Ice-rush-resistant stepped sediment control and protection slope structure

Abstract

The application discloses an anti-ice-rush scouring gradient silt control and protection slope structure and relates to the technical field of ecological protection slope engineering. The application discloses an anti-ice-rush scouring gradient silt control and protection slope structure and relates to the technical field of ecological protection slope engineering. The slope top runoff dispersion and energy dissipation zone comprises blind ditches which are arranged close to the slope top and parallel to the river course and a drop retaining wall which is arranged on the side of the blind ditch far from the slope top. The slope foot anti-ice-rush scouring flexible foundation protection zone comprises a stone cage net mat which is arranged on the side of the slope foot far from the slope top and a water-following willow branch row which is arranged on the stone cage net mat and / or the river course. The water-following willow branch row extends along the river course. Through the arrangement of the slope top runoff dispersion and energy dissipation zone, the slope surface gradient silt control and plant overwintering zone and the slope foot anti-ice-rush scouring flexible foundation protection zone, the stability of the bank slope under the combined action of freezing and thawing, runoff and ice is improved, and the phenomenon of water and soil loss is effectively avoided.

Description

Technical Field

[0001] This invention relates to the field of ecological slope protection engineering technology, specifically to a stepped silt control slope protection structure that resists ice erosion. Background Technology

[0002] The methods for riverbank protection in high-altitude and cold regions have evolved continuously, progressing from passive erosion under natural conditions, to traditional hardened slope protection mainly using masonry and concrete retaining walls, and finally to conventional ecological slope protection methods such as sowing grass seeds and laying geonets, which have been widely adopted in recent years. Currently, in the process of ecological governance in the Qinghai-Tibet Plateau basin, environmental protection standards are becoming increasingly stringent. Traditional hardened slope protection, due to its obstruction of water and soil exchange and poor visual appeal, has been gradually restricted, and various flexible ecological protection technologies have begun to be promoted. However, constrained by the unique climate and hydrological characteristics of the Qinghai-Tibet Plateau, existing conventional ecological slope protection technologies have revealed significant inadequacies in engineering practice, with most projects experiencing structural failure or functional loss after a single winter-spring cycle.

[0003] Specifically, existing technologies have the following four main limitations and shortcomings: 1. Rigid and semi-rigid structures have poor resistance to frost heave and thaw settlement. Existing masonry and ecological retaining walls with concrete foundations are mostly rigid or semi-rigid. In high-altitude and cold regions with drastic diurnal and seasonal temperature differences, soil moisture undergoes intense deformation during the winter's freezing and expansion and the spring's thawing and contraction. Rigid protective structures, lacking adaptability to deformation, are highly susceptible to widespread cracking, tilting, and collapse.

[0004] 2. The slope toe lacks flexible protection against icing erosion and cutting. During the transition from winter to spring or the spring ice jam season, large amounts of ice often flow down into cold river channels with rapid currents. While conventional techniques such as vegetation nets or Reno mattresses can resist water erosion to some extent, they are easily damaged and torn when faced with the mechanical impact and cutting force of ice shards with enormous kinetic energy. Once the foundation at the toe of the slope is hollowed out by ice shards, it will directly lead to the overall instability and collapse of the upper bank slope.

[0005] 3. The lack of stepped sand-blocking structures on the slope exacerbates soil erosion. During the flood season, rainfall is concentrated and surface runoff is fast, making it difficult for existing single-layer net mats to effectively reduce water flow shear force. Especially in the early stages of vegetation establishment, when the root system has not yet taken deep root to stabilize the soil, surface runoff with high sediment load can easily carry topsoil, plant seeds, and seedlings into the river, resulting in the failure of the ecological interception function.

[0006] 4. Extreme low temperatures and strong winds result in low overwintering survival rates for plants. In high-altitude and cold regions, winters are often accompanied by extremely low temperatures and strong winds. Traditional methods typically involve planting plants at the same elevation as the slope, leaving the root collars and overwintering buds of seedlings completely exposed to the cold winds. This planting method easily leads to physiological drying and frost damage in the plants, significantly reducing the greening rate in the following spring and ultimately causing severe degradation of the ecological slope protection effect.

[0007] Therefore, the development and design of tiered sediment control slope protection structures to resist ice erosion, achieve tiered flow and sediment control and avoid ice erosion, and thus prevent soil erosion, is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] To address the aforementioned problems, this invention provides a stepped sediment control slope protection structure that resists ice erosion, thereby achieving stepped flow and sediment control and preventing ice erosion, thus avoiding soil and water loss.

