阅读说明：本技术 一种泥石流疏导方法 (Debris flow dredging method ) 是由 董云 于丰泽 胡鹏 岳建国 田华 王首智 韩俊 赵国华 任海波 邓弟平 于 2020-06-22 设计创作，主要内容包括：本发明公开了一种泥石流疏导方法,包括S1、根据遥感技术、区域历史水文数据和山体区域地形图,构建山体区域三维模型；S2、根据发生泥石流灾害时的历史数据,分别构建各个山体区域的灾害预测模型；S3、根据灾害预测模型中泥石流灾害的概率进行各个山体区域泥石流等级评定,并将评定后的山体区域等级映射于山体区域三维模型中,包括：S4、对在所述山体区域三维模型中标注为黄色、橙色和红色的山体区域进行防护治理。(The invention discloses a debris flow dredging method, which comprises the steps of S1, constructing a three-dimensional model of a mountain area according to a remote sensing technology, regional historical hydrological data and a mountain area topographic map; s2, respectively constructing a disaster prediction model of each mountain area according to historical data when the debris flow disaster occurs; s3, performing debris flow grade assessment in each mountain area according to the probability of debris flow disasters in the disaster prediction model, and mapping the assessed mountain area grade in a mountain area three-dimensional model, wherein the steps comprise: and S4, performing protective treatment on the mountain areas marked with yellow, orange and red colors in the three-dimensional mountain area model.)

1. A debris flow dredging method is characterized by comprising the following steps:

s1, constructing a three-dimensional model of the mountain area according to the remote sensing technology, the regional historical hydrological data and the mountain area topographic map;

s2, respectively constructing a disaster prediction model of each mountain area according to historical data when the debris flow disaster occurs;

s3, performing debris flow grade assessment in each mountain area according to the probability of debris flow disasters in the disaster prediction model, and mapping the assessed mountain area grade in a mountain area three-dimensional model, wherein the steps comprise:

s3.1, dividing the probability of the debris flow in each mountain area based on a disaster prediction model into: safety, hazard, relatively hazardous, and extreme hazard;

s3.2, marking the mountain area by adopting different colors in the three-dimensional model of the mountain area according to the divided mountain area;

s3.3, marking the safe mountain area with the grade divided as green, the dangerous mountain area with the grade divided as yellow, the dangerous mountain area with the grade divided as orange, and the extremely dangerous mountain area with the grade divided as red;

s4, performing protection treatment on the mountain area marked with yellow, orange and red colors in the three-dimensional mountain area model, including:

s4.1, set up a plurality of runoff flow of avoiding and cross big flood interception groove on the slope that mountain area vertical direction inclination is (30, 90 °), and slow down the impact destructive power of mud-rock flow based on the protection subsystem in the slope bottom, include:

s4.1.1, introducing the debris flow into a sandstone buffer zone, wherein the debris flow sequentially flows through a plurality of sedimentation inclined plates which are distributed in a staggered manner and used for reducing the impact force of the debris flow, and partial water is introduced into a river through a flood guide pipe;

s4.1.2, the debris flow flows through the first dam, the filter grid and the second dam in sequence to resist and filter most of silt and gravel in the debris flow;

s4.1.3, guiding the water in the debris flow into a flow guide buffer area, sequentially flowing through a plurality of buffer units for slowing down the flow speed, controlling to open an electromagnetic control valve on the drainage tube when the rainfall sensor detects that the current rainfall is greater than a preset threshold value, and guiding part of water into the river through the drainage tube;

s4.1.4, the water with the reduced flow rate enters a sedimentation tank to sediment impurities, silt and broken stones, and enters a water collecting tank to be stored;

s4.2, on the gentle slope region that mountain area vertical direction inclination is (0, 30 °), divide the module to plant a plurality of green vegetation along the slope to the direction, include:

s4.2.1, arranging a plurality of criss-cross drainage paths on the gentle slope according to the terrain of the gentle slope area;

s4.2.2, forming a plurality of planting modules among the plurality of criss-cross drainage paths;

s4.2.3, planting trees and herbaceous plants for preventing water and soil loss in all planting modules at the same height of the gentle slope along the direction of the gentle slope, and planting herbaceous plants in all planting modules at the other height of the gentle slope, namely planting the trees and the herbaceous plants in a staggered manner along the direction of the gentle slope;

s4.2.4 each of the diversion channels extends to the mountain and is communicated with the mountain river, canal, farmland, orchard or fish pond.

