CN113322984A

CN113322984A - Quick repairing structure for shallow landslide of soil slope with more than two levels and construction method thereof

Info

Publication number: CN113322984A
Application number: CN202110631834.2A
Authority: CN
Inventors: 张军辉; 周勤伟; 黎峰; 张石平
Original assignee: Changsha University of Science and Technology
Current assignee: Changsha University of Science and Technology
Priority date: 2021-06-07
Filing date: 2021-06-07
Publication date: 2021-08-31
Also published as: WO2022083785A1; ZA202205161B

Abstract

The invention discloses a quick repairing structure for shallow landslide of a soil slope with more than two levels and a construction method thereof, wherein the repairing structure comprises the following components: the method comprises the steps of excavating a slumping part of a landslide body, filling a plurality of layers of backfill bagged soil on the steps, paving geogrids at the bottom of each layer of backfill bagged soil, reversely wrapping reserved parts of the geogrids along the backfill bagged soil on the upper parts of the geogrids, stretching the backfill bagged soil to a required tensile strength, fixing the geogrids on the top surfaces of the backfill bagged soil through U-shaped nails to form reverse wraps, fixedly connecting the reversely wrapped geogrids with the geogrids adjacent to the upper layers through the U-shaped nails, and fixing the reversely wrapped geogrids and the geogrids adjacent to the upper layers on the corresponding top surfaces of the backfill bagged soil, and implanting a plurality of reinforcing steel bars into the bottom of a reinforcement body formed by combining the backfill bagged soil and the geogrids. The restoration structure has a supporting function, and simultaneously achieves energy dissipation through the expansion deformation of the self deformation on soil in the slope, so that the restoration structure is good in restoration effect, simple and convenient to construct, low in personnel technical requirement, short in construction period, few in machinery, low in risk, low in cost and environment-friendly.

Description

Quick repairing structure for shallow landslide of soil slope with more than two levels and construction method thereof

Technical Field

The invention belongs to the technical field of slope engineering, and relates to a quick repairing structure for shallow landslides of soil slopes with more than two levels and a construction method thereof.

Background

The traditional treatment method of the shallow landslide generally adopts a masonry retaining wall rigid supporting structure, and the method needs to use various machines and a large number of workers for construction. For the landslides of the second grade and above, because the position is higher, the construction site is narrow and small, various construction machines (such as an excavator, a road roller and the like) cannot be used, the traditional stone masonry treatment method can only manually excavate landslide soil bodies, and the landslide soil bodies are hoisted to a soil transporting vehicle on the ground by a crane and transported to a waste soil site; then, the bought rock blocks and concrete are transported to the landslide, the rock blocks and concrete are hung by a crane, and landslide bodies are built and repaired on the side slopes manually, as shown in fig. 1.

In order to overcome the construction difficulties of the traditional rigid repair technology and reduce the transportation of machinery and fillers, a composite repair structure and a construction method thereof need to be provided.

Disclosure of Invention

In order to solve the problems, the invention provides a quick repairing structure for shallow landslides of soil slopes with more than two levels, which has the advantages of good repairing effect, simple and convenient construction, low personnel technical requirement, short construction period, less machinery, low risk, low cost and environmental protection, and can realize energy dissipation through the expansion deformation of soil in the slopes by self deformation while playing a role of supporting.

The invention also aims to provide a construction method for quickly repairing the shallow landslide of the soil slope with more than two levels.

The invention adopts the technical scheme that a structure for quickly repairing shallow landslides of soil slopes with more than two levels is characterized in that steps are excavated at the landslide part of a landslide body, a plurality of layers of backfilling bagged soil are filled on the steps, each layer of backfilling bagged soil of each compaction layer is staggered horizontally and vertically, geogrids are laid at the bottom of each layer of backfilling bagged soil, the reserved part of each geogrid is reversely wrapped along the backfilling bagged soil at the upper part of the geogrid and tensioned to the required tensile strength, the geogrid is fixed on the top surface of the backfilling bagged soil through U-shaped nails to form a reverse wrapping, the reversely wrapped geogrid and the geogrid adjacent to the upper layer are fixedly connected through the U-shaped nails and are fixed on the corresponding top surface of the backfilling bagged soil, so that the geogrid adjacent to the two layers and the backfilling bagged soil are combined into a reinforced body; and a plurality of reinforcing steel bars are implanted into the bottom of the reinforced body formed by the backfill bagged soil and the geogrid.

