Debris flow impact resistance simulation test device and method

Abstract

The invention discloses a debris flow impact resistance simulation test device and method. The device comprises a material source stirring system, a model box, a traffic engineering structure and a data acquisition system, the material source stirring system is arranged above the model box, the top of the model box is open, a steel wire for three-coordinate point marking, a sliding rail, a ruler and a marked line are arranged in the model box, the traffic engineering structure is arranged at a debris flow flowing direction simulating terminal in the model box, and the data acquisition system is connected to the traffic engineering structure; the flow path before the debris flow impacts the traffic engineering structure is restored, the debris flow flow parameters are scientifically calculated and simulated, the whole test process is high in restoration degree, the impact effect of the debris flow under the complex working condition can be truly reflected, and the test result is accurate.

Description

Technical Field

[0001] The present invention belongs to the technical field of debris flow prevention and control, and specifically relates to a simulation test device and method for the impact resistance performance of debris flow. Background Art

[0002] Debris flow is a geological disaster with extremely strong destructiveness, and often poses a major threat to traffic engineering structures, especially key parts such as bridge piers and tunnel entrances. In order to study and improve the impact resistance ability of structures, the indoor test method has become an important means for studying debris flow impact mechanics due to its controllability and economy.

[0003] Although the existing indoor test devices have solved the problem of debris flow impact simulation to a certain extent, there are significant limitations in truly restoring the debris flow impact process, and it is difficult to comprehensively reflect the complex working conditions in actual engineering; traditional indoor debris flow tests usually use small inclined channels, and the tests are carried out under the idealized terrain conditions of the debris flow flow area, and the simplified structure model is impacted by the artificially manufactured debris flow model; although this kind of test is simple to operate and has a certain degree of controllability, there are significant deficiencies in simulating the dynamic characteristics of debris flow. The test device cannot simulate the influence of debris flow flow on the actual engineering terrain, resulting in the simulation effect being limited to standardized conditions and it being difficult to truly reflect the impact effect of debris flow under complex working conditions, making the test results deviate from the actual working conditions to a certain extent. Summary of the Invention

[0004] The purpose of the present invention is to provide a simulation test device and method for the impact resistance performance of debris flow to solve the problems raised in the above background art.

[0005] To achieve the above object, the present invention provides the following technical solution: A simulation test device for anti-debris flow impact performance, comprising a source material stirring system, a model box, a traffic engineering structure, and a data acquisition system; the source material stirring system includes a stirring container, a plurality of material bins, stirring blades, and a motor; the plurality of material bins are fixedly connected to the outer side wall of the stirring container, and each material bin is provided with a channel communicating with the inside of the stirring container, and an electric slide valve is arranged at the outlet of the channel; the stirring blades are rotatably connected inside the stirring container and the rotating shaft of the stirring blades is connected to the rotating shaft of the motor; a discharge port is arranged below the stirring container, and a baffle for closing the discharge port is connected to the discharge port through a hinge. The model box is fixedly arranged below the discharge port and the top of the model box is open. Two slide rails are symmetrically arranged inside the model box along the simulated debris flow direction. A plurality of manually bendable steel wires are horizontally arranged between the slide rails, and one end of the steel wire is fixedly connected to the bottom of the model box. A scale is vertically arranged on each slide rail, and a marking line is connected between the scales on the two slide rails. Scale lines are arranged on the slide rails, scales, and marking lines; the traffic engineering structure is fixedly connected to the inside of the model box through a fixture, and the traffic engineering structure is arranged at the terminal of the simulated debris flow direction; the data acquisition system includes sensors, a dynamic data acquisition device, and a high-precision imaging device. The sensors and the dynamic data acquisition device are fixedly connected to the traffic engineering structure, and the high-precision imaging device is fixedly arranged outside the model box for recording the process of the debris flow impact simulation experiment.

[0006] Further, a waste outlet is arranged at the terminal of the debris flow direction on the model box, a waste collection pool is arranged below the waste outlet, and a filter screen is arranged in the waste collection pool.

[0007] Setting the waste outlet facilitates the treatment of the simulated debris flow after the test.

