Slope repairing method based on stacked stones

Abstract

The invention relates to the technical field of side slope restoration, and discloses a side slope restoration method based on stacked stones, which comprises the following steps: step 1, collecting side slope basic data, and drawing a side slope section structure chart and a side slope facade structure chart according to the side slope basic data; 2, calculating the stability of the slope, and dividing the slope into a protection area, a restoration area and a reconstruction area according to the stability of the slope; step 3, aiming at the restoration area and the reconstruction area, evaluating the stress environment of each area, and selecting an area with a load condition meeting a substrate load standard as a substrate surface; selecting an area with a load condition meeting a transition load standard as a folding surface; the base surface and the folding surface are connected in series, and a stone stacking route is constructed; stone blocks are installed according to the stone stacking route; 4, vegetation ecological restoration is conducted on the protected area. The slope can be comprehensively repaired, the slope structure is optimized, the landscape function of the slope is improved, and the application function of the slope is expanded.

Description

Technical Field

[0001] The invention relates to the technical field of slope repair, and in particular to a slope repair method based on stone stacking. Background Art

[0002] Slope is a geological body with air-accessible conditions on the surface of the earth's crust, which is composed of the top, surface, foot and rock and soil of a certain depth below. When the stability of the slope is destroyed, it is easy to cause a variety of geological disasters, such as landslides, collapses, soil erosion, ground subsidence, etc., which are highly dangerous. In order to prevent and mitigate these dangers, a series of engineering measures and management measures are usually required, such as slope repair measures, which are engineering measures to reinforce and restore natural or artificial slopes. Its main purpose is to prevent the occurrence of disasters such as slope sliding and collapse, protect people's lives and property, and also help improve the beauty of the environment and ecological balance.

[0003] The development of existing slope repair technology can be traced back to the 1950s, when people began to use traditional slope repair technologies, such as retaining walls, anti-slide piles and anchoring. As time went on, people gradually realized that there were some problems with traditional slope repair technology, such as difficulty in construction, high cost, and great impact on the environment. In order to solve these problems, people began to research and develop new slope repair technologies. At present, slope repair technology has made great progress, and many new slope repair technologies have emerged, such as slope vegetation repair technology, slope ecological repair technology, and slope flexible repair technology.

[0004] Among them, vegetation slope repair technology is a technology that uses plants to repair damaged slopes. It plants plants on the slopes and uses the roots and rhizomes of the plants to fix the slopes, thereby improving the stability and safety of the slopes. Ecological slope repair technology is a technology that uses ecosystems to repair damaged slopes. It plants plants, microorganisms and animals on the slopes, and uses the self-repairing ability of the ecosystem to repair damaged slopes, thereby improving the stability and safety of the slopes. Flexible slope repair technology is a technology that uses flexible materials to repair damaged slopes. It lays flexible materials such as geogrids and geotextiles on the slopes, and uses the deformation ability of flexible materials to absorb the deformation and stress of the slopes, thereby improving the stability and safety of the slopes. Most of these repair technologies directly repair and reinforce the surface of the slopes, which can enhance the ecological functions of the slopes, but it is generally difficult to expand the application functions of the repaired slopes.

[0005] For mountainous cities, such as Chongqing, there are a large number of slopes throughout the urban area, especially in the old urban area and between the old urban area and the new development area. Due to the large terrain undulations, slopes are almost everywhere, occupying a large amount of land space. Moreover, compared with the slopes on both sides of the conventional river, these slopes often have larger and more complex geotechnical structures. For this type of slope, although the existing repair scheme can solve its ecological problems to a certain extent, the degree of repair for the geotechnical structure area is very limited, and it is still difficult to expand the application function of the repaired slope. For this type of slope structure concentrated in the urban area, it greatly limits the utilization rate of land and easily leads to the fragmentation of urban landscape, affecting the function of urban ecosystem and the quality of life of residents. Summary of the invention

[0006] The present invention aims to provide a slope repair method based on stone stacking, which can comprehensively repair the slope, optimize the slope structure, enhance its landscape function and expand its application function.

