Ecological bank protection structure suitable for restoration of river bank zone in northwest inland arid region

Abstract

The invention discloses an ecological bank protection structure suitable for restoring a river bank zone of a northwest inland arid region, and particularly relates to the field of ecological bank protection structures, the ecological bank protection structure comprises a bank slope, a water retaining assembly is arranged on one side of the bank slope, the water retaining assembly comprises a PHC pipe pile, a gravel cushion layer and a masonry retaining wall, the PHC pipe pile is inserted into the bottom of one side of the bank slope, and the gravel cushion layer is arranged at the bottom of one side of the bank slope. A plurality of groups of PHC pipe piles are arranged at equal intervals, a gravel cushion layer is laid on the tops of the PHC pipe piles, a grouted rubble retaining wall is arranged on the top of the gravel cushion layer, the outer wall of one side of the grouted rubble retaining wall is connected with a bank slope, gabions are arranged on the side, away from the bank slope, of the water retaining assembly, and a plurality of groups of gabions are arranged at equal intervals. A plurality of groups of anchor rod nets are inserted into the bottom of a bank slope at equal intervals to form an underground anchor rod net structure, soil body slippage caused by river channel scouring is resisted, the gabion gabions are matched with a three-stage protection system of the PHC pipe piles and the grouted rubble retaining walls, the anti-impact capacity is improved, and the ecological function is reserved.

Description

Technical Field

[0001] The present application relates to the field of ecological bank protection structures, and more specifically, to an ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China. Background Art

[0002] The inland northwest region is an arid or semi-arid region with a predominantly dry or semi-arid climate characterized by scarce precipitation, intense evaporation, and large temperature swings between day and night, making it extremely unfavorable for plant growth. Furthermore, the region's soils are often poor, often salinized or sandy, with poor water retention, presenting a severe challenge to plant growth. Under these climatic and environmental conditions, vegetation cover is low, and river banks are susceptible to wind and water erosion, resulting in severe soil and water loss and ecological damage.

[0003] Current traditional river bank slope management technologies either only consider basic functions such as bank soil consolidation and flood control, simply using hardened materials for bank slope management while ignoring ecological management; or stop at the design of shallow bank protection structures while ignoring the improvement of the ecological environment at the fundamental level of the soil, resulting in the bank protection structures not fully realizing their functions; Therefore, in order to solve the above problems, an ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China was proposed. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, the present application provides an ecological bank protection structure suitable for the restoration of river banks in the arid inland areas of Northwest China, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned objectives, the present application provides the following technical solutions: an ecological bank protection structure suitable for the restoration of river banks in the arid areas of the northwest inland area, comprising a bank slope, a water retaining assembly provided on one side of the bank slope, the water retaining assembly comprising PHC pipe piles, a sand and gravel cushion layer and a mortar masonry retaining wall, the PHC pipe piles being inserted into the bottom of one side of the bank slope, the PHC pipe piles being arranged in multiple groups and equidistantly, a sand and gravel cushion layer being laid on the top of the PHC pipe piles, a mortar masonry retaining wall being provided on the top of the sand and gravel cushion layer, an outer wall of one side of the mortar masonry retaining wall being connected to the bank slope, a gabion stone cage being provided on the side of the water retaining assembly away from the bank slope, and the gabion stone cages being arranged in multiple groups equidistantly.

[0006] Preferably, the gabion stone cage includes a wire cage, filling blocks, salt-alkali resistant slow-release capsules and a degradable coconut shell fiber net. The interior of the wire cage is filled with filling blocks, the gaps of the filling blocks are embedded with salt-alkali resistant slow-release capsules, and the edges of the wire cage are embedded with degradable coconut shell fiber nets.

[0007] Preferably, the slope includes a reserved original soil layer, an interlayer of humus, a backfill original soil layer and a surface humus layer. The top of the reserved original soil layer is paved with an interlayer of humus, the top of the interlayer of humus is paved with a backfill original soil layer, the top of the backfill original soil layer is paved with a surface humus, and a degradable jute fiber grid is laid between the reserved original soil layer and the interlayer of humus.

