Rock-soil-biology synergistic energy dissipation system and test method for collapsing and slipping mass material source control type debris flow

Abstract

The invention provides a rock-soil-biological synergistic energy dissipation system and a test method for collapsing and slipping mass source control type debris flow, and the test method comprises the following steps: step 1, sampling on site in a drainage basin, and determining the maximum particle size, the minimum particle size and the average particle size of particles in the drainage basin; 2, selecting a proper filter screen based on particle size distribution; and 3, collecting the size of the channel in the drainage basin, and designing the size of the configuration main body. And 4, determining dominant species in the drainage basin, and performing ecological design in combination with the configuration main body. And 5, carrying out a small water tank model test, and calculating the debris flow energy reduction rate of the configuration technology and method. According to the rock-soil-biology collaborative energy dissipation system for the collapsing and slipping mass material source control type debris flow, solid particles in the debris flow body are fully utilized to form a natural sediment storage dam, the energy dissipation effect on the debris flow can be achieved, meanwhile, ecological materials and various plants are arranged for blocking, the diversity of ecological systems in a drainage basin is improved, and the ecological system utilization rate is increased. And comprehensive treatment of the debris flow is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of geological disaster reduction, and in particular relates to a rock-soil-biological synergistic energy dissipation system and a test method for landslide source-controlled debris flows. Background Art

[0002] Debris flows are a typical occurrence in small mountainous watersheds. Among the three key factors contributing to their formation, the source of loose solids is a crucial factor. Current regulations and research categorize debris flow basins into three types based on their source: transport-controlled (derived from sediment replenishment), loose solids-controlled (derived from bedrock weathering), and landslide-controlled (derived from landslide and landslide deposits). Compared to the first two types, debris flows in landslide-controlled basins are characterized by high rock content, sudden onset, multi-point clustering, extreme destructiveness, and a cascading disaster effect. These flows not only lead to more frequent and larger debris flows, but also carry large amounts of landslide material, blocking and raising river channels, forming dams, and causing siltation and flooding. These flows pose a serious threat to the lives and property of residents in mountainous areas, disrupt national infrastructure and the safe operation of hydropower projects, and pose significant challenges to debris flow prevention and control in mountainous areas.

[0003] Currently, debris flow prevention and control measures primarily rely on geotechnical measures, forming a "stabilization, interception, drainage, and stop" disaster management system that effectively reduces debris flow, weakens energy, intercepts sand and gravel, and drains soil and water. While geotechnical measures can quickly achieve disaster reduction results, they suffer from low durability, high costs, and environmental impacts, failing to consider their impact on the ecological environment of debris flow basins. Regarding biological measures, while plants are resilient and economical, their long growth cycles make it difficult to ensure timely disaster reduction. Combining geotechnical and biological measures is a trend in debris flow management in mountainous areas, particularly in debris flow basins controlled by landslide sources. The development of geotechnical-biological synergistic energy dissipation configuration technology will not only enhance my country's debris flow disaster prevention capabilities but also provide scientific support for the development of a safer and more beautiful China. Summary of the Invention

[0004] The purpose of this invention is to provide a geotechnical-biological synergistic energy dissipation system and experimental method for landslide-source-controlled debris flows. This system utilizes unstable landslides within the basin as raw material resources to construct a primary sand dam. Simultaneously, a filter screen is used to intercept landslide particles, enhancing the dam's internal efficiency and optimizing the energy dissipation of traditional sand dams. Based on the size of the primary sand dam, an ecological sand dam is installed at its outlet for secondary energy dissipation.

[0005] In order to achieve the above technical features, the purpose of the present invention is achieved as follows: a geotechnical-biological synergistic energy dissipation system for landslide source-controlled debris flows, wherein the energy dissipation system is arranged in the area connected to the debris flow in the basin, and the energy dissipation system is a multi-dimensional protection system consisting of a W-type filtration system, a main dam, a branch dam and a plant dam; The main dam is arranged inside the upper opening of the W-shaped filtration system, and the sub-dams are arranged between adjacent main dams; The plant dam is arranged inside the lower opening of the W-shaped filtration system; The W-shaped filtering system is provided with a nozzle device for collecting water and a sprinkler device for irrigation.

[0006] Preferably, the W-shaped filtration system includes a plurality of impact columns arranged in a W shape, adjacent impact columns located on the inner side are fixedly connected by an inner filter fence, and adjacent impact columns located on the outer side are fixedly connected by an outer filter fence.