[0008] Preferably, a gravity wall is vertically arranged outside the model box. The source material stirring system is fixedly connected to the top of the gravity wall, and the discharge port is suspended on the gravity wall.

[0009] Further, a telescopic screw rod is fixedly connected below the baffle.

[0010] Setting the telescopic screw rod facilitates adjusting the opening angle of the baffle, thereby controlling the initial flow angle of the simulated debris flow.

[0011] Further, a ladder is fixedly arranged on the side wall of the gravity wall.

[0012] Further, the fixture includes two clamping plates, which are connected by a screw rod and a nut. A permanent magnet is fixedly arranged on the outer side of the clamping plate. Magnetic attraction strips are arranged on both side surfaces of the model box. The clamping plate is fixedly connected inside the model box through magnetic attraction of the permanent magnet and the magnetic attraction strip.

[0013] Using magnetic materials to fix traffic engineering structures is flexible and convenient when adjusting the positions of traffic engineering structures.

[0014] Further, the model box is made of a transparent material.

[0015] Using a transparent material is convenient for observing and recording the test process.

[0016] A simulation test method based on an anti-debris flow impact performance simulation test device includes the following steps:

[0017] S1: Scale down the traffic engineering structure to be simulated against debris flow impact and fix it in the model box through a fixture;

[0018] S2: Detect the basic characteristic parameters of debris flow, including: debris flow density γ, solid matter density γ h , roughness coefficient n, sediment correction coefficient average mud depth H c , hydraulic gradient I c , maximum stone particle size d max , average gravel particle size d min , and select multiple ramp cross-section points on the debris flow flow path to measure the bottom width W d of each point cross-section and the actual flow width W l of the debris flow as well as the slope height H i ;

[0019] S3: Scale down the large stone particle size d max and the average gravel particle size d min , add the stones that meet the scaled-down size to the material bin, and according to the debris flow density γ h , add the stones, sand, soil, and water in the material bin to the mixing container through an electric slide valve to stir and make experimental simulated debris flow, measure the release height H of the simulated debris flow, and use the volume concentration method to measure the volume concentration φ of solid particles in the simulated debris flow to obtain the slope friction coefficient f;

[0020] S4: Use a rotational viscometer to measure the shear stress τ of the test debris flow model under different shear rates without coarse particles, and perform power-law model fitting through MATLAB. The form of the power-law model is:

[0021] Since the power-law model is non-linear, logarithmic transformation is used to convert it into a linear regression problem for convenient fitting. Use linear regression fitting: Take log(τ) as the dependent variable. As the independent variable, use linear regression to fit the model parameters.

[0022] The fitted model is: Where: The slope m = n p ; The intercept b = log(λ p ); Determine its rheological index n p and the proportionality coefficient λ of the yield stress to the shear rate p ;

[0023] Then use the correction formula to convert the rheological parameters of the slurry into the overall rheological parameters n and the proportionality coefficient λ of the shear rate of the debris flow containing coarse particles: n = n P ·(1 - α·φ C ), λ = λ p ·(1 + β·φ c ), φ c is the volume concentration of coarse particles; α is an empirical constant, taking values between 0.5 and 1.5 according to the type and concentration of coarse particles; β is an empirical constant, depending on the properties of coarse particles, taking values between 1 and 3.

[0024] S5: Calculate the average flow depth D of the debris flow. In the formula, W d is the width of the bottom of the selected cross-section valley; W l is the actual flow width of the debris flow in the selected cross-section; m is the number of selected cross-sections; H i is the slope height of the selected cross-section.