[0007] The basic solution provided by the present invention is: a slope repair method based on stone stacking, comprising the following steps:

[0008] Step 1: Collect basic slope data, and draw a slope profile structure diagram and a slope elevation structure diagram based on the basic slope data;

[0009] Step 2, calculating the slope stability, and dividing the slope into protection area, repair area and reconstruction area according to the slope stability;

[0010] Step 3: For the repair area and the reconstruction area, evaluate the stress environment of each area, select the area whose load conditions meet the base load standard as the base surface; select the area whose load conditions meet the transition load standard as the folding surface; connect the base surface and the folding surface in series to construct a stone stacking route; and install stones according to the stone stacking route;

[0011] Step 4: Carry out vegetation ecological restoration in the protected areas.

[0012] Further, in step 1, the basic slope data includes geological data and topographic data; the geological data includes rock and soil type, rock and soil layer, rock and soil structure, rock and soil physical and chemical properties and groundwater level; the topographic data includes contour lines, slope and slope direction.

[0013] Furthermore, in step 2, the finite element method is used to calculate the slope stability, and the slope is divided into a protection area, a repair area, and a reconstruction area according to a preset step threshold.

[0014] Furthermore, when installing stones according to the stone stacking route, a steel frame is first laid along the stone stacking route, and then a concrete retaining wall is processed on the base surface and the folding surface as a primary retaining wall; and then a planting trough is constructed on the base surface, and the planting trough is used to plant plants.

[0015] Furthermore, a secondary retaining wall is constructed on the outer side surface of the primary retaining wall of the folded surface and the outer side surface of the planting trough; the secondary retaining wall is a plastic stone retaining wall.

[0016] Furthermore, the plastic stone retaining wall is arranged in a layer-by-layer construction manner; and adjacent layers of plastic stones are arranged in a staggered manner to form plastic stone steps.

[0017] Furthermore, when calculating the stone stacking route, a route analysis model is used to automatically generate the stone stacking route; a CNN-GNN joint network is provided in the route analysis model; the CNN-GNN joint network includes an input layer, a CNN layer, an attention layer, a first fully connected layer, a GNN layer, a second fully connected layer and an output layer which are arranged in sequence; the CNN-GNN joint network takes the base surface, the folding surface, the slope profile structure diagram and the slope elevation structure diagram as inputs, takes the serial base surface and the folding surface as targets, and takes the stone stacking route and the corresponding risk level as outputs.

[0018] Furthermore, when calculating the stone stacking route, it also includes: when there are multiple stone stacking routes with equal risk levels, an auxiliary analysis model is also used to screen the stone stacking routes; an LSTM network is provided in the auxiliary analysis model; the LSTM network is used to learn the surface runoff conditions of the slope, and predict the degree of influence of the surface runoff on each stone stacking route; and the stone stacking route with the lowest influence is selected.

[0019] Furthermore, after the stone stacking route is constructed, the stone stacking route is also optimized; the optimization includes: setting a reference stone; based on the reference stone, previewing the stone stacking route to obtain a preview rendering; based on the preview rendering, verifying the road slope; and screening out sections that do not meet the slope reference value, and modifying the primary retaining wall size and stone size of this section to balance the road slope.

[0020] Furthermore, step 4 also includes setting a drainage ditch above the slope; setting a drainage ditch in the slope and at the bottom of the slope; the drainage ditch is associated with the planting trough to form a U-shaped structure, the drainage ditch is located at the bottom of the U-shaped structure, and is used to collect and guide surface runoff; the planting trough is located on both sides of the U-shaped structure.

[0021] The working principle and advantages of the present invention are:

[0022] The present invention provides a slope repair method based on stone stacking, which proposes a new slope repair angle, which is more suitable for the gentle slope repair scene in the urban area. Specifically, this scheme divides the slope into different areas, and sets repair strategies based on different areas. For the repair area and the reconstruction area, the stone stacking planning area is selected, and the stone stacking route is generated to construct the first retaining wall, the planting trough and the second retaining wall (plastic stone), which can fully stabilize the slope, and use the plastic stone and the planting trough to achieve landscaping and function expansion on the slope surface. Among them, the two can not only play a landscape and protection effect, but the plastic stone can also form a ladder, so that the slope has certain road attributes; the planting trough can expand the plant species on the slope. For the remaining protected areas, the vegetation ecological restoration method is used for restoration. This scheme can comprehensively repair the slope, optimize the slope structure, enhance its landscape function and expand its application function, better integrate into the urban system environment, and improve the utilization rate of the slope land in the city. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a method flow of a slope repair method based on stone stacking according to Embodiment 1 of the present invention;