[0007] Preferably, the main dam is an arc-shaped structure composed of a gabion mesh and landslide bodies in the watershed; the root of the main dam is fixedly connected to the impact column, the size of the main dam is half the opening size of the W-type filtration system, and the angle formed with it is 45°, and the cross section is an arc; The landslide bodies in the basin are blocks with a particle size greater than 40 mm.

[0008] Preferably, the sub-dam is half the size of the main dam, and the angle formed with the W-shaped filtering system is 60°, and the cut surface is a straight edge with a cut angle greater than 60°.

[0009] Preferably, the plant dam is a sand retaining dam formed by planting shrubs and trees on an ecological substrate; The shrubs and trees are arranged in a staggered, curved arc arrangement; There are two rows of plant dams, and they are planted in two back-to-back fan rings. The width of the ring is the same as the diameter of the impact column. The center of the upper fan ring is the centroid of the lower fan ring; the center of the lower fan ring is the centroid of the upper fan ring. The ecological base material of the entire plant dam base is vegetation concrete material.

[0010] Preferably, the nozzle device comprises a water collection pipe, which is a water collection pipe network formed by an inner filter fence and an outer filter fence; A water inlet is provided on the water collecting pipe at the bottom, and the water collecting pipe is connected with the upper hollow water storage column. The upper hollow water storage column is the upper structure of the impact column, and the bottom of the upper hollow water storage column is the lower solid impact column.

[0011] Preferably, the sprinkler device includes a sprinkler device body, a sprinkler device connection port is provided at the bottom of the sprinkler device body, the sprinkler device connection port is connected to the upper hollow water storage column, a plurality of water spray holes are provided on the outside of the sprinkler device body, and a sprinkler back-pressure pumping device is provided on the top of the sprinkler device body.

[0012] Another aspect of the present invention provides a test method for geotechnical-biological synergistic energy dissipation of debris flows controlled by landslide sources. The method is implemented using the geotechnical-biological synergistic energy dissipation system and includes the following steps: Step 1: Conduct on-site sampling within the watershed to determine the particle size distribution within the watershed; Step 2: Select the appropriate filter based on particle size distribution; Step 3: Collect basic information about the watershed and design the size of the energy dissipation system; Step 4: Identify the dominant species in the watershed and conduct ecological design in conjunction with the energy dissipation system; Step 5: Conduct a small flume model test to calculate the energy reduction rate of the energy dissipation system on debris flow.

[0013] Preferably, the on-site sampling in step 1 includes soil samples from the source area, circulation area and upper and lower layers of the accumulation area in the watershed; The provenance area provides material conditions for the formation of debris flows; The circulation area is used to change the movement characteristics of the debris flow; The accumulation area is used to provide a place for debris flow to stop and accumulate; The particle size distribution includes maximum particle size, minimum particle size, and average particle size; Wherein, in said step 2, the filter size P for: P =( P max + P min ) / 2; Where, P max is the maximum particle size in the basin, P min is the minimum particle size in the watershed; Among them, the filter size of the outer filter fence is set to P min ; In step 3, the basic information of the basin includes: hydrological conditions, climatic conditions, topography, geological environment, human conditions and disaster conditions; The hydrological conditions include river length, river direction, tributary shape, number of tributaries, river network density, river drop, and canyon distribution; The topography includes the type of terrain, relief, inclination, extreme value and altitude. In the step 3, when designing the size of the energy dissipation system, the opening angle θ of the W-type filter system is related to the peak flow rate of the debris flow with a frequency of P. Q C is a functional relationship, where Q C Determined by the storm flood flow corresponding to the frequency P; Peak flow of debris flow Q C The calculation formula is: ; in, is the peak flow rate of debris flow with frequency P, in m³ / s; is the design flow rate of rainstorm flood with frequency P, in m³ / s; is the debris flow sediment correction coefficient, where ; is the bulk density of debris flow, in t / m³; is the specific gravity of clean water, in t / m³, with a value of 1.0; is the specific gravity of solid matter in debris flow, unit is t / m³; is the debris flow blocking coefficient; The impact column adopts a variable cross-section design, wherein the main impact column cross-sectional area A at the axis is m satisfy: ; in, is the peak value of debris flow impact load; is the safety factor, take 1.5-2.0; The yield strength of the impact column material is the main impact column. The bending section strength of the main impact column should be 1.2-1.5 times that of the other impact columns, and its burial depth must meet the overturning stability requirements. The height H1 of the lower solid impact column satisfies: ; where h max is the maximum depth of debris flow in the basin; Δh is the safety overheight, which is 0.3-0.5m; the height of the upper hollow water column H 2 Determined based on the demand for rainwater storage.