[0009] To achieve the above objectives, the present invention provides the following solution: A stepped sediment control slope protection structure for resisting ice erosion includes a runoff dispersion and energy dissipation zone at the top of the slope, a stepped sand-blocking and overwintering vegetation zone on the slope surface for planting vegetation, and a flexible base protection zone at the bottom of the slope to resist ice erosion, arranged sequentially from the top of the slope to the bottom of the slope. The runoff dispersion and energy dissipation zone at the top of the slope includes a blind ditch opened near the top of the slope and parallel to the direction of the river channel, and a drop retaining wall set on the side of the blind ditch away from the top of the slope. The flexible base protection zone at the bottom of the slope to resist ice erosion includes a gabion mattress set on the side of the bottom of the slope away from the top of the slope, and a row of willow branches set on the gabion mattress and / or the river channel, the row of willow branches extending along the direction of the river channel.

[0010] Preferably, the blind drain is lined with gravel, which is wrapped with permeable geotextile.

[0011] Preferably, the height of the crushed stone is lower than the height of the slope crest, and the height of the cascading retaining wall is higher than the height of the crushed stone and the height of the slope terrace sand-blocking and vegetation overwintering zone.

[0012] Preferably, the slope terrace sand-blocking and vegetation overwintering zone includes multiple three-dimensional geocells arranged in a honeycomb pattern, sinking troughs arrayed within the three-dimensional geocells, and vegetation planted within the sinking troughs. The sinking troughs are spaced one to three times apart. The bottom of the sinking troughs and the three-dimensional geocells are provided with through holes. The sinking troughs and the three-dimensional geocells are lined with a permeable gravel layer and a nutrient-rich soil layer from bottom to top.

[0013] Preferably, the sinking trough has an inverted conical structure, and the height of the sinking trough is lower than the height of the three-dimensional geocell.

[0014] Preferably, the height of the sinking trough is lower than the height of the nutrient-rich soil layer inside the three-dimensional geocell.

[0015] Preferably, the sinking trough is filled with a thermal insulation matrix.

[0016] Preferably, the gabion mattress includes a bottom gabion mattress and an upper gabion mattress disposed above the bottom gabion mattress. The bottom gabion mattress and the upper gabion mattress are arranged in a stepped manner. One side of the bottom gabion mattress and the upper gabion mattress abuts against the toe of the slope, and the other side of the bottom gabion mattress and the upper gabion mattress extends toward the river channel.

[0017] Preferably, the downstream willow branch raft is disposed on the upper surface of the upper gabion mattress and the upper surface of the lower gabion mattress, and the downstream willow branch raft is also disposed on the river channel in close contact with the side wall of the lower gabion mattress.

[0018] Preferably, the height of the willow branch raft near the upstream end of the water flow is higher than the height of the willow branch raft away from the upstream end of the water flow.

[0019] The present invention achieves the following technical effects compared to the prior art: Through the synergistic effect of the runoff dispersion and energy dissipation zone at the top of the slope, the tiered sand-blocking and overwintering vegetation zone on the slope surface, and the flexible base protection zone at the toe to resist ice erosion, the stability of the bank slope under the combined effects of freeze-thaw cycles, runoff, and ice is significantly improved. The blind ditch and cascade retaining wall at the top of the slope guide the destructive concentrated runoff that gathers at the top of the slope into the blind ditch and transforms it into underground flow. The overflowing surface runoff has a sharp drop in velocity under the physical obstruction of the cascade retaining wall, and is eventually transformed into a uniform thin layer of diffuse flow that is discharged downwards, which greatly reduces the initial scouring kinetic energy of the slope runoff and reduces source erosion. The tiered vegetation zone on the slope surface intercepts sediment and promotes deposition. The combined structure of gabion mattresses and willow branches at the toe of the slope weakens the scouring and erosion of the toe of the slope by ice and water flow through flexible buffering and diversion, enhances the overall ice and erosion resistance of the slope protection, and takes into account both ecological and engineering durability, effectively avoiding soil erosion. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Appendix Figure 1 This is a schematic diagram of the overall structure of the stepped sediment control slope protection structure for resisting ice erosion disclosed in this invention. Appendix Figure 2This is a schematic diagram of the overall structure of the sinking trough and three-dimensional geocell in the tiered sediment control slope protection structure for ice erosion resistance disclosed in this invention. Appendix Figure 3 This is a schematic diagram of the internal structure of the sinking trough in the stepped sediment control slope protection structure for resisting ice erosion disclosed in this invention. Among them, 1. Slope top; 2. Blind drain; 3. Gravel; 4. Waterfall retaining wall; 5. Slope surface; 6. Sinking trough; 7. Permeable gravel layer; 8. Nutrient-rich soil layer; 9. Vegetation; 10. Slope toe; 11. Upper gabion mattress; 12. Bottom gabion mattress; 13. Anchor bolt; 14. Flow-through willow branch trough; 15. River channel; 16. Three-dimensional geocell; 17. Thermal insulation matrix. Detailed Implementation

