Roof topography greening structure and its greening construction method

Abstract

The application provides a roof topography greening structure and a greening construction method thereof, relates to the technical field of roof topography greening, and comprises an extruded plate layer arranged in a stepped shape with the middle part being high and the four sides being low. The basic height of the undulating topography greening is cooperatively formed by the stacked extruded plate layer and a light nutrient soil water-retention and dust-reduction formula. The greening forming structure and the light nutrient soil formula used in the supporting green land planting together realize the functions of excellent water-retention, fertilizer-retention, dust reduction and adsorption of runoff pollutants, and the total load of the structure can be greatly reduced in cooperation with the roof topography greening forming structure.

Description

Technical Field

[0001] This invention relates to the field of terrain shaping technology, and more particularly to rooftop greening structures. Background Technology

[0002] Rooftop topography refers to creating micro-topography on rooftops to enrich the roof's landscape effect by shaping undulating terrain. This method includes steps such as roof pretreatment, plant placement, initial topography creation, shading netting for reinforcement, and topography reconstruction. Natural flowing terrain is sculpted using geotechnical greening structures and cultivation substrates, and the greening reconstruction of the terrain is then completed.

[0003] Current rooftop landscaping techniques mainly involve simple greening methods, using a common concrete raised floor, waterproof layer, and planting layer to complete rooftop greening. There is little research on techniques for creating undulating rooftop terrain. The common practice is to create slopes by piling up sand, which requires a large amount of sand, a long construction time, and puts significant pressure on the floor slab. Slopes made of pure sand gradually lose height as rainwater seeps in, resulting in insufficient terrain stability. Furthermore, the total load of soil used in these rooftop landscaping methods is very high, failing to meet the specifications for total roof load in construction projects. While lightweight substrate soil is commonly used for greening cultivation, this type of soil often has poor water retention after rooftop landscaping. After planting, the high transpiration rate due to sun exposure leads to low substrate water retention, resulting in high survival rates and high water consumption. Finally, because this type of soil uses lightweight matrix materials such as vermiculite, sand, and perlite commonly used in the market, it is less able to resist strong winds on the roof and is very prone to roof dust.

[0004] Therefore, there is an urgent need to develop a greening structure suitable for shaping undulating rooftop terrain. This structure should not only have stable structural characteristics, but also reduce the total load of the rooftop greening structure and its lightweight substrate while achieving good greening and planting. It should also improve the substrate's water retention rate, increase its adsorption capacity for runoff pollutants, improve the survival rate of transplanted plants, and reduce substrate dust problems. Summary of the Invention

[0005] To address the aforementioned technical issues, this application provides a roof undulating terrain shaping structure, comprising: a reinforced concrete overhead layer 1, an extruded polystyrene (XPS) board layer 2, reinforcing and fixing columns 3, and a steel grid 4; the XPS board layer 2 is laid on top of the reinforced concrete overhead layer 1, and the XPS board layer 2 is fixedly connected to the reinforcing and fixing columns 3. The XPS board layer 2 is arranged in a stepped, multi-layered manner with a higher center and lower edges, shaping an irregular, undulating mountainous terrain. XPS board corner fillers 201 are bonded to the stepped positions of the XPS board layer 2. A permeable geotextile layer 202 is laid on top of the XPS board layer 2 and the XPS board corner fillers 201. A steel grid 4 is installed on top of the permeable geotextile layer 202, and a backfill soil layer 401 is laid inside. The backfill soil layer 401 consists of two layers: a lower layer is a lightweight inorganic matrix, and an upper layer is a lightweight nutrient soil.

[0006] This application also provides a greening substrate for shaping rooftop undulating terrain. The substrate consists of two layers. The upper layer is a lightweight nutrient soil with the following raw materials in parts by weight: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water-retaining agent, prepared in a ratio of 100:30:10:10:10:10:15. The soil modifier is a mixture of bio-gum and surfactant in a 3:1 weight ratio. The bio-gum is xanthan gum or guar gum, and the surfactant is a cationic surfactant, preferably a highly soluble and highly moisturizing quaternary ammonium salt type. Octadecyl diester quaternary ammonium salt or hexadecyltrimethylammonium bromide; the water-retaining agent is starch: fly ash is mixed in a 3:2 ratio by weight; the specific preparation process is to first mix humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, and perlite in a certain proportion, add water at 20%-30% of the weight of the mixture, add the water-retaining agent, heat to 60-80℃ to dissolve, the starch is modified and gelatinized, and compacted to a compaction degree of 70-80%; the lower layer is a lightweight inorganic matrix, which includes the following raw materials in parts by weight: activated carbon, volcanic rock, and gravel, mixed in a 1:3:5 ratio.

[0007] Furthermore, between the reinforced concrete overhead layer 1 and the extruded polystyrene board layer 2, the following are also laid: a waterproof layer 101 is cement-bonded to the top of the reinforced concrete overhead layer 1, a plastic drainage board layer 102 is laid on top of the waterproof layer 101 with the protrusions facing upwards, a filter layer 103 is cement-bonded to the top of the plastic drainage board layer 102, an outer retaining wall 104 is built on top of the filter layer 103, and the extruded polystyrene board layer 2 is laid on the inner side of the outer retaining wall 104.

[0008] Furthermore, the inner slider 302 is axially slidably connected inside the reinforcing fixing post 3, and the outer pawl 301 is slidably connected in a ring array on the outer side of the inner slider 302. The inner threaded rod 303 is rotatably connected inside the reinforcing fixing post 3. The upper part of the reinforcing fixing post 3 is connected through an upper washer 304, and the upper outer side of the reinforcing fixing post 3 is threadedly connected to an upper threaded tube 305. The outer pawl 301 and the reinforcing fixing post 3 are slidably connected through the rod, the inner slider 302 is threadedly connected, and the upper end of the upper threaded tube 305 is rotatably connected to a positioning hook 306.

[0009] Furthermore, the positioning hook 306 and the steel grid 4 are hooked together, and the backfill soil layer 401 covers the outside of the positioning hook 306.

[0010] Furthermore, the reinforced fixing column 3 is slidably connected through the permeable geotextile layer 202 and the extruded polystyrene board layer 2, and the outer pawl 301 is slidably connected to the extruded polystyrene board layer 2.

[0011] This application also provides a greening construction method for a rooftop undulating greening structure, including the following steps:

[0012] 1. A reinforced concrete open space 1 is erected on the roof, with a lightweight partition wall structure at the bottom. The interior of the partition wall and the top cover plate of the open space are both reinforced with steel bars.

[0013] 2. The waterproof layer 101 at the top of the reinforced concrete overhead layer 1 is made of root-penetration resistant polyethylene polypropylene waterproof material. After it is laid, a layer of fine stone concrete is laid on top of it.

[0014] 3. The raised points of the plastic drainage board layer 102 on the waterproof layer 101 are laid upwards; the plastic drainage board layer is connected to the drainage pipe;

[0015] 4. The filter layer 103 on the plastic drainage board layer 102 is made of one layer of non-woven fabric;

[0016] 5. Measurement and layout: Conduct on-site measurement and layout according to the construction drawings to determine the position of the outer retaining wall 104 and construct it. Leave a water passage every 2-3m below.