[0025] S6: Calculate the flow velocity V of the debris flow according to the basic characteristics of the debris flow. c : Based on the flow velocity scaling theory of the Froude similarity criterion, calculate the flow velocity index V required for the debris flow model impact simulation test. m , In the formula, V m is the flow velocity index of the debris flow model, and k is the scale ratio of the traffic engineering structure model; According to the rheological and dynamic parameter set of the debris flow model, based on the coupling control method of the debris flow impact velocity and rheological characteristics driven by the slope, and combined with the velocity index V m required for the debris flow model impact simulation test, calculate the inclination angle θ of the slope in the acceleration section of the simulated debris flow:

[0026] S7: Measure the flowing terrain in front of the debris flow impacting the traffic engineering structure on-site, and restore the terrain before the debris flow impact according to the backtracking algorithm. After scaling down the restored terrain dimensions, mark the three coordinates of each terrain dimension in the model box through the steel wires in the model box. Specifically, first bend up the steel wire at the corresponding position of the horizontal coordinate so that one end of the steel wire stands upright in the model box, then move the scale according to the vertical coordinate, adjust the height of the scale line on the scale to the height corresponding to the vertical coordinate, and mark the intersection point on the steel wire with a marker pen at the intersection of the steel wire and the scale line. Then continue to move the scale to mark the coordinates of the next terrain dimension;

[0027] S8: Manually fill and vibrate and compact in the model box according to the marked points on the steel wire to make a scaled-down debris flow flowing terrain, and make a debris flow acceleration section slope in the front section of the debris flow flowing terrain in the model box;

[0028] S9: Release the simulated debris flow in the stirring container, conduct a simulation test on the anti-debris flow impact performance, and record the test data through the data acquisition system.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] The present invention restores the flowing path of the debris flow before it impacts the traffic engineering structure through on-site measurement and using the backtracking algorithm. After scaling down, the spatial coordinates of the terrain dimensions are marked in the model box. When marking, the horizontal coordinate points are determined through the scale line, the corresponding steel wire is bent up, the longitudinal and vertical coordinate points are determined through the scale on the slide rail and the scale line, and then the terrain coordinates are marked on the steel wire by bending the steel wire and using a marker pen. The debris flow path is restored by manually filling according to the marked coordinate points. Finally, the flowing parameters of the simulated debris flow are scientifically calculated. The whole test process has a high degree of restoration, can truly reflect the impact effect of the debris flow under complex working conditions, and the test results are accurate. Description of the Drawings

[0031] Figure 1 is a schematic diagram of the overall structure of the simulation test device for anti-debris flow impact performance provided by the embodiment of the present invention;

[0032] Figure 2 is a flowchart of the simulation test method for anti-debris flow impact performance provided by the embodiment of the present invention;

[0033] Figure 3 is a schematic diagram of the material source stirring system structure provided by the embodiment of the present invention;

[0034] Figure 4 is a top view of the slide rail and the steel wire provided by the embodiment of the present invention;

[0035] Figure 5 is a schematic diagram of the scale and the scale line structure provided by the embodiment of the present invention;

[0036] Figure 6 It is a schematic diagram of the fixture structure provided by an embodiment of the present invention;

[0037] In the figure, 1 - source stirring system, 2 - model box, 3 - traffic engineering structure, 4 - gravity wall, 5 - fixture, 6 - waste collection pool, 11 - stirring container, 12 - material bin, 13 - stirring blade, 14 - motor, 15 - baffle, 16 - telescopic screw, 21 - slide rail, 22 - steel wire, 23 - scale, 24 - marking line, 25 - graduation line, 41 - ladder, 51 - clamping plate, 52 - screw, 53 - nut, 54 - permanent magnet. Specific embodiments

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] Please refer to Figures 1-6 , the present invention provides a technical solution: an anti-debris flow impact performance simulation test device, including a source stirring system 1, a model box 2, a traffic engineering structure and a data acquisition system. A gravity wall 4 is vertically arranged outside the model box. The source stirring system 1 is fixedly connected to the top of the gravity wall 4, and ladders 41 for facilitating manual inspection of the source stirring system 1 are arranged on both sides of the gravity wall 4.