[0014] Preferably, the energy reduction rate of the debris flow by the energy dissipation system in step 5 is: ; in, W is the debris flow energy reduction rate in the basin;C is the debris flow energy experimental coefficient; is the volume fraction of solid particles; is the average particle size of solid particles, in m; is the bulk density of solid particles, in kN / m³; is the solid phase particle velocity, in m / s; is the bulk density of the liquid phase, in kN / m³; is the liquid phase flow rate, in m / s; is the angle between flow direction and flow velocity.

[0015] The present invention has the following beneficial effects: The present invention provides a geotechnical-ecological synergistic energy dissipation system for debris flows controlled by landslide sources. The basic dimensions of the configuration are determined based on the hydrological conditions, climatic conditions, topography, geological environment, human conditions and disaster conditions in the basin. The internal filter screen of the configuration is designed in combination with the particle size distribution in the basin to achieve the effect of energy dissipation inside the main body of the sand dam. Based on the outlet size of the sand dam, an ecological retaining dam is designed to achieve a secondary energy dissipation effect. Compared with previous technologies, in addition to blocking the solid particles of the debris flow, more importantly, the present invention can carry out autonomous energy dissipation when the debris flow moves into the interior of the configuration, which greatly improves the disaster reduction effect of the sand dam for debris flows controlled by landslide sources. At the same time, the ecological sand dam set up by the present invention improves the ecological stability in the debris flow basin and realizes the comprehensive prevention and control of debris flow disasters. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below with reference to the accompanying drawings and examples.

[0017] Figure 1 This is a flow chart of a rock-soil-ecological synergistic energy dissipation system method for landslide source-controlled debris flows implemented by the present invention.

[0018] Figure 2 A three-dimensional diagram of the system of the present invention.

[0019] Figure 3 A top view of the system of the present invention.

[0020] Figure 4 It is a three-dimensional diagram of the sprinkler irrigation device of the present invention.

[0021] Figure 5 This is a three-dimensional diagram of the test conducted for the small water tank model test example of the present invention.

[0022] Figure 6 This is a front view of the test conducted on the small water tank model test example of the present invention.

[0023] In the figure: impact column 1, outer filter fence 2, sub-dam 3, main dam 4, inner filter fence 5, water collecting pipe 6, sprinkler 7, lower solid impact column 8, upper hollow water storage column 9, plant dam 10, water inlet 11, spray hole 12, sprinkler connection port 13, sprinkler back pressure pumping device 14, sprinkler main body 15, accumulation area 16, circulation area 17, pore water pressure sensor 18, impact force sensor 19, material source area 20, material source 1 21, material source 2 22, material source 3 23, energy dissipation system 24, W-type filtration system 25. DETAILED DESCRIPTION

[0024] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0025] Example 1: Reference Figure 1-6 A geotechnical-biological synergistic energy dissipation system for debris flows controlled by landslide sources. The energy dissipation system 24 is arranged in a communication area with the debris flow in the basin. The energy dissipation system 24 is a multi-dimensional protection system consisting of a W-type filtration system 25, a main dam 4, a sub-dam 3, and a plant dam 10. The main dam 4 is arranged inside the upper opening of the W-type filtration system 25, and the sub-dam 3 is arranged between adjacent main dams 4. The plant dam 10 is arranged inside the lower opening of the W-type filtration system 25. The W-type filtration system 25 is provided with a nozzle device for collecting water and a sprinkler device 7 for irrigation. By adopting the above-mentioned energy dissipation system, the solid phase particles in the debris flow are fully utilized to form a natural sediment barrier, which can achieve the effect of dissipating energy for the debris flow. At the same time, the provision of ecological materials and a variety of plants to block the flow improves the diversity of the ecosystem in the basin and achieves comprehensive control of the debris flow.