2. The debris flow persuasion and dispersion method according to claim 1, wherein in S2, disaster prediction models of the mountain areas are respectively constructed according to historical data when a debris flow disaster occurs;

P＝ρ_xD_xρ_yD_y+ρ₁C₁+ρ₂C₂+ρ₃M₁+ρ₄M₂+ρ₅M₃+ρ₆N₁+ρ₇N₂

wherein P is the probability of debris flow disaster, D_xFor intensity of rainfall, D_yDuration of rainfall, C₁Is a regional main vegetation species, C₂Coverage area for the main vegetation species in the region, M₁Is the main type of mountain soil or rock mass, M₂Thickness of soil or rock mass, M₃Is the rock mass or soil looseness, N₁Is the angle of inclination of the vertical direction of the mountain, N₂The vertical gully depth is formed by the horizontal inclination angle of the mountain body, namely rho_x、ρ_y、ρ₁、ρ₂、ρ₃、ρ₄、ρ₅、ρ₆And ρ₇Is a probability factor.

3. The debris flow persuasion method of claim 1, wherein the solving of the probability factors of the disaster prediction model in the S2 includes:

s2.1, normalizing historical data when the debris flow disaster occurs for a plurality of years;

s2.2, dividing the data after normalization into a training set D and a test set C according to a ratio of 5: 2;

s2.3, setting iteration times n, wherein n is more than 1000, and training a disaster prediction model on a training set D to obtain a plurality of groups of probability factors;

s2.4, evaluating the trained disaster prediction model on the test set C to obtain a plurality of groups of test errors, and selecting a probability factor with the minimum error value to carry in to obtain a disaster prediction model with the minimum error;

s2.5, randomly dividing the training set D into training sets D_trainAnd a verification set D_valid；

S2.6, in training set D_trainTraining a minimum error disaster prediction model;

s2.7 in verification set D_validTesting the model probability precision of the minimum error disaster prediction model;

and S2.8, repeating the step S2.5 to the step S2.7 until the probability precision of the model reaches a preset value.

Technical Field

The invention belongs to the technical field of debris flow treatment, and particularly relates to a debris flow dredging method.

Background

In south China, the valleys are vertical and horizontal, the two banks of the channel are usually severely weathered, the rock mass on the surface layer is broken, and after the action of heavy rainfall, earthquake and the like, the broken rock soil on the surface layer can be stripped off the mountain body, so that debris flow occurs in the channel. For example, after the Wenchuan earthquake, the mud-rock flow in the Sichuan area is more and more frequent, and the mud-rock flow causes huge loss to the local area.

The debris flow is a special flood flow carrying a large amount of debris, stones and the like, and has the characteristics of sudden outbreak, violent coming situation and strong destructive power.

The conditions for the formation of a debris flow can be divided into:

1. an abundant water source; 2. abundant loose solid matter; 3. favorable basin shape and longitudinal slope of the ditch bed. Among the factors responsible for the debris flow, hydrodynamic conditions are environmentally variable factors, and loose solid matter and watershed conditions are relatively fixed factors. Therefore, in the process of forming the debris flow, the carried debris can cause the flood flow to have strong scouring capability, erode the channel and draw in more debris, and gradually develop the scale of the debris flow. The debris flow comprises a formation area, a circulation area and a stacking area, and the debris flow prevention project is suitable for the formation area and the circulation area of the debris flow. The hydrodynamic force conditions of the formation area and the circulation area of the debris flow are controlled, and the debris flow disaster can be effectively prevented.