[0040] The source stirring system 1 includes a stirring container 11, four material bins 12, stirring blades 13 and a motor 14; the four material bins 12 are fixedly connected to the outer side wall of the stirring container 11 along the circumferential direction of the stirring container 11, and each material bin 12 is provided with a channel communicating with the inside of the stirring container 11, and an electric slide valve is arranged at the outlet of the channel; the stirring blades 13 are rotatably connected inside the stirring container 11 and the rotating shaft of the stirring blades 13 is connected to the rotating shaft of the motor 14; a discharge port is arranged below the stirring container 11, the discharge port is suspended from the gravity wall, and a baffle 15 for closing the discharge port is connected to the discharge port through a hinge. A sealing strip is arranged on the baffle 15 to prevent material leakage. A telescopic screw 16 for controlling the opening angle of the baffle 15 is arranged below the baffle 15, and a plug is arranged at the front end of the baffle 15 and inserted and fixed with the stirring container 11.

[0041] The model box 2 is made of transparent material and is fixedly arranged below the discharge port. The top of the model box 2 is open. Inside the model box 2, two slide rails 21 are symmetrically arranged along the simulated debris flow direction. Between the slide rails 21, a plurality of manually bendable steel wires 22 are horizontally arranged, and one end of the steel wire 22 is fixedly connected to the bottom of the model box 2. On each slide rail 21, a scale 23 is vertically arranged, and a marking line 24 is connected between the scales 23 on the two slide rails 21. Scale lines 25 are arranged on the slide rails 21, scales 23 and marking lines 24.

[0042] In order to facilitate the collection of test waste, a waste outlet is arranged at the terminal of the debris flow direction on the model box 2 of the present invention. A waste collection pool 6 is arranged below the waste outlet, and a filter screen is arranged in the waste collection pool 6 to filter the stones in the simulated debris flow, which is convenient for treatment.

[0043] The traffic engineering structure 3 is fixedly connected to the inside of the model box 2 through a fixture 5, and the traffic engineering structure 3 is arranged at the terminal of the simulated debris flow direction; the fixture 5 includes two clamping plates 51, which are connected by a screw 52 and a nut 53 between the clamping plates 51. A permanent magnet 54 is fixedly arranged on the outer side of the clamping plate 51. Magnetic attraction strips are arranged on both sides of the model box 2, and the clamping plate 51 is fixedly connected to the inside of the model box 2 through the magnetic attraction of the permanent magnet 54 and the magnetic attraction strip.

[0044] The data acquisition system includes sensors, a dynamic data collector and a high-precision imaging device. The sensors and the dynamic data collector are fixedly connected to the traffic engineering structure, and the high-precision imaging device is fixedly arranged outside the model box 2 for recording the process of the debris flow impact simulation experiment.

[0045] Example 1: The present invention conducts a simulation test on the anti-debris flow impact performance based on the actual engineering design of the No. 34 pier of the Daleigou Extra-large Bridge on the Mianjiu Expressway. The pier is a pile-column integrated pier, with a pier column height of 12.391 m and a diameter of 1.6 m; the pier model is made according to a scale of 1:40 and is clamped in the model box through a fixture. The height of the pier column model is 309.775 mm and the diameter is 40 mm. The material is selected as C35 concrete, and the reinforcement ratio is 1.34%.

[0046] According to the field investigation, combined with data and experiments, the basic characteristics of the debris flow at the pier location are determined. The basic characteristics of the Daleigou debris flow are shown in Table 1;

[0047] Table 1 Basic characteristics of the Daleigou debris flow

[0048]

[0049] According to the basic characteristic parameters of the debris flow, the raw materials for the test debris flow are configured. The mass ratio of the raw materials for the test debris flow in this test is 5:4:1:6.79 (stone: sand: soil: water), and the fluid density is 1703 kg / m3 , coarse-grained granite stones with a particle size of 20-32.5mm were used to simulate large stones, and fine-grained granite stones with a particle size of 2-2.5mm were used to simulate crushed stones, with the ratio of the two being 4:6. The specific composition of debris flow raw materials is shown in Table 2;

[0050] Table 2 Composition of debris flow raw materials

[0051]

[0052] The rheological and dynamic parameter sets of the Daleigou debris flow model are clarified, see Table 3:

[0053] (1) Determine the release height of the simulated debris flow: H = 3m;

[0054] (2) The solid particle volume concentration of the Daleigou debris flow model was measured by the volume concentration method: φ = 0.31;

