Water conservancy slope construction process for ecological restoration

Abstract

The application discloses a water conservancy slope construction process for ecological restoration, relates to the technical field of slope ecological restoration of water conservancy projects, and adjusts the slope of a river embankment through stacked stone cage net boxes; meanwhile, the net cage structure of the stone cage net box enables suspended matters and silt in water to be deposited in the gaps of the stone blocks, prevents excessive scouring of the silt, and, with the flexibility of the stone cage net, stabilizes the foundation to reduce uneven settlement of the foundation; further, an ecological concrete layer is cast in situ on the stone cage net box, and a geotechnical unit is laid on the ecological concrete layer; the three-layer impact resistance of porous bricks + the geotechnical unit + ecological concrete resists the scouring of water flow with a higher flow rate, meanwhile, nutrient soil fills the pores of the ecological concrete, the geotechnical unit solidifies the soil, and the plant root system can penetrate the ecological concrete and enter the stone cage net, so that the stability of the plants is strengthened; the process organically combines the flexibility of the stone cage net, the porosity of the ecological concrete, the soil solidification of the geotechnical unit and the rigidity of the porous bricks, and forms a composite slope protection system with layered defense.

Description

Technical Field

[0001] This invention relates to the field of ecological restoration technology for water conservancy engineering slopes, and in particular to a construction process for water conservancy slopes used for ecological restoration. Background Technology

[0002] In water conservancy projects such as rivers and reservoirs, traditional hard slope protection methods, such as concrete slopes and masonry slopes, can meet flood control safety requirements. However, because concrete blocks the exchange of water, soil, and air, soil organisms lose their living space, leading to a break in the ecological food chain. Hard slope protection severs the ecological connection between water and land, resulting in problems such as amphibians being unable to come ashore, plants being unable to take root, and a decline in the self-purification capacity of water bodies. To improve these situations, in recent years, the engineering community has begun to try using ecological slope protection technologies to restore or rebuild the ecological connection between water and land while ensuring the structural safety of the slope. These technologies typically alleviate the ecological defects of hard slope protection to some extent by introducing vegetation substrates, permeable components, or vegetation cover layers. However, due to limitations in material performance, structural design, and post-maintenance, the ecological slope protection technologies currently used in engineering projects still generally have many shortcomings.

[0003] Porous structure slope protection is a type of slope protection that uses porous bricks for planting grass. Common porous bricks include herringbone bricks and hexagonal grid slope protection bricks. Through its continuous porous structure, it provides a good living space and habitat for plants and animals, and has strong water circulation capacity and erosion resistance. However, because porous bricks are prone to sliding into the riverbed due to gravity, porous structure slope protection has limitations on the slope of the riverbank. Furthermore, the soil under the porous bricks is easily eroded by the river water, which can create depressions, causing the thin layer of porous bricks to loosen and be washed away. Summary of the Invention

[0004] In view of this, this application provides a construction technology for ecological restoration of hydraulic slopes. The slope of the riverbank is adjusted by stacking gabion cages. Simultaneously, the gabion cage structure allows suspended matter and silt in the water to be deposited in the gaps between the stones, preventing excessive erosion of sediment. The flexibility of the gabion mesh stabilizes the foundation and reduces uneven settlement. Furthermore, an ecological concrete layer is cast-in-place on the gabion cages, and geotechnical units are laid on top of this layer. This three-layer structure of porous bricks, geotechnical units, and ecological concrete resists the erosion of high-velocity water flows. Nutrient soil fills the pores of the ecological concrete, and the geotechnical units stabilize the soil. Plant roots can penetrate the ecological concrete and grow into the gabion mesh, enhancing plant stability. This technology organically combines the flexibility of gabion mesh, the porosity of ecological concrete, the soil-stabilizing properties of geotechnical units, and the rigidity of porous bricks, forming a layered composite slope protection system.

[0005] This application provides a construction technique for hydraulic slopes used in ecological restoration, the technique comprising the following steps:

[0006] A permeable geotextile is laid on the slope to be treated. A mixed layer of graded crushed stone and humus is laid on top of the permeable geotextile. Microbial agents and water-retaining agents are added to the mixed layer to obtain a bottom ecological interconnection layer. The overlap of the permeable geotextile is fixed with U-shaped nails.