The existing debris flow treatment engineering mainly comprises water interception engineering, storage engineering, drainage engineering, slope protection engineering and the like so as to control the generation and harm of debris flow. The engineering such as water interception is utilized to control surface flood runoff, the hydrodynamic condition is reduced, favorable topographic conditions are needed, and the method is mainly suitable for the treatment of large debris flow ditches. The method is an effective measure for reducing the harm of the debris flow, and comprises the steps of building check houses, check dams, pools, reservoirs or swales for storing the debris flow, so that loose solid substances do not participate in the movement of the debris flow, and utilizing the swales, gullies, wastelands, lakes and marshes or building embankments outside the range of a protection area to introduce the debris flow into a bin with a large enough volume for storage, so that the debris flow is not harmful.

The main problems of the impounding project are large project amount and more using limitation conditions.

The drainage engineering is to utilize the engineering of flood drainage channel and aqueduct to drain the debris flow and control the damage of debris flow. The debris flow has strong invasion capacity and abundant solid substances, so the requirements of the anti-scouring and anti-silting capacities of the drainage groove are high.

Besides engineering measures, by planting plants such as arbors, shrubs, grasses and the like, the functions of retaining rainfall, maintaining water and soil, regulating runoff and the like are fully exerted, so that the aims of preventing and stopping debris flow or reducing the scale of debris flow and lightening the harm degree of debris flow are fulfilled. The biological measures have the characteristics of low investment, capability of improving the natural environment, long time for exerting the effect and incapability of preventing and treating the debris flow disasters in time.

To sum up, the existing debris flow has poor protection effect, and can not effectively resist and buffer or resist strong impact force and destructive force when the debris flow occurs, thereby causing serious disasters.

Disclosure of Invention

The invention aims to provide a debris flow dredging method aiming at the defects in the prior art, and aims to solve the problems that the existing debris flow has poor protection effect, and can not effectively resist and buffer or resist strong impact force and destructive force when the debris flow occurs, so that serious disasters are caused.

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

a debris flow diversion method, comprising:

s1, constructing a three-dimensional model of the mountain area according to the remote sensing technology, the regional historical hydrological data and the mountain area topographic map;

s2, respectively constructing a disaster prediction model of each mountain area according to historical data when the debris flow disaster occurs;

s3, performing debris flow grade assessment in each mountain area according to the probability of debris flow disasters in the disaster prediction model, and mapping the assessed mountain area grade in a mountain area three-dimensional model, wherein the steps comprise:

s3.1, dividing the probability of the debris flow in each mountain area based on a disaster prediction model into: safety, hazard, relatively hazardous, and extreme hazard;

s3.2, marking the mountain area by adopting different colors in the three-dimensional model of the mountain area according to the divided mountain area;

s3.3, marking the safe mountain area with the grade divided as green, the dangerous mountain area with the grade divided as yellow, the dangerous mountain area with the grade divided as orange, and the extremely dangerous mountain area with the grade divided as red;

s4, performing protection treatment on the mountain area marked with yellow, orange and red colors in the three-dimensional mountain area model, including:

s4.1, set up a plurality of runoff flow of avoiding and cross big flood interception groove on the slope that mountain area vertical direction inclination is (30, 90 °), and slow down the impact destructive power of mud-rock flow based on the protection subsystem in the slope bottom, include:

s4.1.1, introducing the debris flow into a sandstone buffer zone, wherein the debris flow sequentially flows through a plurality of sedimentation inclined plates which are distributed in a staggered manner and used for reducing the impact force of the debris flow, and partial water is introduced into a river through a flood guide pipe;

s4.1.2, the debris flow flows through the first dam, the filter grid and the second dam in sequence to resist and filter most of silt and gravel in the debris flow;

s4.1.3, guiding the water in the debris flow into a flow guide buffer area, sequentially flowing through a plurality of buffer units for slowing down the flow speed, controlling to open an electromagnetic control valve on the drainage tube when the rainfall sensor detects that the current rainfall is greater than a preset threshold value, and guiding part of water into the river through the drainage tube;