[0024] Figure 2 It is a schematic diagram of the cross-sectional structure of a slope after repair in Embodiment 1 of a slope repair method based on stone stacking of the present invention;

[0025] Figure 3 It is a schematic diagram of the vertical structure of the slope after repair in Embodiment 1 of a slope repair method based on stacked stones of the present invention;

[0026] Figure 4 It is a schematic diagram of the planting trough structure of Embodiment 1 of a slope repair method based on stacked stones of the present invention;

[0027] Figure 5 It is a schematic diagram of a stone-plastic structure of a first embodiment of a slope repair method based on stone stacking of the present invention;

[0028] Figure 6 This is a simulation diagram of the repair effect of Example 1 of a slope repair method based on stone stacking according to the present invention. DETAILED DESCRIPTION

[0029] The following is a further detailed description through specific implementation methods:

[0030] Embodiment 1

[0031] The embodiment is basically as shown in the attached Figure 1 As shown: A slope repair method based on stone stacking, comprising the following steps:

[0032] Step 1: Collect the basic data of the slope, and draw the slope profile structure diagram and the slope elevation structure diagram based on the basic data of the slope.

[0033] In this step, the basic slope data include geological data and topographic data; the geological data include rock and soil types (types, thickness, and distribution of rock and soil layers), rock and soil strata (distribution of rock and soil layers, and stratigraphic relationships), rock and soil structures, rock and soil physical and chemical properties (density, porosity, compressive strength, shear strength, cohesion, internal friction angle, etc.), groundwater level and other data; the topographic data include contour lines, slopes, slope directions and other data.

[0034] Step 2: Calculate the slope stability and divide the slope into protection area, repair area and reconstruction area according to the slope stability.

[0035] In this step, the finite element method is used to calculate the slope stability, and the protection area, repair area and reconstruction area are obtained by dividing according to the preset step threshold. In this embodiment, the slope is first divided into multiple small units, and then based on the data collected in step 1, the geotechnical physical and mechanical parameters of each unit are input, and the boundary conditions of the slope (such as groundwater level) are set, and then the stress and strain of each unit are solved based on the existing finite element analysis software, and the slope stability is calculated to obtain the slope stability coefficient of each unit. Then, the protection area, repair area and reconstruction area are obtained by dividing according to the preset step threshold. The preset step threshold here is set based on the actual design requirements, and is set to 1.1, 1.05 and 1 in this embodiment. The area with a slope stability coefficient higher than 1.1 is the protection area, the area with a slope stability coefficient lower than 1 is the reconstruction area, and the rest is the repair area.

[0036] Step 3: For the repair area and the reconstruction area, evaluate the stress environment of each area, select the area whose load conditions meet the base load standard as the base surface; select the area whose load conditions meet the transition load standard as the folding surface; connect the base surface and the folding surface in series to construct the stone stacking route; and install the stones according to the stone stacking route.

[0037] In this embodiment, the base load standard and the transition load standard are set according to actual construction needs.

[0038] When calculating the stone stacking route, a route analysis model is used to automatically generate the stone stacking route; a CNN-GNN joint network is arranged in the route analysis model; the CNN-GNN joint network includes an input layer, a CNN layer, an attention layer, a first fully connected layer, a GNN layer, a second fully connected layer and an output layer which are arranged in sequence; the CNN-GNN joint network takes a base surface, a folding surface, a slope profile structure diagram and a slope elevation structure diagram as inputs, takes a series connection of a base surface and a folding surface as a target, and takes a stone stacking route and a corresponding risk level as outputs.

[0039] Specifically, the route analysis model is pre-trained with a slope data set, and during the training process, network optimization is performed through back propagation. The slope data set includes basic slope data of different slopes, rasterized slope profile structure diagrams and slope elevation structure diagrams; and the optimal path selection and risk level of each node are pre-marked on the slope profile structure diagram and slope elevation structure diagram.