Furthermore, the steel bars are arranged at a distance of 1m along the longitudinal direction of the landslide body, 1 row of steel bars are implanted into 1m of backfilling along the height direction, the lower parts of the steel bars are driven into a natural soil body for 1.5m, and the upper parts of the steel bars enter the backfilling bagged soil for at least 0.5 m.

Furthermore, the geogrid at the bottom of the backfill bagged soil extends to the step, and the step is used as an anchoring plane of the geogrid.

Furthermore, the horizontal plane of the step and the top surface of the backfill bag soil of the corresponding layer form a wider working plane.

Furthermore, the tensile strength of the geogrid is more than or equal to 35kN/m, and the elongation is less than 10%.

Furthermore, the geogrids are connected through connecting rods along the longitudinal overlapped part of the landslide body.

Furthermore, 3-4 rows of backfill bagged soil are paved according to the width of each layer of platform.

Furthermore, the bottom of the repair structure is provided with a slope bottom drainage ditch, and the top of the repair structure is provided with a slope top intercepting drainage ditch.

Further, the slope of the restoration structure is cultivated to form a backfill cultivation soil layer with the thickness not less than 20 cm.

A construction method for quickly repairing a structure of a shallow landslide layer of a soil slope with more than two levels specifically comprises the following steps:

s1: excavating a side slope; construction lofting is carried out according to the cross section of the structural design, the horizontal width and the depth of the side slope and foundation excavation are determined by taking the slope toe of the designed side slope as a starting point, steps are excavated at the landslide part of the landslide body, and excavated earth is stacked at the nearby position and is used for preparing backfill bagged soil;

s2: tamping a foundation; tamping the surface of the substrate by a small-sized tamper, wherein the compaction degree of the substrate is controlled to be more than 90%;

s3: spreading the geogrid; cutting the geogrid, wherein the blanking length of the geogrid is the sum of the reinforcement length, the turn-up length and the overlapping length; marking the end position of the geogrid laying; paving in a width-dividing manner along the longitudinal direction of the side slope, reserving a reverse bag, and keeping the stress direction of the geogrid to be consistent with the cross section direction of the roadbed during paving, namely the stress direction of the geogrid is vertical to the longitudinal direction of the side slope; tensioning the spread geogrid, and anchoring the geogrid on the top of the base surface by using U-shaped nails; overlapping parts of two longitudinally adjacent geogrids are mutually overlapped, and the two adjacent geogrids are fixed on the top of the base surface by U-shaped nails;

s4: backfilling filler, paving and rolling; after the geogrid is laid, backfilling bagged soil is laid in layers, loose laying is carried out, the thickness of each layer of loose laying is not more than 30cm, manual preliminary compaction is carried out, compaction is pushed from outside to inside along the longitudinal direction, manual compaction is carried out near the side slope surface outside the reinforcement body, and the compaction degree is not lower than 80%; paving a layer of smooth wood board on the backfill bagged soil, and rolling and tamping the backfill bagged soil longitudinally from outside to inside by using a small-sized soil compactor until the compactness is not less than 85%;

s5: reversely wrapping and anchoring the geogrid; after the backfill bagged soil is rolled and tamped, reversely wrapping the reserved geogrid along the repaired side slope, tensioning the geogrid to the required tensile strength, and anchoring the geogrid on the top surface of the backfill bagged soil by using U-shaped nails; implanting a plurality of steel bars at the bottom of a reinforced body formed by the combination of the backfilled bagged soil and the geogrid;

s6: continuing the construction of the next compacted layer according to the steps S3-S7, connecting the geogrid of the next layer of reverse wrapping with the geogrid of the previous layer by using U-shaped nails to form a reinforcement body, and reinforcing the backfill bagged soil;

s7: slope surface treatment; cultivating a backfill cultivation soil layer with the thickness not less than 20cm on the slope surface, and greening in time.

The invention has the beneficial effects that:

1. the repairing effect is good. The composite repairing structure belongs to a flexible structure, achieves the energy eliminating effect through self deformation, and is more suitable for the deformation of the side slope soil body than the traditional structure (rigid structures such as masonry, concrete wall and the like).