s4.1.4, the water with the reduced flow rate enters a sedimentation tank to sediment impurities, silt and broken stones, and enters a water collecting tank to be stored;

s4.2, on the gentle slope region that mountain area vertical direction inclination is (0, 30 °), divide the module to plant a plurality of green vegetation along the slope to the direction, include:

s4.2.1, arranging a plurality of criss-cross drainage paths on the gentle slope according to the terrain of the gentle slope area;

s4.2.2, forming a plurality of planting modules among the plurality of criss-cross drainage paths;

s4.2.3, planting trees and herbaceous plants for preventing water and soil loss in all planting modules at the same height of the gentle slope along the direction of the gentle slope, and planting herbaceous plants in all planting modules at the other height of the gentle slope, namely planting the trees and the herbaceous plants in a staggered manner along the direction of the gentle slope;

s4.2.4 each of the diversion channels extends to the mountain and is communicated with the mountain river, canal, farmland, orchard or fish pond.

Preferably, in S2, according to historical data of the debris flow disaster, a disaster prediction model of each mountain area is respectively constructed as;

P＝ρ_xD_xρ_yD_y+ρ₁C₁+ρ₂C₂+ρ₃M₁+ρ₄M₂+ρ₅M₃+ρ₆N₁+ρ₇N₂

wherein P is the probability of debris flow disaster, D_xFor intensity of rainfall, D_yDuration of rainfall, C₁Is a regional main vegetation species, C₂Coverage area for the main vegetation species in the region, M₁Is mountain soilOr main type of rock mass, M₂Thickness of soil or rock mass, M₃Is the rock mass or soil looseness, N₁Is the angle of inclination of the vertical direction of the mountain, N₂The vertical gully depth is formed by the horizontal inclination angle of the mountain body, namely rho_x、ρ_y、ρ₁、ρ₂、ρ₃、ρ₄、ρ₅、ρ₆And ρ₇Is a probability factor.

Preferably, the solving of the probability factor of the disaster prediction model in S2 includes:

s2.1, normalizing historical data when the debris flow disaster occurs for a plurality of years;

s2.2, dividing the data after normalization into a training set D and a test set C according to a ratio of 5: 2;

s2.3, setting iteration times n, wherein n is more than 1000, and training a disaster prediction model on a training set D to obtain a plurality of groups of probability factors;

s2.4, evaluating the trained disaster prediction model on the test set C to obtain a plurality of groups of test errors, and selecting a probability factor with the minimum error value to carry in to obtain a disaster prediction model with the minimum error;

s2.5, randomly dividing the training set D into training sets D_trainAnd a verification set D_valid；

S2.6, in training set D_trainTraining a minimum error disaster prediction model;

s2.7 in verification set D_validTesting the model probability precision of the minimum error disaster prediction model;

and S2.8, repeating the step S2.5 to the step S2.7 until the probability precision of the model reaches a preset value.

The debris flow dredging method provided by the invention has the following beneficial effects:

according to the method, according to color discrimination of debris flow disaster probability in a three-dimensional model of a mountain area, multi-level protection treatment is carried out on the mountain area where debris flow disasters easily occur, and the mountain area where debris flow disasters easily occur is subjected to differential protection of a steep slope and a gentle slope, so that the impact force and destructive force of debris flow on the steep slope are effectively reduced, and on the premise of reducing water and soil loss of the gentle slope, water flow on the gentle slope is converged to the underground of the mountain in a centralized manner, and multi-level utilization of a water body is carried out.

Drawings

Fig. 1 is a flow chart of a debris flow dredging method.

Fig. 2 is a structural diagram of a protection subsystem of the debris flow dredging method.

FIG. 3 is a diagram of a sand buffer zone structure in a debris flow diversion method.

Fig. 4 is a structure diagram of a settling inclined plate of the debris flow dredging method.

Fig. 5 is a structural diagram of a buffering unit of the debris flow dredging method.

Fig. 6 is a schematic view of gentle slope dredging by the debris flow dredging method.