[0022] 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 embodiments of the present invention, and not all embodiments. Based on the 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.

[0023] The purpose of this invention is to provide a stepped sediment control slope protection structure that resists ice erosion, thereby achieving stepped flow and sediment control and preventing ice erosion, thus avoiding soil and water loss.

[0024] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] refer to Figure 1The tiered sediment control slope protection structure for ice erosion disclosed in this embodiment of the invention includes at least a slope top runoff dispersion and energy dissipation zone, a slope surface tiered sand-blocking and vegetation overwintering zone for planting vegetation 9, and a slope toe ice erosion-resistant flexible base protection zone arranged sequentially from the slope top 1 to the slope toe 10. The slope surface tiered sand-blocking and vegetation overwintering zone is set on the slope surface 5. The slope top runoff dispersion and energy dissipation zone includes a blind ditch 2 opened near the slope top 1. The blind ditch 2 is opened parallel to the direction of the river channel 15. A drop retaining wall 4 is set on the side of the blind ditch 2 away from the slope top 1. The direction of the drop retaining wall 4 is consistent with the direction of the blind ditch 2. The drop retaining wall 4 is used to physically block the runoff entering the blind ditch 2 and reduce the runoff velocity. The slope toe ice erosion-resistant flexible base protection zone includes a gabion mattress set on the side of the slope toe 10 away from the slope top 1, and a downstream willow branch raft 14 set on the gabion mattress and / or the river channel 15. The downstream willow branch raft 14 is arranged along the... The extension of the river channel 15, through the synergistic effect of the runoff dispersion and energy dissipation zone at the top of the slope, the tiered sand-blocking and overwintering vegetation zone on the slope surface, and the flexible base protection zone at the foot of the slope to resist ice erosion, significantly improves the stability of the bank slope under the combined effects of freeze-thaw, runoff, and ice. The blind ditch 2 and the cascading retaining wall 4 at the top of the slope 1 guide the destructive concentrated runoff gathered at the top of the slope 1 into the blind ditch 2 and turn it into underground flow. The overflowing surface runoff has a sharp drop in velocity under the physical obstruction of the cascading retaining wall 4, and finally transforms into a uniform thin layer of overflow to discharge downwards, which greatly reduces the initial scouring kinetic energy of the slope runoff and reduces source erosion. The tiered vegetation zone 9 on the slope surface intercepts sediment and promotes deposition. The combined structure of gabion mattresses and willow branches at the foot of the slope 14 weakens the scouring and erosion of the foot of the slope 10 by ice and water flow through flexible buffering and diversion, enhances the overall ice and erosion resistance of the slope protection, and takes into account ecological and engineering durability, effectively avoiding soil erosion.

[0026] It should be noted that the drop retaining wall 4 is constructed by piling up the soil excavated from the blind ditch 2, or by piling up a concrete layer around the soil. This not only achieves on-site disposal and resource utilization of the excavated soil, reducing the cost of transportation and landfill, but also enhances the obstruction and dispersion effect on runoff through the stepped or rough surface formed by the piling, reducing the flow velocity and erosion energy. At the same time, the introduction of the concrete layer can improve the structural durability and erosion resistance of the retaining wall, adapting to the long-term service requirements under high-altitude or high-flow conditions. Thus, while ensuring efficient energy dissipation of runoff at the top of the slope, it also takes into account economy, construction convenience and ecological adaptability.