[0040] When calculating the stone stacking route, it also includes: when there are multiple stone stacking routes with equal risk levels, an auxiliary analysis model is used to screen the stone stacking routes; an LSTM network is provided in the auxiliary analysis model; the LSTM network is used to learn the surface runoff of the slope and predict the degree of influence of the surface runoff on each stone stacking route; and the stone stacking route with the lowest influence is selected.

[0041] Specifically, the auxiliary analysis model is pre-trained using a slope environment data set; the training loss function uses a cross entropy loss function. The slope environment data set contains basic slope data, historical hydrological data, and historical meteorological data of the slope; the historical hydrological data includes groundwater level and surface runoff path, and the historical meteorological data includes rainfall, evaporation, etc.

[0042] After the stone stacking route is constructed, the stone stacking route is also optimized; the optimization includes: setting benchmark stones; based on the benchmark stones, previewing the stone stacking route to obtain a preview rendering; based on the preview rendering, verifying the road slope; and screening out sections that do not meet the slope benchmark value, and modifying the primary retaining wall size and stone size of this section to balance the road slope.

[0043] Specifically, in this embodiment, the reference stone is set as a standard unit cube (such as 1m 3 ), in order to facilitate unified quantitative analysis. The slope reference value is set to 6°.

[0044] When installing stones according to the stone stacking route, first lay the steel frame along the stone stacking route, then process the concrete retaining wall on the base surface and the folding surface as the primary retaining wall; then construct the planting groove on the base surface, and the planting groove is used to plant plants; Figure 4 shown.

[0045] A secondary retaining wall is also constructed on the outer side of the primary retaining wall of the folded surface and the outer side of the planting groove; the secondary retaining wall is a plastic stone retaining wall; Figure 2 , Figure 3 The plastic stone retaining wall is arranged in a layer-by-layer construction manner; and adjacent layers of plastic stones are arranged in a staggered manner to form plastic stone steps.

[0046] Specifically, when installing plastic stone, firstly, anchor the angle steel to the outer wall of the primary retaining wall or planting trough by anchor bolts, and then weld the angle steel to form a three-dimensional skeleton; on the three-dimensional skeleton, weld the steel bars to form a mesh; and tie the wire mesh shaping layer on the mesh, and then apply the shaping material on the wire mesh shaping layer to form plastic stone. The shaping material is a mixture of 1:2 cement mortar, fiber material and cementitious material. By controlling the size of the three-dimensional skeleton and the thickness of the shaping material, the size of the plastic stone can be controlled, such as Figure 5 shown.

[0047] Step 4: Carry out vegetation ecological restoration in the protected areas.

[0048] This step also includes setting a water intercepting ditch above the slope; setting a drainage ditch in the middle and at the bottom of the slope; the drainage ditch is associated with the planting trough to form a U-shaped structure, the drainage ditch is located at the bottom of the U-shaped structure, and is used to collect and guide surface runoff; the planting trough is located on both sides of the U-shaped structure. This arrangement can simultaneously meet the needs of drainage and vegetation growth, reduce the scouring of the slope by water flow, and help enhance the stability of the slope.

[0049] like Figure 6 As shown in the figure, this is the effect of the slope landscape restored by this solution. It has a strong landscape function, can be used as a rest and entertainment place for residents, and can also serve as a certain trail; and it effectively optimizes the slope structure.

[0050] The present embodiment provides a slope repair method based on stone stacking, which can comprehensively repair the slope and optimize the slope structure, thereby improving its landscape function and expanding its application function.

[0051] Embodiment 2

[0052] A slope repair method based on stone stacking is provided, based on the first embodiment, with adjustment made to step 3.

[0053] In step 3, after the stone stacking route is constructed, the stone stacking route is further optimized for a second time.

[0054] The secondary optimization includes: collecting satellite image data of the area where the slope is located; the satellite image data refers to satellite image data. Based on the satellite image data, the environmental features around the slope are extracted; in this embodiment, the extracted environmental features specifically include: environmental features of the area adjacent to the bottom of the slope and the area adjacent to the top of the slope; including static features such as rivers, roads, buildings, and dynamic features such as pedestrian and vehicle traffic.