Wherein, 1, mountain slope; 2. a flood interception groove; 3. a sandstone buffer zone; 4. a streaming buffer area; 5. a sedimentation tank; 6. a water collecting tank; 7. a sedimentation sloping plate; 8. a flood guiding pipe; 9. a first dam; 10. a second dam; 11. a drainage tube; 12. filtering the grating; 13. a buffer unit; 14. a settling chute; 15. buffering the stairs; 16. a rectangular drainage groove; 17. an electromagnetic control valve; 18. a drainage path; 19. and (6) gentle slope.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.

According to an embodiment of the present application, referring to fig. 1 to 6, the debris flow dredging method of the present application includes:

s1, constructing a three-dimensional model of the mountain area according to the remote sensing technology, the regional historical hydrological data and the mountain area topographic map;

s2, respectively constructing a disaster prediction model of each mountain area according to historical data when the debris flow disaster occurs;

s3, performing debris flow grade assessment in each mountain area according to the probability of debris flow disasters in the disaster prediction model, and mapping the assessed mountain area grade in a mountain area three-dimensional model, wherein the steps comprise:

and S4, performing protective treatment on the mountain areas marked with yellow, orange and red colors in the three-dimensional mountain area model.

The above steps will be described in detail below according to one embodiment of the present application.

S1, constructing a three-dimensional model of the mountain area according to the remote sensing technology, the regional historical hydrological data and the mountain area topographic map;

the remote sensing technology can be video image information acquired by the unmanned aerial vehicle, and can also be image information scanned by the radar.

And converting the image information, the video information and the mountain area topographic map into image information which can be identified by 3DS MAX 3DS MAX, inputting the area historical hydrological data as model parameters, and constructing a mountain area three-dimensional model based on the 3DS MAX 3DS MAX.

Step S2, respectively constructing a disaster prediction model of each mountain area according to historical data when the debris flow disaster occurs:

P＝ρ_xD_xρ_yD_y+ρ₁C₁+ρ₂C₂+ρ₃M₁+ρ₄M₂+ρ₅M₃+ρ₆N₁+ρ₇N₂

wherein P is the probability of debris flow disaster, D_xFor intensity of rainfall, D_yDuration of rainfall, C₁Is a regional main vegetation species, C₂Coverage area for the main vegetation species in the region, M₁Is the main type of mountain soil or rock mass, M₂Thickness of soil or rock mass, M₃Is the rock mass or soil looseness, N₁Is the angle of inclination of the vertical direction of the mountain, N₂The vertical gully depth is formed by the horizontal inclination angle of the mountain body, namely rho_x、ρ_y、ρ₁、ρ₂、ρ₃、ρ₄、ρ₅、ρ₆And ρ₇Is a probability factor.

The construction of the disaster prediction model and the determination of the parameters such as the probability factor specifically comprise the following steps:

s2.1, normalizing historical data of the mud-rock flow disasters which occur for a plurality of years, including D_xIntensity of rainfall, D_yDuration of rainfall, C₁Regional main vegetation species, C₂Area covered by main vegetation type in the area, M₁Main type of mountain soil or rock mass, M₂Thickness of soil or rock mass, M₃Bulk of rock mass or soil, N₁Angle of inclination of mountain in vertical direction, N₂The angle of inclination of the horizontal direction of the mountain body is the depth of the formed longitudinal ravines.

S2.2, dividing the data after normalization into a training set D and a test set C according to a ratio of 5: 2;

the division ratio of the training set D and the test set C is not fixed, and can be changed according to actual conditions.

S2.3, setting iteration times n, wherein n is more than 1000, and training a disaster prediction model on a training set D to obtain a plurality of groups of probability factors;

the iteration number n can be determined according to actual conditions, and is used for obtaining multiple groups of probability factors.