[0007] A layer of gravel is laid on top of the bottom ecological connectivity layer to obtain a gravel leveling layer;

[0008] On the crushed stone leveling layer, gabion mesh boxes are installed layer by layer from the toe of the slope upwards. The upper and lower layers of gabion mesh boxes are fixed with connecting buckles. The gabion mesh boxes are filled with stones. The filling is carried out in two layers and slightly vibrated to compact the stones. The gabion mesh is stacked to form a gentle slope with a preset ratio.

[0009] Lay reverse filter geotextile on the surface of the already filled gabion mesh, with an overlap width of ≥30cm between adjacent widths;

[0010] A layer of ecological concrete is poured in place on the geotextile filter, and the ecological concrete has a porous structure.

[0011] After the ecological concrete has initially set, nutrient soil is filled into the pores of the ecological concrete.

[0012] After filling the ecological concrete surface with nutrient soil, a geotechnical unit is laid and fixed with anchor nails. Nutrient soil is then filled into the geotechnical unit and grass and shrub seeds are sprayed.

[0013] A thick layer of medium sand is laid on the surface of the geotechnical unit. Perforated bricks are then laid on the medium sand leveling layer, with a pre-set gap between the bricks. Nutrient soil is filled into the pores of the perforated bricks and grass seeds are sprayed on them.

[0014] Optionally, before laying the permeable geotextile on the slope to be treated, the following steps are also included:

[0015] The riverbank slope to be repaired is cleaned and leveled, a concrete toe protection base is poured at the toe of the slope, a capping concrete layer is poured at the top of the slope, and a water interception ditch is excavated inside the toe protection base at the toe of the slope to obtain the slope surface to be treated.

[0016] Optionally, the mesh size of the gabion box is 80×100mm, the wire diameter is 2.5-3.0mm, and the tensile strength is ≥380Mpa; the diameter of the stone is 80-150mm, and the mud content is <3%; the preset ratio is 1:1.5 to 1:2, where the preset ratio is the ratio of the vertical height of the slope to the horizontal distance.

[0017] Optionally, the permeable geotextile and the filter geotextile are made of polypropylene filament geotextile with a specification of 200-300g / m² and an overlap width of ≥20cm; the volume ratio of the graded crushed stone to the humus is 3:1; the microbial agent is EM bacteria, with an addition amount of 2kg per cubic meter; and the water-retaining agent is polyacrylamide, with an addition amount of 0.5kg per cubic meter.

[0018] Optionally, the eco-friendly concrete is prepared from crushed stone with a particle size of 10-20mm, cement, water and water-reducing agent, with a target porosity of 20-25% and a thickness of 10-15cm.

[0019] Optionally, the nutrient soil comprises humus, vermiculite, organic microbial coated slow-release fertilizer, and water-retaining agent; the ratio of humus, vermiculite, organic microbial coated slow-release fertilizer, and water-retaining agent is 60:20:15:5.

[0020] Optionally, the geotechnical unit is a geonet or a geocell; the geocell is made of polymer material, with a height of 10-15cm and a grid size of 30×30cm; the geonet is a three-dimensional vegetation net.

[0021] Optionally, the porous brick is a precast concrete porous brick with a compressive strength ≥10MPa. During paving, it is laid row by row from the toe of the slope upwards, with each row laid in a staggered manner.

[0022] Optionally, the foot protection base is 60cm wide and 80cm high; the capping concrete layer is 20cm thick and 80cm wide; the intercepting ditch is 40cm wide, 50cm deep, and has a slope of 2%.

[0023] Optionally, the particle size of the stone in the crushed stone leveling layer is 20-40mm, and the thickness of the crushed stone leveling layer is 5-10cm.

