CN113944138A

CN113944138A - Construction method of natural bank slope protection structure based on sponge city concept

Info

Publication number: CN113944138A
Application number: CN202010679989.9A
Authority: CN
Inventors: 吴国清; 李环辉; 柯锦文; 黄小玲; 庄锦河
Original assignee: Xiamen Zhongyin Construction Engineering Co ltd
Current assignee: Xiamen Zhongyin Construction Engineering Co ltd
Priority date: 2020-07-15
Filing date: 2020-07-15
Publication date: 2022-01-18
Anticipated expiration: 2040-07-15
Also published as: CN113944138B

Abstract

The invention relates to a construction method of a natural bank slope protection structure based on a sponge city concept, which comprises the following steps: s1, construction of a filter pond: excavating a filter pond foundation groove, forming a water filtering gabion A and a water filtering gabion B, paving a permeable geotextile, filling a regulation and storage layer, pre-burying a drainage blind pipe B and filling planting soil B; s2, constructing a prefabricated rain channel and a prefabricated water permeable step; s3, terrace type bank protection construction: laying permeable geotextile, layering and spreading bank slope broken stone and rolling operation, driving a living wood pile, constructing backfill and planting a fiber blanket; s4, constructing a hydrophilic footpath; s5, constructing a grass planting drainage ditch: the method comprises the steps of excavating a groove of a grass planting drainage ditch, building a prefabricated catchment ridge and a prefabricated overflow ridge, laying permeable geotextile, constructing broken stones of the drainage ditch, burying a drainage blind pipe A and filling planting soil A. The bank slope protection structure is convenient to construct and stable in structure, and realizes 'natural accumulation, natural permeation and natural purification'.

Description

Construction method of natural bank slope protection structure based on sponge city concept

Technical Field

The invention belongs to the field of hydraulic engineering, and particularly relates to natural bank slope protection based on a sponge city idea, which is suitable for river bank slope protection construction and river bank slope protection construction with higher landscape requirements.

Background

With the high-speed development of cities, the damage of agriculture, industry and human activities to a river ecological system is increasingly serious, and a large amount of agricultural non-point source pollution, industrial wastewater, domestic sewage and the like are directly discharged into a river, so that the water quality is deteriorated, and the ecological environment of the river is seriously polluted. Stereoplasm revetment such as reinforced concrete, grout stone of building block that adopts in traditional river course renovation, for example the patent number is CN207244563U discloses an ecological stereoplasm revetment structure, including upright bank section and connect the slope bank section in upright bank section top, be provided with a plurality of parting beads on the slope bank section, the junction that the parting bead is located slope bank section and upright bank section is connected with the porous concrete link plate, set up the plug-in hole that supplies the filled groove that nutrient soil and zeolite molecular sieve filled and communicate with the filled groove on the porous concrete link plate, it has the root to arrange the lian plant in the filled groove in to peg graft in the plug-in hole.

Above-mentioned stereoplasm bank protection has obstructed land and water material and energy exchange, has destroyed biological diversity, has weakened the ecological nature restoration function in river course, and the stereoplasm bank protection can't self-absorption discharge into the pollution load in river course, can not effectively maintain or improve quality of water. In addition, in the treatment process of some river channels, due to the change of the covering conditions of the slope, the infiltration pressure of underground water, the slope gradient, the geometric characteristics and the like, the phenomena of ditch digging and collapse are more serious. Therefore, the ecological priority principle of 'natural accumulation, natural infiltration and natural purification' of the sponge city is implemented, and the construction of natural bank slope protection becomes an important development direction for river channel management and urban ecological construction.

Disclosure of Invention

The invention aims to provide a construction method of a natural bank slope protection structure based on a sponge city concept, aiming at the problems of water and land energy and material exchange obstruction, incompleteness of a water ecosystem, low self-purification capability, easiness in ditch opening and collapse and the like of the traditional hard slope protection.