S2.4, evaluating the trained disaster prediction model on the test set C to obtain a plurality of groups of test errors, and selecting a probability factor with the minimum error value to carry in to obtain a disaster prediction model with the minimum error;

because the probability factor with the minimum error value is introduced, and the test data is observed in advance, the parameters are set around better fitting test data, and the probability factor with the minimum error value is only possibly an optimal estimation of the generalization error. The test data is used for multiple times, and the principle that the test data is only used for evaluating the generalization performance of the optimal function is violated, so the model cannot be adopted for verifying the generalization performance of the model.

Therefore, the following training set is adopted for classification verification:

s2.5, randomly dividing the training set D into training sets D_trainAnd a verification set D_valid；

Step S2.6, in training set D_trainTraining a minimum error disaster prediction model;

step S2.7, in the verification set D_validTesting the model probability precision of the minimum error disaster prediction model;

and S2.8, repeating the step S2.5 to the step S2.7 until the probability precision of the model reaches a preset value.

To solve the problem, a verification set D is separately divided from the training set_validThe data set is a training set composed of a training set and a testing set, and a testing set is composed of a testing set and a training set.

Step S3, according to the probability of debris flow disasters in the disaster prediction model, the debris flow grade of each mountain area is evaluated, and the grade of the evaluated mountain area is mapped in a three-dimensional model of the mountain area, and the method comprises the following steps:

dividing the probability of the debris flow in each mountain area based on a disaster prediction model into: safety, hazard, relatively hazardous, and extreme hazard;

mapping the divided mountain area into a mountain area three-dimensional model, and marking the mountain area by adopting different colors in the mountain area three-dimensional model;

the mountain areas classified as safe are marked as green, the mountain areas classified as dangerous are marked as yellow, the mountain areas classified as more dangerous are marked as orange, and the mountain areas classified as extremely dangerous are marked as red.

The probability of the debris flow disasters in each mountain area, which is obtained by predicting the disaster prediction model, is mapped into the constructed three-dimensional model of the mountain area, so that client monitoring personnel can visually observe the probability of the debris flow disasters in each mountain area.

S4, performing protection treatment on the mountain area marked with yellow, orange and red colors in the three-dimensional model of the mountain area, wherein the protection treatment comprises the following steps:

s4.1, set up a plurality of runoff flow of avoiding and cross greatly on the slope that mountain area vertical direction inclination is (30, 90 °) and cut a flood groove 2 to at the slope bottom based on the impact destructive power that the protection subsystem slowed down the mud-rock flow:

wherein, the protection subsystem for according to the mountain area grade in the three-dimensional model of mountain area, namely the probability grade that mountain area takes place debris flow calamity, construct mountain area protection and dredge structure, include:

a plurality of flood interception grooves 2 distributed on a mountain slope 1, and a sand buffer zone 3, a diversion buffer zone 4, a sedimentation tank 5 and a water collection tank 6 which are arranged at the bottom of the mountain and are sequentially communicated.

The flood interception groove 2 can be used for accommodating partial water volume, and avoids huge destructive power caused by one-time inflow of excessive water volume into the mountains.

The sand buffer zone 3 is an area directly contacting with the debris flow and has the function of buffering the huge impact force caused by the debris flow and reducing the damage of equipment and infrastructure.

A plurality of sedimentation inclined plates 7 are installed in the sandstone buffer zone 3 in a staggered manner, the side surfaces of the sedimentation inclined plates 7 are triangular, the bottommost ends of the sedimentation inclined plates 7 are arranged close to the slope, and an acute angle alpha formed by the sedimentation inclined plates 7 and the horizontal plane of the sandstone buffer zone 3 is 45-70 degrees; the sedimentation inclined top surface is transversely provided with a plurality of sedimentation chutes 14, the sedimentation chutes 14 are internally arc-shaped, the central angle of the arc is 120 degrees, and the radius of the circle corresponding to the central angle is 10 cm.

That is, when the debris flow flows through a single sedimentation sloping plate 7, the sedimentation sloping plate 7 has a certain gradient, so that the effect of slowing down the impact force of the debris flow is achieved, and the sedimentation chutes 14 on the sedimentation sloping plate further accelerate the sedimentation of the debris flow and reduce the impact force of the debris flow.