[0008] Preferably, the upper surface of the bank slope is planted with native vegetation, which includes deep-rooted trees, medium-rooted shrubs and shallow-rooted herbaceous plants. The deep-rooted trees and medium-rooted shrubs are planted alternately, and the surface of the surface humus soil is covered with shallow-rooted herbaceous plants.

[0009] Preferably, a diversion groove is provided at the top position between the mortar-made stone retaining wall and the bank slope, and the diversion groove includes a water-facing guide groove, a water-receiving guide groove, a primary energy-cutting peak and an ecological filtration peak. The primary energy-cutting peak is provided on the side of the water-facing guide groove away from the bank slope, the water-receiving guide groove is provided on the side of the primary energy-cutting peak away from the water-facing guide groove, and the ecological filtration peak is provided on the side of the water-receiving guide groove away from the primary energy-cutting peak. The height of the ecological filtration peak is higher than the primary energy-cutting peak, and the depth of the water-receiving guide groove is higher than that of the water-facing guide groove. The bottom water storage surface of the water-facing guide groove is made of porous volcanic rock material, and the surface of the water-facing guide groove is paved with ecological ceramsite.

[0010] Preferably, the surface of the back water guide groove is paved with mycelium fiber felt, the lowest surface of the back water guide groove is provided with water-permeable holes arranged at equal intervals, the bottom of the back water guide groove is provided with a diversion pipe, the water-permeable holes are connected to the diversion pipe, and one side surface of the diversion pipe is connected to a diversion pipe, the diversion pipes are provided in multiple groups and arranged at equal intervals, and the ends of the diversion pipes extend to the top side of the interlayer humus soil.

[0011] Preferably, the material of the wire cage is low carbon steel, the surface of which is galvanized and wrapped with a layer of PVC material. The tensile strength of the wire cage mesh is 400-450 MPa, the mesh wire diameter is 3.2 mm, the mesh size is 75×100 mm, and the particle size of the filling block stone is maintained at 100-300 mm.

[0012] Preferably, the PHC piles are AB type with a standard section length of 200 mm in diameter, and are distributed in 4 rows with a lateral spacing of 0.5 m and a longitudinal spacing of 1.2 m, in multiple rows and columns, with each pile arranged at equal depth.

[0013] Preferably, the stone strength of the mortar-made stone retaining wall is ≥MU30, and the mortar of the mortar-made stone retaining wall is M10 cement mortar with a fluidity of 5 to 7 cm.

[0014] Preferably, the thickness of the surface humus soil is not less than 8 cm, and the thickness of the interlayer humus soil is not less than 35 cm.

[0015] The technical effects and advantages of this application are: 1. Compared with the existing technology, this ecological bank protection structure suitable for the restoration of river banks in the arid inland areas of the northwest is inserted into the bottom of the bank slope at equal intervals by multiple groups to form an underground anchor network structure to resist soil sliding caused by river scouring. The sand and gravel cushion layer is laid on the top of the pipe piles to disperse the load of the mortar masonry retaining wall, relieve frost heave stress, and avoid structural cracking. The mortar masonry retaining wall is closely connected with the bank slope to form a rigid support surface to restrain slope deformation. The synergistic effect of the three forms a "deep anchor-buffer-rigidity" protection chain, which greatly improves the anti-overturning ability and is particularly suitable for the impact of seasonal floods in the northwest. The gabion stone cage is a dynamic protection layer in the water-facing area. Multiple groups are equidistantly arranged on the water-facing side of the water retaining component to directly withstand the impact of water flow. The gabion stone cage is combined with the three-level protection system of PHC pipe piles and mortar masonry retaining wall to improve the anti-scouring ability and retain the ecological function.