In order to achieve the technical purpose, the invention adopts the following technical scheme:

the invention relates to a construction method of a natural bank slope protection structure based on a sponge city concept, which comprises the following steps:

s1, construction of a filter pond: excavating a filtering pond foundation groove at the foot part of a river bank and tamping the filtering pond foundation groove, respectively installing gabions at two sides of the filtering pond foundation groove, uniformly and hierarchically filling the gabions to form a water filtering gabion A and a water filtering gabion B, burying embedded pipes in the fillers in the process of filling the water filtering gabion A, laying permeable geotextile between the water filtering gabion A and the water filtering gabion B, hierarchically filling a regulation layer and embedding drainage blind pipes B therein, laying a filter layer on the regulation layer and filling planting soil B;

s2, construction of a prefabricated rain-drenching ditch and a prefabricated water-permeable step: excavating a rain-drop ditch foundation groove according to the position of the embedded pipe, leveling and compacting, laying a sand cushion layer on the upper part of the foundation groove, building the prefabricated rain-drop ditches section by section according to the sequence from bottom to top, and laying prefabricated water-permeable steps on the upper parts of the prefabricated rain-drop ditches according to the sequence from bottom to top;

s3, terrace type bank protection construction: paving permeable geotextiles on two sides of the prefabricated permeable step, performing bank slope broken stone layered paving and rolling operation on the permeable geotextiles, driving at least two rows of living timber piles on the bank slope broken stones, reserving a gap between the bottom row of living timber piles and the water filtering gabion A, and sequentially constructing backfill and planting fiber blankets on the bank slope broken stones;

s4, hydrophilic pavement construction: paving a prefabricated water-permeable footpath plate at a gap between the bottom row living timber pile and the water-filtering gabion A to form a hydrophilic footpath;

s5, constructing a grass planting drainage ditch: digging a grass planting drainage ditch groove, clinging to one side of the grass planting drainage ditch groove, clinging to a prefabricated deluge ditch to build a prefabricated catchment bank, clinging to one side of the grass planting drainage ditch groove, clinging to a terrace type revetment to build a prefabricated overflow bank, wherein the prefabricated overflow bank is provided with an overflow port at a position higher than the terrace type revetment, the prefabricated catchment bank is provided with a water gathering port communicated with the prefabricated deluge ditch, the water gathering port is provided with a filter screen at one side of the prefabricated deluge ditch away from the prefabricated deluge ditch, then laying permeable geotextile on the bottom and the inner wall of the grass planting drainage ditch groove, constructing drainage ditch broken stones on the upper part of the permeable geotextile and burying a drainage blind pipe A underground, and filling planting soil A on the upper part of the drainage broken stones.

Preferably, when the gabions are filled in the step S1, the layering thickness is controlled to be 30cm +/-2 cm, and the gabions are covered after the top fillers are paved and leveled, so that the water-filtering gabions A and the water-filtering gabions B are formed.

Preferably, in the step S1, in the process of filtering the water of the gabion a, the position of the water outlet of the prefabricated rain ditch is measured and placed on the side surface of the gabion, the embedded pipe is embedded according to the measured position of the water outlet of the prefabricated rain ditch, and the filler near the embedded pipe is lightly compacted by a hand hammer.

Preferably, in the step S1, when the permeable geotextile is laid between the water filtering gabion a and the water filtering gabion B, the permeable geotextile is reversely wrapped to the elevation position of the planting soil B and fixed; when the storage layer is laid, the thickness of each layer is controlled to be 15-20 cm, and the thickness of each layer is manually arranged by a shovel; the thickness of the filter layer is controlled to be 50-100 mm; the depth of the planting soil B is controlled to be 400-600 mm, and the layered filling thickness is controlled to be within 300 mm.

Preferably, the two sides and the top of the prefabricated rain-sprinkling ditch are provided with grooves and tongues; in the step S2, the prefabricated deluge ditch is laid flatly, so that the prefabricated deluge ditch on the upper layer is joggled with the prefabricated deluge ditch on the lower layer through the rabbet, and is beaten stably by a rubber hammer; and after the prefabricated rain-sprinkling trench is maintained for 7d, the prefabricated water-permeable step is embedded and fixed in a rabbet at the top of the prefabricated rain-sprinkling trench.

Preferably, in step S3, the permeable geotextile is laid from the top of the slope to the bottom of the slope by a manual rolling and laying method; the layered paving thickness of the bank slope crushed stone is controlled within 200mm, the compactness is not less than 95%, and the manual paving and rolling are adopted for the bank slope crushed stone near the rain-drenching ditch.

Preferably, when the living timber pile is driven in step S3, each pile driving position is measured and placed on the shore slope crushed stone, then the excavator is put in place, after the living timber pile is straightened, the bucket of the excavator is turned over to press the living timber pile into the shore slope crushed stone, after the pile is pressed stably, the back of the bucket is used for striking the pile head of the living timber pile, and the living timber pile is vertically driven into the shore slope crushed stone to the designed depth.