[0017] 6. The inner side of the outer retaining wall 104 is covered with extruded polystyrene board layer 2. The layer is laid in layers according to the contour lines shown in the construction drawings. After the layer is laid, the corner filler 201 is used to fill the corners to make the overall terrain smooth and undulating. A drainage and settlement joint of 5-10cm is provided between each column of extruded polystyrene board in the longitudinal direction. The edge of the extruded polystyrene board layer is the concave area of ​​the terrain. The layer is laid at the end of this area.

[0018] 7. Lay two layers of permeable geotextile on the surface of the completed extruded polystyrene board layer 2;

[0019] 8. A lightweight inorganic matrix and a steel grid 4 of backfill soil layer 401 are laid on the surface of permeable geotextile layer 202. The thickness of the lightweight inorganic matrix under backfill soil layer 401 is consistent with the height of the steel grid.

[0020] 9. The reinforcing column 3 is inserted into the lower extruded polystyrene board layer 2, and the positioning hook 306 hooks the steel bar grid 4 so that the steel bar grid 4 cannot be displaced. The reinforcing column 3 is set at a certain interval.

[0021] 10. Lightweight nutrient soil is laid on the upper layer of backfill soil layer 401, and the lightweight nutrient soil backfill covers the steel grid 4; in the depression area between undulating terrain, there is no steel grid, only the backfill soil layer 401 is covered to form a drainage transition area, and the lower part of the backfill soil layer 401 is directly connected to the filter layer 103, that is, the backfill soil layer 401 is covered on the filter layer 103, so that it can be connected to the plastic drainage board layer 102 and drainage pipes under the filter layer 103.

[0022] 11. Adjust the terrain, complete the greening structure of the undulating terrain, and then transplant the vegetation.

[0023] Furthermore, the waterproof layer can be any commercially available waterproof material with root penetration resistance; it consists of 0.8mm thick root-penetration resistant polyethylene polypropylene waterproof membrane (core material thickness 0.6mm) + 1.3mm thick polymer cementitious adhesive + 0.8mm thick root-penetration resistant polyethylene polypropylene waterproof membrane (core material thickness 0.6mm) + 1.3mm thick polymer cementitious adhesive. The top of the waterproof layer is also protected by a 40mm thick C20 fine stone concrete layer, which is then combined into one layer. The filter layer is made of 200g / ㎡ non-woven fabric, which filters the silt and sand in the seepage water from the backfill soil layer.

[0024] Furthermore, the extruded polystyrene (XPS) board layers are arranged in a stepped shape, with a higher center and lower edges. The XPS board layers use 50kg / m³ XPS boards, with each layer being 200mm-300mm high. XPS board corner fillers are bonded to the stepped positions of the XPS board layers to make the overall terrain smooth. A permeable geotextile layer is laid on top of the XPS board layers and XPS board corner fillers. The XPS board layers are laid on the inner side of the outer retaining wall, and the basic height of the terrain is shaped by the stacking of XPS board layers.

[0025] Furthermore, the inside and top of the steel grid are covered with a backfill soil layer. The lower layer of the backfill soil layer is a lightweight inorganic matrix with a thickness consistent with the height of the steel grid. The upper layer of the backfill soil layer is a 200mm-350mm thick layer of lightweight nutrient soil. The upper layer of the backfill soil layer is lightweight nutrient soil, and the lower layer can filter the runoff from the upper layer.

[0026] This invention provides a rooftop greening structure, which has the following beneficial effects:

[0027] 1. This application is the first to successfully create a simulated contour-line undulating terrain on a rooftop greening structure, greatly enriching the rooftop landscape effect. By creating undulating terrain, a more diverse rooftop garden landscape can be created, enhancing the overall aesthetics. The basic height of the terrain is sculpted by layering extruded polystyrene (XPS) boards with lightweight nutrient soil containing water retention, adsorption, and dust reduction. This eliminates the need for soil layer accumulation, reduces the difficulty of creating the terrain slope, accelerates the construction speed, and shortens the construction time. Furthermore, the XPS board layer is lighter than the soil layer, reducing the weight pressure on the reinforced concrete support layer.

[0028] 2. The reinforced concrete overhead layer is waterproofed by a waterproof layer. The permeable geotextile layer on top of the waterproof layer and the permeable geotextile layer on top of the extruded polystyrene board provide double-layer filtration for particles such as mud and sand in the water seeping into the backfill layer. This reduces the impact of mud and sand carried by the water flow on the plastic drainage board layer and the waterproof layer, extends the service life of the plastic drainage board layer and the waterproof layer, and reduces the waterproof pressure on the reinforced concrete overhead layer and the waterproof layer.

[0029] 3. The steel reinforcement grid assists in fixing the backfill layer, reducing the risk of backfill layer flowing down the slope. The steel reinforcement grid is positioned by reinforcing fixing posts. During the installation of the reinforcing fixing posts, the outer pawl retracts to the inside of the reinforcing fixing posts, reducing the resistance to installation. After the reinforcing fixing posts are in place, the outer pawl moves to the outside of the reinforcing fixing posts and slides into the extruded polystyrene board layer. The outer pawl enhances the firmness of the reinforcing fixing posts and further reduces the probability of the reinforcing fixing posts becoming loose.

[0030] 4. The terrain created in this application using extruded polystyrene board and specialized lightweight nutrient soil significantly reduces the weight of the terrain, lowers the permanent load on the structure, improves the durability and safety of the structure, and creates a terrain effect that satisfies the owner. As of one year after the completion of Example 1, no quality problems such as settlement or cracking have been found.

[0031] 5. This application incorporates settlement joints between the longitudinal rows of extruded polystyrene (XPS) boards. The concave areas created by the XPS boards are transitioned only by backfill soil, forming a drainage transition zone. Heavy rainfall runoff can directly flow into these concave areas for emergency drainage. This ingenious design creates a network of drainage structures with excellent overall drainage capabilities: the micro-topography effectively removes accumulated water, reduces rainwater erosion of the roof, and extends its service life. It breaks away from the traditional design concept of placing a drainage layer on top of the XPS board, allowing deep-rooted trees and shrubs to be planted on top of the XPS board without affecting the stability of the concrete support layer. The uneven terrain quickly draws rainwater into the concave areas for drainage, while the longitudinal settlement joints of the XPS boards drain accumulated water from under the lightweight nutrient soil.

[0032] 6. To allow the public to intuitively experience the undulating terrain and the greening system built on it, as well as the process of rainwater purification and infiltration, we have designed a professional rooftop greening runoff pollutant adsorption matrix material. This material can purify and adsorb rainwater from the rooftop. Combined with the drainage structure in the micro-topographic depression area, the drainage process can be intuitively felt.