[0027] refer to Figure 1In one embodiment, large-diameter crushed stone 3 is laid inside the blind ditch 2. The crushed stone 3 is wrapped in permeable geotextile and laid inside the blind ditch 2. On the one hand, the pores between the crushed stone 3 form an efficient drainage channel, which can quickly guide the runoff from the top of the slope 1 to infiltrate and discharge to the side or downstream, avoiding the accumulation of runoff on the slope surface and forming concentrated scouring. On the other hand, the permeable geotextile acts as a filter, which can effectively prevent fine soil particles from entering the crushed stone 3 layer with the water flow and being lost, preventing the blind ditch 2 from being blocked, while maintaining the long-term permeability and drainage capacity of the structure. In addition, the combination of large-diameter crushed stone 3 and geotextile can also buffer the runoff impact and evenly disperse the kinetic energy of the water flow, further improving the runoff energy dissipation effect, extending the service life of the blind ditch 2 and the entire runoff dispersion and energy dissipation zone at the top of the slope, and the construction is simple, the cost is controllable, and it is easy to promote and apply.

[0028] It should be noted that the particle size of the crushed stone 3 is 5cm to 15cm, preferably 8cm to 12cm.

[0029] refer to Figure 1 In one implementation method, the height of the gravel 3 is lower than the height of the slope crest 1, while the height of the cascading retaining wall 4 is higher than the height of the gravel 3 and the height of the slope terraces for sand control and the overwintering zone of vegetation. First, the lower gravel layer ensures that the runoff can quickly infiltrate and be channeled into the blind ditch 2 for drainage, avoiding excessive water level and flooding. Second, the protruding cascading retaining wall 4, as a key energy dissipation barrier, can effectively intercept and retain surface runoff from the slope crest 1 and above, forcing it to slow down, disperse, and cascade, significantly reducing the kinetic energy and erosion carrying capacity of the water. At the same time, the design of the retaining wall being higher than the vegetation zone can prevent high-speed runoff from directly scouring the root zone of the plants, providing a stable site environment for the slope vegetation 9, ensuring the integrity of the overwintering zone of vegetation and the restoration of ecological functions. In addition, this elevation combination can also use the physical shielding of the retaining wall to buffer the direct pushing and erosion of ice on the slope and gravel layer during the ice season or freeze-thaw conditions, thereby comprehensively improving the drainage, energy dissipation, erosion prevention, and ice resistance capabilities of the slope protection structure.

[0030] refer to Figure 2 and Figure 3As a preferred approach, the slope terraced sand-blocking and vegetation overwintering zone includes multiple three-dimensional geocells 16 arranged in a honeycomb pattern. Sinking troughs 6 are arrayed within each of the three-dimensional geocells 16, and vegetation 9 is planted within each sinking trough 6. Adjacent sinking troughs 6 are spaced 1-3 times apart. Through holes are provided at the bottom of the sinking troughs 6 and the three-dimensional geocells 16. A permeable gravel layer 7 and a nutrient-rich soil layer 8 are laid sequentially from bottom to top within both the sinking troughs 6 and the three-dimensional geocells 16. The sinking troughs 6 are spaced 1-3 times apart, ensuring both an orderly runoff path and sediment deposition space on the slope while avoiding excessively dense excavation. The impact on the overall stability of the grid cells; the through holes connect the sinking trough 6 to the bottom of the grid cells, promoting the free exchange and slow infiltration of water in the longitudinal profile, enhancing the slope's water retention capacity, and preventing saturation sliding; the lower permeable gravel layer 7 provides drainage and ventilation channels, accelerating the drainage of slope infiltration and preventing soil water accumulation and frost heave; the upper nutrient-rich soil layer 8 creates a stable substrate environment for the growth of vegetation 9 and the survival of overwintering buds. Overall, it significantly improves the slope's efficiency in intercepting runoff carrying sediment, the survival rate of plants in the cold season, and the self-sustaining capacity of the ecosystem, realizing the integrated functions of sand interception, drainage, frost resistance, and revegetation.

[0031] The main material of the three-dimensional geocell 16 is a high-density polyethylene (HDPE) or polypropylene (PP) and other high molecular polymers, which are formed into a honeycomb three-dimensional mesh structure by strong welding or riveting.

[0032] It should be noted that vegetation 9 can also be planted in the three-dimensional geocell 16. Usually, some fast-growing, barren-tolerant local pioneer grass species are sown to quickly achieve 100% green coverage of the slope and prevent the topsoil from being washed away by rainwater. In the sinking trough 6, shrubs such as sea buckthorn and caragana, or large herbaceous plants with deep roots such as crested wheatgrass are planted. These plants are relatively fragile in the early stage and have a long growth cycle, but they are the main force for soil stabilization and erosion prevention after they are established. In addition, the space in the sinking trough 6 is limited. After the shrubs such as sea buckthorn have safely passed through the seedling stage and the harsh winter in the ecological trough, their roots must expand rapidly to the outside to obtain water and nutrients in the spring and summer. The nutrient-rich soil layer 8 in the three-dimensional geocell provides a lateral growth bed for them, which can ensure the good growth of vegetation 9 in the sinking trough 6.