Preferably, in the step S3, the backfill construction adopts a mechanical-manual mode to pave and tamp in layers, the thickness of each layer should not exceed 25 cm-30 cm, each layer is tamped for 3-4 times, the degree of compaction should be greater than or equal to 95%, and the backfill construction should be finished according to the designed gradient when backfilling to the top layer;

when the plant fiber blanket is constructed, the plant fiber blanket is laid in the direction from the top of a slope to the toe of the slope, the plant fiber blanket is smoothly and tightly spread, the lap joint width between the plant fiber blankets is not less than 10cm, the top, the bottom and the lap joint part of the plant fiber blanket are firmly fixed by using anchor bolts, a folding cover part is reserved, the number of the anchor bolts is not less than 3 per 1m2, and then the reserved plant fiber blanket is folded and covered on the side surface of backfill soil and fixed by using the anchor bolts.

Preferably, when the hydrophilic pavement is constructed in the step S4, a sand leveling layer is paved on the upper portion of the shore slope gravels layer by layer and water is sprayed to compact, then prefabricated water-permeable pavement plates are paved on the sand leveling layer block by block, the joints between the water-permeable pavement plates are filled with sand, and the joints are rolled for 2-3 times by a small vibration rolling machine after the sand filling is completed.

Preferably, in the step S5, the two sides of the prefabricated weirs are provided with grooves and tongues, the two sides and the top of the prefabricated catchment ridges are provided with grooves and tongues, when the weirs and the prefabricated catchment ridges are prefabricated, the adjacent prefabricated weirs are engaged with the grooves and tongues on the two sides of the prefabricated weirs, the prefabricated catchment ridges are engaged with the grooves and tongues on the two sides of the adjacent prefabricated weirs through the grooves and tongues on the two sides, when the prefabricated weirs and the prefabricated catchment ridges are built, the mounting position lines of the prefabricated weirs and the prefabricated catchment ridges are measured and placed on the side of the grass planting drainage ditch close to water, cement mortar is mixed to be paved, the thickness of the mortar is 30mm, the prefabricated weirs and the prefabricated catchment ridges are built section by section according to the line placing positions, cement mortar jointing is timely adopted after the building is completed, and wet-process curing is performed; the filling thickness of the planting soil A is 10-20 cm, a prefabricated water permeable pedal connected with the prefabricated water permeable step is laid above the planting soil A after the filling of the planting soil A is completed, and the prefabricated water permeable pedal is embedded and fixed at an opening at the top of the prefabricated catchment ridge.

Compared with the prior art, the invention has the following characteristics and beneficial effects:

(1) the invention forms multi-stage natural bank slope protection of 'grass planting drainage ditch + terrace type revetment + hydrophilic footpath + filter pond', on one hand, part of rainwater on the top and the slope surface is left, and a 'sponge dike' which is naturally stored, naturally permeated and naturally purified is built, thereby realizing the continuity from the riverway waterfront area to the land area ecological system and providing a hydrophilic space for users; on the other hand, the pressure of urban drainage is reduced, and underground water is supplemented.

(2) The grass planting drainage ditch is arranged at the top of the dike, and has the functions of water purification, water storage, drainage and water supply, so that the vegetation maintenance cost is reduced, and the consumed cost is low. In rainy days, the gravel layer with good water permeability can permeate redundant rainwater to the underground to achieve the effect of water storage, and the redundant rainwater can be discharged to a bank slope through the overflow port; when rainstorm comes, rainwater can be discharged in time through the drainage blind pipe and the rain-sprinkling ditch, and water purification and water delivery are facilitated.

(3) The invention arranges a terrace type bank protection at the bank slope part, and gravels filled at the bottom of the bank protection can store and purify part of rainwater; a plurality of rows of living timber piles are arranged in the broken stones and backfilled soil is filled, so that the side slope is effectively slowed down and the soil body loss is prevented; plant fiber blanket is laid on rubble upper portion and the anchor nail is inserted, on the one hand the water-retaining characteristic of full play natural plant fiber, contains and stays 20% -25% rainwater or irrigation water, and on the other hand realizes the muscle bank protection effect through the outer shaping net of plant fiber blanket, has improved the stability of bank protection.