[0033] 7. The structure of this invention effectively utilizes urban rooftop space, providing the public with a recreational space while integrating the improvement of urban rainwater and the quality of urban public recreational spaces. It allows the public to participate in environmental protection and creates a complex with development potential that combines landscape recreation, undulating terrain shaping, rainwater purification, carbon sequestration and emission reduction, and building temperature reduction. This multifunctional facility, integrating recreational and static aesthetics, is the first of its kind in this invention. It cleverly utilizes a system with dual functions of rooftop greening and purification, and its visual appearance allows the public to intuitively experience the environmentally friendly design concept, making it non-obvious.

[0034] 8. This invention is the first to conduct in-depth research on the rooftop greening shaping structure and the lightweight nutrient soil formula used for supporting green space planting. Under the combined action, they achieve excellent water retention, fertilizer retention, dust reduction, and adsorption of runoff pollutants. In addition, when combined with the rooftop greening shaping structure, the total structural load can be greatly reduced. Attached Figure Description

[0035] To more clearly illustrate the technical solution of the present invention, the accompanying drawings will be briefly described below.

[0036] The accompanying drawings described below are only related to some embodiments of the invention and are not intended to limit the invention.

[0037] In the attached diagram:

[0038] Figure 1 A schematic diagram of the overall structure of this application is shown;

[0039] Figure 2 A structural schematic diagram of the reinforced fixing column of this application is shown;

[0040] Figure 3 This paper shows a structural schematic diagram of the cross-sectional state of the reinforced fixing column and the threaded tube of this application;

[0041] Figure 4 A schematic diagram of the external pawl structure of this application is shown;

[0042] Figure 5 A structural schematic diagram of the reinforced concrete elevated floor of this application is shown;

[0043] Figure 6 A schematic diagram of the structure of the extruded polystyrene board layer of this application is shown;

[0044] Figure 7 A structural schematic diagram of the steel reinforcement grid of this application is shown;

[0045] Figure 8 A schematic diagram of the reinforced concrete overhead floor, extruded polystyrene board floor, reinforced fixed columns, and steel grid in the present application is shown.

[0046] Figure 9 A schematic diagram showing the water retention rate of the water-retaining agent sample in the lightweight nutrient soil of this application is shown.

[0047] Figure 10 The response surface plots of different influencing factors of this application on the total load of lightweight nutrient soil are shown;

[0048] Figure 11 The response surface diagram of different influencing factors on the bulk density of lightweight nutrient soil is shown.

[0049] Figure 12 The residual normal distribution of the total load and unit weight of the lightweight nutrient soil of this application is shown;

[0050] Figure 13 The application shows a design drawing of the elevation line for roof topography shaping.

[0051] Figure 14 The application shows the construction drawings for shaping the roof terrain;

[0052] Figure 15 The application shows on-site construction photos of the roof terrain.

[0053] Figure label:

[0054] 1. Reinforced concrete raised floor; 101. Waterproof layer; 102. Plastic drainage board layer; 103. Filter layer; 104. External retaining wall;

[0055] 2. Extruded polystyrene board layer; 201. Extruded polystyrene board corner filler; 202. Permeable geotextile layer;

[0056] 3. Reinforced fixing post; 301. External pawl; 302. Internal slider; 303. Middle threaded rod; 304. Upper washer; 305. Upper threaded tube; 306. Positioning hook;

[0057] 4. Reinforcing steel grid; 401. Backfill soil layer. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Specifically, the accompanying drawings of this application only represent the vertical undulation structure of a certain area to facilitate a clear view of the internal layering changes in the terrain structure, and cannot represent the structure of all rooftop greening areas. In fact, the vertical and horizontal undulation structures of any rooftop area are within the scope of protection of this application.

[0059] Example 1: Please refer to Figures 1 to 15 :

[0060] The roof undulating terrain shaping structure includes: a reinforced concrete overhead layer 1, an extruded polystyrene board layer 2, reinforced fixing columns 3, and a steel grid 4; the extruded polystyrene board layer 2 is laid on top of the reinforced concrete overhead layer 1, and the reinforced fixing columns 3 are fixedly connected through the extruded polystyrene board layer 2. The extruded polystyrene board layer 2 is arranged in a stepped multi-layer pattern with a high center and low edges to create an irregular undulating mountain terrain. Extruded polystyrene board corner fillers 201 are bonded to the stepped positions of the extruded polystyrene board layer 2. A permeable geotextile layer 202 is laid on top of the extruded polystyrene board layer 202, and a steel grid 4 is set on top of the permeable geotextile layer 202. A backfill soil layer 401 is laid inside, which consists of two layers: a lower layer is a lightweight inorganic matrix, and an upper layer is a lightweight nutrient soil. Between the reinforced concrete overhead layer 1 and the extruded polystyrene board layer 2, the following is also laid: a waterproof layer 101 is cement-bonded to the top of the reinforced concrete overhead layer 1, a plastic drainage board layer 102 is laid on top of the waterproof layer 101 with the protrusions facing upwards, a filter layer 103 is cement-bonded to the top of the plastic drainage board layer 102, an outer retaining wall 104 is built on top of the filter layer 103, and the extruded polystyrene board layer 2 is laid on the inner side of the outer retaining wall 104. The reinforced fixing column 3 is axially slidably connected to an inner slider 302. An outer pawl 301 is slidably connected to the outer side of the inner slider 302 in a ring array. A central threaded rod 303 is rotatably connected to the interior of the reinforced fixing column 3. An upper washer 304 is threadedly connected to the upper part of the reinforced fixing column 3, and an upper threaded tube 305 is threadedly connected to the outer side of the upper part of the reinforced fixing column 3. The outer pawl 301 and the reinforced fixing column 3 are slidably connected through the threaded rod 303 and the inner slider 302. A positioning hook 306 is rotatably connected to the upper end of the upper threaded tube 305. The positioning hook 306 is hooked and connected to the reinforcing grid 4, and the backfill soil layer 401 covers the outside of the positioning hook 306. The reinforced fixing column 3 is slidably connected through the permeable geotextile layer 202 and the extruded polystyrene board layer 2, and the outer pawl 301 is slidably connected to the extruded polystyrene board layer 2. The inside and top of the steel grid 4 are covered with backfill soil layer 401. The lower layer of backfill soil layer 401 is a lightweight inorganic matrix, and the overall thickness is the same as the height of the steel grid. The upper layer of backfill soil layer 401 is lightweight nutrient soil.

[0061] The working principle of this invention: By shaping undulating terrain, the roof can create a richer roof garden landscape, enhancing the overall aesthetics and creating a richer landscape effect. The micro-topography can effectively drain water, reduce rainwater erosion on the roof, extend its service life, and provide good drainage. Roof terrain shaping helps reduce rainwater runoff, increase green area, and improve the urban ecological environment. By stacking extruded polystyrene board layer 2 to shape the basic height of the terrain, the work of stacking soil layers is eliminated, reducing the difficulty of shaping the terrain slope, accelerating the construction speed of terrain shaping, and shortening the construction time. The extruded polystyrene board layer 2 is lighter than the soil layer, reducing the weight pressure and load-bearing pressure on the reinforced concrete overhead layer 1.