[0026] Furthermore, the W-shaped filtration system 25 includes a plurality of impact columns 1 arranged in a W-shape. Adjacent impact columns 1 located on the inner side are fixedly connected by an inner filter fence 5, and adjacent impact columns 1 located on the outer side are fixedly connected by an outer filter fence 2. The W-shaped filtration system 25 can divert the debris flow from the center after it occurs, thereby achieving the effect of initial diversion and energy dissipation.

[0027] Furthermore, the main dam 4 is an arc-shaped structure composed of gabions and landslides within the watershed. The base of the main dam 4 is fixedly connected to the impact column 1. The main dam 4 is half the size of the opening of the W-shaped filter system 25, forming a 45° angle with it and possessing an arc-shaped cross-section. This main dam 4 can be used to block debris flows after diversion, thereby achieving a secondary barrier effect.

[0028] Furthermore, the landslide body in the watershed is a block with a particle size greater than 40 mm. The landslide body in the watershed can better adapt to the corresponding environmental requirements of the landslide area and ensure the energy dissipation effect.

[0029] Furthermore, the sub-dam 3 is half the size of the main dam 4, forming a 60° angle with the W-shaped filter system 25, and has a straight cut surface with an angle greater than 60°. The sub-dam 3 can be used to secondary divert and dissipate energy from debris flows entering the main dam 4.

[0030] Furthermore, the plant dam 10 is a sand-retention dam formed by planting shrubs and trees on an ecological substrate; the shrubs and trees are arranged in a staggered curved arc. The plant dam 10 can dissipate the energy of debris flows passing through the inner filter fence 5, while also achieving a greening effect.

[0031] Furthermore, the plant dam 10 has two rows of plants arranged in two back-to-back fan rings. The ring width is the same as the diameter of the impact column 1. The center of the upper fan ring is the centroid of the lower fan ring, and the center of the lower fan ring is the centroid of the upper fan ring. The ecological base material of the entire plant dam 10 is a vegetation concrete material. This arc-shaped arrangement effectively disperses the impact force.

[0032] Furthermore, the nozzle assembly includes a water collection pipe 6, which is a water collection network formed by the inner filter fence 5 and the outer filter fence 2. A water inlet 11 is provided on the bottom of the water collection pipe 6. The water collection pipe 6 is connected to the upper hollow water storage column 9, which is the upper structure of the impact column 1. The bottom of the upper hollow water storage column 9 is the lower solid impact column 8. The nozzle assembly can be used to collect water and store it in the upper hollow water storage column 9 for subsequent irrigation.

[0033] Furthermore, the sprinkler irrigation device 7 includes a sprinkler irrigation device body 15, a sprinkler irrigation device connection port 13 is provided at the bottom of the sprinkler irrigation device body 15, and the sprinkler irrigation device connection port 13 is connected to the upper hollow water storage column 9. The sprinkler irrigation device body 15 is provided with a plurality of water spray holes 12 on the outside, and a sprinkler irrigation back-pressure pumping device 14 is provided on the top of the sprinkler irrigation device body 15. The sprinkler irrigation device 7 facilitates the subsequent spraying of water stored in the upper hollow water storage column 9, thereby achieving the purpose of irrigation.

[0034] Example 2: Landslide source-controlled debris flow outbreaks carry a large amount of landslide source, which is extremely destructive and has a strong destructive effect. The current mainstream prevention and control measures are mainly geotechnical engineering. Although it can quickly achieve disaster reduction effects, it will damage the ecological environment and resources cannot be fully utilized. Based on the concept of multi-dimensional collaborative governance, this invention innovatively constructs a geotechnical-ecological collaborative energy dissipation system and test method for landslide source-controlled debris flow, such as Figure 1 1 is a flow chart of a rock-soil-ecological synergistic energy dissipation system and method for landslide source-controlled debris flow according to an embodiment of the present invention.

[0035] A test method for geotechnical-biological synergistic energy dissipation of landslide source-controlled debris flow, comprising the following steps: P101. Conduct on-site sampling within the watershed to determine the particle size distribution within the watershed: In this embodiment, the basin is rationally divided into the following categories: source area, circulation area, and accumulation area according to hydrological conditions, climatic conditions, topography, geological environment, human conditions, and disaster conditions; On-site field sampling was conducted in three areas of the watershed to determine the maximum, minimum and average particle sizes and confirm the particle size distribution.