[0024] Compared to existing technologies, this application provides a construction process for ecological restoration of hydraulic slopes. The process involves adjusting the slope of the riverbank by stacking gabion cages. Simultaneously, the gabion cage structure allows suspended matter and silt in the water to be deposited in the gaps between the stones, preventing excessive erosion. The flexibility of the gabion mesh stabilizes the foundation and reduces uneven settlement. Furthermore, an ecological concrete layer is cast on top of the gabion cages, followed by the laying of geotechnical units. This three-layer structure of porous bricks, geotechnical units, and ecological concrete resists the erosion of high-velocity water flows. Nutrient soil fills the pores of the ecological concrete, and the geotechnical units stabilize the soil. Plant roots can penetrate the ecological concrete and anchor themselves in the gabion mesh, enhancing plant stability. This process organically combines the flexibility of gabion mesh, the porosity of ecological concrete, the soil-stabilizing properties of geotechnical units, and the rigidity of porous bricks, forming a layered, composite slope protection system. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0026] Figure 1 This is a flowchart illustrating the steps of the hydraulic slope construction process for ecological restoration proposed in this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0029] Figure 1 This is a flowchart illustrating the steps of the hydraulic slope construction process for ecological restoration proposed in this application, as shown in the embodiments. Figure 1 As shown, the steps include:

[0030] S11: Clean and level the riverbank slope to be repaired, pour a concrete toe protection base at the toe of the slope, pour a capping concrete layer at the top of the slope, and excavate a water interception ditch inside the toe protection base at the toe of the slope to obtain the slope surface to be treated.

[0031] The foot protection base is 60cm wide and 80cm high; the capping concrete layer is 20cm thick and 80cm wide; the intercepting ditch is 40cm wide, 50cm deep, and has a 2% slope.

[0032] The riverbank slope to be repaired needs to be cleaned and leveled. First, remove weeds, tree roots, loose soil, large stones, construction waste and organic matter from the slope. Use an excavator or manual labor to trim the slope to the designed slope. The slope should be flat and straight, without any local protrusions or depressions. The allowable deviation for flatness is ±5cm / 5m.

[0033] For localized depressions, use the same type of soil to backfill and compact in layers, with each layer having a loose thickness of ≤30cm and a compaction degree of ≥90%. After cleaning and leveling, pour a C20 concrete toe cap at the slope toe. The cap should be 60cm wide and 80cm high, with the top surface 20-30cm above the normal water level. Before pouring, excavate the foundation trench to the stable bearing layer, excavating at least 50cm downwards from the original ground level at the slope toe. After compacting the foundation, set up formwork, pour concrete, and vibrate it to ensure it is dense. Smooth the top surface. On the inner side of the cap, i.e., the side closest to the slope, reserve anchoring holes or connecting bars for connection with gabion mesh boxes.

[0034] Seven days after the slope protection base is cured, a capping concrete layer is poured at the top of the slope. The capping layer is 20cm thick and 80cm wide, using C20 concrete. Before pouring, the top of the slope is cleaned of loose soil, and formwork is erected. After pouring, the surface is smoothed and a 2% outward drainage slope is set. A stainless steel guardrail (1.2m high) is installed on the outside of the capping layer. Finally, a drainage ditch is excavated on the inner side of the slope protection base (the side closest to the slope). The drainage ditch is 40cm wide and 50cm deep, with a 2% slope towards the collection pool. The ditch walls and bottom are plastered with M10 cement mortar (2cm thick) or a geomembrane is laid for seepage prevention. The drainage ditch is arranged parallel to the slope protection base, and a drainage ditch cover is added to the top of the ditch. Precast concrete grating or cast iron grating can be used. The cover is flush with the top surface of the slope protection base, resulting in a slope with a stable base and drainage system.

[0035] After cleaning and leveling the slope surface, a toe retaining base is poured, and a capping concrete layer is applied at the top of the slope. The combined action of the toe retaining base and the capping concrete layer restrains longitudinal displacement of the slope, enhances overall anti-sliding stability, and prevents slope slippage. A drainage ditch is excavated inside the toe retaining base to divert rainwater flowing down the slope and prevent water accumulation inside the base.

[0036] S12: A permeable geotextile is laid on the slope to be treated. A mixed layer of graded crushed stone and humus is laid on top of the permeable geotextile. Microbial agents and water-retaining agents are added to the mixed layer to obtain a bottom ecological interconnection layer. The overlap of the permeable geotextile is fixed with U-shaped nails.