[0062] The reinforced concrete overhead layer 1 is waterproofed by the waterproof layer 101. The water accumulated in the backfill soil layer 401 flows downward through the permeable geotextile layer 202. The filter layer 103 and the permeable geotextile layer 202 filter the silt in the water seeping into the backfill soil layer 401, reducing the loss of sand and extending the service life of the backfill soil layer 401. They also reduce the scouring of the plastic drainage board layer 102 and the waterproof layer 101 by the water carrying silt, extending the service life of the plastic drainage board layer 102 and the waterproof layer 101, and reducing the waterproof pressure on the reinforced concrete overhead layer 1 and the waterproof layer 101. The waterproof layer 101 is less affected by the external temperature by the extruded polystyrene board layer 2 and the backfill soil layer 401, reducing the aging and deformation of the waterproof layer 101 and extending its service life.

[0063] The reinforcing grating 4 provides auxiliary fixation for the backfill layer 401, reducing the risk of backfill layer 401 flowing downhill along the slope. The reinforcing grating 4 is positioned by the reinforcing fixing posts 3. First, installation holes for the reinforcing fixing posts 3 are drilled in the extruded polystyrene board layer 2. During installation, the threaded rod 303 rotates and moves downward through the guide inner slider 302. The inner slider 302 and the outer pawl 301 move downward synchronously. The outer pawl 301 retracts to the inside of the reinforcing fixing post 3, reducing the resistance to the installation of the reinforcing fixing post 3. After the reinforcing fixing post 3 is in place, the threaded rod 303 rotates and moves upward through the guide inner slider 302. The inner slider 302 and the outer pawl 301 move upward synchronously. The outer pawl 301 moves to the inside of the reinforcing fixing post 3. The outer side of the reinforced fixing column 3 and the extruded polystyrene board layer 2 are slid in. The outer pawl 301 enhances the firmness of the reinforced fixing column 3 and further reduces the probability of the reinforced fixing column 3 loosening. The multiple outer pawls 301 of the reinforced fixing column 3 at axial intervals simultaneously enhance the fixing effect between the superimposed extruded polystyrene board layers 2. The upper threaded pipe 305 is threadedly connected to the upper end of the reinforced fixing column 3. The positioning hook 306 moves from top to bottom to hook and fix the steel grid 4. The upper threaded pipe 305 presses down the upper gasket 304 to press down the permeable geotextile layer 202 to adhere to the extruded polystyrene board layer 2. The upper gasket 304 presses down to clamp and fix the opening position of the permeable geotextile layer 202, preventing the opening position of the permeable geotextile layer 202 from expanding to the surrounding area. Example 2

[0064] The greening construction method for the rooftop undulating greening structure, as described in Example 1, includes the following steps:

[0065] 1. A reinforced concrete open space 1 is erected on the roof, with a lightweight partition wall structure at the bottom. The interior of the partition wall and the top cover plate of the open space are both reinforced with steel bars.

[0066] 2. The waterproof layer 101 at the top of the reinforced concrete overhead layer 1 is made of root-penetration resistant polyethylene polypropylene waterproof material. After it is laid, a layer of fine stone concrete is laid on top of it.

[0067] 3. The raised points of the plastic drainage board layer 102 on the waterproof layer 101 are laid upwards; the plastic drainage board layer is connected to the drainage pipe;

[0068] 4. The filter layer 103 on the plastic drainage board layer 102 is made of one layer of non-woven fabric;

[0069] 5. Measurement and layout: Conduct on-site measurement and layout according to the construction drawings to determine the position of the outer retaining wall 104 and construct it. Leave a water passage every 2-3m below.

[0070] 6. The inner side of the outer retaining wall 104 is covered with extruded polystyrene board layer 2. The layer is laid in layers according to the contour lines shown in the construction drawings. After the layer is laid, the corner filler 201 is used to fill the corners to make the overall terrain smooth and undulating. A drainage and settlement joint of 5-10cm is provided between each column of extruded polystyrene board in the longitudinal direction. The edge of the extruded polystyrene board layer is the concave area of ​​the terrain. The layer is laid at the end of this area.

[0071] 7. Lay two layers of permeable geotextile on the surface of the completed extruded polystyrene board layer 2;

[0072] 8. A lightweight inorganic matrix and a steel grid 4 of backfill soil layer 401 are laid on the surface of permeable geotextile layer 202. The thickness of the lightweight inorganic matrix under backfill soil layer 401 is consistent with the height of the steel grid.

[0073] 9. The reinforcing column 3 is inserted into the lower extruded polystyrene board layer 2, and the positioning hook 306 hooks the steel bar grid 4 so that the steel bar grid 4 cannot be displaced. The reinforcing column 3 is set at a certain interval.

[0074] 10. Lightweight nutrient soil is laid on the upper layer of backfill soil layer 401, and the lightweight nutrient soil backfill covers the steel grid 4; in the depression area between undulating terrain, there is no steel grid, only the backfill soil layer 401 is covered to form a drainage transition area, and the lower part of the backfill soil layer 401 is directly connected to the filter layer 103, that is, the backfill soil layer 401 is covered on the filter layer 103, so that it can be connected to the plastic drainage board layer 102 and drainage pipes under the filter layer 103.

[0075] 11. Adjust the terrain, complete the greening structure of the undulating terrain, and then transplant the vegetation. Example 3

[0076] The rooftop topography shaping structure and construction of this invention were carried out in 2024 in the first phase of the landscaping project of the Zhangjiawan Vehicle Depot Comprehensive Utilization Land Supply Project in Tongzhou District, Beijing, specifically in the section 1 of the Dry Creek Water Feature. The structure described in Embodiment 1 of this invention adopts the following... Figure 13 contour lines and Figure 14The construction simulated undulating terrain for roof shaping. Testing showed that the total mass of the terrain shaped using this invention was approximately 60 tons, with a permanent load of approximately 0.8 T / m. 2 Compared to using only plain soil with a bulk density of 18 kN / m², the total mass is approximately 173 tons, and the permanent load is approximately 2.3 T / m². 2 Alternatively, lightweight soil with a bulk density ≤10KN / ㎡ can be used, with a total mass of approximately 96 tons and a permanent load of approximately 1.3T / m. 2 The total weight was reduced by 65.3% and 37.5% respectively. This demonstrates that the terrain filled and shaped using extruded polystyrene board and special lightweight nutrient soil significantly reduces the weight of the terrain, lowers the permanent load on the structure, improves the durability and safety of the structure, and creates a terrain effect that satisfies the owner. Construction has been completed for a full year to date, and no quality issues such as settlement or cracking have been found.