2. The construction is simple and convenient, and the construction period is shortened. The construction process and the working procedure of the invention are simple and easy to implement, the number of the ring sections which need to be coordinated and matched with each other is reduced, the working efficiency on the slope is improved, and the landslide emergency time is shortened.

3. The machine is few, and the risk is low. The repairing structure is constructed on the soil slope with more than two levels, only manual work and a small-sized soil rammer are needed to operate on the slope, the use of large-sized machinery is reduced, the hazard source is reduced, and the construction risk is reduced.

4. Saving materials and cost. The repairing structure fully utilizes the soil body of the landslide to backfill, namely, the soil body is dug and used without purchasing stones outside, so that the material and cost are saved, the processes of transporting the stones and the earthwork by using the traditional structure are omitted, the pollution of noise, dust, waste gas and the like in the construction process can be reduced to a great extent, meanwhile, the field management is simple and convenient, the labor cost and the time cost of mechanical coordination are reduced, a large amount of oil mass and power consumption are saved, the waste soil and occupied land are reduced, the energy is saved, the emission is reduced, and the environment is protected.

5. The invention adopts a step method to manually excavate layer by layer and stack the bagged landslide soil body nearby, the geogrid is reinforced and reversely wrapped, the small-sized soil rammer is vibrated and compacted, and the reinforcing steel bars are implanted at intervals to enhance the connection with the original side slope, thereby improving the stability of the side slope, simultaneously improving the construction safety, and being environment-friendly and obvious in economic benefit.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a field diagram of a conventional treatment method for shallow landslides.

Fig. 2 is a schematic structural diagram of an embodiment of the present invention.

Fig. 3 is a schematic view showing the connection of the geogrid, the staple and the connecting rod according to the embodiment of the invention.

FIG. 4 is a flow chart of the construction of an embodiment of the present invention.

In the figure, 1, a landslide body, 2, geogrids, 3, backfilled bagged soil, 4, a backfilled cultivation soil layer, 5, steps, 6, reinforcing steel bars, 7, connecting rods, 8, a slope top intercepting ditch, 9, a slope bottom draining ditch and 10, U-shaped nails are arranged.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention embodiment relates to a structure for quickly repairing shallow landslide of a soil slope with more than two levels, which comprises a geogrid 2, backfilling bagged soil 3, implanted reinforcing steel bars 6, backfilling cultivated soil layers 4 and steps 5, wherein the steps 5 are excavated at a slumping part of a landslide body 1, a plurality of layers of backfilling bagged soil 3 are filled on the steps 5, the backfilling bagged soil 3 of each compaction layer is staggered horizontally and vertically, and soil bags are tightly connected in the vertical direction by matching with the steps 5 of each layer; geogrid 2 is laid at the bottom of each layer of backfill bagged soil 3, the reserved portion of each geogrid 2 is reversely wrapped and tensioned to required tensile strength along the backfill bagged soil 3 on the upper portion of the geogrid 2, the geogrid 2 is fixed to the top surface of the backfill bagged soil 3 through U-shaped nails 10 to form a reverse wrapping, the reversely wrapped geogrid 2 and the geogrid 2 adjacent to the upper layer are fixedly connected through the U-shaped nails 10 and are fixed to the top surface of the corresponding backfill bagged soil 3, the geogrid 2 adjacent to the two layers and the backfill bagged soil 3 are combined to form a reinforcement body, the reinforcement effect is achieved on the backfill bagged soil 3, the safety coefficient is increased, and landslides are not prone to occurring.

In some embodiments, a plurality of reinforcing steel bars 6 are implanted at the bottom of the reinforced body formed by the combination of the backfill bagged soil 3 and the geogrid 2, the reinforcing steel bars 6 are implanted at intervals of 1m along the longitudinal direction of the landslide body 1, 1 row of reinforcing steel bars 6 are implanted at every backfill 1m along the height direction, the natural soil body is driven into the lower portion of each reinforcing steel bar 6 by 1.5m, the backfill bagged soil enters the backfill bagged soil 3 at the upper portion by at least 0.5m, and the backfill bagged soil is connected with the natural slope surface, so that the integral skid resistance of the support body.