[0016] 2. Compared with the existing technology, this ecological bank protection structure suitable for the restoration of river banks in the inland arid areas of the northwest adopts an asymmetric double-peak design through the diversion ditch, dividing the runoff treatment process into two stages: kinetic energy reduction and ecological purification. It perfectly adapts to the characteristics of high intensity and long intervals of rainstorms in the northwest arid areas. The primary energy reduction peak and the ecological filtration peak form a height difference. The depth of the guide ditch on the back water side is greater than that on the front water side. This gradient structure prolongs the water retention time and improves the resource conversion efficiency. The guide ditch on the front water side is located at the front of the ditch and directly receives the runoff from the top of the slope. Its bottom water storage surface is made of porous volcanic rock material, which has a natural honeycomb pore structure and can quickly absorb runoff and slow down the flow rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of this application; Figure 2 This is a schematic diagram of the slope bank structure for this application; Figure 3 This is a schematic diagram of the connection structure between the water retaining assembly and the gabion stone cage of this application; Figure 4 This is a schematic diagram of the cross-sectional structure of the diversion groove of this application; Figure 5 This is a schematic diagram of the gabion stone cage structure of this application; Figure 6 This is a schematic diagram of the three-dimensional structure of the diversion groove of this application; Figure 7 This is a schematic diagram of the connection structure between the guide pipe and the diversion pipe of this application; Figure 8 This is a schematic diagram of the water retaining assembly structure of this application.

[0018] The accompanying drawings are marked as follows: 1. Bank slope; 2. Water retaining assembly; 3. PHC pipe pile; 4. Sand and gravel cushion layer; 5. Mortar stone retaining wall; 6. Gabion stone cage; 7. Wire cage; 8. Filling block stone; 9. Salt-alkali resistant sustained-release capsule; 10. Degradable coconut shell fiber mesh; 11. Reserved original soil layer; 12. Interlayer humus soil; 13. Backfill original soil layer; 14. Surface humus soil; 15. Native vegetation; 16. Deep-rooted trees; 17. Medium-rooted shrubs; 18. Shallow herbaceous plants; 19. Diversion ditch; 20. Water-facing guide ditch; 21. Backwater guide ditch; 22. Primary energy cutting peak; 23. Ecological filtration peak; 24. Ecological ceramsite; 25. Mycelium fiber felt; 26. Water-permeable hole; 27. Diversion pipe; 28. Diversion pipe; 121. Degradable jute fiber grid. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0020] Example 1 As attached Figures 1 to 8 The ecological bank protection structure shown is suitable for the restoration of river banks in the arid areas of the northwest inland area, including a bank slope 1, a water retaining assembly 2 is provided on one side of the bank slope 1, the water retaining assembly 2 includes PHC pipe piles 3, a sand and gravel cushion layer 4 and a mortar masonry retaining wall 5, the PHC pipe piles 3 are inserted into the bottom of one side of the bank slope 1, and the PHC pipe piles 3 are arranged in multiple groups and are arranged at equal intervals. The top of the PHC pipe piles 3 is paved with a sand and gravel cushion layer 4, and the top of the sand and gravel cushion layer 4 is provided with a mortar masonry retaining wall 5, and the outer wall of one side of the mortar masonry retaining wall 5 is connected to the bank slope 1, and the side of the water retaining assembly 2 away from the bank slope 1 is provided with gabion stone cages 6, and the gabion stone cages 6 are provided in multiple groups and are arranged at equal intervals.

[0021] Among them, the soil of the slope 1 is distributed in layers, and PHC pipe piles 3 serve as the anti-pullout foundation. Multiple groups are equidistantly inserted into the bottom of the slope to form an underground anchor network structure to resist soil sliding caused by river scouring. A sand and gravel cushion layer 4 is laid on the top of the pipe piles to disperse the load of the mortar masonry retaining wall 5, relieve frost heave stress, and avoid structural cracking. The mortar masonry retaining wall 5 is closely connected with the slope 1 to form a rigid support surface to constrain slope deformation. The synergistic effect of the three forms a "deep anchor-buffer-rigidity" protection chain, which greatly enhances the anti-overturning ability and is particularly suitable for the impact of seasonal floods in the northwest. Gabion stone cages 6 are dynamic protection layers in the water-facing area. Multiple groups are equidistantly arranged on the water-facing side of the water retaining component 2 to directly withstand the impact of water flow. The gabion stone cages 6, combined with the PHC pipe piles 3 and the mortar masonry retaining wall 5 three-level protection system, have improved anti-scouring capabilities and retained ecological functions.