(4) The rain channels are longitudinally arranged on the bank slope part and are formed by splicing the prefabricated sections of the rain channels, so that the construction is convenient and fast, and the economy is good; meanwhile, the method can remove the road surface passenger water, reduce the influence of the road surface passenger water on the embankment top on the bank slope, ensure the safety of the slope protection, and prevent the slope surface from being ditched or collapsed; the prefabricated permeable step is installed at the top of the prefabricated rain-drop ditch, so that rainwater of partial bank slope runoff can permeate into the prefabricated rain-drop ditch, and a 'hydrophilic channel' is provided for a user.

(5) According to the invention, the filtering pond is arranged at the toe part of the slope, and the hygrophyte combined plants are planted in the filtering pond, so that rainwater can be collected and purified, and rainwater collection, infiltration and recycling are realized; on the other hand, the landscape effect of more water storage and more green without water is realized. The water filtering gabions are arranged on two sides of the filtering pond, and stones are filled in the gabions, so that water quality exchange between rivers and revetments is facilitated; meanwhile, a biological membrane can be hung, so that a certain purification effect is achieved; in addition, the porous structure of the gabion can provide a habitat channel, and is beneficial to the reproduction of small aquatic organisms.

Drawings

FIG. 1 is a schematic drawing of excavation and tamping of a foundation trench of a filter pond;

FIG. 2 is a schematic view of a filtration gabion installation;

FIG. 3 is a schematic illustration of filter pond backfill;

FIG. 4 is a schematic view of a deluge construction;

FIG. 5 is a perspective view of a prefabricated rainchannel;

FIG. 6 is a perspective view of a prefabricated water permeable step;

FIG. 7 is a schematic diagram of a shore slope gravel pack;

FIG. 8 is a schematic view of the driving of a live stump;

FIG. 9 is a schematic diagram of land slope backfill filling;

FIG. 10 is a schematic view of the plant fiber blanket laying anchoring;

FIG. 11 is a schematic view of a hydrophilic walkway construction;

FIG. 12 is a schematic view of a grass planting gutter groove excavation;

fig. 13 is a schematic diagram of the construction of the prefabricated weirs and the prefabricated catchment sills;

fig. 14 is a perspective view of a prefabricated weir;

fig. 15 is a perspective view of a prefabricated catchment sill;

FIG. 16 is a schematic diagram of grass planting gutter backfill;

FIG. 17 is a natural bank slope protection plan based on the sponge city concept;

FIG. 18 is a schematic diagram of a natural bank slope protection structure based on the sponge city concept;

FIG. 19 is a section A-A of natural bank slope protection based on the concept of sponge city;

fig. 20 is a B-B sectional view of natural bank slope protection based on the concept of sponge city.

In the figure: 1. the method comprises the following steps of planting grass and a drainage ditch, 101 planting soil A, 102 drainage ditch broken stones, 103 drainage blind pipes A, 2 terrace type revetment, 201 planting fiber blankets, 202 anchoring bolts, 203 living wood piles, 204 backfilling soil, 205 bank slope broken stones, 3 hydrophilic footpath, 301 prefabricated permeable footpath plates, 4 filtering ponds, 401 detention ponds, 402 planting soil B, 403 filtering layers, 404 regulating and storing layers, 405 drainage blind pipes B, 5 prefabricated overflow ridges, 501 overflow ports, 6 prefabricated water collection ridges, 601 water collection ports, 602 filtering nets, 7 prefabricated rain gutters, 8 prefabricated permeable steps, 9 prefabricated permeable pedals, 10 drainage gabion A, 1001 pre-buried pipes, 11 gabion B, 12 permeable geotextiles and 13 river water.

Detailed Description

The present invention will be described in further detail below by way of examples with reference to the accompanying drawings, and the following examples are illustrative of the present invention and are not limited to the following examples. A river bank slope protection project adopts natural bank slope protection based on a sponge city idea.

s1, construction of a filter pond 4: referring to fig. 1, a filtering pond foundation trench is excavated at the bottom of a river bank and tamped;

referring to fig. 2, the two sides of a foundation trench of a filtering pond are respectively provided with gabions, the gabions are uniformly filled in the gabions in a layered mode, the layered thickness is controlled to be 30cm +/-2 cm, the gabions are covered after top fillers are laid and leveled, and a water filtering gabion A10 and a water filtering gabion B11 are formed, wherein in the process of filling the water filtering gabion A10, the position of a water outlet of a prefabricated rain ditch 7 is measured and placed on the side face of the gabion, a pre-embedded pipe 1001 is embedded according to the measured position of the water outlet of the prefabricated rain ditch 7, and the fillers near the pre-embedded pipe 1001 are lightly compacted by a hand hammer;

