whole is formed with the unit support frame 31. At this time, each layer of material in the concave green space model 131 still retains a large amount of water. Then, air is injected into the unit support frame 31 through the positive pressure conveying channel 513, which increases the air pressure in the area above the concave green space model 131. This air pressure has a downward pushing effect on the water through the gaps between the filling components. At the same time, the air extraction of the negative pressure extraction pipe 92 causes the drainage blind pipe 615 to form a negative pressure at the bottom of the unit support frame 31, which helps to accelerate the discharge of residual water in conjunction with the high pressure above, so that the humidity of the corresponding filling material is restored to the standard state, ensuring that the initial state of the corresponding sand table model is the same in each test.

[0065] It should be noted that the seepage guiding component 9 mentioned above is mainly set for each sand table model of the LID facility model 13. If necessary, the drainage blind pipe 615 of the traditional green space model 121 can also be equipped with the seepage guiding component 9. In order to prevent air leakage between the sliding cover plate 51 and the unit support frame 31, please refer to the appendix of the instruction manual. Figure 11The guide rail 52 is provided with a transverse sliding groove 521, and the sliding cover plate 51 is provided with sliding protrusions 514 on both sides. The sliding protrusions 514 are slidably engaged in the transverse sliding groove 521, and ball bearings are provided between the bottom of the sliding protrusions 514 and the transverse sliding groove 521. A sealing strip is provided on the top of the sliding protrusions 514. When air is blown into the unit support frame 31, the sliding cover plate 51 tends to bulge upward, so that the sealing strip on the top of the sliding protrusions 514 can fit more tightly with the transverse sliding groove 521, improving the sealing effect. Similar sealing structures can also be provided at other positions of the sliding cover plate 51 to enhance the sealing.

[0066] Furthermore, in the above embodiment, during the initial discharge of seepage, the seepage volume is large, almost filling the entire pipe. Therefore, the flow meter structure installed on the pipe can effectively record the discharge flow rate, thereby effectively measuring and detecting the seepage discharge. However, in the later stages, the seepage rate slows down, and the seepage volume relatively decreases. Therefore, if the pipe is relatively large, the subsequent water volume is insufficient to fill the entire pipe, resulting in the flow meter structure being unable to accurately monitor the flow. If the pipe is small, it is difficult to meet the initial discharge requirements. To address this, this embodiment also provides the following technical solutions, specifically referring to the appendix to the specification. Figure 12 and Figure 13 A recessed area 911 is provided on one side of the bottom of the transfer box 91. A large-diameter guide pipe 93 and a small-diameter guide pipe 94 are installed at the bottom of the transfer box 91. The small-diameter guide pipe 94 is located at the recessed area 911. Both the large-diameter guide pipe 93 and the small-diameter guide pipe 94 are connected to the corresponding drainage pipe network. For example, in the LID facility model 13, the large-diameter guide pipe 93 and the small-diameter guide pipe 94 are connected to the first drainage branch pipe 612, and in the traditional green space model 121, the large-diameter guide pipe 93 and the small-diameter guide pipe 94 are connected to the second drainage branch pipe 612. A branch pipe 622 is connected. A large-flow classifier flow meter 83 is installed on the large-diameter guide pipe 93, and a small-flow classifier flow meter 84 is installed on the small-diameter guide pipe 94. A large-buoyancy float plug 931 is slidably installed above the pipe opening of the large-diameter guide pipe 93, and a small-buoyancy float plug 941 is slidably installed above the pipe opening of the small-diameter guide pipe 94. A guide ring 912 is provided on the bottom inner wall of the transfer box 91. The large-buoyancy float plug 931 and the small-buoyancy float plug 941 are connected by a pull rope 96, which passes through the guide ring 912.