[0022] Example 2 Based on Example 1, the solution in Example 1 is further detailed in combination with the following specific working methods. Figures 1 to 8 As shown, see the following description for details: As a preferred embodiment, the gabion stone cage 6 includes a wire cage 7, filling blocks 8, salt-alkali resistant slow-release capsules 9 and a degradable coconut shell fiber mesh 10. The interior of the wire cage 7 is filled with filling blocks 8, and the gaps of the filling blocks 8 are embedded with salt-alkali resistant slow-release capsules 9. The edges of the wire cage 7 are embedded with degradable coconut shell fiber mesh 10. The filling blocks 8 are densely graded to reduce the kinetic energy of water. The salt-alkali resistant slow-release capsules 9 are salt-alkali resistant slow-release bags. Under the action of moisture and microorganisms, they slowly release improved substances and nutrients to neutralize salt and alkali. The degradable coconut shell fiber mesh 10 guides plant roots to penetrate the gaps in the stone cage to form biological anchors. Through the triple linkage of physical energy dissipation, chemical improvement and biological soil consolidation, the anti-impact flow rate is increased to 3.2 m / s.

[0023] As a preferred embodiment, the bank slope 1 includes a reserved original soil layer 11, an interlayer humus 12, a backfill original soil layer 13 and a surface humus 14. The top of the reserved original soil layer 11 is paved with an interlayer humus 12, the top of the interlayer humus 12 is paved with a backfill original soil layer 13, and the top of the backfill original soil layer 13 is paved with a surface humus 14. A degradable jute fiber grid 121 is laid between the reserved original soil layer 11 and the interlayer humus 12. Layer 11 retains foundation stability, the interlayer humus 12 provides a nutrient reservoir for trees, the backfill original soil layer 13 transfers moisture, improves water retention, and improves vegetation survival rate. The surface humus 14 provides for herb growth, and the degradable jute fiber grid 121 is set at the bottom of the interlayer humus 12 to intercept nutrient infiltration and guide the deep roots of trees and the middle roots of shrubs to interweave into a mesh-like soil-solidifying structure. At the same time, it can reduce the loss of the interlayer humus 12 and improve the survival rate of deep-rooted trees 16.

[0024] As a preferred embodiment, the upper surface of the bank slope 1 is planted with native vegetation 15, which includes deep-rooted trees 16, medium-rooted shrubs 17 and shallow-layer herbaceous plants 18. The deep-rooted trees 16 and the medium-rooted shrubs 17 are planted alternately, and the surface of the surface humus 14 is covered with shallow-layer herbaceous plants 18. The deep-rooted trees 16 play the role of anchoring the foundation, and the main roots are vertically penetrated to a depth of more than 1.5m, penetrating the degradable jute fiber grid 121 and anchored to the reserved original soil layer 11. The root network enhances the anti-slip capacity of the bank slope 1, transpiration lowers the groundwater level, and inhibits the upwelling of salt and alkali. Medium-rooted shrubs 17 and deep-rooted trees 16 are planted alternately, with the lateral roots extending horizontally to a radius of >1.2m, interwoven with the tree roots to form a network structure, intercepting slope runoff. Dead branches and leaves replenish soil organic matter, and dense branches reduce wind erosion intensity. Shallow herbaceous plants 18 have densely distributed fibrous roots in the 0-20cm soil layer, forming an anti-scour blanket structure, covering the surface to reduce splash erosion and increase rainwater infiltration rate.