[0036] P102. Select the appropriate filter based on particle size distribution: In this example, the landslide body in the watershed is a block with a particle size greater than 40 mm. The size of the inner filter screen is determined based on the particle size distribution obtained by on-site sampling. P for:( P max + P min ) / 2, where P max is the maximum particle size in the basin, P min is the minimum particle size in the watershed. The outer filter size is set to P min Its main purpose is to block solid particles and filter slurry, thereby forming a natural retaining dam outside the W-type filtration system 25, and cooperating with the main dam and sub-dam to play an energy dissipation role.

[0037] P103. Collect basic information about the watershed and design the dimensions of the main configuration: In this embodiment, the Figure 2-4 The energy dissipation system 24 shown is arranged in the area connected to the debris flow in the basin, and its structure includes a multi-dimensional protection system consisting of a W-shaped filtration system 25, a main dam, branch dams and plant dams.

[0038] The W-shaped filtering system 25 in this example adopts a cooperative structure of impact columns 1, outer filter fence 2 and inner filter fence 5, specifically including: impact columns 1 arranged in a W shape along the direction of the debris flow, and inner filter fence 5 and outer filter fence 2 arranged inside the impact columns 1. The expansion angle θ of the W-shaped opening is related to the peak flow rate of the debris flow with a frequency of P. Q C is a functional relationship, where Q C Determined by the rainstorm flood flow corresponding to the frequency P.

[0039] Peak flow of debris flow QC The calculation formula is: ; in, is the peak flow rate of debris flow with frequency P, in m³ / s; is the design flow rate of rainstorm flood with frequency P, in m³ / s; is the debris flow sediment correction coefficient, where ; is the bulk density of debris flow, in t / m³; is the specific gravity of clean water, in t / m³, with a value of 1.0; is the specific gravity of solid matter in debris flow, unit is t / m³; is the debris flow blocking coefficient; In this example, the impact column 1 adopts a variable cross-section design, wherein the main impact column cross-sectional area A at the axis is m satisfy: ; in, is the peak value of debris flow impact load; is the safety factor, take 1.5-2.0; The yield strength of the impact column material is the main impact column. The bending section strength of the main impact column should be 1.2-1.5 times that of the other impact columns, and its burial depth must meet the overturning stability requirements. In this example, the selected impact column 1 also needs to be matched with a sprinkler device 7, so a combined structure is adopted, including a lower solid impact column 8 and an upper hollow water storage column 9. Among them, the height H1 of the lower solid impact column 8 meets the following requirements: ; Where: h max is the maximum depth of debris flow in the basin; Δh is the safety overheight, which is 0.3-0.5m; the height of the upper hollow water storage column 9 H 2 Determined based on the demand for rainwater storage.

[0040] In this example, the sprinkler device mainly collects water from the source area and the ditch during rainy and snowy weather through the water inlet 11, collects the water into the upper hollow water storage column 9 through the water collecting pipe 6, and then sprays the water into the ecological retaining dam through the sprinkler device 7 for irrigation.

[0041] The sprinkler 7 draws water from the sprinkler connection port 13 through the sprinkler back pressure pumping device 14, and then sprays the water onto the ecological barrier dam through the spray hole 12. The spray hole spray direction can be adjusted by rotating the sprinkler body 15 to achieve uniform irrigation.

[0042] P104. Identify the dominant species in the watershed and conduct ecological design based on the main body of the sediment dam: In this example, trees and shrubs are selected for the first and second rows of the plant dam, arranged in two back-to-back fan rings. The ring width is the same as the diameter of the impact column base. The center of the upper fan ring is the centroid of the lower fan ring, and the center of the lower fan ring is the centroid of the upper fan ring. The entire plant dam 10 is constructed from a vegetated concrete base, which stabilizes the slope and prevents erosion.

[0043] P105. Conduct a small flume model test to calculate the energy reduction rate of debris flow caused by the energy dissipation system and test method: Among them, the energy dissipation system reduces the energy of debris flow by: ; in, W is the debris flow energy reduction rate in the basin; C is the debris flow energy experimental coefficient; is the volume fraction of solid particles; is the average particle size of solid particles, in m; is the bulk density of solid particles, in kN / m³; is the solid phase particle velocity, in m / s; is the bulk density of the liquid phase, in kN / m³; is the liquid phase flow rate, in m / s; is the angle between flow direction and flow velocity.