[0067] It should be noted that in the same liquid, the buoyancy of the large buoyancy plug 931 is greater than that of the small buoyancy plug 941. When the seepage rate of the corresponding sand table model is relatively fast, the liquid level in the transfer box 91 is relatively high. Therefore, the large buoyancy plug 931 can float upwards, and then, under the action of the pulling rope 96, it pulls the small buoyancy plug 941 downwards, causing the small buoyancy plug 941 to block the opening of the small-diameter guide pipe 94. Refer to the instruction manual for details. Figure 12At this time, water is mainly discharged through the large-diameter guide pipe 93, which can adapt to a relatively fast discharge speed, and the large-flow fractional flow meter 83 performs accurate flow detection. When the seepage speed gradually slows down, the water level in the seepage guide component 9 drops relatively, the large buoyancy plug 931 drops, and seals the opening of the large-diameter guide pipe 93. At this time, there is still a certain water level in the recessed area 911, and the small buoyancy plug 941 floats up, so a small flow can be discharged through the small-diameter guide pipe 94. Since the diameter of the small-diameter guide pipe 94 is relatively small, it can be discharged in a full state at a relatively small seepage speed, so that the small-flow fractional flow meter 84 can effectively perform accurate detection. Moreover, when the water level drops, the large-diameter guide pipe 93 can be sealed before air enters it, and the drainage is switched to the small-diameter guide pipe 94. Therefore, the detection of the large-flow fractional flow meter 83 is always accurate and will not be affected by the venting of the large-diameter guide pipe 93.

[0068] Furthermore, since the aforementioned drainage blind pipe 615 primarily serves sand table models with planting soil layers, some soil and other materials will be discharged into the seepage guiding component 9 during actual discharge. If such materials are directly discharged into the first water tank 71 or the second water tank 72, it may affect the operation of the corresponding pumps. Therefore, a filter structure 95 is also installed in the transfer box 91. In the above solution, the filter structure 95 can directly use a fixed rigid filter plate structure, but the filtered material is prone to accumulate in local areas, affecting drainage. Therefore, this embodiment also provides the following solution, specifically... The filter structure 95 is a flexible filter screen structure. The filter structure 95 is fixedly connected to the first drainage pipe network 61 on all four sides. The top of the large buoyancy float 931 and the top of the small buoyancy float 941 are both fixedly connected to the slide rod 97. The slide rod 97 is slidably set in the transfer box 91, and the top of the slide rod 97 is fixedly connected to the filter structure 95. Therefore, in actual use, during the conversion between the large diameter guide pipe 93 and the small diameter guide pipe 94, the large buoyancy float 931 and the small buoyancy float 941 will drive the corresponding slide rod 97 to move up and down, thereby causing the filter structure 95 to deform and preventing the filter structure 95 from clogging.

[0069] Refer to the instruction manual appendix Figure 14 Referring to the above-described testing apparatus, this embodiment also provides a related testing method, namely, a method for using the above-described testing apparatus, specifically including the following steps:

[0070] Step 1: Adjust the time relay of the PLC control system to set the rainfall duration (i.e., the start duration of the water supply pump 43). Slide the sliding cover plate 51 to the top of the sunken green space model 131, the rain garden model 132 and the permeable paving model 133 in sequence, and make the sliding cover plate 51 fit tightly with the corresponding unit support frame 31.

[0071] Step 2: Turn on the rainfall switch to allow the water pump 43 to draw water from the first water tank 71. The water is then evenly distributed onto the surface of the sand table body 1 through the conical nozzles at the end of the branch sprinkler pipe 42. Users can directly observe the entire process of water accumulation, runoff, flooding, and drainage into the rainwater pipe network formed by the hardened plaza model 111, house model 112, and road model 113 on the sand table surface. They can also observe the real-time flow rate curve on the display to quantitatively understand the experimental results. When the rainfall time reaches the set duration of the time relay, the artificial rainfall system 4 automatically shuts down, i.e., the water pump 43 is turned off. Observe the curve on the display; when the flow rate drops to zero, it indicates the end of the experimental group's test process.