[0037] The permeable geotextile is made of polypropylene filament geotextile with a specification of 200-300g / m². The overlap width between two adjacent permeable geotextiles is ≥20cm, and the overlap is fixed with U-shaped nails to secure the permeable geotextile into the soil. The volume ratio of graded crushed stone to humus is 3:1. The thickness of the mixed layer of graded crushed stone and humus is 15cm. The mixed layer of graded crushed stone and humus is mixed with microbial inoculant and water-retaining agent. The microbial inoculant is EM bacteria, and the dosage is 2kg per cubic meter. The water-retaining agent is polyacrylamide, and the dosage is 0.5kg per cubic meter.

[0038] On the slope to be treated, lay a layer of polypropylene filament permeable geotextile with a specification of 200g / m². When laying, spread it from the top of the slope to the bottom, with an overlap width of not less than 20cm between adjacent geotextiles. The overlap direction is with the upper geotextile overlapping the lower geotextile (in the direction of water flow). Use U-shaped nails at the overlap. The U-shaped nails are made of φ6-8mm steel bars, 20-30cm long, and penetrate the geotextile into the soil of the slope below. The U-shaped nails are spaced 50-100cm apart and arranged in a quincunx pattern along the overlap line to ensure that the geotextile is tightly attached to the slope surface without wrinkles or gaps.

[0039] After the permeable geotextile is laid, a mixed layer of graded crushed stone and humus is laid on top of the permeable geotextile. The mixed layer is prepared with a crushed stone to humus volume ratio of 3:1 at room temperature. The graded crushed stone has a particle size of 20-40mm, and the humus is fertile topsoil with a decomposed organic matter content of ≥30%.

[0040] First, mix the graded crushed stone and humus evenly using a mixer or manually, then spread it evenly on the permeable geotextile to a thickness of 15cm (after compaction). During the spreading process, add 2kg of EM microbial agent and 0.5kg of polyacrylamide water-retaining agent per cubic meter of the mixed layer. The agent and water-retaining agent can be mixed with a small amount of water to form a slurry, sprayed evenly on the surface of the mixed layer, and then mixed evenly with the mixed layer, or they can be mixed in by layering and mixing. After the mixed layer is laid, compact it 1-2 times with a light roller or plate vibrator, controlling the surface flatness to ±2cm / 2m, forming a bottom ecological interconnected layer.

[0041] Permeable geotextiles allow for the bidirectional migration of water, air, microorganisms, and soil animals (such as earthworms) between the original slope and the superstructure. Simultaneously, the mixed layer of gravel and humus has good porosity. Therefore, utilizing the bottom ecological layer as an intermediate layer achieves physical transition, hydraulic connectivity, and ecological connectivity between the slope to be treated and the gabion cages. On the other hand, the humus, rich in organic matter, provides long-term nutrients for seedlings and microorganisms planted in the upper ecological concrete layer. The water-retaining agent (polyacrylamide) can absorb hundreds of times its own weight in water, releasing it slowly during droughts to reduce irrigation needs. EM bacteria accelerate the decomposition of organic matter, improve soil aggregate structure, inhibit pathogens, and promote healthy root development.

[0042] S13: Lay a layer of gravel above the bottom ecological connectivity layer to obtain a gravel leveling layer.

[0043] The particle size of the stone in the crushed stone leveling layer is 20-40mm, and the thickness of the crushed stone leveling layer is 5-10cm.

[0044] The crushed stone leveling layer creates a smooth, permeable, and buffered transition interface between the bottom ecological connectivity layer and the gabion cages. It provides stable support for the gabion cages upwards and protects the ecological connectivity layer and permeable geotextile downwards, preventing the loss of fine particles and ensuring the overall stability and long-term durability of the slope structure.

[0045] S14: On the gravel leveling layer, gabion mesh boxes are installed layer by layer from the toe of the slope upwards. The upper and lower layers of gabion mesh boxes are fixed with connecting buckles. The gabion mesh boxes are filled with stones. The filling is carried out in two layers and slightly vibrated to compact the stones. The gabion mesh is stacked to form a gentle slope with a preset ratio.