[0033] It should be noted that the sinking trough 6 has an inverted cone shape and its height is lower than that of the three-dimensional geocell 16. The three-dimensional geocell 16 naturally forms a dense micro sand-retaining dam to intercept water and soil in a stepped manner. The inverted cone shape has self-stabilizing characteristics, which can effectively concentrate and store fine particles of sediment carried by runoff, promote sediment deposition in the trough and reduce downward transport. At the same time, the cone-shaped sidewalls can guide the water flow to slowly converge and infiltrate, reduce the surface flow velocity, and enhance the sand-retaining efficiency of the slope. The structure of the sinking trough 6 being lower than that of the three-dimensional geocell 16 allows the plant root collar and overwintering buds to be hidden in the wind-sheltered depression, effectively avoiding direct exposure to cold winter winds and frost damage, and significantly improving the overwintering survival rate of plants.

[0034] refer to Figures 1-3 As a preferred approach, the permeable gravel layer 7 has a thickness of 5-10 cm, and the nutrient-rich soil layer 8 has a thickness of 10-15 cm. The thinner permeable gravel layer 7 (5-10 cm) provides efficient bottom drainage and aeration channels, preventing waterlogging during the rainy season and thus reducing plant root rot, while also lowering material costs. The thicker nutrient-rich soil layer 8 (10-15 cm) provides ample growth space, nutrient reserves, and a temperature buffer layer for the roots of vegetation 9, which is conducive to deep root development and enhances the slope's soil stabilization capacity. Especially in the cold season, it provides sufficient coverage and protection for overwintering buds. The reasonable combination of the two layers also ensures the hydraulic connectivity of the perforations, allowing excess water to drain quickly while preventing nutrient loss. This significantly improves the survival rate of vegetation 9 and the ecological restoration effect while ensuring efficient interception of slope runoff and sediment, and also takes into account both economy and ease of construction.

[0035] refer to Figure 2 and Figure 3 As an implementation method, the height of the sinking trough 6 is lower than the height of the nutrient-rich soil layer 8 inside the three-dimensional geocell 16. As a low-lying catchment area, the sinking trough 6 can effectively intercept the sediment and nutrients carried by the slope runoff, promoting deposition and infiltration. The higher soil layer inside the cell guides excess runoff to flow across the cell to the next step in an orderly manner, avoiding concentrated erosion of the vegetation 9 inside the sinking trough 6. Secondly, in the cold season, the low-temperature depression effect of the sinking trough 6 can accumulate snow and fallen leaves, providing a natural insulation layer for overwintering buds. The higher soil layer inside the cell has a stronger heat buffering capacity, which can provide a relatively stable temperature environment for plant roots. The two work together to form a differentiated microhabitat, improving the overall overwintering survival rate of the community. In addition, this structure enhances the roughness of the slope through the difference in soil layer height, significantly weakens the runoff energy, and reduces the amount of earthwork backfilling, taking into account both engineering economy and ecological function synergistic effect.

[0036] It should be noted that the height of the top opening of the sinking trough 6 is 5cm-8cm lower than the surface of the nutrient-rich soil layer 8 inside the three-dimensional geocell 16, thus creating an array of micro depressions on the overall slope.

[0037] refer to Figure 3 As one implementation method, the sinking trough 6 is filled with a heat-insulating substrate 17, which is placed above the nutrient-rich soil layer 8. The heat-insulating substrate 17 is a compound of chopped straw and peat soil. The heat-insulating substrate 17 has a low thermal conductivity and high porosity, which can effectively block the downward conduction of cold in winter, reduce the freezing depth and freezing-thaw frequency of the soil in the sinking trough 6, and create a relatively constant temperature microenvironment for the roots and overwintering buds of the vegetation 9. At the same time, the heat-insulating substrate 17 can absorb and store water and nutrients, and maintain the soil moisture in the trough by slow release, so as to prevent the plants from dying due to drought or freezing. Its filling height is lower than the nutrient-rich soil layer 8 of the grid, which can form a structure of "heat-insulating cover on the top and drainage gravel layer below", which can prevent excessive heat loss and does not affect the infiltration and drainage of excess water during the rainy season.