[0025] As a preferred embodiment, a diversion groove 19 is provided at the top position between the mortar-made stone retaining wall 5 and the bank slope 1. The diversion groove 19 includes a water-facing guide groove 20, a water-receiving guide groove 21, a primary energy-removing peak 22 and an ecological filtration peak 23. The water-facing guide groove 20 is provided with a primary energy-removing peak 22 on the side away from the bank slope 1, the primary energy-removing peak 22 is provided with a water-receiving guide groove 21 on the side away from the water-facing guide groove 20, and the water-receiving guide groove 21 is provided with an ecological filtration peak 23 on the side away from the primary energy-removing peak 22. The height of the ecological filtration peak 23 is higher than The primary energy reduction peak 22 is formed, and the depth of the back-water guide groove 21 is higher than that of the front-water guide groove 20. The bottom water storage surface of the front-water guide groove 20 is made of porous volcanic rock, and the surface of the front-water guide groove 20 is paved with ecological ceramsite 24. Among them, the diversion groove 19 is located at the top position between the mortar-made stone retaining wall 5 and the bank slope 1. According to the special hydrological conditions of the inland arid area of ​​the northwest, the intelligent regulation, resource utilization and ecological restoration of runoff are achieved through the layered structure. The diversion groove 19 adopts an asymmetric double-peak design, which divides the runoff treatment process into kinetic energy reduction and resource utilization. The two stages of ecological purification are perfectly adapted to the characteristics of heavy rain and long intervals in the arid northwest region. The primary energy reduction peak 22 and the ecological filtration peak 23 form a height difference. The depth of the backwater guide groove 21 is greater than that of the frontwater guide groove 20. This gradient structure prolongs the water retention time and improves the resource conversion efficiency. The frontwater guide groove 20 is located at the front of the groove and directly receives the top runoff. The bottom water storage surface is made of porous volcanic rock, which has a natural honeycomb pore structure and can quickly absorb runoff and slow down the flow rate. At the same time, the ecological ceramsite 2 laid on its surface 4 further enhances the coarse filtration function and intercepts suspended particles with a particle size greater than 5mm. At the same time, the ecological ceramsite 24 has the function of slowly discharging water after absorbing water, so that the water collected by the water-facing guide channel 20 slowly flows into the bank slope 1. The primary energy-cutting peak 22 is set on the side of the water-facing guide channel 20 away from the bank slope 1. Through the shallow bulge, the hydraulic jump phenomenon is induced to reduce the initial flow rate from 2.5m / s to 0.8m / s, reducing the energy by 40%. The primary energy-cutting peak 22 intercepts the surface humus 14 flowing downward under the scouring of heavy rain to prevent soil and water loss.

[0026] As a preferred embodiment, the surface of the back water surface guide groove 21 is paved with mycelium fiber felt 25, the lowest surface of the back water surface guide groove 21 is equidistantly arranged with water permeable holes 26, the bottom of the back water surface guide groove 21 is provided with a diversion pipe 27, the water permeable holes 26 are connected to the diversion pipe 27, and one side surface of the diversion pipe 27 is connected with a diversion pipe 28. The diversion pipes 28 are provided in multiple groups and are equidistantly arranged. The end of the diversion pipe 28 extends to the top side of the interlayer humus soil 12, wherein the ecological filtration peak 23 is provided on the side of the back water surface guide groove 21 away from the primary energy cutting peak 22, and its higher protruding structure forms a physical barrier, which can play a certain blocking role when the water level rises to avoid direct entry into the bank slope 1, and the mycelium fiber felt 25 laid on the surface is embedded with jute fiber mesh and nitrogen-fixing bacteria. The colloid composition activates the microbial reaction when the runoff passes through. The nitrogen-fixing bacteria release ammonium nitrogen and the phosphate-dissolving bacteria dissociate phosphate, which directly increases the content of fast-acting nutrients in the water. During the drought period in the arid area, the mycelium fiber felt 25 automatically goes dormant to achieve zero-energy maintenance, and cooperates with the recharge function of the PHC pipe pile 3 to replenish groundwater. The permeable holes 26 serve as clean water collection nodes and are directly connected to the diversion pipe 27 at the bottom. The equidistant layout of the permeable holes 26 ensures uniform distribution of water flow and avoids local siltation. The diversion pipe 27 serves as the main transmission channel and is made of high-density polyethylene. It guides the filtered runoff to the diversion pipe 28, and targeted irrigation is achieved by guiding the diversion pipe 28. At the same time, the active substances of the mycelium fiber felt 25 are transported with the water flow, thereby improving the organic matter conversion rate of the interlayer humus soil 12 by 40%.