In some embodiments, the geogrid 2 at the bottom of the backfill bag soil 3 extends to the step 5, and the step 5 serves as an anchoring plane for the geogrid 2, so that the geogrid 2 is connected with the non-landslide soil slope, not only anchored on the backfill bag soil 3, and the better tensioning effect is achieved after the bag is turned over. Meanwhile, the step 5 provides a fixed plane for embedding the steel bars, so that the connection between the backfill bagged soil and the non-collapse side slope is firmer.

In some embodiments, the horizontal plane of the step 5 and the top surface of the backfill bagged soil 3 of the corresponding layer form a wider working plane, so that convenience is provided for laying, tamping and reverse construction of each layer of backfill soil, construction quality is improved, and construction safety is guaranteed.

The longitudinal overlapped parts of the geogrids 2 along the sliding mass 1 are connected through the connecting rods 7, so that the integrity of the geogrids 2 is guaranteed. The tensile strength of the geogrid 2 is more than or equal to 35kN/m, and the elongation rate<10 percent, the connecting rod 7 is made of plastic or steel bar, and the U-shaped nail 10 is made of plastic or steel bar

The steel bar (the steel bar with the nominal diameter of 6 mm) is manufactured on site.

The bottom of the landslide part repairing structure is provided with a slope bottom drainage ditch 9, the top of the landslide part repairing structure is provided with a slope top intercepting drainage ditch 8, a backfill cultivation soil layer 4 with the thickness not less than 20cm is cultivated on the slope, and greening is carried out in time.

3-4 rows of backfill bagged soil 3 are generally paved according to the width of each layer of platform, the backfill bagged soil is closely arranged when being loosely paved, the height of the tamped soil bags is reduced, the width is increased, the soil bags are arranged more closely, meanwhile, the geogrid 2 is tensioned by a U-shaped nail 10 when being reversely wrapped, enough fixing force is applied to the backfill bagged soil 3 in the transverse row, and the expansive force generated by the backfill bagged soil 3 due to the increase of rainfall water absorption volume can be resisted.

The embodiment of the invention provides a construction method for quickly repairing a shallow landslide of a soil slope with more than two levels, which is shown in figure 4 and specifically comprises the following steps:

s1: excavating a side slope; construction lofting is carried out according to the cross section of the structural design, the horizontal width and the depth of the side slope and foundation excavation are determined by taking the design side slope toe as a starting point, steps 5 are excavated on the landslide part of the landslide body 1, and if collapse exceeding the design range occurs in the excavation process, all steps are removed; the excavated earthwork is stacked at a nearby position and used for preparing backfill bagged soil 3; the backfill bagged soil 3 adopts a soil engineering bag, the surface of the soil engineering bag is smooth and compact, and the surface of the plant growing bag is provided with a plurality of holes, so that the later growth and development of plants are facilitated; the backfill bagged soil 3 can contain various soil fillers, namely red clay in the embodiment of the invention.

S2: tamping a foundation; tamping the surface of the substrate by a small-sized tamper, rolling for 3-5 times back and forth, and controlling the compaction degree of the substrate to be more than 90%.

S3: paving the geogrid 2;

s31: cutting the geogrid 2 according to the length of 2.5m, wherein the blanking length of the geogrid 2 is the sum of the reinforcement length, the turn-up length and the overlapping length;

s32: laying and lofting, and marking the end position of the geogrid 2; paving the earthwork grid in a width manner along the longitudinal direction of the side slope, wherein each width is paved for 1m, a reverse bag of 1.5m is reserved, and the stress direction of the earthwork grid 2 is consistent with the cross section direction of the roadbed when the earthwork grid is paved, namely the stress direction of the earthwork grid 2 is vertical to the longitudinal direction of the side slope; the spread geogrid 2 is tensioned and anchored on top of the ground plane with U-shaped nails 10. Overlapping parts of two adjacent longitudinal geogrids 2 are mutually overlapped, in order to ensure the integrity of the geogrids 2, the overlapping width is not less than 15cm, and the two adjacent geogrids 2 are fixed on the top of the base surface by U-shaped nails 10.

S4: backfilling filler, paving and rolling; after the geogrid 2 is laid, backfilling bagged soil 3 is laid layer by layer, 3 layers are loosely laid, the thickness of each layer of loose soil is not more than 30cm, and manual preliminary treading is carried out; the construction machinery is strictly forbidden to directly run on the geogrid 2, compaction is pushed from outside to inside along the longitudinal direction, and manual compaction is adopted in the range close to the slope surface at the outer side of the reinforced body (the reinforced body formed by combining the backfill bagged soil 3 and the geogrid 2), so that the compaction degree is not lower than 80%.