[0044] like Figure 5-6 As shown, the provenance area 20 for the small flume model experiment is divided into three parts: Source 1 21, Source 2 22, and Source 3 23. Source 1 is a landslide source (derived from collapse and landslide deposits); Source 2 is a transport-controlled source (derived from sediment replenishment); and Source 3 is a loose solid material-controlled source (derived from bedrock weathering). These three sources were placed in the provenance area of the small flume model and subjected to rainfall erosion to form debris flows. Experiments were conducted using different control groups for each of the three sources, with varying order of arrangement. All designs were scaled up for experimental purposes.

[0045] The provenance was a 1-meter-long, 1-meter-wide, and 0.8-meter-high plexiglass model box with a gate. Three source materials were sampled from 12 debris flow channels along the Minjiang River basin. Six different arrangements of these materials were combined, with and without barrier dams, for a total of 144 test sets. Each test simulated rainfall above the provenance at 50 mm / hour.

[0046] The circulation area uses a circulation trough with a length of 2 meters and a width of 20 centimeters, with a construction angle of 30°, connected to the gate of the source area at the top and the water trough of the accumulation area at the bottom. The configuration of the present invention is set at the midpoint of the circulation area, and the pore water pressure sensor 18 and the impact force sensor 19 are respectively set 20 and 30 centimeters above and below the configuration.

[0047] The stacking area uses a trough that is 3 meters long and 2 meters wide, with a construction angle of 5°.

[0048] The results show that the energy dissipation configuration technology and methods for debris flow impact force can reduce the debris flow impact force energy by 46.1%.

Claims

1. A geotechnical-biological synergistic energy dissipation system for landslide source-controlled debris flows, characterized by: The energy dissipation system (24) is arranged in a region connected to the debris flow in the basin. The energy dissipation system (24) is a multi-dimensional protection system consisting of a W-type filtration system (25), a main dam (4), a branch dam (3) and a plant dam (10); The main dam (4) is arranged inside the upper opening of the W-shaped filtering system (25), and the sub-dams (3) are arranged between adjacent main dams (4); The plant dam (10) is arranged inside the lower opening of the W-shaped filtering system (25); The W-shaped filtering system (25) is provided with a nozzle device for collecting water and a sprinkler device (7) for irrigation.

2. The rock-soil-biological synergistic energy dissipation system for landslide source-controlled debris flows according to claim 1, characterized in that: The W-shaped filtering system (25) comprises a plurality of impact columns (1) arranged in a W shape, wherein adjacent impact columns (1) located on the inner side are fixedly connected via an inner filter fence (5), and adjacent impact columns (1) located on the outer side are fixedly connected via an outer filter fence (2).

3. The rock-soil-biological synergistic energy dissipation system for landslide source-controlled debris flows according to claim 2, characterized in that: The main dam (4) is an arc-shaped structure composed of a gabion mesh and a landslide body in the watershed; the root of the main dam (4) is fixedly connected to the impact column (1), the size of the main dam (4) is half the opening size of the W-type filter system (25), and the angle formed with it is 45 degrees, and the cross section is an arc; The landslide bodies in the basin are blocks with a particle size greater than 40 mm.

4. The rock-soil-biological synergistic energy dissipation system for landslide source-controlled debris flows according to claim 3, characterized in that: The size of the sub-dam (3) is half of the main dam (4), and the angle formed with the W-shaped filtering system (25) is 60°, and the cut surface is a straight edge with a cut angle greater than 60°.

5. The rock-soil-biological synergistic energy dissipation system for landslide source-controlled debris flows according to claim 3, characterized in that: The plant dam (10) is a sand retaining dam formed by planting shrubs and trees on an ecological substrate; The shrubs and trees are arranged in a staggered, curved arc arrangement; There are two rows of plant dams (10), which are arranged in two back-to-back fan rings, wherein the width of the rings is the same as the diameter of the impact column (1), the center of the upper fan ring is the centroid of the lower fan ring; the center of the lower fan ring is the centroid of the upper fan ring, and the ecological base material of the base of the entire plant dam (10) is a vegetation concrete material.

6. The rock-soil-biological synergistic energy dissipation system for landslide source-controlled debris flows according to claim 3, characterized in that: The nozzle device includes a water collecting pipe (6), which is a water collecting pipe network formed by an inner filter fence (5) and an outer filter fence (2); A water inlet (11) is provided on the water collecting pipe (6) at the bottom. The water collecting pipe (6) is connected to the upper hollow water storage column (9). The upper hollow water storage column (9) is the upper structure of the impact column (1). The bottom of the upper hollow water storage column (9) is the lower solid impact column (8).