[0055] In this embodiment, the maximum flow of people on the stone stacking route of the slope is predicted based on the dynamic feature of the flow of people (the LSTM network model is used for prediction here), and the maximum load added on the base surface and the folding surface on the stone stacking route is estimated based on the maximum flow of people; and compared with the load conditions of the base surface and the folding surface calculated in step 3, if the load conditions can meet the maximum load, no adjustment is made; if the load conditions do not meet the maximum load, the base surface or folding surface that does not meet the load conditions is reinforced.

[0056] The slope repair method based on stone stacking provided in this embodiment can further verify and optimize the set stone stacking route to ensure that the route finally constructed can meet the safety requirements when the slope is used as a functional area such as a road / climbing area.

[0057] Embodiment 3

[0058] A slope repair method based on stone stacking, based on the first embodiment, before step 2, further performs a stone stacking feasibility analysis.

[0059] The feasibility analysis of stacking rocks includes: collecting satellite image data of the area where the slope is located; the satellite image data refers to satellite image data. Based on the satellite image data, the environmental features around the slope are extracted; in this embodiment, the extracted environmental features specifically include: environmental features of the area adjacent to the bottom of the slope and the area adjacent to the top of the slope, including static features such as rivers, roads (including driving roads and non-driving roads), buildings, and dynamic features such as pedestrian flow and vehicle flow.

[0060] Check whether there are risk features in the environmental features, including rivers and driving roads; if there are risk features, and the distance between the risk feature and the bottom or top of the slope is less than the preset safety value (such as 100m), the feasibility of stone stacking of the slope is output as 0. If there are no risk features, based on each environmental feature, with the bottom or top of the slope as the target point, calculate the walking accessibility of the slope under the influence of the environmental features, and use the walking accessibility as the feasibility of stone stacking of the slope.

[0061] The slopes whose feasibility of stone stacking reaches the preset threshold are selected for stone stacking-based slope repair. For the slopes whose feasibility of stone stacking does not reach the preset threshold, conventional methods can be used for repair.

[0062] The present embodiment provides a slope repair method based on stone stacking, which analyzes the surrounding environment of the slope to calculate the feasibility of stone stacking of the slope, that is, calculates whether the slope is suitable for the slope repair method based on stone stacking, thereby ensuring that the application of the method can be adapted to the specific slope environment.

[0063] Embodiment 4

[0064] A slope repair method based on stone stacking, based on the first embodiment, when the slope is a small slope, one stone stacking route is selected. When the slope is a medium slope or a large slope, multiple stone stacking routes can be selected.

[0065] Among them, small slopes refer to slopes with a height of no more than 10m and a length of no more than 50m. Medium slopes refer to slopes with a height between 10m and 30m and a length between 50m and 200m. Large slopes refer to slopes with a height of more than 30m and a length of more than 200m. For medium and large slopes with a wider impact range, setting up multiple stone stacking routes is more convenient for completely covering the slope area.

[0066] Furthermore, when the slope is a medium-sized slope or a large-sized slope, the line analysis model automatically generates the stone stacking route with the top and bottom of the slope as the starting and ending points, the serial base surface and the folding surface as the target, and the stone stacking route and the corresponding risk level as the output.

[0067] When selecting the starting and ending points from the top and bottom of the slope, the flow characteristics of people in the adjacent area at the top of the slope and the flow characteristics of people in the adjacent area at the bottom of the slope can be combined to select a point with a large flow of people (such as more than 200 people per hour) as the starting point and a point with a small flow of people (such as less than 100 people per hour) as the end point. In this way, the generated stacked stone route can better play its application function as a road and help disperse the flow of people.

[0068] And select and retain several stone stacking routes with risk levels higher than a threshold (this threshold is set according to actual construction needs).

[0069] If further selection of routes is required, the auxiliary analysis model is used to screen the stone stacking routes; the stone stacking routes with an influence lower than a threshold (this threshold is set according to actual construction needs) are selected.

[0070] Furthermore, for different stone stacking routes, different sizes of reference stones can be selected when installing stones, such as 1m 3 Benchmark stone, 1.2m 3 Benchmark stone, 0.8m 3 The reference stones are used to form stacked stone roads of different spans. This arrangement can enrich the landscape effect of the stacked stone area while providing walking routes of different spans to meet the needs of different groups of people.