Rolling, tamping and backfilling bagged soil 3; the surface of the backfill bagged soil 3 is porous, and the soil bag is easy to be broken and difficult to advance by directly rolling and tamping the surface of the backfill bagged soil 3 by a soil compactor, so that the tamping effect is influenced due to nonuniform tamping. Therefore, a layer of flat wood board is laid on the loosely laid backfill bagged soil 3 before tamping, and the backfill bagged soil 3 is prevented from being damaged and difficult to push by a tamper in the tamping process; and (3) rolling and tamping each layer of loosely paved and backfilled bagged soil 3 longitudinally from outside to inside by using a small-sized soil compactor, wherein the rolling is carried out for at least 3 times back and forth until the compaction degree is not less than 85%, and the height of each layer of backfilled and bagged soil 3 is 25-30 cm.

S5: reversely wrapping and anchoring the geogrid 2; turning over the geogrid 2; and compacting the backfilled bagged soil 3, reversely wrapping the reserved geogrid 2 along the repaired side slope, tensioning to the required tensile strength, and anchoring the geogrid on the top surface of the compacted backfilled bagged soil 3 by using U-shaped nails 10.

And after tamping the first layer of backfill soil at the bottom of the reinforcement body formed by combining the backfill bagged soil 3 and the corresponding geogrid 2, implanting 1 row of reinforcing steel bars 6 on the surface of the reinforcement body, wherein the longitudinal distance between the reinforcing steel bars 6 is 1m, and implanting 1 row of reinforcing steel bars in each backfill 1m along the height direction. The lower part of the steel bar is driven into a natural soil body by 1.5m, and the upper part of the steel bar enters a reinforcement body by 0.5 m; the backfilling bagged soil 3 is connected with the natural slope surface, so that the integral skid resistance of the support body is increased.

S6: and (5) continuing the construction of the next compacted layer according to the steps S3-S7, connecting the geogrid 2 which is reversely wrapped at the next layer with the geogrid 2 at the previous layer by using the U-shaped nails 10 to form a reinforced body, and reinforcing the backfilled bagged soil, so that the safety coefficient is increased, and the landslide is not easy to generate.

S7: slope surface treatment; slope treatment and the geogrid 2 are carried out layer by layer in a reverse wrapping mode, a backfill cultivation soil layer 4 with the thickness not less than 20cm is cultivated on the slope, greening is carried out in time, the service life of the geogrid is prevented from being influenced by ultraviolet rays, and meanwhile rain washing is prevented.

The composite repairing structure and the traditional repairing structure are respectively adopted to repair two similar-scale shallow landslides of the same slope, and the ratio of the construction period, the personnel and the machinery of the two shallow landslides is shown in table 1:

TABLE 1 comparison of the composite repair construction of the present invention with a conventional repair construction

Repairing structural types	Personnel request	Number of persons	Construction period	Machine with a movable working part
					Tradition of	High-grade worker	8 persons	17 days	Excavator, forklift, planer, road roller and crane
The invention	Common worker	7 persons	13 days	Small-sized rammers, occasionally using cranes