[0046] The gabion mesh has a mesh size of 80×100mm, a wire diameter of 2.5-3.0mm, and a tensile strength ≥380Mpa; the stones have a diameter of 80-150mm and a mud content of <3%; the preset ratio is 1:1.5 to 1:2, where the preset ratio is the ratio of the vertical height to the horizontal distance of the slope. The gabion mesh is assembled from galvanized and plastic-coated steel wire mesh, and adjacent gabion meshes are connected by binding wire.

[0047] On the completed gravel leveling layer, gabion cages are installed layer by layer from the toe of the slope upwards. First, galvanized plastic-coated steel wire mesh (mesh size 80×100mm, wire diameter 2.5-3.0mm, tensile strength ≥380MPa) is unfolded according to the design dimensions. The adjacent edges of the mesh are securely tied with spiral binding wire, with the binding points spaced no more than 20cm apart, forming open gabion cages. The first layer of cages is placed tightly against the inner side of the slope toe protection base, with the bottom of the cages in close contact with the gravel leveling layer. Adjacent cages are connected to each other with binding wire to form a whole. Then fill the gabion cage with stones (80-150mm in diameter, mud content <3%), filling in layers: first fill to half the height of the gabion cage, using manual labor or small machinery to place large stones along the edges and small stones in the center, lightly compacting the stones with a wooden mallet or light vibrator; then continue filling until the top of the gabion cage is 2-3cm higher (to allow for settlement space), and lightly compact again to ensure uniform spacing between stones and no voids. After filling, close and secure the gabion cage cover. After the first layer of gabion cages is completely filled and sealed, install the second layer of gabion cages on top of it. The second layer of gabion cages is fixed to the first layer with connecting buckles or figure-eight binding wire, with the connection points spaced no more than 50cm apart, and the upper and lower layers of gabion cages are staggered, meaning the seams of the upper layer are not aligned with the seams of the lower layer. Install the gabion mesh layer by layer, filling each layer with stones as described above, and controlling the retreat distance of each layer to create a gentle slope with a pre-set ratio of 1:1.5 to 1:2. During construction, use a spirit level and slope gauge to check the slope constantly and make timely adjustments to ensure a smooth and consistent slope.

[0048] By stacking gabion cages in different ways and adjusting the slope ratio to the range of {1:1.5, 1:2}, the gabion cages can adapt to foundation deformation and resist water erosion, while also providing space for the roots of vegetation to extend. This is a key structural layer for achieving synergy between engineering safety and ecological restoration.

[0049] S15: Lay reverse filter geotextile on the surface of the already filled gabion mesh, with an overlap width of ≥30cm between adjacent widths.

[0050] The geotextile is fixed to the surface of the gabion mesh by being covered by an upper layer of ecological concrete. Laying the geotextile on the surface of the gabion mesh prevents the nutrient soil in the pores of the upper ecological concrete layer from leaking down and losing, ensuring the long-term stability of the vegetation growth substrate, while separating the large-diameter stones (80-150mm) in the gabion mesh from the small-diameter crushed stone aggregate (10-20mm) in the ecological concrete.

[0051] S16: A layer of ecological concrete is poured on the geotextile filter, and the ecological concrete has a porous structure.

[0052] The eco-concrete is prepared from crushed stone with a particle size of 10-20mm, cement, water, and a water-reducing agent, with a target porosity of 20-25% and a thickness of 10-15cm. Porosity refers to the percentage of the volume of pores inside the eco-concrete to the total volume of the eco-concrete.

[0053] One example shows the preparation of crushed stone, cement, water, and water-reducing agent including:

[0054] Crushed stone (10-20mm): 1500 kg, cement (42.5 grade): 300 kg, water: 75 kg, water-reducing agent: 3 kg;

[0055] Crushed stone (10-20mm): 1450 kg, cement (42.5 grade): 260 kg, water: 65 kg, water-reducing agent: 2.5 kg.

[0056] S17: After the initial setting of the ecological concrete, fill the pores of the ecological concrete with nutrient soil.

[0057] The nutrient soil consists of humus, vermiculite, organic microbial coated slow-release fertilizer, and water-retaining agent; the ratio of humus, vermiculite, organic microbial coated slow-release fertilizer, and water-retaining agent is 60:20:15:5.