referring to fig. 3, a permeable geotextile 12 is laid between a water filtering gabion A10 and a water filtering gabion B11, the permeable geotextile 12 is wrapped to the elevation position of planting soil B402 and fixed, an adjusting layer 404 is filled in layers and drainage blind pipes B405 are pre-buried in the layers, when the adjusting layer 404 is filled in layers, the thickness of each layer is controlled to be 15-20 cm, the thickness of each layer is adjusted by a manual shovel, a filter layer 403 is laid on the adjusting layer 404 and is filled with the planting soil B402, the thickness of the filter layer 403 is controlled to be 50-100 mm, the depth of the planting soil B402 is controlled to be 400-600 mm, and the layered filling thickness is controlled to be within 300 mm.

S2, constructing a prefabricated rain-spraying ditch 7 and a prefabricated water-permeable step 8: referring to fig. 4, excavating a rain ditch foundation groove according to the position of an embedded pipe 1001, leveling and compacting, paving a sand cushion layer on the upper portion of the foundation groove, building prefabricated rain ditches 7 section by section according to a sequence from bottom to top, and paving prefabricated permeable steps 8 on the upper portions of the prefabricated rain ditches 7 according to a sequence from bottom to top; as shown in fig. 5, the two sides and the top of the prefabricated deluge trench 7 are provided with a rabbet, the prefabricated deluge trench 7 is laid flatly when being laid, so that the prefabricated deluge trench 7 on the upper layer is joggled with the prefabricated deluge trench 7 on the lower layer through the rabbet, the rabbets are stably beaten by a rubber hammer, after the prefabricated deluge trench 7 is maintained for 7 days, as shown in fig. 6, the cross section of the prefabricated water-permeable step 8 is in an L shape, and the prefabricated water-permeable step 8 is embedded and fixed in the rabbet at the top of the prefabricated deluge trench 7.

S3, constructing a terrace type revetment 2: referring to fig. 7, the permeable geotextile 12 is laid on both sides of the prefabricated permeable step 8, and the bank slope broken stone 205 is layered-paved and rolled on the permeable geotextile 12; the permeable geotextile 12 is laid from the top of the slope to the bottom of the slope by adopting a manual rolling and laying mode; the layered paving thickness of the bank slope broken stone 205 is controlled within 200mm, the compaction degree is not less than 95%, and the manual paving and rolling are adopted for the bank slope broken stone 205 near the rain-drenching ditch;

referring to fig. 8, two rows of living timber piles 203 are driven on the shore slope crushed stone 205, a gap is reserved between the bottom row of living timber piles 203 and a water filtering gabion A10, when the living timber piles 203 are driven, each timber pile is measured and placed on the shore slope crushed stone 205 to be driven, then an excavator is put in place, after the living timber piles 203 are righted, an excavator bucket of the excavator is turned over to press the living timber piles 203 into the shore slope crushed stone 205, after the pressing is stable, pile heads of the living timber piles 203 are hit by the back of the excavator bucket, and the living timber piles 203 are vertically driven into the shore slope crushed stone 205 to the designed depth;

referring to fig. 9 and 10, backfill 204 and a plant-growing fiber blanket 201 are sequentially constructed on the shore slope broken stones 205, the backfill 204 is constructed by adopting a mechanical-matched manual mode to be paved in a layered mode and tamped in a layered mode, the paving thickness of each layer cannot exceed 25 cm-30 cm, each layer is compacted for 3-4 times, the compaction degree is not less than 95%, and the backfill is finished according to the designed gradient when being backfilled to the top layer; when the plant fiber blanket 201 is constructed, the plant fiber blanket 201 is laid in the direction from the top of a slope to the toe of the slope, the plant fiber blanket 201 should be smoothly and tightly spread, the lap joint width between the plant fiber blankets 201 is not less than 10cm, the top, the bottom and the lap joint part of the plant fiber blanket 201 are firmly fixed by the anchor bolts 202, and the folding cover part is reserved, and the use amount of the anchor bolts 202 is every 1m²Not less than 3, then the prepared plant fiber blanket 201 is folded and covered on the side surface of the backfill soil 204 and is fixed by the anchor 202.