[0027] As a preferred embodiment, the material of the wire cage 7 is low-carbon steel, the surface of which is galvanized and wrapped with a layer of PVC material. The tensile strength of the mesh of the wire cage 7 is 400-450Mpa, the mesh diameter is 3.2mm, the mesh size is 75×100mm, and the particle size of the filling block 8 is maintained at 100-300mm. Among them, the PVC layer is wrapped with galvanized low-carbon steel wire, with a tensile strength of 400-450MPa, a mesh of 75×100mm, and a mesh diameter of 3.2mm, forming a high-strength flexible frame to constrain the displacement of the filling block 8 and resist the shear force of water flow. The PVC coating resists salt and alkali corrosion and has a service life of more than 25 years. The mesh structure provides a penetration channel for vegetation roots.

[0028] As a preferred embodiment, the PHC pipe piles 3 adopt AB type and standard section length with a diameter of 200 mm, and the PHC pipe piles 3 are distributed in 4 rows horizontally, with a horizontal spacing of 0.5 m and a longitudinal spacing of 1.2 m, and are distributed in multiple rows and columns. Each pile is arranged at an equal depth. Among them, the PHC pipe piles 3 have high-strength prestressed characteristics, are arranged in 4 rows horizontally, with a horizontal spacing of 0.5 m and a longitudinal spacing of 1.2 m, forming a dense shear net structure, unifying the pile sinking depth, and ensuring uniform force at the bottom of the slope 1.

[0029] As a preferred embodiment, the stone strength of the mortar masonry retaining wall 5 is ≥MU30, and the mortar of the mortar masonry retaining wall 5 is M10 cement mortar with a fluidity of 5 to 7 cm, wherein MU30 stone improves resistance to flood impact, and 5 to 7 cm fluidity mortar ensures full mortar joints.

[0030] As a preferred embodiment, the thickness of the surface humus 14 is not less than 8 cm, and the thickness of the interlayer humus 12 is not less than 35 cm. The interlayer humus 12 provides rooting space for deep-rooted trees 16, and the anchoring force of the main root is enhanced. The 35 cm thickness ensures the organic matter reserves and meets the annual fertilizer requirements of the trees. The surface humus 14 can cover the roots of shallow herbaceous plants 18.