[0071] The present embodiment provides a slope repair method based on stone stacking. Compared with the first embodiment, the stone stacking route provided is more functional and has a better overall landscape effect.

[0072] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field are aware of all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement the scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A slope repair method based on stone stacking, characterized in that: The following steps are involved: Step 1: Collect basic slope data, and draw a slope profile structure diagram and a slope elevation structure diagram based on the basic slope data; Step 2, calculating the slope stability, and dividing the slope into protection area, repair area and reconstruction area according to the slope stability; Step 3: For the repair area and the reconstruction area, evaluate the stress environment of each area, select the area whose load conditions meet the base load standard as the base surface; select the area whose load conditions meet the transition load standard as the folding surface; connect the base surface and the folding surface in series to construct a stone stacking route; and install stones according to the stone stacking route; Step 4: Carry out vegetation ecological restoration in the protected areas.

2. A slope repair method based on stone stacking according to claim 1, characterized in that: In step 1, the basic slope data includes geological data and topographic data; the geological data includes rock and soil type, rock and soil layer, rock and soil structure, rock and soil physical and chemical properties and groundwater level; the topographic data includes contour lines, slope and slope direction.

3. A slope repair method based on stone stacking according to claim 1, characterized in that: In step 2, the finite element method is used to calculate the slope stability, and the slope is divided into protection area, repair area and reconstruction area according to the preset step threshold.

4. The slope repair method based on stone stacking according to claim 1, characterized in that: When installing stones according to the stone stacking route, first lay a steel frame along the stone stacking route, then process concrete retaining walls on the base surface and the folding surface as a primary retaining wall; then construct a planting trough on the base surface, and the planting trough is used to plant plants.

5. A slope repair method based on stone stacking according to claim 4, characterized in that: A secondary retaining wall is also constructed on the outer side surface of the primary retaining wall of the folded surface and the outer side surface of the planting trough; the secondary retaining wall is a plastic stone retaining wall.

6. A slope repair method based on stone stacking according to claim 5, characterized in that: The plastic stone retaining wall is arranged in a layer-by-layer construction manner; and adjacent layers of plastic stones are arranged in a staggered manner to form plastic stone steps.

7. The slope repair method based on stone stacking according to claim 1, characterized in that: When calculating the stone stacking route, a route analysis model is used to automatically generate the stone stacking route; a CNN-GNN joint network is arranged in the route analysis model; the CNN-GNN joint network includes an input layer, a CNN layer, an attention layer, a first fully connected layer, a GNN layer, a second fully connected layer and an output layer which are arranged in sequence; the CNN-GNN joint network takes a base surface, a folding surface, a slope profile structure diagram and a slope elevation structure diagram as inputs, takes a series connection of a base surface and a folding surface as a target, and takes a stone stacking route and a corresponding risk level as outputs.

8. The method for slope repair based on stone stacking according to claim 7, characterized in that: When calculating the stone stacking route, it also includes: when there are multiple stone stacking routes with equal risk levels, an auxiliary analysis model is used to screen the stone stacking routes; an LSTM network is provided in the auxiliary analysis model; the LSTM network is used to learn the surface runoff of the slope and predict the degree of influence of the surface runoff on each stone stacking route; and the stone stacking route with the lowest influence is selected.

9. The method for slope repair based on stone stacking according to claim 4, characterized in that: After the stone stacking route is constructed, the stone stacking route is also optimized; the optimization includes: setting benchmark stones; based on the benchmark stones, previewing the stone stacking route to obtain a preview rendering; based on the preview rendering, verifying the road slope; and screening out sections that do not meet the slope benchmark value, and modifying the primary retaining wall size and stone size of this section to balance the road slope.

10. The method for slope repair based on stone stacking according to claim 4, characterized in that: Step 4 also includes setting a drainage ditch above the slope; setting a drainage ditch in the slope and at the bottom of the slope; the drainage ditch is associated with the planting trough to form a U-shaped structure, the drainage ditch is located at the bottom of the U-shaped structure, and is used to collect and guide surface runoff; the planting trough is located on both sides of the U-shaped structure.

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