Besides, the sedimentation inclined plates 7 are distributed in a staggered mode, so that the impact force of the debris flow can be dispersed, namely, the impact force is dispersed, the overlarge impact force is avoided, and meanwhile, the infrastructure is protected.

At the both sides limit end of grit buffer zone 3, all install a plurality of flood ducts 8, flood duct 8 entrance is equipped with the filter screen, and flood duct 8 can derive partial moisture in the mud-rock flow, reduces the weight of mud-rock flow, reduces the impact force of mud-rock flow from the side, has also reduced the impact pressure of other facilities.

A first dam 9 and a second dam 10 are arranged between the sandstone buffer zone 3 and the diversion buffer zone 4; a plurality of filtering grids 12 are arranged between the first dam 9 and the second dam 10; a plurality of flood discharge holes are formed in the first dam 9 and the second dam 10, and overflow ports are formed in the tops of the first dam 9 and the second dam 10.

According to the invention, the filtering grid 12 is arranged at the rear end of the first dam 9, the filtering device is arranged at the front end of the first dam 9 in the traditional technology, so that when debris flow occurs, the filtering device at the front end is directly contacted with the debris flow, and the damage of the filtering device is easily caused.

In addition to this, a second dam 10 is provided to provide a secondary barrier to the debris flow, i.e. to block the filtered silt between the first and second dams 9, 10, the space between the first and second dams 9, 10 may be large enough to accommodate enough silt (where it is sufficient, not a hundred percent interception).

And the flow guide buffer area 4 is used for slowing down the water flow impact force of the debris flow.

The diversion buffer area 4 comprises a plurality of buffer units 13 which are distributed at equal intervals, each buffer unit 13 comprises two buffer steps 15, and each buffer step 15 is in a trapezoidal shape in a side view; a rectangular drainage groove 16 is formed between the two buffer steps 15, the bottom of the drainage groove is communicated with the drainage tube 11, and an electromagnetic control valve 17 is installed on the drainage tube 11.

Water in the debris flow enters the flow guide buffer area 4 and sequentially flows through the buffer ladder 15 and the rectangular drainage groove 16 between the buffer ladders 15, the buffer ladder 15 has a certain gradient and can slow down the water flow speed, the slowed water flow enters the rectangular drainage groove 16, and the rectangular drainage groove 16 can contain partial water volume to further slow down the water flow speed; the electromagnetic control valve 17 is opened, so that part of water in the rectangular drainage groove 16 can be guided out, the water flow quantity is further reduced, and the water flow impact force is further relieved.

Wherein the derived water flow can be directed into rivers, fields and canals.

The water content of the debris flow passing through the diversion buffer area 4 tends to be gentle, and the debris flow is guided into the sedimentation tank 5 to precipitate silt and impurities and finally guided into the water collecting tank 6.

The protection method comprises the following steps:

s4.1.1, the debris flow enters a sand and stone buffer zone 3, flows through a plurality of sedimentation inclined plates 7 which are distributed in a staggered mode, the impact force of the debris flow is relieved, and partial water is guided into a river through a flood guiding pipe 8;

s4.1.2, the debris flow flows through the first dam 9, the filter grid 12 and the second dam 10 in sequence to resist and filter most of silt and gravel in the debris flow;

s4.1.3, the water in the debris flow flows into the diversion buffer area 4 and flows through a plurality of buffer units 13 for slowing down the flow speed in sequence, when the rainfall sensor detects that the current rainfall is larger than the preset threshold value, the electromagnetic control valve 17 on the drainage tube 11 is controlled to be opened, and part of water is guided into the river through the drainage tube 11;

in step S4.1.3, a riverbed resistance function M is constructed according to the vertical height difference of the adjacent buffer steps 15 and the hydraulic slope of the diversion buffer area 4:

wherein, β is an acute angle formed by the buffer step 15 relative to the plane of the flow guide buffer 4; h is the maximum water depth of the rectangular drainage groove 16; Δ h is the vertical height difference of two adjacent buffer steps 15; i is hydraulic slope;