[0072] Step 3: Slide the sliding cover 51 onto the upper part of the adjacent traditional green space model 121 and hardened parking lot model 122 in turn, and make the sliding cover 51 fit tightly against them;

[0073] Step 4: Repeat Step 2 above and turn on the rain switch again to make the water supply pump 43 draw water from the first water tank 71 and evenly drop the water onto the surface of the sand table body 1 through the conical nozzle at the end of the branch sprinkler pipe 42. Start the control group test process. On the one hand, the user can directly observe the runoff rainwater formed by the hardened square model 111, house model 112 and road model 113 on the surface of the sand table and flow into each sand table model of LID facility model 13 according to the ground slope and form accumulation. Compared with the experimental group, the water accumulation points of the hardened square model 111 and road model 113 are significantly reduced and the runoff is significantly reduced. On the other hand, the user can observe the change curve of the pipe network flow in real time through the display and obtain the data difference between the control group and the experimental group.

[0074] Step 5: Turn on the return water switch and start the reuse pump 721 to pump the road runoff rainwater and the infiltrated rainwater from each sand table model of the LID facility model 13 in the second water tank 72 to the first water tank 71 for recycling. When the liquid level in the second water tank 72 drops to the low level, the low liquid level relay of the PLC control system is activated and the return water is automatically shut off.