S4, constructing a hydrophilic footpath 3: referring to fig. 11, a prefabricated water-permeable pavement board 301 is laid at a gap between a bottom row living timber pile 203 and a water-filtering gabion a10 to form a hydrophilic pavement 3, during construction, a sand leveling layer is laid on the upper portion of a bank slope gravel 205 in a layered mode and water is sprayed densely, then the prefabricated water-permeable pavement board 301 is laid on the sand leveling layer one by one, the joints between the water-permeable pavement boards 301 are filled with sand, and after the joints are filled with sand, a small-sized vibration roller mill is used for rolling for 2-3 times.

S5, constructing a grass planting drainage ditch 1: referring to fig. 12, digging grass planting drainage ditch grooves;

referring to fig. 13, the side of the grass planting drainage ditch close to water is tightly attached to a prefabricated rain-drop ditch 7 to build a prefabricated catchment ridge 6, and the side of the grass planting drainage ditch close to water is tightly attached to a terrace type revetment 2 to build a prefabricated overflow ridge 5; referring to fig. 14, the two sides of the prefabricated weirs 5 are provided with the rabbet, the adjacent prefabricated weirs 5 are engaged through the rabbet on the two sides of the prefabricated weirs 5, and the prefabricated weirs 5 are provided with the spillway 501 at the position higher than the terrace-type revetment 2; referring to fig. 15, the two sides and the top of a prefabricated catchment ridge 6 are provided with grooves and tongues, the prefabricated catchment ridge 6 is occluded with the grooves and tongues on the two sides of an adjacent prefabricated overflow ridge 5 through the grooves and tongues on the two sides, the prefabricated catchment ridge 6 is provided with a catchment 601 communicated with a prefabricated rain-spraying ditch 7, one side, away from the prefabricated rain-spraying ditch 7, of the catchment 601 is provided with a filter screen 602, when the prefabricated overflow ridge 5 and the prefabricated catchment ridge 6 are built, the mounting position line of the prefabricated overflow ridge 5 and the prefabricated catchment ridge 6 is measured and placed on the side, close to water, of a groove of a grass drainage ditch, cement mortar is mixed for laying, the thickness of the mortar is 30mm, the prefabricated overflow ridge 5 and the prefabricated catchment ridge 6 are built section by section according to the position of a line, cement mortar pointing is timely adopted after the building, and wet-process curing is carried out;

referring to fig. 16, the permeable geotextile 12 is laid at the bottom and the inner wall of the grass planting drainage ditch groove, drainage ditch broken stones 102 are constructed on the upper portion of the permeable geotextile 12, a drainage blind pipe A103 is buried, planting soil A101 is filled on the upper portion of the drainage ditch broken stones 102, the filling thickness of the planting soil A101 is 10-20 cm, a prefabricated permeable pedal 9 connected with a prefabricated permeable step is laid above the planting soil A101 after the filling of the planting soil A101 is completed, and the prefabricated permeable pedal 9 is embedded and fixed at a rabbet at the top of the prefabricated catchment ridge 6.

Finally form as figure 17 ~ 20 natural type bank slope protective structure based on sponge city theory, this structure has formed the multistage natural type bank slope protection of "grass planting escape canal + terraced field formula shore protection + hydrophilic pavement + filtration pond", and its theory of operation is: the grass planting drainage ditch 1 has the functions of water purification, water storage, drainage and water supply, reduces the maintenance cost of vegetation, has low consumption cost, can permeate redundant rainwater to the underground by the gravel layer with good water permeability in rainy days to achieve the function of water storage, can discharge the redundant rainwater to a bank slope through an overflow port, and can discharge the rainwater through a drainage blind pipe and a prefabricated rain-drenching ditch in time when rainstorm attacks, thereby facilitating water purification and water transportation; the bank slope broken stone 205 filled at the bottom of the terrace type bank protection 3 can store and purify partial rainwater, the living wood piles are arranged in the bank slope broken stone 205 and are arranged in the backfill soil, so that the side slope is effectively relieved and the soil body loss is prevented, the plant fiber blanket laid on the upper part of the broken stone can fully exert the water retention property of natural plant fiber, 20-25% of rainwater or irrigation water is retained, on the other hand, the reinforcement and slope protection effects are realized through the shaping net on the outer layer of the plant fiber blanket, and the stability of the slope protection is improved; the filter pond 4 is planted with the hygrophyte combination plants, on one hand, rainwater can be collected and forms a retention water tank 401, so that rainwater can be purified, and rainwater collection, infiltration and recycling are realized; on the other hand, the landscape effect of more water storage and more green without water is realized. The two sides of the filtering pond 4 are provided with water filtering gabions, and the gabions are filled with stones, so that the water quality exchange between river water 13 and revetments is facilitated; meanwhile, a biological membrane can be hung, so that a certain purification effect is achieved; in addition, the porous structure of the gabion can provide a habitat channel, and is beneficial to the reproduction of small aquatic organisms.