[0055] (3) Consult relevant literature and engineering reports to obtain empirical data, and use the analogy method to calculate and determine the slope friction coefficient: f = 0.3;

[0056] (4) Using a rotational viscometer to measure the different shear rates of the experimental Daleigou debris flow model without coarse particles The shear stress τ under the condition is fitted by the power law model through MATLAB to determine its rheological index n p =0.4, the proportionality coefficient of yield stress and shear rate λ p =0.169Pa·s n ;

[0057] The modified formula is then used to convert the slurry rheological parameters into the overall rheological parameters n of the debris flow containing coarse particles and the proportional coefficient λ of the shear rate: n = n P ·(1-α·φ C ),λ=λ p ·(1+β·φ c ), φ c is the volume concentration of coarse particles, which is taken as φ c =0.117; α is an empirical constant, which is determined by the type and concentration of coarse particles; β is an empirical constant, which depends on the properties of the coarse particles. Because the proportion of coarse particles in the simulated debris flow in this experiment is large and the particle size is large, α is taken as 1.2 and β is taken as 2 to reflect the interaction between particles and their influence on rheological parameters.

[0058] (5) The main channel section of the Daleigou debris flow is a typical "V"-shaped valley. The slope structure is scaled and restored by backtracking algorithm, and the depth of multiple representative cross sections is measured by field measurement to calculate and determine the overall average flow depth of the debris flow:

[0059] D = 0.3 m;

[0060] Table 3 Rheological and Kinetic Parameter Set of Daleigou Debris Flow

[0061]

[0062] Calculate the actual debris flow velocity, V c = 8.2 m / s; Based on the velocity scaling theory of Froude similarity criterion, calculate the simulated debris flow velocity index:

[0063] V m = 1.297 m / s.

[0064] Since the flow path of the debris flow is relatively long, when conducting the test on the anti-debris flow impact performance of the traffic engineering structure 3, only a small part of the debris flow path in the front section of the traffic engineering structure 3 needs to be restored, and a simulated debris flow acceleration slope is set at the front end of the restored path, so that when the simulated debris flow flows to the restored path, the debris flow velocity meets the simulation requirements; According to the rheological and kinetic parameter set of the debris flow model, based on the coupling control method of the debris flow impact velocity and rheological characteristics driven by the slope, and combined with the velocity index required for the debris flow impact test simulation, calculate and determine the inclination angle θ of the slope structure in the acceleration section: θ = 23.62°.

[0065] Field measure the flow topography in front of the debris flow impact pier and restore the topography before the debris flow impact according to the backtracking algorithm. After scaling the restored topography dimensions, mark the three coordinates of each topography dimension on the model box 2 through the steel wire 22 in the model box in turn. Specifically, first lift the steel wire 22 at the corresponding horizontal coordinate position so that one end of the steel wire 22 stands upright in the model box 2, and then move the scale 23 according to the vertical coordinate, adjust the height of the marking line 24 on the scale 23 to the height corresponding to the vertical coordinate, and mark the intersection point on the steel wire 22 with a marker pen at the intersection of the steel wire 22 and the marking line 24, and then continue to move the scale 23 to mark the coordinates of the next topography dimension;

[0066] Then, manually fill and vibrate and compact according to the marked points on the steel wire 22 in the model box 2 to make the scaled debris flow flow topography, and make a debris flow acceleration slope in the front section of the debris flow flow topography in the model box 2. The end of the acceleration slope is docked with the starting end of the topography before the debris flow impact after restoration and the inclination angle θ of the acceleration slope is 23.62°, and before the test, the surface of the acceleration slope and the simulated debris flow topography are leveled with cement mortar and wetted with water;

[0067] Add the simulated debris flow raw materials (stone materials, sand materials, soil materials, water) to the material bin 12, regulate the raw material feeding amount through the slide valve, so that the ratio of stone materials, sand materials, soil materials, and water meets 5:4:1:6.79, and start the motor to mix and stir the materials for 5 minutes through the stirring blades 13 to ensure the uniformity of material mixing.