[0038] refer to Figure 1 As one implementation method, the gabion mattress includes a bottom gabion mattress 12 and an upper gabion mattress 11 positioned above the bottom gabion mattress 12. The bottom gabion mattress 12 and the upper gabion mattress 11 are arranged in a stepped manner, and the surface area of ​​the upper gabion mattress 11 is less than the surface area of ​​the bottom gabion mattress 12. One side of the bottom gabion mattress 12 and the upper gabion mattress 11 abuts against the toe of the slope 10, and the other side of the bottom gabion mattress 12 and the upper gabion mattress 11 extends towards the river channel 15. The stepped arrangement can effectively disperse the horizontal and vertical impact forces of water flow and ice on the slope protection structure. The bottom gabion mattress 12 undertakes the main functions of erosion resistance and foundation protection, while the upper gabion mattress 11 serves as an auxiliary buffer layer. Together, they form a staggered energy dissipation interface, weakening the erosive effect of water flow turbulence on the toe of slope 10; secondly, the part extending towards the river channel 15 can guide the water flow to transition smoothly, avoiding local eddies or waterfall scouring, and expanding the protection range to enhance the protection of the bank slope foundation; at the same time, the side against the toe of slope 10 can prevent water flow from circling or cutting down along the contact surface through close contact, reducing the risk of seepage damage; in addition, the stepped structure facilitates layered filling and compaction during construction, improving overall stability, and the flexibility and permeability of the gabion mattress can adapt to the deformation caused by freeze-thaw and ice impact, preventing brittle structural damage, thus ensuring the anti-icing, anti-erosion, and foundation protection performance while taking into account the convenience of construction and long-term service reliability.

[0039] It should be noted that the bottom gabion mattress 12 and the upper gabion mattress 11 are composed of double-twisted hexagonal wire mesh filled with pebbles and coated with a wear-resistant and corrosion-resistant coating. The double-twisted hexagonal wire mesh has high tensile strength and good flexibility, which can adapt to the local deformation of the slope toe 10 caused by freeze-thaw, ice impact or water erosion without brittle fracture. At the same time, the hexagonal double-twisted structure can effectively prevent the mesh from expanding or falling apart, ensuring the overall stability of the slope protection structure. Secondly, the wear-resistant and corrosion-resistant coating (such as galvanized with PVC or Galfan alloy coating) significantly improves the durability of the wire mesh in humid, freeze-thaw and ice erosion environments, extends its service life and reduces the maintenance frequency. Furthermore, the pebbles used for filling not only provide local materials and reduce costs, but the pores between the pebbles also retain good water permeability and pressure reduction capacity, which can weaken the lifting effect of uplift pressure on the slope toe 10. At the same time, the self-weight and interlocking structure of the pebbles enhance the ability to resist water drag and ice thrust.

[0040] refer to Figure 1 As an implementation method, the willow branch raft 14 is set on the upper surface of the upper gabion mattress 11 and the upper surface of the lower gabion mattress 12. The willow branch raft 14 is also set on the river channel 15 close to the side wall of the lower gabion mattress 12. The willow branch raft arranged on the upper surface of the gabion mattress can directly reduce the turbulence intensity and drag force of the water flow near the wall, and can effectively buffer the impact and erosion of ice or floating objects on the slope toe 10 structure. The part that extends to the river channel 15 close to the side wall of the lower layer guides the flow pattern smoothly in the direction of water flow, inhibits the local scouring and bypass erosion of ice along the edge of the gabion, and significantly enhances the protection range and continuity of the slope toe 10 foundation; secondly, the willow branch raft as A flexible permeable material can generate a micro-resistance effect during flow, reducing the near-bottom flow velocity and promoting the settling of suspended sediment, which helps to form a natural sedimentation layer at the leading edge of the slope toe 10, further reinforcing the slope protection structure. At the same time, living willow branches can sprout roots in suitable seasons, and their root system interweaves between the gabion mattress and the bottom of the river channel 15, forming a reinforced anchoring layer that combines biological and engineering aspects. This not only enhances the overall stability of the gabion mattress, but also improves local water quality and habitat through plant metabolism. In addition, willow branches can be sourced locally, are easy to construct, and are flexible and resistant to water immersion, adapting to freeze-thaw cycles and flow fluctuations, thus meeting multiple needs such as ice resistance, erosion resistance, sedimentation promotion, ecological restoration, and low maintenance costs.