[0031] The working process of this application is as follows: First, use the phased cofferdam to build the design area into a construction range that is convenient for construction, determine the layout position of the gabion stone cage 6, the piling surface of the PHC pipe pile 3 and the layout height of the mortar stone retaining wall 5, and use construction machinery to carry out earth excavation, mainly excavating the earth on the bank slope 1 and the leveling groove for placing the gabion stone cage 6, forming the leveling groove for the gabion stone cage 6 and the piling range of the PHC pipe pile 3. The earth on the bank slope 1 should be excavated to the reserved original soil layer 11 for subsequent soil paving. The wire cage 7 of the gabion stone cage 6 is made of low-carbon steel, and its surface is galvanized and then wrapped with a layer of PVC (polyvinyl chloride) material for anti-rust and anti-corrosion treatment. , the tensile strength of the wire cage 7 mesh is 400-450Mpa, the mesh diameter is 3.2mm, the mesh size is suitable for completely wrapping the large stone 8, and the size is 75×100mm. The large stone is filled in the woven wire cage 7. The stone particle size should be kept between 100 and 300mm, and the stone texture is hard and not easy to weather. Thin sheets or long strips of stone should not be used to avoid damage to the structure of the wire cage 7. During the filling process, the filling stones 8 should be closely arranged and fully compacted to reduce the deformation of the wire cage 7 and avoid gaps. After the filling is completed, the wire mesh at the edge of the wire cage 7 is tightened with special tools to ensure the firmness of the overall structure; AB type, standard section length PHC pipe piles 3 with a diameter of 200mm are used, and mechanical pile sinking is carried out using a vibrating pile driver. They are distributed in 4 rows horizontally with a horizontal spacing of 0.5m and a vertical spacing of 1.2m, that is, they are distributed in multiple rows and columns to ensure that each pile is arranged at equal depth. A small and medium-sized sand and gravel cushion layer 4 is used on the upper part of the solid soil foundation of the PHC pipe piles 3 for laying, compacting and leveling. As the foundation of the embankment, on the one hand, it protects the solid soil foundation below from scouring, and on the other hand, it carries the load of the upper mortar masonry retaining wall 5, so that it can effectively support the soil in the bank slope 1. The mortar masonry retaining wall 5 is built strictly in accordance with the construction process. After the mortar masonry retaining wall 5 structure hardens, the soil backfilling work of the riverbank vegetation planting zone is carried out. A layer of interlayer humus soil 12, that is, a humus soil layer, is directly laid on the reserved original soil layer 11, the thickness of which is not less than 35cm. After compaction, the backfill original soil layer 1 is laid on the interlayer humus soil 12 3. At this time, the overall shape of the bank slope 1 should be made into a stepped shape, and the bottom surface of the stepped shape should be slightly lower than the top of the mortar masonry retaining wall 5 so that the surface humus 14 can be laid. The thickness of the surface humus 14 should be no less than 8 cm. The combination of the interlayer humus 12 and the backfill original soil layer 13 can effectively improve the soil aggregate structure and enhance its water retention capacity. After the backfill work of the bank slope 1 is completed, the planting of suitable plants in the plant planting belt is carried out. By planting native vegetation 15 in layers, including deep-rooted trees 16, medium-rooted shrubs 17 and shallow-layer herbaceous plants 18, the vertical stratification characteristics of their root systems are utilized to achieve the purpose of deep root anchoring the soil layer and shallow root intercepting surface runoff, thereby forming a multi-level ecological barrier. When the vegetation canopy coverage reaches a certain level, the shade of the trees can effectively reduce the evaporation of the bank slope 1. At the same time, the fallen leaves of the vegetation can continuously supplement the soil nitrogen, phosphorus, potassium and other elements, so that the quick-acting nutrients in the surface soil increase year by year.

Claims

1. An ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China, comprising a bank slope (1), characterized in that: A water retaining assembly (2) is provided on one side of the bank slope (1), and the water retaining assembly (2) comprises a PHC pipe pile (3), a gravel cushion layer (4), and a mortar masonry retaining wall (5). The PHC pipe pile (3) is inserted into the bottom of one side of the bank slope (1). The PHC pipe pile (3) is provided in multiple groups and arranged at equal intervals. A gravel cushion layer (4) is laid on the top of the PHC pipe pile (3). A mortar masonry retaining wall (5) is provided on the top of the gravel cushion layer (4). The mortar masonry retaining wall (5) is provided on the top of the gravel cushion layer (4). One side outer wall of the wall (5) is connected to the bank slope (1); a gabion stone cage (6) is provided on the side of the water retaining assembly (2) away from the bank slope (1); and the gabion stone cage (6) is provided with a plurality of groups arranged at equal intervals; a diversion groove (19) is provided at the top position between the mortar-laid stone retaining wall (5) and the bank slope (1); and the diversion groove (19) includes a water-facing surface guide groove (20), a water-receiving surface guide groove (21), a primary energy-reducing peak (22), and an ecological filtration peak (23).

2. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 1 is characterized by: The gabion stone cage (6) comprises a wire cage (7), filling blocks (8), salt-alkali resistant slow-release capsules (9) and a degradable coconut shell fiber net (10), wherein the interior of the wire cage (7) is filled with the filling blocks (8), the salt-alkali resistant slow-release capsules (9) are embedded in the gaps of the filling blocks (8), and the degradable coconut shell fiber net (10) is embedded in the edges of the wire cage (7).

3. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 1 is characterized by: The bank slope (1) comprises a reserved original soil layer (11), an interlayer humus soil (12), a backfilled original soil layer (13) and a surface humus soil (14); the top of the reserved original soil layer (11) is paved with an interlayer humus soil (12); the top of the interlayer humus soil (12) is paved with a backfilled original soil layer (13); the top of the backfilled original soil layer (13) is paved with a surface humus soil (14); and a degradable jute fiber grid (121) is paved between the reserved original soil layer (11) and the interlayer humus soil (12).

4. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 3 is characterized by: The upper surface of the bank slope (1) is planted with native vegetation (15), and the native vegetation (15) includes deep-rooted trees (16), medium-rooted shrubs (17) and shallow-layer herbaceous plants (18). The deep-rooted trees (16) and the medium-rooted shrubs (17) are planted in an alternating manner, and the surface of the surface humus soil (14) is covered with shallow-layer herbaceous plants (18).

5. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 4 is characterized by: A primary energy-cutting peak (22) is provided on the side of the water-facing surface guide groove (20) away from the bank slope (1); a back-facing surface guide groove (21) is provided on the side of the primary energy-cutting peak (22) away from the water-facing surface guide groove (20); an ecological filtration peak (23) is provided on the side of the back-facing surface guide groove (21) away from the primary energy-cutting peak (22); the height of the ecological filtration peak (23) is higher than the primary energy-cutting peak (22), and the depth of the back-facing surface guide groove (21) is higher than that of the water-facing surface guide groove (20); the bottom water storage surface of the water-facing surface guide groove (20) is made of porous volcanic rock material, and the surface of the water-facing surface guide groove (20) is paved with ecological ceramsite (24).

6. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 5 is characterized by: The surface of the backwater guide groove (21) is paved with a mycelium fiber felt (25), the lowest surface of the backwater guide groove (21) is provided with water-permeable holes (26) arranged at equal intervals, the bottom of the backwater guide groove (21) is provided with a diversion pipe (27), the water-permeable holes (26) are connected to the diversion pipe (27), and one side surface of the diversion pipe (27) is connected to a diversion pipe (28), the diversion pipe (28) is provided in multiple groups and arranged at equal intervals, and the end of the diversion pipe (28) extends to the top side of the interlayer humus soil (12).

7. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 2 is characterized by: The material of the steel wire cage (7) is low carbon steel, the surface of which is galvanized and wrapped with a layer of PVC material. The tensile strength of the mesh of the steel wire cage (7) is 400-450 MPa, the diameter of the mesh wire is 3.2 mm, the mesh size is 75×100 mm, and the particle size of the filling block stone (8) is maintained at 100-300 mm.

8. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 7 is characterized by: The PHC pipe piles (3) are AB-shaped and have a standard section length of 200 mm in diameter. The PHC pipe piles (3) are distributed in four horizontal rows with a horizontal spacing of 0.5 m and a vertical spacing of 1.2 m, forming a multi-row and multi-column distribution, and each pile is arranged at an equal depth.

9. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 5 is characterized by: The stone material strength of the mortar masonry retaining wall (5) is ≥MU30, and the mortar of the mortar masonry retaining wall (5) is M10 cement mortar with a fluidity of 5 to 7 cm.

10. The ecological bank protection structure suitable for river bank restoration in the arid inland areas of Northwest China according to claim 6 is characterized by: The thickness of the surface humus soil (14) is not less than 8 cm, and the thickness of the interlayer humus soil (12) is not less than 35 cm.

Images