[0068] Adjust the length of the telescopic screw 16 at the lower end of the baffle 15 so that one end of the telescopic screw 16 abuts against the gravity wall 4, thereby controlling the opening angle of the baffle 15 to make the angle of the baffle 15 conform to the slope angle θ = 23.62° of the acceleration section. In this embodiment, the length of the telescopic screw 16 where a is the vertical distance from the threaded telescopic rod 16 to the connecting hinge of the baffle 15, a = 0.686m;

[0069] Finally, open the bolt on the baffle 15 to release the simulated debris flow in the stirring container 11, conduct a simulation test on the anti-debris flow impact performance, and record the test data through the data acquisition system.

[0070] It should be noted that the present invention scientifically calculates the flow velocity of the debris flow finally impacting the traffic engineering structure 3 in the actual project, then scales the test flow velocity, and combines the coupling control method of the debris flow impact velocity and rheological characteristics based on slope drive to accurately calculate and set the inclination angle of the slope structure. This method ensures that the debris flow model reaches the designed flow velocity during the test process. This method is specially designed for the test device of the anti-debris flow impact performance of the indoor traffic engineering structure 3, and shows excellent applicability within a reasonable parameter range. Specifically, this method is applicable to the simulated slopes with the slope inclination angle below 45°, the recommended setting range of the friction factor is 0.01 to 0.3, and the applicable particle diameter is 2mm to 60mm.

[0071] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A debris flow resistance simulation test device, characterized in that: It includes a material source stirring system, a model box, a traffic engineering structure and a data acquisition system; the material source stirring system includes a stirring container, multiple material bins, stirring blades and a motor; the multiple material bins are fixedly connected to the outer wall of the stirring container, and each material bin is provided with a channel connected to the interior of the stirring container, and an electric slide valve is provided at the outlet of the channel; the stirring blade is rotatably connected to the interior of the stirring container and the rotating shaft of the stirring blade is connected to the rotating shaft of the motor; a discharge port is provided below the stirring container, and a baffle for closing the discharge port is connected to the discharge port through a hinge, the model box is fixedly arranged below the discharge port and the top of the model box is open, and the interior of the model box is along the simulated debris flow flow direction. Two slide rails are symmetrically arranged, and a plurality of manually bendable steel wires are horizontally arranged between the slide rails, and one end of the steel wire is fixedly connected to the bottom of the model box, a ruler is vertically arranged on each of the slide rails, and a marking line is connected between the rulers on the two slide rails, and scale lines are arranged on the slide rails, the rulers and the marking lines; the traffic engineering structure is fixedly connected to the inside of the model box by a clamp, and the traffic engineering structure is arranged at the terminal of the simulated debris flow flow direction; the data acquisition system includes a sensor, a dynamic data collector and a high-precision imaging device, the sensor and the dynamic data collector are fixedly connected to the traffic engineering structure, and the high-precision imaging device is fixedly arranged on the outside of the model box for recording the debris flow impact simulation experiment process.

2. The anti-debris flow impact performance simulation test device according to claim 1 is characterized in that: A waste opening is arranged at the end of the debris flow direction on the model box, a waste collection pool is arranged below the waste opening, and a filter screen is arranged in the waste collection pool.

3. The anti-debris flow impact performance simulation test device according to claim 1 is characterized in that: A gravity wall is vertically arranged outside the model box, the source stirring system is fixedly connected to the top of the gravity wall, and the discharge port is suspended on the gravity wall.

4. The anti-debris flow impact performance simulation test device according to claim 3 is characterized in that: A telescopic screw is fixedly connected below the baffle.

5. The anti-debris flow impact performance simulation test device according to claim 4 is characterized in that : A ladder is fixedly arranged on the side wall of the gravity wall.

6. The debris flow resistance simulation test device according to claim 1 is characterized in that: The clamp includes two clamps, which are connected by screws and nuts. Permanent magnets are fixedly arranged on the outer sides of the clamps. Magnetic strips are arranged on both sides of the model box. The clamps are magnetically fixedly connected to the inside of the model box through permanent magnets and magnetic strips.