[0075] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A device for testing sponge city rainwater runoff control, characterized in that: The sand table includes a sand table body, an artificial simulated rainfall system, a mode conversion module, a drainage assembly and a detection assembly, the sand table body includes infrastructure models, traditional facility models and LID facility models; The artificial simulated rainfall system is used for spraying water above the sand table body to simulate rainfall; The drainage assembly includes first and second drainage pipe networks, the first drainage pipe network is used for collecting infiltrated rainwater, overflow rainwater of the LID facility models and excessive runoff rainwater of hard surfaces of the infrastructure models; The mode conversion module is arranged between the traditional facility models and the LID facility models, the mode conversion module includes a sliding cover plate and a guide rail, the guide rail is used for supporting the sliding cover plate to slide, the sliding cover plate covers corresponding sand table models in the corresponding traditional facility models or LID facility models by sliding, and conversion of test modes is realized; The infrastructure models include hardened square models, house models and road models, the road models are provided with rainwater inlets on the sides, the traditional facility models include traditional green land models and hardened parking lot models, the LID facility models include sunken green land models, rainwater garden models and permeable pavement models, rainwater overflow pipes are arranged in the sunken green land models and the rainwater garden models, the traditional green land models, the sunken green land models, the rainwater garden models and the permeable pavement models are all carried by unit carrying frames, and drainage blind pipes are arranged at the bottom of the unit carrying frames; The drainage blind pipes are connected with seepage guide assemblies, the seepage guide assemblies include transfer boxes; One side of the bottom of the transfer box is provided with a sunken area, the bottom of the transfer box is provided with a large-diameter guide pipe and a small-diameter guide pipe, the small-diameter guide pipe is located at the sunken area, and the large-diameter guide pipe and the small-diameter guide pipe are connected with corresponding drainage pipe networks; a large-flow detection flowmeter is arranged on the large-diameter guide pipe, and a small-flow detection flowmeter is arranged on the small-diameter guide pipe; A large-float float is arranged above the pipe opening of the large-diameter guide pipe in a sliding mode, a small-float float is arranged above the pipe opening of the small-diameter guide pipe in a sliding mode, a guide penetrating ring is arranged on the inner wall of the bottom of the transfer box, the large-float float and the small-float float are connected through a pulling rope, and the pulling rope penetrates through the guide penetrating ring; A filter structure is further arranged in the transfer box, the filter structure is a flexible filter screen structure, the filter structure is fixedly connected with the first drainage pipe network around, the top of the large-float float and the top of the small-float float are fixedly connected with slide rods, the slide rods are arranged in the transfer box in a sliding mode, and the top ends of the slide rods are fixedly connected with the filter structure. 2.The device according to claim 1, wherein: The traditional green land models are arranged in multiple groups, the sunken green land models are placed corresponding to one group of the traditional green land models, the rainwater garden models are placed corresponding to another group of the traditional green land models, the permeable pavement models are placed corresponding to the hardened parking lot models, and the mode conversion modules are also arranged in three groups, the three groups of mode conversion modules are arranged on the sunken green land models and the traditional green land models, the rainwater garden models and the traditional green land models and the permeable pavement models and the hardened parking lot models respectively. 3.The device according to claim 2, wherein: The test device also includes a sand table base, the sand table body is arranged in the viewing frame, the top of the sand table base is provided with a support plate, the support plate is used for carrying the sand table body and the viewing frame, the inside of the sand table base is provided with an inspection area, the inspection area is provided with a water tank assembly, the water tank assembly includes a first water tank and a second water tank, the first water tank is connected with a water tank inlet pipe and a water tank overflow pipe, the second water tank is provided with a water tank overflow pipe, a water replenishing pipe is arranged between the first water tank and the second water tank, the water replenishing pipe is located in the upper area, the first water tank and the second water tank are provided with water tank drainage pipes, the water tank drainage pipes and the water tank overflow pipes of the first water tank and the second water tank finally converge into a water outlet main pipe discharge device, a reuse pump and a liquid level sensor are arranged in the second water tank, and the water outlet pipeline of the reuse pump is connected with the first water tank through the water replenishing pipe. 4.The device according to claim 3, characterized in that: The artificial simulated rainfall system includes a water supply pipe, a plurality of branch spray pipes are installed on the water supply pipe, and the plurality of branch spray pipes are uniformly arranged above the sand table body, a stainless steel conical rainfall spray head is arranged on the branch spray pipe, and the water supply pipe is connected with a water supply pump. 5.The device according to claim 4, characterized in that: The first drainage pipe network includes a first drainage main pipe, a first drainage branch pipe and a road rainwater collection pipe, the first drainage main pipe is connected with the second water tank, each road rainwater collection pipe is connected with a rainwater inlet arranged on the road model, and the road rainwater collection pipe, the rainwater overflow pipe and the drainage blind pipe in each sand table model of the LID facility model are connected with the first drainage main pipe through the first drainage branch pipe. 6.The device according to claim 5, characterized in that: The top of the sliding cover plate is provided with a surrounding baffle, the surrounding baffle forms a collection groove on the top of the sliding cover plate, the bottom of the surrounding baffle is provided with a drainage pipe, the drainage pipe is connected with the first water tank through a water pipe, a transverse sliding groove is arranged on the guide rail, sliding convex plates are arranged on the two sides of the sliding cover plate, the sliding convex plates are slidingly engaged in the transverse sliding groove, and rolling balls are arranged between the bottom of the sliding convex plate and the transverse sliding groove, and a sealing rubber strip is arranged on the top of the sliding convex plate. 7.The device according to claim 6, wherein: The drainage blind pipe is composed of an external sponge layer and an internal built-in mesh pipe, a plurality of holes are arranged on the built-in mesh pipe, a positive pressure conveying channel is arranged on the sliding cover plate, the positive pressure conveying channel is connected with an air charging device through a pipeline, and a negative pressure air suction pipe is fixedly connected to the transfer box.

8. The method of using the sponge city stormwater runoff control test device of claim 7, wherein, The method comprises the following steps: Step one, adjust the time relay of the PLC control system to set the rainfall time, and sequentially slide the sliding cover plate to the upper part of the sunken green space model, the rainwater garden model and the permeable pavement model; Step two, open the rainfall switch, make the water supply pump from the first water tank, and through the conical nozzle at the end of the branch sprinkler pipe, the water evenly falls on the surface of the sand table body. When the rainfall time reaches the time relay setting time, the artificial simulation rainfall system is automatically closed, and the experimental group test process is completed. Step three, slide the sliding cover plate to the upper part of the traditional green land model and the hardened parking lot model in turn; Step four, repeat step two above, start the control group test process; Step five, open the backwater switch, start the reuse pump, and pump the water in the second water tank to the first water tank. When the liquid level in the second water tank drops to the low water level, the low liquid level relay of the PLC control system starts, and the backwater is automatically closed.

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