As a result, it was found that: compared with the traditional repairing construction period, the construction period of the composite repairing structure is saved by 24%, the possibility of secondary collapse dangerous situation of the collapse side slope due to unloading relaxation can be reduced by shortening the construction period, and the safety and the stability of the side slope structure are improved. The composite type repairing structure construction of the invention needs 7 common workers on average, and the common workers respectively participate in the work of digging a slope, bagging, tamping and the like, the traditional repairing structure construction needs 8 advanced workers on average, and the dispatching and the operation management of site construction machinery are considered while the stone building work is carried out. The site construction of the composite repairing structure can be completed only by matching the manual work and the small-sized rammer on the slope, and occasionally, a crane is called to convey materials such as geogrids, reinforcing steel bars and the like to the landslide body; compared with the traditional repairing structure, the whole process of large-scale machines such as excavators, forklifts, planers and road rollers is reduced in the construction process. The reduction of constructors and mechanical equipment removes a plurality of potential hazard sources, fundamentally reduces the hidden danger of construction risk and improves the construction safety. The invention fully utilizes the soil body of the landslide to backfill the reinforced body, namely the reinforced body can be used after being dug and assembled, even if the condition of soil shortage possibly occurs due to tamping of the backfilled reinforced body in the later period, only a part of soil material is needed to be called from a nearby side slope or a waste soil yard, and materials such as rock blocks and the like are not needed to be purchased outside, so that the processes of transporting the rock blocks into and transporting out of the earthwork by the traditional repairing technology are omitted, the waste soil is saved, extra land occupation is not needed, the materials are saved, and the cost in various aspects caused by extra workers, machinery, stone materials purchased outside and transportation of the traditional structure is greatly reduced. According to the invention, the cultivation soil is backfilled on the surface layer of the structure, the plant seeds are sprayed, and the green plants growing for a period of time can effectively prevent water and soil loss, so that the stability of slope restoration is further ensured, and compared with the surface of the traditional structural concrete, the surface of the concrete is more environment-friendly. Links needing mutual coordination and matching in the construction procedure are reduced, the emergency time can be shortened, manpower and material resources are saved, the economic and management cost is saved, and energy and emission are saved.

The existing landslide restoration adopts rigid structures such as anti-slide piles, retaining walls, frame beams and the like to protect poor deformation resistance, and needs higher strength to resist the expansive force of red clay generated due to humidification. The composite restoration structure of the invention uses the geogrid to reinforce and backfill bagged soil, and compacts and turns over the bagged soil in a layering way, uses U-shaped nails for anchoring, and is matched with implanted reinforcing steel bars to connect the backfill soil body and the natural soil body together to form a flexible reinforcement supporting structure with enough thickness; on one hand, the side slope is supported and blocked, and on the other hand, the red clay in the slope is expanded and deformed to dissipate energy through self deformation. The interaction between the geogrids and the backfilled bagged soil, particularly the interconnection and the wrapping between all layers of geogrids, provides sufficient frame hooping effect for the bagged red clay, and is matched with the reinforcing steel bars implanted at intervals to strengthen the connection between the reinforcement body and the natural soil body, so that the reinforcement body can bear a certain deformation without damaging the integral structure, and the cutting slope is supported; simultaneously, the deformation through geogrid reinforcement body makes the red clay release in the slope because of the expansive force that the humidification produced, produces the expansion deformation to the soil body in the slope and plays the energy dissipation effect, avoids leading to the slope to appear wholly or local collapse because of the accumulation of expansion energy, reaches the purpose of "managing bloated with gentle", has solved the problem that traditional restoration structure exists.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims

1. A structure for quickly repairing shallow landslide of soil slope with more than two levels is characterized in that steps (5) are dug at the landslide part of a landslide body (1), a plurality of layers of backfilling bagged soil (3) are filled on the steps (5), the backfilling bagged soil (3) at each layer of each compaction layer are staggered horizontally and vertically, a geogrid (2) is laid at the bottom of each layer of backfilling bagged soil (3), the reserved part of the geogrid (2) is reversely wrapped along the backfilling bagged soil (3) at the upper part of the geogrid (2) and is tensioned to required tensile strength, the geogrid (2) is fixed on the top surface of the backfill bagged soil (3) through the U-shaped nails (10) to form a reverse bag, the reverse bag geogrid (2) is fixedly connected with the geogrid (2) adjacent to the upper layer through the U-shaped nails (10) and is fixed on the top surface of the corresponding backfill bagged soil (3), combining the geogrids (2) adjacent to the two layers and the backfilling bagged soil (3) into a reinforced body; and a plurality of reinforcing steel bars (6) are implanted at the bottom of the reinforcement body formed by the backfill bagged soil (3) and the geogrid (2).

2. The structure for rapidly repairing the shallow landslide of more than two-level soil slope according to claim 1, wherein the steel bars (6) are embedded into 1 row of steel bars (6) every 1m of backfilling along the height direction at a distance of 1m along the longitudinal direction of the landslide body (1), the lower part of the steel bars (6) is driven into the natural soil body for 1.5m, and the upper part of the steel bars enters the backfilling bagged soil (3) for at least 0.5 m.