[0077] Specifically, the construction method for the rooftop greening structure in Example 2 uses the following materials: The reinforced concrete elevated layer 1 is 1.6m high, 130mm thick, and has a 160mm thick foundation wall at the bottom. Both the wall and the slab are reinforced with 12mm diameter Grade III steel bars, spaced 200mm apart in double rows and two directions. The waterproof layer 101 at the top of the reinforced concrete elevated layer 1 uses a 0.6mm thick root-penetration resistant polyethylene polypropylene waterproof membrane core material + 1.3mm thick polymer cementitious adhesive + 0.8mm thick root-penetration resistant polyethylene polypropylene waterproof membrane core material + 0.6mm thick polymer cementitious adhesive. The protective layer is 40mm thick C20 fine aggregate concrete. The plastic drainage board layer 102 on top of the waterproof layer 101 uses 30mm thick... A plastic drainage board with a height of mm is laid, with the protruding points facing upwards; a filter layer 103 on the plastic drainage board layer 102 is laid with one layer of 200g / ㎡ non-woven fabric; the layout is carried out on-site according to the construction drawings to determine the position of the outer retaining wall 104. The outer retaining wall 104 is a 240mm thick gray sand brick wall with a height of 500mm, and a water passage is left every 2m at the bottom; an extruded polystyrene board layer 2 is laid on the inner side of the outer retaining wall 104, using extruded polystyrene board with a specification of 50kg / m³, and each layer is 300mm high. After the large-scale layout is completed, corner fillers 201 are used to fill the corners, making the overall terrain smooth. A 10cm drainage settlement joint is provided between the extruded polystyrene boards. A permeable geotextile layer 202 is laid, with two layers of permeable geotextile (150g / m²) fully laid on the surface of the completed extruded polystyrene board layer 2. A lightweight inorganic matrix of backfill soil layer 401 and a steel grid 4 are laid on the surface of the permeable geotextile layer 202. The thickness of the lightweight inorganic matrix of backfill soil layer 401 is the same as the height of the steel grid, and the mesh size of the steel grid 4 after unfolding is 300. The length of the reinforcing column 3 is 300 mm, the width is 330 mm, and the height is 330 mm. The length of the reinforcing column 3 is 1.3 m. The reinforcing column 3 is inserted into the lower extruded polystyrene board layer 2. The positioning hook 306 hooks the steel grid 4 so that the steel grid 4 cannot be displaced. The spacing of the reinforcing columns 3 is 0.6 m. The reinforcing columns 3 are arranged in a staggered pattern. The lightweight nutrient soil of the backfill layer 401 is used to backfill and cover the steel grid 4. The lightweight nutrient soil of the backfill layer 401 is used for backfilling. The terrain is trimmed. The finished surface of the lightweight nutrient soil of the backfill layer 401 is trimmed manually. Example 4

[0078] As described in any of Examples 1-3, a greening substrate for shaping undulating roof terrain is provided. The substrate consists of two layers, with the upper layer being a lightweight nutrient soil. The formula includes the following raw materials in parts by weight: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water-retaining agent, prepared in a ratio of 100:30:10:10:10:10:15. The soil modifier is a mixture of bio-glue and surfactant in a 3:1 weight ratio. The bio-glue is... Xanthan gum or xanthan gum, with a cationic surfactant; the water-retaining agent is starch; fly ash is mixed in a 3:2 weight ratio; the specific preparation process is to first mix humus, loam, 0.5-5mm particle size natural sand, organic fertilizer, and perlite in a uniform ratio, add water at 20%-30% of the mixture weight, add the water-retaining agent, and heat to 60℃ to dissolve, causing starch modification and gelatinization, and compact to a compaction degree of 70-80%; the organic fertilizer is fermented chicken manure granules. The lower layer is a lightweight inorganic matrix, consisting of the following raw materials in parts by weight: activated carbon, volcanic rock, and gravel, mixed in a 1:3:5 ratio.

[0079] Experiment 1: Formulation and Performance Testing of Lightweight Nutrient Soil

[0080] Experimental Example 1

[0081] The formula for lightweight nutrient soil includes the following raw materials in parts by weight: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water-retaining agent, in a ratio of 100:30:10:10:10:10:15. The soil modifier is a mixture of bio-gum and surfactant in a 3:1 weight ratio. The bio-gum is guar gum, and the surfactant is a cationic surfactant, octadecyl diester quaternary ammonium salt. The water-retaining agent is a mixture of starch and fly ash in a 3:2 weight ratio. The specific preparation process involves first mixing the humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, and perlite in the specified proportions. Water is then added at 20%-30% of the mixture's weight. After adding the water-retaining agent, the mixture is heated to 60℃ to dissolve. After the starch undergoes gelatinization, the surfactant is added and mixed thoroughly. The mixture is then transferred to a simulated rooftop as a test sample and compacted to a compaction degree of 70%. The organic fertilizer is fermented chicken manure granules.

[0082] Experimental Example 2

[0083] The formula for lightweight nutrient soil includes the following raw materials in parts by weight: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water-retaining agent, mixed in a ratio of 100:30:10:10:10:10:15. The soil modifier is a mixture of biological gum and surfactant in a 3:1 weight ratio. The biological gum is xanthan gum, and the surfactant is a cationic surfactant, octadecyl diester quaternary ammonium salt. The water-retaining agent is a mixture of starch and fly ash in a 3:2 weight ratio. The specific preparation process involves first mixing the humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, and perlite evenly in the specified ratio. Water is then added at 20%-30% of the mixture's weight. After adding the water-retaining agent, the mixture is heated to 60℃ to dissolve. After the starch undergoes gelatinization, the surfactant is added and mixed thoroughly. The mixture is then transferred to a simulated rooftop as a test sample and compacted to a compaction degree of 70%. The organic fertilizer is fermented chicken manure granules.

[0084] Experimental Example 3

[0085] The formula for lightweight nutrient soil includes the following raw materials in parts by weight: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water-retaining agent, mixed in a ratio of 100:30:10:10:10:10:15. The soil modifier is a mixture of bio-gum and surfactant in a 3:1 weight ratio. The bio-gum is guar gum, and the surfactant is the cationic surfactant hexadecyltrimethylammonium bromide. The water-retaining agent is a mixture of starch and fly ash in a 3:2 weight ratio. The specific preparation process involves first mixing the humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, and perlite evenly in the specified ratio. Water is then added at 20%-30% of the mixture's weight. After adding the water-retaining agent, the mixture is heated to 60℃ to dissolve. After the starch undergoes gelatinization, the surfactant is added and mixed thoroughly. The mixture is then transferred to a simulated rooftop as a test sample and compacted to a compaction degree of 70%. The organic fertilizer is fermented chicken manure granules.

[0086] Experiment Example 4

[0087] The formula for lightweight nutrient soil includes the following raw materials in parts by weight: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water-retaining agent, in a ratio of 100:30:10:10:10:10:15. The soil modifier is a mixture of biological gum and surfactant in a 3:1 weight ratio. The biological gum is xanthan gum, and the surfactant is the cationic surfactant hexadecyltrimethylammonium bromide. The water-retaining agent is a mixture of starch and fly ash in a 3:2 weight ratio. The specific preparation process involves first mixing the humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, and perlite in the specified proportions. Water is then added at 20%-30% of the mixture's weight. After adding the water-retaining agent, the mixture is heated to 60℃ to dissolve. After the starch undergoes gelatinization, the surfactant is added and mixed thoroughly. The mixture is then transferred to a simulated rooftop as a test sample and compacted to a compaction degree of 70%. The organic fertilizer is fermented chicken manure granules.