[0058] Materials to be prepared: crushed stone with a particle size of 10-20mm, PO 42.5 ordinary silicate cement, polycarboxylate superplasticizer, clean fresh water, humus:vermiculite:organic slow-release fertilizer:water-retaining agent = 60:20:15:5 (volume ratio); mix the above materials evenly, and control the moisture content at 15-20%.

[0059] The mix design uses only 10-20mm continuously graded crushed stone, without adding any sand. The gaps between the stones are not filled, naturally forming interconnected pores. The cement content is controlled at 260-320kg per cubic meter, ensuring the cement slurry only coats the surface of the crushed stone and does not flow and fill the pores. The water-cement ratio is controlled at 0.25-0.35, resulting in a thick slurry to prevent it from becoming too thin and flowing and clogging the pores. Vibrators are used at 30-40cm intervals, for 5-10 seconds per point, stopping when the cement slurry rises to the surface. The vibrators should not touch the geotextile fabric laid on the surface of the gabion cages to avoid the cement slurry settling due to excessive vibration, which could clog the bottom and internal pores. A wooden trowel is used to smooth the surface to a matte finish, preventing the formation of a sealed layer of cement slurry and ensuring open surface pores. After obtaining the porous concrete structure, nutrient soil is filled into the pores of the ecological concrete, with a filling rate ≥80%, resulting in an ecological concrete layer.

[0060] S18: After filling the ecological concrete surface with nutrient soil, lay geotechnical units, fix them with anchors, fill the geotechnical units with nutrient soil, and spray grass and shrub seeds.

[0061] The geotechnical unit is a geonet or geocell; the geocell is made of polymer material, 10-15cm high, with a grid size of 30×30cm; the geonet is a three-dimensional vegetation net. The geocells or geonet form a three-dimensional grid structure to prevent rainwater runoff from washing away the soil in the ecological concrete through the gaps.

[0062] The above steps yield porous concrete. Nutrient soil is then filled into the pores of the ecological concrete. Geotechnical units are used to form a three-dimensional constraint on the surface nutrient soil, creating a composite layer of ecological concrete, nutrient soil, geotechnical units, and vegetation. This achieves a four-in-one system of "concrete skeleton resisting erosion, nutrient soil supplying water, geotechnical units stabilizing soil, and vegetation root anchoring," ensuring both slope structural stability and providing a superior growth environment for plants.

[0063] S19: Lay a thick layer of medium sand on the surface of the geotechnical unit, lay porous bricks on the medium sand leveling layer, leave a pre-set gap between the bricks, fill the pores of the porous bricks with nutrient soil and spray grass seeds.

[0064] The porous bricks are precast concrete porous bricks with a compressive strength ≥10MPa. During installation, they are laid row by row from the toe of the slope upwards, with staggered joints in each row. The medium sand leveling layer is 2-3cm thick.

[0065] A 2-3cm thick layer of medium sand is laid on the surface of the geotechnical unit (geogrid or geocell). The medium sand should have a particle size of 0.5-2mm and a mud content of <3%. During laying, a screed is used to level the surface along the slope to fill any unevenness on the geotechnical unit surface, thus providing a flat and uniform paving base for the porous bricks. Then, starting from the toe of the slope, precast concrete porous bricks (compressive strength ≥10MPa) are laid row by row upwards. A 5-10mm gap is left between each row of bricks, and they are laid in a staggered pattern. During installation, a rubber mallet is used to gently tap the brick surface to embed it into the medium sand layer and maintain a flat surface. The height difference between adjacent bricks is controlled within 5mm. After the porous bricks are laid, nutrient soil (a mixture of humus, vermiculite, slow-release organic fertilizer, and water-retaining agent in a volume ratio of 60:20:15:5) is filled into the pores of the bricks and the gaps between the bricks, with a compaction degree of ≥80%. Finally, grass and shrub seeds are sprayed onto the surface of the pores (hydraulic spraying or manual sowing can be used). After spraying, the surface is covered with non-woven fabric to retain moisture for 7-14 days until the seeds germinate and sprout. This step disperses the pressure of the bricks and protects the underlying geotechnical units through the medium sand leveling layer, enhances the slope's erosion resistance through the rigid surface layer of the porous bricks, and provides a growth substrate for plants through the nutrient soil in the brick joints and pores, thus combining rigid surfacing with ecological greening.