The present invention has been described in detail with reference to the embodiments, but the description is only for the preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.

Claims

1. A construction method of a natural bank slope protection structure based on a sponge city idea is characterized by comprising the following steps: which comprises the following steps:

s1, construction of a filtering pond (4): excavating a filtering pond foundation groove at the foot part of a river bank and tamping the filtering pond foundation groove, respectively installing gabions at two sides of the filtering pond foundation groove, uniformly and hierarchically filling the gabions to form a water filtering gabion A (10) and a water filtering gabion B (11), burying a pre-buried pipe (1001) in the filling process of the water filtering gabion A (10), paving a permeable geotextile (12) between the water filtering gabion A (10) and the water filtering gabion B (11), hierarchically filling a regulation layer (404) and pre-burying a drainage blind pipe B (405) therein, paving a filter layer (403) on the regulation layer (404) and filling planting soil B (402);

s2, constructing a prefabricated rain-spraying ditch (7) and a prefabricated water-permeable step (8): excavating a rain-drop ditch foundation groove according to the position of the embedded pipe (1001), leveling and compacting, paving a sand cushion layer on the upper part of the foundation groove, building the prefabricated rain-drop ditches (7) section by section according to the sequence from bottom to top, and paving the prefabricated water-permeable steps (8) on the upper parts of the prefabricated rain-drop ditches (7) according to the sequence from bottom to top;

s3, constructing a terrace type revetment (2): paving permeable geotextiles (12) on two sides of the prefabricated permeable step (8), performing layered paving and rolling operation on bank slope broken stones (205) on the permeable geotextiles (12), at least driving two rows of living wood piles (203) on the bank slope broken stones (205), reserving a gap between the bottom row of living wood piles (203) and the water filtering gabion A (10), and sequentially constructing backfill soil (204) and a vegetation fiber blanket (201) on the bank slope broken stones (205);

s4, construction of the hydrophilic footpath (3): laying a prefabricated water permeable footpath plate (301) at a gap between the bottom row living timber pile (203) and the water filtering gabion A (10) to form a hydrophilic footpath (3);

s5, constructing the grass planting drainage ditch (1): excavation grass planting escape canal slot, the grass planting escape canal slot is faced water one side and is hugged closely prefabricated rain-drench ditch (7) and builds prefabricated catchment bank (6), and the grass planting escape canal slot is faced water one side and is hugged closely terraced fields formula shore protection (2) and builds prefabricated overflow bank (5), prefabricated overflow bank (5) are equipped with gap (501) in the position that is higher than terraced fields formula shore protection (2), be equipped with catchment mouth (601) with prefabricated rain-drench ditch (7) intercommunication on prefabricated catchment bank (6), prefabricated rain-drench ditch (7) one side is kept away from in catchment mouth (601) and is equipped with filter screen (602), then lays geotechnological cloth (12) that permeates water in the bottom and the inner wall of grass planting escape canal slot, at geotechnological cloth (12) upper portion construction escape canal (102) that permeate water and bury drainage blind pipe A (103) underground, fills planting soil A (101) in escape canal rubble stone (102) upper portion.

2. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: and in the step S1, when the gabion is filled, the layering thickness is controlled to be 30cm +/-2 cm, and the gabion cover sealing is carried out after the top filling is paved and leveled, so that the water filtering gabion A (10) and the water filtering gabion B (11) are formed.

3. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: in the step S1, in the process of filling the water-filtered gabion A (10), the position of the water outlet of the prefabricated rain ditch (7) is measured and placed on the side face of the gabion, the embedded pipe (1001) is buried according to the measured position of the water outlet of the prefabricated rain ditch (7), and the filler near the embedded pipe (1001) is lightly compacted by a hand hammer.

4. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: in the step S1, when the permeable geotextile (12) is laid between the water filtering gabion A (10) and the water filtering gabion B (11), the permeable geotextile (12) is reversely wrapped to the elevation position of the planting soil B (402) and fixed; when the storage layer (404) is laid, the thickness of each layer is controlled to be 15-20 cm, and the thickness of each layer is manually arranged by a shovel; the thickness of the filter layer (403) is controlled to be 50-100 mm; the depth of the planting soil B (402) is controlled to be 400-600 mm, and the layered filling thickness is controlled to be within 300 mm.

5. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: the two sides and the top of the prefabricated rain ditch (7) are provided with grooves and tongues; in the step S2, the prefabricated deluge ditch (7) is laid flatly, so that the prefabricated deluge ditch (7) on the upper layer is joggled with the prefabricated deluge ditch (7) on the lower layer through the rabbet, and is beaten stably by a rubber hammer; after the prefabricated rain-sprinkling trench (7) is maintained for 7d, the prefabricated water-permeable step (8) is embedded and fixed in a rabbet at the top of the prefabricated rain-sprinkling trench (7).

6. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: in the step S3, the permeable geotextile (12) is paved from the top of the slope to the bottom of the slope in a manual rolling and paving mode; the layered paving thickness of the bank slope crushed stone (205) is controlled within 200mm, the compaction degree is not less than 95%, and the bank slope crushed stone (205) near the rain-drenching ditch is manually paved and rolled.

7. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: when the living timber piles (203) are driven in the step S3, each timber pile driving position is measured and placed on the bank slope broken stone (205), then the excavator is put in place, after the living timber piles (203) are righted, the bucket of the excavator is turned upside down to press the living timber piles (203) into the bank slope broken stone (205), after the excavator is pressed stably, the pile heads of the living timber piles (203) are hit by the back of the bucket, and the living timber piles (203) are vertically hit into the bank slope broken stone (205) until the design depth is reached.

8. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: in the step S3, the backfill (204) construction adopts a mode of mechanical cooperation and manual work for layered paving and layered tamping, the paving thickness of each layer is not more than 25-30 cm, each layer is compacted for 3-4 times, the compaction degree is not less than 95%, and the backfill is finished according to the designed gradient when backfilling to the top layer;

when the plant fiber blanket (201) is constructed, the plant fiber blanket (201) is laid in the direction from the top of a slope to the toe of the slope, the plant fiber blanket (201) should be smoothly and tightly spread, the lap joint width between the plant fiber blankets (201) is not less than 10cm, the top, the bottom and the lap joint part of the plant fiber blanket (201) are firmly fixed by an anchor bolt (202), a folding cover part is reserved, and the use amount of the anchor bolt (202) is 1m per time²Not less than 3, then the reserved plant fiber blanket (201) is folded and covered on the side surface of the backfill soil (204) and fixed by an anchor bolt (202).

9. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: and S4, when the hydrophilic pavement (3) is constructed, laying a sand leveling layer on the upper part of the bank slope gravel (205) layer by layer, spraying water to the sand leveling layer to be dense, then laying prefabricated water-permeable pavement plates (301) on the sand leveling layer block by block, filling and filling sand into joints among the water-permeable pavement plates, and rolling the joints for 2-3 times by using a small vibration roller mill after the sand filling is finished.

10. The construction method of the natural bank slope protection structure based on the sponge city idea as claimed in claim 1, wherein: in the step S5, grooves and tongues are arranged on two sides of the prefabricated weirs (5), grooves and tongues are arranged on two sides and the top of the prefabricated catchment ridges (6), when the weirs (5) and the prefabricated catchment ridges (6) are prefabricated, the adjacent prefabricated weirs (5) are engaged with each other through the grooves and tongues on two sides of the prefabricated weirs (5), the prefabricated catchment ridges (6) are engaged with the grooves and tongues on two sides of the adjacent prefabricated weirs (5) through the grooves and tongues on two sides, when the prefabricated weirs (5) and the prefabricated catchment ridges (6) are built, the mounting position lines of the prefabricated weirs (5) and the prefabricated catchment ridges (6) are measured on the side, close to water, of the grooves of the grass planting drainage ditches, cement mortar is mixed with the laid bottom, the mortar is 30mm thick, the prefabricated weirs (5) and the prefabricated catchment ridges (6) are built section by section according to the setting-out positions, after the building, the jointing is timely adopted, and wet-process health maintenance is carried out; the filling thickness of the planting soil A (101) is 10-20 cm, a prefabricated water permeable pedal (9) connected with a prefabricated water permeable step is laid above the planting soil A (101) after the filling of the planting soil A (101) is completed, and the prefabricated water permeable pedal (9) is embedded and fixed at a rabbet at the top of the prefabricated catchment sill (6).