[0088] Compare with Example 1

[0089] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the water-retaining agent is heated to 80°C.

[0090] Compare with Example 2

[0091] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the water-retaining agent is heated to 120°C.

[0092] Compare with Example 3

[0093] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the soil modifier is replaced with a mixture of bio-glue and surfactant in a 1:1 weight ratio.

[0094] Compare with Example 4

[0095] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the water-retaining agent is replaced with starch: fly ash in a 1:1 weight ratio.

[0096] Compare with Example 5

[0097] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the surfactant in the soil modifier is omitted.

[0098] Compare with Example 6

[0099] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the fly ash used as a water-retaining agent is omitted.

[0100] Compare with Example 7

[0101] The formula for lightweight nutrient soil is the same as in Experiment 1, except that the soil modifier and water-retaining agent are omitted.

[0102] Table 1 Performance Tests of Lightweight Nutrient Soil

[0103]

[0104] This application investigates the effects of different water-retaining agent compositions in lightweight nutrient soil on the aeration and moisture content of soil in a 1m*1m, 350mm thick test plot. Specifically, the tests were conducted 15 days after thorough watering to measure the soil moisture content (%) and aeration (maximum volumetric oxygen content per square meter of substrate, in m³). 3 / m 2 The results are shown in Table 1. The nutrient soil mixtures in Experiments 1-4 and Control Example 1 all exhibited good water retention performance, indicating that the addition of soil modifiers and water-retaining agents to the nutrient soil significantly improves its water retention capacity and increases soil aeration. The soil modifier is a mixture of bio-gum and surfactant in a 3:1 weight ratio. The bio-gum is xanthan gum or guar gum, and the surfactant is a cationic surfactant, preferably a highly soluble, high-moisture-retaining quaternary ammonium salt type, such as octadecyl diester quaternary ammonium salt or hexadecyltrimethylammonium bromide. The water-retaining agent is a mixture of starch and fly ash in a 3:2 weight ratio, which achieves better water retention and permeability in the nutrient soil.

[0105] The bio-gel modifier enables the nutrient soil to form a gel-like substance. After undergoing the sol and gel processes, the nutrient soil gradually forms a cross-linked three-dimensional network structure, resulting in excellent intermolecular stability. We also added cationic surfactants, which can reduce the surface tension of the nutrient soil, thus achieving better dust suppression in rooftop greening soil. Combined with water-retaining agents, it exhibits a synergistic effect. In particular, when we experimented with quaternary ammonium salt cationic surfactants and other anionic surfactants, we discovered that quaternary ammonium salt cationic surfactants can undergo an adhesion reaction with fly ash. Fly ash has a large number of hydrophilic hydroxyl groups on its surface, exhibiting good dispersibility in aqueous solutions. Through the salt ions in the soil modifier, it can achieve salt modification, utilizing the cations ionized by the salt modification to adhere to the fly ash surface, thereby enabling the fly ash to have ion exchange capabilities. Simultaneously, it increases micropores and specific surface area, releasing fly ash activity and enhancing its adsorption performance. Starch is a heat-modified starch. When heated in water to 60-80°C, it gelatinizes and forms a hydrophilic polymer with better moisturizing properties. When the temperature exceeds 100°C, the gelatinization reaction becomes excessive, which is not conducive to its water-retaining effect.

[0106] The wind speed was set to 7 m / s, and the nutrient soil was continuously blown for 30 minutes. A dust collection box was placed 30 cm away from each sample plot to collect and measure the dustfall at each point under the simulated wind speed. The weight of the dust collection box sample was also determined. The results showed that the addition of surfactants significantly improved the overall dust suppression rate of the nutrient soil. Modified starch and fly ash were used as water-retaining agents. Effective dust control of rooftop green spaces is necessary, and increasing surfactants can significantly improve the dust suppression rate of the nutrient soil test samples.

[0107] This experiment used artificial rainfall simulation, employing a 2-hour rainfall intensity as the experimental rainfall intensity to simulate rainfall runoff erosion. The raindrop velocity was 9.11 m / s, and the initial pollutant concentration of the simulated rainwater was 150.0 mg / L COD. After the simulated rainfall ended, water samples were collected from the bottom of the nutrient soil layer, and the COD content of the organic pollutants in the water samples was measured to calculate the percentage reduction. The study found that the addition of soil modifiers and water-retaining agents significantly improved the adsorption of COD, a common organic pollutant in urban rainwater runoff, by the nutrient soil. In particular, fly ash significantly promoted the adsorption of pollutants by the soil. Therefore, the structure of this invention effectively utilizes urban rooftop space, providing the public with a recreational space while integrating the improvement of urban rainwater and the quality of urban public recreational spaces. It allows the public to participate in environmental protection and creates a complex with development potential that combines landscape recreation, undulating terrain shaping, rainwater purification, carbon sequestration and emission reduction, and building temperature reduction. This multifunctional facility, which integrates recreational and static aesthetics, is the first of its kind in this invention. It cleverly utilizes a system with dual functions of rooftop greening and purification, and its visual appearance allows the public to intuitively experience the environmentally friendly design concept, making it non-obvious.

[0108] Experiment 2: Formulation and Performance Testing of Water-Retaining Agent for Green Roofs

[0109] The water retention rate determination involves accurately weighing 1 g of dried absorbent sample at room temperature, placing it in a 1 L beaker, adding 1 L of test liquid, and allowing it to stand until the absorbent material becomes saturated with water and forms a gel. Then, filter the gel through a 100-mesh sieve to remove free water, and allow the gel to stand on the sieve for 15 minutes. Finally, weigh the mass of the absorbent gel. Sample water retention rate (g / g) = (mass of absorbent gel - mass of dried sample) / mass of dried sample.

[0110] Figure 9 The water retention rates of the water-retaining agent samples show that Sample 1 (60° modified starch: fly ash in a weight ratio of 3:2) exhibits the smallest change in water retention rate with increasing water retention time. In other words, Sample 1 demonstrates superior water retention performance as water retention time increases. On the 6th day of the water retention experiment, its water retention rate remained at 80%. This was followed by Sample 2 (60° modified starch: hydroxymethyl cellulose powder in a weight ratio of 3:2) at 71%, Sample 3 (60° modified starch) at 62%, and Sample 4 (fly ash powder) at 51%.

[0111] Experiment 3: Response Surface Methodology for Influencing the Performance of Lightweight Nutrient Soil for Roof Greening

[0112] Experimental Method: The experimental test sample was 1m*1m, 200-500mm thick. The three independent variables—weight parts of amendment and water-retaining agent, and thickness of the nutrient soil (mm)—were implemented according to the process parameters in Table 2. The total load (T / m) was also used as the control. 2 Density kN / m3 As the response value. The formula of the lightweight nutrient soil is prepared according to the following weight parts: humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, and perlite, in a ratio of 100:30:10:10:10. The weight parts of soil modifier, water-retaining agent, and lightweight nutrient soil thickness (mm) are all prepared according to the experimental design in Table 1. The soil modifier is a mixture of guar gum and octadecyl diester quaternary ammonium salt in a weight ratio of 3:1. The water-retaining agent is a mixture of starch and fly ash in a weight ratio of 3:2. The preparation process is described in Example 3.