[0066] The aforementioned construction technique for ecological restoration of water conservancy slopes adjusts the slope of riverbanks by stacking gabion cages. Simultaneously, the gabion cage structure allows suspended matter and silt in the water to be deposited in the gaps between the stones, preventing excessive erosion. The flexibility of the gabion mesh stabilizes the foundation and reduces uneven settlement. Furthermore, an ecological concrete layer is cast on top of the gabion cages, followed by geotechnical units. This three-layer structure of porous bricks, geotechnical units, and ecological concrete resists the erosion of high-velocity water flows. Nutrient soil fills the pores of the ecological concrete, and the geotechnical units stabilize the soil. Plant roots can penetrate the ecological concrete and anchor themselves in the gabion mesh, enhancing plant stability. This technique organically combines the flexibility of gabion mesh, the porosity of ecological concrete, the soil-stabilizing properties of geotechnical units, and the rigidity of porous bricks, forming a composite slope protection system that is both flexible and rigid, with layered protection.

[0067] In another water conservancy slope construction technique for ecological restoration proposed in this application embodiment, moisture-tolerant plants are planted in the water-near area where the retaining base is located. The water-near area is from the foot of the slope to 1 / 3 of the slope height, and the moisture-tolerant plants planted include reeds, calamus, and canna lilies; the middle slope area is from 1 / 3 to 2 / 3 of the slope height, and the shrubs and grasses planted include Amorpha fruticosa, Lespedeza bicolor, Hippophae rhamnoides, and Zoysia japonica; the trees and climbing plants planted in the upper slope area and at the top of the slope include Sapium sebiferum, wisteria, and Virginia creeper.

[0068] Plant moisture-tolerant plants in the water-prone area, combine shrubs and grasses in the middle slope area, and plant native trees and climbing plants in the upper slope area and on the top of the slope; use an intelligent irrigation system to water and maintain the plants as needed until the plant community is self-sustaining.

[0069] Another construction technique for water conservancy slopes for ecological restoration proposed in this application may include the following steps:

[0070] S20: Clean and level the riverbank slope to be repaired, pour a concrete toe protection base at the toe of the slope, pour a capping concrete layer at the top of the slope, and excavate a water interception ditch inside the toe protection base at the toe of the slope to obtain the slope surface to be treated.

[0071] S21: A permeable geotextile is laid on the slope to be treated. A mixed layer of graded crushed stone and humus is laid on top of the permeable geotextile. Microbial agents and water-retaining agents are added to the mixed layer to obtain a bottom ecological interconnection layer. The overlap of the permeable geotextile is fixed with U-shaped nails.

[0072] S22: Lay a layer of gravel above the bottom ecological connectivity layer to obtain a gravel leveling layer.

[0073] S23: On the gravel leveling layer, gabion mesh boxes are installed layer by layer from the toe of the slope upwards. The upper and lower layers of gabion mesh boxes are fixed with connecting buckles. The gabion mesh boxes are filled with stones. The filling is carried out in two layers and slightly vibrated to compact the stones. The gabion mesh is stacked to form a gentle slope with a preset ratio.

[0074] S24: Lay reverse filter geotextile on the surface of the already filled gabion mesh, with an overlap width of ≥30cm between adjacent widths.

[0075] S25: A layer of ecological concrete is poured on the geotextile filter, and the ecological concrete has a porous structure.

[0076] S26: After the initial setting of the ecological concrete, fill the pores of the ecological concrete with nutrient soil.

[0077] S27: After filling the ecological concrete surface with nutrient soil, lay geotechnical units, fix them with anchors, fill the geotechnical units with nutrient soil, and spray grass and shrub seeds.

[0078] S28: Lay a thick layer of medium sand on the surface of the geotechnical unit, lay porous bricks on the medium sand leveling layer, leave a pre-set gap between the bricks, fill the pores of the porous bricks with nutrient soil and spray grass seeds.

[0079] S29: In the porous brick area, set up a brick-free vegetation strip every 10-20m. The width of the vegetation strip can be 30-50cm to allow amphibians to crawl ashore.