[0041] It should be noted that both the bottom gabion mattress 12 and the upper gabion mattress 11 are connected to the slope toe 10 via anchor bolts 13. Furthermore, the downstream willow branch raft 14 is firmly anchored to the bottom gabion mattress 12, the upper gabion mattress 11, the slope toe 10, and the river channel 15 via U-shaped steel anchors or anchor bolts 13. The anchor bolts 13 tightly connect the gabion mattress to the soil and rock mass of the slope toe 10, effectively resisting the horizontal thrust and buoyancy generated by water flow and ice, preventing the mattress from slipping, overturning, or being lifted by floods. Secondly, the U-shaped steel anchors penetrate the willow branch raft and extend deep into the bed surface of the slope toe 10 and the river channel 15, not only connecting the willow branch raft to the gabion mattress and the slope toe 10... The anchoring of the riverbed forms a unified erosion protection layer, and the penetration anchoring effect restricts the displacement and vibration of the willow branch raft under water flow pulsation or ice impact, protecting the integrity of the willow branch raft and its continuous energy dissipation function. Furthermore, the combined use of anchor rod 13 and U-shaped ground anchor achieves a three-dimensional constraint combining "point-line-surface", enhancing the overall stability and redundancy of the structure under extreme hydraulic conditions. At the same time, the anchoring connection method facilitates rapid on-site construction and positioning, and anchor rod 13 and ground anchor can be made of corrosion-resistant materials, ensuring high reliability in long-term service. It is particularly suitable for ecological slope protection projects at the toe of steep river sections with frequent freeze-thaw cycles, strong ice impact, or steep slopes.

[0042] The "Shunshui Liuzhi Pai 14" is a living shrub paving made from fresh, water-resistant shrub branches such as alpine willow.

[0043] As one implementation method, the height of the willow branch drain 14 near the upstream end of the water flow is higher than the height of the end of the willow branch drain 14 away from the upstream end of the water flow. That is, the surface layer of the willow branch drain is distributed at an acute angle along the water flow direction. The higher willow branch drain at the upstream end can effectively receive and buffer the direct impact of the high-velocity water flow in the main flow area. Through the blocking and lifting effect of the front end of the drain, the kinetic energy of the water flow is actively reduced, and some of the water flow is guided away from the slope toe 10, alleviating the concentrated scouring pressure in the near wall area. Secondly, the height of the willow branch drain gradually decreases along the flow direction, so that the water flow forms a smooth velocity gradient and pressure transition after passing through the willow branch drain, avoiding local backlog or drop. This generates secondary turbulence or erosion, while also facilitating the deposition of carried sediment in the slow-flowing area, gradually forming a natural sediment protection layer at the leading edge of the slope toe 10. Furthermore, this height variation conforms to the law of velocity attenuation along the course of the natural river channel 15 near the bank, adapting to the hydrodynamic distribution under different water levels and flow conditions, and enhancing the structure's robustness to flow fluctuations. In addition, the high upstream and low downstream morphology facilitates the downstream sliding of ice floes or floating objects, reducing accumulation and blockage at the front end of the willow branch raft, and reducing the non-uniform ice thrust borne by the structure. Thus, while ensuring ice resistance, erosion resistance, and sedimentation efficiency, it extends the service life of the downstream willow branch raft 14 and reduces the frequency of maintenance.

[0044] Based on the above structural design, the present invention has the following four significant advantages over the limitations of the prior art: 1. Avoids the risk of damage from freeze-thaw cycles and thawing, resulting in high overall system stability. This invention completely replaces traditional rigid concrete materials. The gabion mattress, the three-dimensional geocell 16, and the water-following willow branch 14 are all flexible structures that can adapt to the frost heave and thaw settlement cycle of the foundation in cold regions and produce coordinated deformation without structural fracture. At the same time, the permeable gravel layer 7 configured at the bottom of the slope surface 5 enables the rapid drainage of excess water, reducing the probability of frost heave disasters from the root of hydrology.

[0045] 2. Construct flexible biomimetic composite armor to effectively resist the erosion and cutting of ice. The designed gabion mattress, combined with the downstream willow branch 14 composite foundation structure, makes full use of the physical elasticity of the living branches and the advantage of downstream layout, which greatly buffers the mechanical collision damage of ice blocks. This design overcomes the engineering weakness of traditional hard revetment slope toe being easily hollowed out by water flow and ice, and significantly improves the durability of bank slope protection.