[0113] Table 2. Effects of different influencing factors on the properties of lightweight nutrient soil

[0114]

[0115] The Design-Expert 12.0 statistical analysis software was used to perform regression fitting analysis on the data in Table 2 to obtain the response value—total load T / m. 2 , bulk density kg / m 3 Factors influencing TCA-N content—the final response results of soil conditioner (A), lightweight nutrient soil thickness (B), and water-retaining agent (C) Figure 10-11 As shown in the figure, the results show that the changes in the numerical range of the three variables have significant differences in their effects on the total load and unit weight (P-value).

[0116] The response variable (total load) changes relatively slowly with increasing A (ammonia modifier) ​​(5→15); however, the change is more significant with increasing thickness B of the lightweight nutrient soil (200mm→500mm) (especially in the 300m–400m range). The surface slope is steeper in the B direction, and the color transitions from blue to red more quickly, indicating that a unit change in nutrient soil thickness has a stronger impact on the total load response value. The contour lines are denser in the Y-axis direction (thickness B), and the small spacing around 350mm indicates that small changes in B (e.g., ±50mm) cause large jumps in the response value. In contrast, the contour lines are sparser in the X-axis direction (ammonia modifier dosage), indicating that changes in the ammonia modifier result in a slower response. The contour lines are elliptical, indicating an interaction between A (ammonia modifier dosage) and B (nutrient soil thickness). Similarly, it can be seen that the changes in A (amendant) and C (water retention dosage), as well as the unit changes in B (nutrient soil thickness) and (water retention dosage), have a significant impact on the total load of the response value. Furthermore, the contour lines of A (amendant) and C (water retention dosage) are elliptical, indicating that A (amendant) and C (water retention dosage) also have an interaction (B and C have no interaction).

[0117] The response variable (bulk weight) changes significantly with increasing C (water-retaining agent dosage) (10→20) and B (lightweight nutrient soil thickness) (200mm→500mm). The surface slope is steeper in the C (water-retaining agent dosage) direction, and the color transitions from blue to red more rapidly, indicating that the unit change in the amount of water-retaining agent added has a stronger impact on the response value of bulk weight. The contour lines are denser in the Y-axis direction for C (water-retaining agent dosage) and (B thickness), indicating that small changes in C and B lead to large jumps in the response value. In contrast, the contour lines in the X-axis direction (A amendment dosage) are sparser, indicating that the response to changes in the amendment dosage is gradual. The contour lines in all three response plots are elliptical, indicating that there are interactions between A (amendment dosage) and B (nutrient soil thickness), B (nutrient soil thickness) and C (water-retaining agent dosage), and A (amendment dosage) and C (water-retaining agent dosage).

[0118] The predicted optimal formulation is: A (amendment dosage): 11 parts by weight, B (nutrient soil thickness): 332 mm, C (water retention dosage): 14 parts by weight. Under these conditions, the predicted total load for TCA-N is 0.84 T / m. 2 95 kg / m³ 3 Residual normal distribution Figure 12 The data shows a random distribution, meaning that the points for total load and unit weight are close to a straight line, indicating that the residuals are randomly distributed, the data have no special pattern, and the model assumptions are valid.

[0119] Experiment 4: The Influence of Different Specifications of Reinforcing Steel Grating, Extruded Polystyrene Board, and Backfill Soil on Structural Mechanical Performance Parameters

[0120] Experimental Methods: This experiment mainly studies the influence of different specifications of reinforcing grating, extruded polystyrene board, and backfill soil layers on structural bearing capacity and other parameters. Specifically, a five-layer trapezoidal structure of extruded polystyrene board was constructed using the design structure and method of Example 1 of this invention. The upper base of the sample was 0.5m long, and the lower base was 1.5m long. Rainfall runoff erosion was simulated, with raindrop diameter of 5mm and raindrop flow velocity of 9.11m / s. The effects of different dimensions of reinforcing grating, extruded polystyrene board, and backfill soil layers on the mechanical performance parameters (tensile strength, elongation at break, and joint bearing capacity) of the structure bottom were simulated after 3 hours of continuous rainfall. The upper component ratio of the backfill soil layer was the same as in Example 1, while the lower layer ratio was replaced as follows. The particle size distribution of the lower lightweight inorganic matrix layer is shown in Table 3.

[0121] Table 3. Particle size distribution of the lower layer (light inorganic matrix layer)

[0122]

[0123] Experimental Example 5

[0124] The rooftop greening structure is the same as in Example 1, wherein the steel grid mesh size is 300mm long * 300mm wide * 330mm high, and the extruded polystyrene board is 300mm high per layer; the lower layer of backfill soil is composed of activated carbon, volcanic rock, and gravel mixed in a ratio of 1:3:5.

[0125] Experimental Example 6

[0126] The rooftop greening shaping structure is the same as in Example 1, except that the steel grid mesh size is 200mm long * 200mm wide * 220mm high.

[0127] Experimental Example 7

[0128] The rooftop greening shaping structure is the same as in Example 1, except that the steel grid mesh size is 500mm long * 500mm wide * 550mm high.

[0129] Experimental Example 8

[0130] The rooftop greening structure is the same as in Example 1, except that each layer of extruded polystyrene board is 200mm high.

[0131] Experimental Example 9

[0132] The rooftop greening structure is the same as in Example 1, except that each layer of extruded polystyrene board is 400mm high.

[0133] Experimental Example 10

[0134] The rooftop greening structure is the same as in Example 1, wherein the lower layer of backfill soil is composed of activated carbon, volcanic rock, and gravel mixed in a ratio of 1:2:3.

[0135] Experimental Example 11

[0136] The rooftop greening shaping structure is the same as in Example 1, except that the lower layer of the backfill soil layer consists only of gravel graded as shown in Table 3.

[0137] Experimental Example 12

[0138] The rooftop greening structure is the same as in Example 1, except that the upper layer of the backfill soil is replaced with a commonly used lightweight substrate: humus, light sandy loam, perlite, and vermiculite mixed in a ratio of 10:5:4:1.

[0139] Experimental Example 13

[0140] The rooftop greening shaping structure is the same as in Example 1, except that the reinforced fixed columns are replaced with commonly used steel anchor rods of the same specifications.

[0141] Table 4 Comparison of mechanical property parameters under different experimental examples

[0142]

[0143] Experimental results:

[0144] We used a steel grid with dimensions of 300 mm long * 300 mm wide * 330 mm high. Below the backfill soil layer, activated carbon, volcanic rock, and gravel were mixed in a 1:3:5 ratio. On top, a lightweight nutrient soil formula from Example 1 (compared to the conventional lightweight matrix of Experiment 12) was laid. Extruded polystyrene boards were added in 300 mm high layers, and multiple layers were secured with reinforcing columns. This resulted in superior toughness and mechanical properties. After simulating rainfall on the roof topography shaping structure of this application, by adjusting the grid size, we found that the mechanical performance was better when the width and length of the steel ribs were arranged within the range of 200-300 mm. The tensile strength was higher in Experiments 5 and 6, and the elongation at break was lower. This indicates that the geogrid, after simulating rainfall runoff erosion force experiments using the roof structure and lightweight nutrient soil formula of this invention, exhibits superior mechanical performance parameters. In Experiment 7, when the size of the steel ribs increased, the joint bearing capacity decreased significantly and the elongation at break increased, showing good performance. This indicates that the structure is less stable and prone to deformation when rainfall is heavy.