setting the maximum buffer resistance of the diversion buffer area 4 to the debris flow as a target function Mmax, namely calculating a maximum riverbed resistance function Mmax:

according to multiple groups of experiments and simulation calculation, when the riverbed resistance function Mmax is in the range of 0.6, 1), the flow guide buffer area 4 has the largest buffering resistance to debris flow, and the vertical height difference of two adjacent buffering steps 15 of the flow guide buffer area 4, the maximum water depth H of the rectangular drainage groove 16 and the acute angle beta formed by the buffering steps 15 relative to the plane where the flow guide buffer area 4 is located are designed according to the largest buffering resistance.

S4.1.4, the water with the reduced flow rate enters the sedimentation tank 5 to sediment impurities, silt and broken stones, and enters the water collecting tank 6 to be stored.

And S4.2, planting a plurality of green vegetation in a module mode along the slope direction in a gentle slope 19 area with an inclination angle of (0 degrees and 30 degrees) in the vertical direction of the mountain area.

S4.2 on the 19 regions of gentle slope that mountain area vertical direction inclination is (0, 30 °), divide the module to plant a plurality of green vegetation along the slope direction, include:

s4.2.1, arranging a plurality of criss-cross drainage paths 18 on the gentle slope 19 according to the regional terrain of the gentle slope 19;

s4.2.2, forming a plurality of planting modules among the plurality of criss-cross drainage paths 18;

s4.2.3, planting trees for preventing water and soil loss in all planting modules at the same height of the gentle slope 19 along the direction of the gentle slope 19, and planting herbaceous plants in all planting modules at the other height of the gentle slope 19, namely planting the trees and the herbaceous plants in a staggered manner along the direction of the gentle slope 19;

s4.2.4 each diversion path extends to the mountain and is communicated with the mountain river, canal, farmland, orchard or fish pond.

The dredging method of the invention carries out the bidirectional management of the steep slope and the gentle slope 19, and fully utilizes water resources while dredging the flood.

According to the method, when the gentle slope 19 area of the mountain is formed, the gentle slope 19 is divided into areas, the traditional method is to directly plant tree herbs on the gentle slope 19 without carrying out module division, and the defects that when the rainfall is too large, water flow cannot be guided to the mountain in time, water puddles are formed in partial areas by rainwater, and serious debris flow disasters are caused are overcome.

A plurality of flow guide paths are arranged on the gentle slope 19, each flow guide path leads to the underground, rainwater can be effectively guided out, and water puddles cannot be formed. And planting tree vegetation in the area module formed among the guide channel forces.

Specifically, along the direction of the gentle slope 19, the planting modules at the same height of the gentle slope 19 are planted with the tree plants for preventing water and soil loss, and the planting modules at the other height of the gentle slope 19 are planted with the herb plants, namely, along the direction of the gentle slope 19, the tree plants and the herb plants are planted in a staggered mode.

The trees and the herbaceous plants are planted in a staggered mode, the tree planting method has the advantages that the heights of the trees and the herbaceous plants are different, requirements for sunlight are different, the trees and the herbaceous plants are planted in a staggered mode at intervals, water and soil loss is avoided, and the variety characteristics between the trees and the herbaceous plants are also greatly utilized.

According to the method, according to color discrimination of debris flow disaster probability in a three-dimensional model of a mountain area, multi-level protection treatment is carried out on the mountain area where debris flow disasters easily occur, and the mountain area where debris flow disasters easily occur is subjected to differential protection of a steep slope and a gentle slope 19, so that the impact force and destructive force of debris flow on the steep slope are effectively reduced, and on the premise of reducing water and soil loss of the gentle slope 19, water flow on the gentle slope 19 is converged to the mountain in a centralized manner, and multi-level utilization of a water body is carried out.

While the embodiments of the invention have been described in detail in connection with the accompanying drawings, it is not intended to limit the scope of the invention. Various modifications and changes may be made by those skilled in the art without inventive step within the scope of the appended claims.