[0080] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computing software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0081] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0082] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A construction technique for hydraulic slopes used in ecological restoration, characterized in that, The process includes the following steps: A permeable geotextile is laid on the slope to be treated. A mixed layer of graded crushed stone and humus is laid on top of the permeable geotextile. Microbial agents and water-retaining agents are added to the mixed layer to obtain a bottom ecological interconnection layer. The overlap of the permeable geotextile is fixed with U-shaped nails. A layer of gravel is laid on top of the bottom ecological connectivity layer to obtain a gravel leveling layer; On the crushed stone leveling layer, gabion mesh boxes are installed layer by layer from the toe of the slope upwards. The upper and lower layers of gabion mesh boxes are fixed with connecting buckles. The gabion mesh boxes are filled with stones. The filling is carried out in two layers and slightly vibrated to compact the stones. The gabion mesh is stacked to form a gentle slope with a preset ratio. Lay reverse filter geotextile on the surface of the already filled gabion mesh, with an overlap width of ≥30cm between adjacent widths; A layer of ecological concrete is poured in place on the geotextile filter, and the ecological concrete has a porous structure. After the ecological concrete has initially set, nutrient soil is filled into the pores of the ecological concrete. After filling the ecological concrete surface with nutrient soil, a geotechnical unit is laid and fixed with anchor nails. Nutrient soil is then filled into the geotechnical unit and grass and shrub seeds are sprayed. A thick layer of medium sand is laid on the surface of the geotechnical unit. Perforated bricks are then laid on the medium sand leveling layer, with a pre-set gap between the bricks. Nutrient soil is filled into the pores of the perforated bricks and grass seeds are sprayed on them.

2. The process according to claim 1, characterized in that, Before laying permeable geotextile on the slope to be treated, the following steps are also included: The riverbank slope to be repaired is cleaned and leveled, a concrete toe protection base is poured at the toe of the slope, a capping concrete layer is poured at the top of the slope, and a water interception ditch is excavated inside the toe protection base at the toe of the slope to obtain the slope surface to be treated.

3. The process according to claim 1, characterized in that, The gabion mesh has a mesh size of 80×100mm, a wire diameter of 2.5-3.0mm, and a tensile strength ≥380Mpa; the stones have a diameter of 80-150mm and a mud content of <3%; the preset ratio is 1:1.5 to 1:2, where the preset ratio is the ratio of the vertical height of the slope to the horizontal distance.

4. The process according to claim 1, characterized in that, The permeable geotextile and the filter geotextile are made of polypropylene filament geotextile with a specification of 200-300g / m² and an overlap width of ≥20cm; the volume ratio of the graded crushed stone to the humus is 3:1; the microbial agent is EM bacteria, with an addition amount of 2kg per cubic meter; the water-retaining agent is polyacrylamide, with an addition amount of 0.5kg per cubic meter.

5. The process according to claim 1, characterized in that, The ecological concrete is made of crushed stone with a particle size of 10-20mm, cement, water and water-reducing agent, with a target porosity of 20-25% and a thickness of 10-15cm.

6. The process according to claim 1, characterized in that, The nutrient soil consists of humus, vermiculite, organic microbial coated slow-release fertilizer, and water-retaining agent; the ratio of humus, vermiculite, organic microbial coated slow-release fertilizer, and water-retaining agent is 60:20:15:

5.

7. The process according to claim 1, characterized in that, The geotechnical unit is a geonet or geocell; the geocell is made of polymer material, with a height of 10-15cm and a grid size of 30×30cm; the geonet is a three-dimensional vegetation net.

8. The process according to claim 1, characterized in that, The porous bricks are precast concrete porous bricks with a compressive strength ≥10MPa. During paving, they are laid row by row from the toe of the slope upwards, with each row laid in a staggered manner.

9. The process according to claim 2, characterized in that, The foot protection base is 60cm wide and 80cm high; the capping concrete layer is 20cm thick and 80cm wide; the intercepting ditch is 40cm wide, 50cm deep, and has a 2% slope.

10. The process according to claim 1, characterized in that, The particle size of the stone in the crushed stone leveling layer is 20-40mm, and the thickness of the crushed stone leveling layer is 5-10cm.

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