3. The structure for rapidly repairing shallow landslide of soil slope with more than two levels according to claim 1, wherein the geogrid (2) at the bottom of the backfill bagged soil (3) extends to the step (5), and the step (5) is used as an anchoring plane of the geogrid (2).

4. The structure for rapidly repairing shallow landslide of more than two-level soil slope according to claim 1, wherein the horizontal surface of the step (5) and the top surface of the corresponding layer of backfill bagged soil (3) form a wider working plane.

5. The structure for rapidly repairing shallow landslide of soil slope with more than two levels of soil according to claim 1, wherein tensile strength of the geogrid (2) is more than or equal to 35kN/m, and elongation is less than 10%.

6. The structure for rapidly repairing shallow landslide of soil slope with more than two levels according to claim 1, wherein the overlapping parts of geogrids (2) along the longitudinal direction of the landslide body (1) are connected through connecting rods (7).

7. The structure for rapidly repairing shallow landslide of soil slope with more than two levels according to claim 1, wherein the backfill bagged soil (3) is paved in 3-4 rows according to the width of each layer of platform.

8. The structure for rapidly repairing shallow landslide of more than two-level soil slope according to claim 1, wherein the bottom of the structure is provided with a slope bottom drainage ditch (9), and the top is provided with a slope top intercepting ditch (8).

9. The structure for rapidly repairing shallow landslide of soil slope with more than two levels as claimed in claim 1, wherein the slope of the repairing structure is cultivated with backfill cultivated soil layer (4) with thickness not less than 20 cm.

10. A construction method for quickly repairing a structure of a shallow landslide layer of a soil slope with more than two levels is characterized by comprising the following steps:

s1: excavating a side slope; construction lofting is carried out according to the cross section of the structural design, the horizontal width and the depth of the side slope and foundation excavation are determined by taking the design side slope toe as a starting point, steps (5) are excavated in the landslide part of the landslide body (1), and excavated earthwork is stacked at the nearby position and is used for preparing backfill bagged soil (3);

s3: paving the geogrid (2); cutting the geogrid (2), wherein the blanking length of the geogrid (2) is the sum of the reinforcement length, the turn-up length and the overlapping length; marking the end position of the geogrid (2) laying; paving the earthwork grille (2) in a width-dividing manner along the longitudinal direction of the side slope, reserving a reverse bag, and keeping the stress direction of the earthwork grille (2) consistent with the cross section direction of the roadbed during paving, namely the stress direction of the earthwork grille (2) is vertical to the longitudinal direction of the side slope; tensioning the paved geogrid (2) and anchoring the geogrid on the top of the base surface by using a U-shaped nail (10); overlapping parts of two longitudinal adjacent geogrids (2) are mutually overlapped, and the two adjacent geogrids (2) are fixed on the top of the base surface by U-shaped nails (10);

s4: backfilling filler, paving and rolling; after the geogrid (2) is laid, backfilling bagged soil (3) is laid in layers, loose paving is conducted, the thickness of each layer of loose paving is not more than 30cm, manual preliminary compaction is conducted, compaction is conducted from outside to inside in the longitudinal direction, manual compaction is conducted on the part, close to the slope surface on the outer side of the reinforcement body, and the compaction degree is not lower than 80%; paving a layer of flat wood board on the backfill bagged soil (3), and rolling and tamping the backfill bagged soil (3) from outside to inside along the longitudinal direction by a small-sized soil compactor until the compactness is not less than 85%;

s5: the geogrid (2) is reversely wrapped and anchored; the backfilling bagged soil (3) is rolled and tamped, then the reserved geogrid (2) is reversely wrapped along the repaired side slope and tensioned to the required tensile strength, and a U-shaped nail (10) is used for anchoring the top surface of the backfilling bagged soil (3); implanting a plurality of reinforcing steel bars (6) at the bottom of the reinforcement body formed by the combination of the backfill bagged soil (3) and the geogrid (2);

s6: continuing the construction of the next compacted layer according to the steps S3-S7, connecting the geogrid (2) which is reversely wrapped at the next layer with the geogrid (2) at the previous layer by using U-shaped nails (10) to form a reinforcement body, and reinforcing the backfill bagged soil;

s7: slope surface treatment; cultivating a backfill cultivation soil layer (4) with the thickness not less than 20cm on the slope surface, and greening in time.