[0145] When the height of the extruded polystyrene (XPS) board is too low (200mm), its tensile strength, elongation at break, and joint bearing capacity are not as good as when it is 300mm. Increasing the height to 400mm does not significantly improve tensile strength or joint bearing capacity. Therefore, the appropriate height of the XPS board should be selected based on construction costs. In the backfill soil layer, activated carbon, volcanic rock, and gravel can improve the matrix's adsorption efficiency of runoff pollutants. However, the addition of activated carbon should not be excessive. The gradation of volcanic rock should primarily be selected within the range of 4-6mm, as it has good permeability and structural stability. Furthermore, adding a small amount of 3mm gradation volcanic rock can provide a larger specific surface area, which is beneficial for the growth and reproduction of microorganisms and for maintaining a good root environment for plants.

[0146] In summary, it is evident that the rooftop shaping structure described in this application, along with the appropriately combined extruded polystyrene board, lightweight nutrient soil, and lightweight inorganic matrix layer used to fill and shape the terrain, significantly reduces the weight of the terrain, lowers the permanent load on the structure, improves the structure's durability and safety, and creates a terrain effect that satisfies the owner. To date, the experimental sample has been completed for a full year, and no quality issues such as settlement or cracking have been found.

[0147] The following points should be noted in this article:

[0148] 1. The accompanying drawings of the embodiments disclosed herein only involve structures relevant to the embodiments disclosed herein; other structures may refer to general designs.

[0149] 2. Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0150] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A rooftop undulating terrain greening structure, characterized in that, include: The structure consists of a reinforced concrete overhead layer (1), an extruded polystyrene board layer (2), reinforcing columns (3), and a steel grid (4). An extruded polystyrene board layer (2) is laid on top of the reinforced concrete overhead layer (1). The extruded polystyrene board layer (2) is connected to the reinforcing columns (3) through it. The extruded polystyrene board layer (2) is arranged in a stepped, multi-layered pattern with a higher center and lower perimeter, mimicking an irregular, undulating mountainous terrain. Extruded polystyrene board corner fillers (201) are bonded to the stepped positions of the extruded polystyrene board layer (2). The extruded polystyrene board layer (2) and the extruded polystyrene board corner fillers... The top of the corner piece (201) is covered with a permeable geotextile layer (202), and a steel grid (4) is set on the top of the permeable geotextile layer (202). The backfill soil layer (401) is laid inside. The backfill soil layer (401) consists of two layers. The lower layer is a lightweight inorganic matrix, and the raw materials include activated carbon, volcanic rock, and gravel. The upper layer is a lightweight nutrient soil, and the raw materials include humus, loam, natural sand with a particle size of 0.5-5mm, organic fertilizer, perlite, soil modifier, and water retention agent. Between the reinforced concrete overhead layer (1) and the extruded polystyrene board layer (2), a waterproof layer (101) is cement-bonded to the top of the reinforced concrete overhead layer (1), a plastic drainage board layer (102) is laid on top of the waterproof layer (101) with the protrusions facing upwards, a filter layer (103) is cement-bonded to the top of the plastic drainage board layer (102), an outer retaining wall (104) is built on top of the filter layer (103), and the extruded polystyrene board layer (2) is laid on the inner side of the outer retaining wall (104). The inner axial sliding connection of the reinforcing fixing post (3) is an inner slider (302), and the outer side of the inner slider (302) is an outer pawl (301) in a ring array. The inner threaded rod (303) is rotatably connected to the inside of the reinforcing fixing post (3). The upper part of the reinforcing fixing post (3) is connected through an upper washer (304), and the upper outer side of the upper part of the reinforcing fixing post (3) is threadedly connected to an upper threaded tube (305). The outer pawl (301) and the reinforcing fixing post (3) are slidably connected through each other, the middle threaded rod (303) and the inner slider (302) are threadedly connected, and the upper end of the upper threaded tube (305) is rotatably connected to a positioning hook (306). The positioning hook (306) and the steel grid (4) are hooked together, and the backfill soil layer (401) covers the outside of the positioning hook (306); The reinforced fixing column (3) is slidably connected through the permeable geotextile layer (202) and the extruded polystyrene board layer (2), and the external pawl (301) is slidably connected to the extruded polystyrene board layer (2).

2. The greening construction method for the rooftop undulating terrain greening structure according to claim 1, characterized in that, Includes the following steps: 1) A reinforced concrete open space is erected on the roof (1), with a lightweight partition wall structure at the bottom. The interior of the partition wall and the top cover plate of the open space are both reinforced with steel bars. 2) The waterproof layer (101) at the top of the reinforced concrete overhead layer (1) is made of root-penetration resistant polyethylene polypropylene waterproof material. After it is laid, a layer of fine stone concrete is laid on it. 3) The raised points of the plastic drainage board layer (102) on the waterproof layer (101) are laid upwards; 4) The filter layer (103) on the plastic drainage board layer (102) is made of one layer of non-woven fabric; 5) Measurement and layout: Perform on-site measurement and layout according to the construction drawings, determine the position of the outer retaining wall (104) and build it, leaving a water passage at certain intervals below; 6) The inner side of the outer retaining wall (104) is covered with extruded polystyrene board (2). The layers are laid in accordance with the contour lines shown in the construction drawings. After the layers are laid, the corner fillers (201) are used to fill the corners so that the overall terrain is smooth and undulating. Drainage and settlement joints are provided between each column of extruded polystyrene board in the longitudinal direction. The edge of the extruded polystyrene board layer is the concave area of ​​the terrain. After the layers are laid, there is no extruded polystyrene board layer in this area. 7) Lay two layers of permeable geotextile on the surface of the completed extruded polystyrene board layer (2); 8) A lightweight inorganic matrix and a steel grid (4) of backfill soil layer (401) are laid on the surface of the permeable geotextile layer (202). The thickness of the lightweight inorganic matrix under the backfill soil layer (401) is consistent with the height of the steel grid. 9) The reinforcing column (3) is inserted into the lower extruded board layer (2), and the positioning hook (306) hooks the steel bar grid (4) so ​​that the steel bar grid (4) cannot be displaced. The reinforcing column (3) is set at a certain interval. 10) Lightweight nutrient soil is laid on the upper layer of the backfill soil layer (401), and the lightweight nutrient soil backfill is covered with steel grid (4); in the depression area between undulating terrain, there is no steel grid, only the unfilled soil layer (401) is covered to form a drainage transition area. 11) Repair the terrain, complete the shaping of the green structure of the undulating terrain, and then transplant the vegetation.

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