7. The rock-soil-biological synergistic energy dissipation system for landslide source-controlled debris flows according to claim 6, characterized in that: The sprinkler irrigation device (7) comprises a sprinkler irrigation device body (15), a sprinkler irrigation device connection port (13) is provided at the bottom of the sprinkler irrigation device body (15), the sprinkler irrigation device connection port (13) is connected to the upper hollow water storage column (9), a plurality of water spray holes (12) are provided on the outside of the sprinkler irrigation device body (15), and a sprinkler irrigation back-pressure pumping device (14) is provided on the top of the sprinkler irrigation device body (15).

8. A test method for geotechnical-biological synergistic energy dissipation of landslide source-controlled debris flows, characterized in that: The method is implemented by using the rock-soil-biological synergistic energy dissipation system according to any one of claims 1 to 7, comprising the following steps: Step 1: Conduct on-site sampling within the watershed to determine the particle size distribution within the watershed; Step 2: Select the appropriate filter based on particle size distribution; Step 3: Collect basic information about the watershed and design the size of the energy dissipation system; Step 4: Identify the dominant species in the watershed and conduct ecological design in conjunction with the energy dissipation system; Step 5: Conduct a small flume model test to calculate the energy reduction rate of the energy dissipation system on debris flow.

9. The test method for geotechnical-biological synergistic energy dissipation of landslide source-controlled debris flow according to claim 8, characterized in that: The on-site sampling in step 1 includes soil samples from the upper and lower layers of the provenance area (20), the circulation area (17), and the accumulation area (16) within the watershed; The provenance area provides material conditions for the formation of debris flows; The circulation area is used to change the movement characteristics of the debris flow; The accumulation area is used to provide a place for debris flow to stop and accumulate; The particle size distribution includes maximum particle size, minimum particle size, and average particle size; Wherein, in said step 2, the filter size P for: P =（ P max + P min ） / 2； Where, P max is the maximum particle size in the basin, P min is the minimum particle size in the watershed; The filter size of the outer filter fence (2) is set to P min ; In step 3, the basic information of the basin includes: hydrological conditions, climatic conditions, topography, geological environment, human conditions and disaster conditions; The hydrological conditions include river length, river direction, tributary shape, number of tributaries, river network density, river drop, and canyon distribution; The topography includes the type of terrain, relief, inclination, extreme value and altitude. In the step 3, when designing the size of the energy dissipation system, the opening angle θ of the W-type filter system (25) is related to the peak flow rate of the debris flow with a frequency of P. Q C is a functional relationship, where Q C Determined by the storm flood flow corresponding to the frequency P; Peak flow of debris flow Q C The calculation formula is: ； in, is the peak flow rate of debris flow with frequency P, in m³ / s; is the design flow rate of rainstorm flood with frequency P, in m³ / s; is the debris flow sediment correction coefficient, where ; is the bulk density of debris flow, in t / m³; is the specific gravity of clean water, in t / m³, with a value of 1.0; is the specific gravity of solid matter in debris flow, unit is t / m³; is the debris flow blocking coefficient; The impact column (1) adopts a variable cross-section design, wherein the main impact column cross-sectional area A at the axis is m satisfy: ； in, is the peak value of debris flow impact load; is the safety factor, take 1.5-2.0; The yield strength of the impact column material is the main impact column. The bending section strength of the main impact column should be 1.2-1.5 times that of the other impact columns, and its burial depth must meet the overturning stability requirements. The height H1 of the lower solid impact column (8) satisfies: ； where h max is the maximum depth of debris flow in the basin; Δh is the safety overheight, which is 0.3-0.5m; the height of the upper hollow water column (9) H 2 Determined based on the demand for rainwater storage.

10. The test method for geotechnical-biological synergistic energy dissipation of landslide source-controlled debris flow according to claim 9, characterized in that: The energy reduction rate of the debris flow by the energy dissipation system in step 5 is: ； in, W is the debris flow energy reduction rate in the basin; C is the debris flow energy experimental coefficient; is the volume fraction of solid particles; is the average particle size of solid particles, in m; is the bulk density of solid particles, in kN / m³; is the solid phase particle velocity, in m / s; is the bulk density of the liquid phase, in kN / m³; is the liquid phase flow rate, in m / s; is the angle between flow direction and flow velocity.

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