7. The debris flow resistance simulation test device according to claim 1 is characterized in that: The model box is made of transparent material.

8. A simulation test method based on the debris flow impact resistance simulation test device according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: The traffic engineering structure to be simulated to resist the impact of debris flow is scaled and fixed in the model box by a clamp; S2: Detection of basic characteristic parameters of debris flow, including: debris flow bulk density γ, solid matter bulk density γ h , roughness coefficient n, sediment correction coefficient φ, average mud depth H c 、Hydraulic slope I c , Maximum stone particle size d max , average particle size of crushed stone d min , and select multiple slope cross-section points on the debris flow path, and measure the valley bottom width W of each cross-section point d and the actual flow width W of the debris flow l And the slope height H i ; S3: The large stones are sized d max and the average particle size of the crushed stone min Scale down, add the stones of the scaled size into the material bin, and then calculate the size of the debris flow according to the specific gravity γ h , add the stone, sand, soil and water in the material bin into the mixing container through the electric slide valve to mix and produce the simulated debris flow for the experiment, measure the height H of the simulated debris flow release, and use the volume concentration method to determine the volume concentration φ of the solid particles in the simulated debris flow to obtain the slope friction coefficient f; S4: Using a rotational viscometer to measure the shear rate of the experimental debris flow model without coarse particles The shear stress τ under the condition is fitted by a power law model through MATLAB, and the form of the power law model is: Since the power law model is nonlinear, logarithmic transformation is used to transform it into a linear regression problem for easy fitting. Use linear regression fitting: take log(τ) as the dependent variable, As independent variables, linear regression was used to fit the model parameters; The fitted model is: Where: slope m = n p ; intercept b = log(λ p ) ; determine its rheological index n p and the proportionality coefficient λ of yield stress and shear rate p ; The modified formula is then used to convert the slurry rheological parameters into the overall rheological parameters n of the debris flow containing coarse particles and the proportional coefficient λ of the shear rate: n = n P ·(1-α·φ C ),λ=λ p ·(1+β·φ c ), φ c is the volume concentration of coarse particles; α is an empirical constant, which takes values ​​between 0.5 and 1.5 according to the type and concentration of coarse particles; β is an empirical constant, which takes values ​​between 1 and 3 depending on the properties of the coarse particles; S5: Calculate the average flow depth D of debris flow, Where W d is the selected cross-section valley width; W l is the actual flow width of the debris flow in the selected cross section; m is the number of selected cross sections; H i is the selected cross-section slope height; S6: Calculate the velocity V of the debris flow based on the basic characteristics of the debris flow c : Based on the velocity scaling theory of Froude similarity criterion, the velocity index V required for the debris flow model impact simulation test is calculated. m , Where V m is the velocity index of the debris flow model, k is the scale ratio of the traffic engineering structure model; according to the rheological and dynamic parameter set of the debris flow model, the coupling control method of the debris flow impact velocity and rheological characteristics driven by the slope is combined with the velocity index V required to be achieved in the debris flow model impact simulation test. m , calculate the inclination angle θ of the slope in the acceleration section of the simulated debris flow: S7: Measure the flow terrain in front of the debris flow impacting the traffic engineering structure on the spot and restore the terrain before the debris flow impact according to the backtracking algorithm. After scaling down the restored terrain size, mark the three coordinates of each terrain size in the model box in turn through the steel wire in the model box. Specifically, first pull up the steel wire at the position corresponding to the horizontal coordinate so that one end of the steel wire stands upright in the model box, then move the ruler according to the vertical coordinate, adjust the height of the marking line on the ruler to the height corresponding to the vertical coordinate, and mark the intersection of the steel wire and the marking line on the steel wire with a marker pen, and then continue to move the ruler to mark the coordinates of the next terrain size; S8: Artificially stack and vibrate the model box according to the marking points on the steel wire to produce a scaled debris flow terrain, and produce a debris flow acceleration section slope at the front section of the debris flow terrain in the model box; S9: Release the simulated debris flow in the mixing container, conduct a simulation test on the anti-debris flow impact performance, and record the test data through the data acquisition system.

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