[0046] 3. Implement multi-stage interception and sand fixation to construct a high-standard sediment control system. By constructing a blind ditch 2 at the top of the slope 1 to intercept and divert water, a three-dimensional geocell 16 on the slope surface 5 to provide tiered blocking, and a nutrient-rich soil layer 8 for infiltration and filtration, a three-dimensional soil and water conservation network is constructed, which guides water, slows flow, intercepts sediment, and filters it. Even in the early stages of the project when vegetation has not yet fully established itself, its physical structure can efficiently intercept sediment flowing down the slope and transform it into a substrate for plant growth on-site, minimizing the amount of sediment entering the river.

[0047] 4. Innovative micro-topography physical intervention significantly improves plant overwintering survival rate. This structure creatively incorporates a sunken trough 6, which improves the plant site conditions at a micro level. This structure creates a natural sheltered and warm microenvironment for seedlings, overcoming the bottleneck problem that conventional ecological slope protection plants in high-altitude and windy areas such as the Qinghai-Tibet Plateau cannot safely overwinter, thus ensuring the long-term greening and restoration of ecological slope protection projects.

[0048] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A stepped sediment control slope protection structure resistant to ice erosion, characterized in that, The structure includes a slope top runoff dispersion and energy dissipation zone, a slope terrace sand-blocking and overwintering zone for planting vegetation (9), and a slope toe ice-erosion resistant flexible base protection zone arranged sequentially from the top of the slope (1) to the bottom of the slope (10). The slope top runoff dispersion and energy dissipation zone includes a blind ditch (2) opened near the top of the slope (1) and parallel to the direction of the river channel (15) and a drop retaining wall (4) set on the side of the blind ditch (2) away from the top of the slope (1). The slope toe ice-erosion resistant flexible base protection zone includes a gabion mattress set on the side of the slope toe (10) away from the top of the slope (1) and a willow branch raft (14) set on the gabion mattress and / or the river channel (15). The willow branch raft (14) extends along the direction of the river channel (15). The slope terrace sand-blocking and vegetation overwintering zone includes multiple three-dimensional geocells (16) arranged in a honeycomb pattern, sinking troughs (6) arrayed in the three-dimensional geocells (16), and vegetation (9) planted in the sinking troughs (6). The sinking troughs (6) are spaced apart by 1 to 3 three-dimensional geocells (16). The bottom of the sinking troughs (6) and the three-dimensional geocells (16) are provided with through holes. The sinking troughs (6) and the three-dimensional geocells (16) are laid with a permeable gravel layer (7) and a nutrient-rich soil layer (8) from bottom to top. The sinking trough (6) has an inverted cone shape, and the height of the sinking trough (6) is lower than the height of the three-dimensional geocell (16). The height of the sinking trough (6) is lower than the height of the nutrient-rich soil layer (8) inside the three-dimensional geocell (16); The thickness of the permeable gravel layer (7) is less than or equal to the thickness of the nutrient-rich soil layer (8).

2. The stepped sediment control slope protection structure against ice erosion according to claim 1, characterized in that, The blind drain (2) is filled with gravel (3), which is wrapped with permeable geotextile.

3. The stepped sediment control slope protection structure against ice erosion according to claim 2, characterized in that, The height of the crushed stone (3) is lower than the height of the top of the slope (1), and the height of the waterfall retaining wall (4) is higher than the height of the crushed stone (3) and the height of the slope terrace sand-blocking and vegetation overwintering zone.

4. The stepped sediment control slope protection structure against ice erosion according to claim 1, characterized in that, The sinking trough (6) is filled with a thermal insulation substrate (17).

5. The stepped sediment control slope protection structure against ice erosion according to claim 1, characterized in that, The gabion mattress includes a bottom gabion mattress (12) and an upper gabion mattress (11) disposed above the bottom gabion mattress (12). The bottom gabion mattress (12) and the upper gabion mattress (11) are arranged in a stepped manner. One side of the bottom gabion mattress (12) and the upper gabion mattress (11) abuts against the toe of the slope (10), and the other side of the bottom gabion mattress (12) and the upper gabion mattress (11) extends toward the river channel (15).

6. The stepped sediment control slope protection structure for resisting ice erosion according to claim 5, characterized in that, The downstream willow branch raft (14) is set on the upper surface of the upper gabion mattress (11) and the upper surface of the bottom gabion mattress (12). The downstream willow branch raft (14) is also set on the river channel (15) in close contact with the side wall of the bottom gabion mattress (12).

7. The stepped sediment control slope protection structure against ice erosion according to claim 1, characterized in that, The height of the willow branch raft (14) near the upstream end of the water flow is higher than the height of the willow branch raft (14) away from the upstream end of the water flow.

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