A method and system for simulating large deformation of landslide dam instability disaster under extreme working conditions

Abstract

The present invention proposes a method and system for simulating large deformations caused by dam instability disasters under extreme working conditions, including the following steps: 1. constructing a solid model and discretizing it into an equidistant particle model; assigning basic parameter values and setting particle types to each particle; 2. constructing a universal constitutive model that characterizes the fluidization phase transition behavior of the soil; 3. using dam soil particles, dam rock particles, vehicle particles, and rolling stone particles as central particles, performing particle contact judgment, and simulating the deformation behavior of the central particles based on the constructed universal constitutive model that characterizes the fluidization phase transition behavior of the soil; and 4. visualizing and outputting the calculated characteristic information of each central particle. The present invention establishes a refined numerical simulation method for large deformations caused by dam instability disasters that takes into account the combined effects of landslide hazard chain impacts, vehicle loads, and rolling stone impacts. This method can predict the stability of dams and the subsequent large deformation failure process under extreme working conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of landslide simulation, and in particular to a method and system for simulating large deformation of a landslide dam caused by instability disaster under extreme working conditions. Background Art

[0002] Landslides, mudslides, and debris flows generated by dynamic geological processes on river valley banks, moraine produced by glacial snowmelt, and volcanic eruptions form natural dams that laterally block the valley riverbed, forcibly blocking the original water system and causing waterlogging in the upstream section. This natural dam is called a landslide dam. Currently, calculating the slope stability and large deformation of a landslide dam is a key component in assessing the safety of a landslide dam. Landslide dams are formed by landslides blocking the river, indicating the potential for secondary landslide triggering at the dam site. In the face of potential natural disasters such as secondary landslides, rockfall, the impact of emergency vehicle loads, or other extreme conditions, the landslide dam may become unstable. Once the landslide dam becomes unstable and collapses, the upstream impounded lake will quickly collapse in a short period of time, triggering an outburst flood, seriously threatening the safety of life and property of people living downstream and the safe operation of hydropower projects in the basin.

[0003] In recent years, some progress has been made in the calculation of landslide dam slope stability and large deformations, but several challenges and difficulties remain. First, regarding the research progress on landslide dam slope stability, relatively comprehensive slope stability analysis methods have been established, but these methods often only perform static analysis during the small deformation phase. Traditional slope stability analysis relies primarily on empirical formulas and simplified methods, such as the limit equilibrium method. However, these methods have limitations when considering complex geological conditions and nonlinear effects, making it difficult to accurately characterize the soil-rock mixture structure within the landslide dam. Large deformation calculation involves quantitatively describing and predicting the deformation process of a landslide dam under conditions such as slip, scour, and failure. With the continuous advancement of computer technology and numerical simulation methods, numerical methods such as mesh-based methods such as finite element analysis, meshless methods such as smoothed particle hydrodynamics, discrete element method, and discontinuous deformation analysis have gradually developed, making it possible to simulate the deformation of landslide dams during instability. However, mesh-based methods suffer from mesh distortion when dealing with large deformations, and the cost of re-meshing is prohibitive. Therefore, they are only suitable for stability analysis before large deformations occur and cannot evaluate the large deformation process after a landslide dam fails. The particle-based method can handle large deformation problems well and can simulate and analyze the instability mechanism and large deformation behavior of landslide dams.

[0004] However, there are still some difficulties and challenges in calculating the stability and large deformation of landslide dam slopes, such as the characterization of the heterogeneous properties of the internal materials of the landslide dam, especially the influence of the rocks inside the landslide dam. In existing simulations of landslide dams, the landslide dam is often treated as a homogeneous material, and its deformation behavior is simulated using a single soil material. This is inconsistent with the actual situation of particle sorting and the generation of different particle sizes during the accumulation and formation of the landslide dam. In addition, for the impact load of rolling stones and the moving load of vehicles during emergency response, current numerical simulations usually equate such loads with load boundaries, making it difficult to consider the dynamic coupling between vehicles and rolling stones and the landslide dam, such as the influence of the shape and size of the rolling stones, and the location of occurrence. There is a lack of numerical simulation methods for quantifying the damage of the landslide dam, judging its stability, and calculating the subsequent large deformation under such calculation loads. Under extreme loads such as secondary landslides, rockfall, and vehicle loads, will a landslide dam continue to block the river and maintain stability, or will it fail and fail? These processes involve the critical transformation of the landslide dam hazard chain. Currently, there is no unified standard for determining the critical evolution of the landslide and landslide dam hazard chain. Existing hazard chain evolution determinations are mainly carried out through statistical analysis, mathematical models, and refined models. Statistical analysis methods use big data analysis based on landslide and river blocking databases to determine whether the river is blocked, which is subjective. Mathematical models mainly use a series of critical discriminant formulas for landslide and river blocking, but there is no unified form for discriminant evaluation criteria and parameter selection. Refined models have gradually developed in recent years, such as SPH (smoothed particle hydrodynamics), DEM (discrete element method), and MPM (material point method) simulations. However, these methods currently lack mechanistic considerations, such as the random distribution of rocks, particle sorting, and constitutive model optimization. Summary of the Invention

[0005] The present invention is made to solve the above problems, and its purpose is to provide a method and system for simulating large deformation caused by instability disaster of landslide dam under extreme working conditions, so as to solve the problems in actual engineering that it is difficult to simulate large deformation caused by instability of landslide dam under extreme working conditions, difficult to predict the critical process of landslide dam disaster, difficult to characterize dynamic loads such as rolling stones and vehicles, and over-simplified modeling of soil and rock materials of landslide dam.

[0006] To achieve the above object, the technical solution of the method of the present invention is:

[0007] A method for simulating large deformation of a landslide dam under extreme working conditions due to instability disasters includes the following steps:

[0008] Step 1. Construct a 3D solid model of the landslide dam, a 3D solid model of the terrain, a 3D solid model of the vehicle, a 3D solid model of the rolling stone, a 3D solid model of the water flow, and a secondary landslide model respectively, and discretize them into equidistant particle models; assign basic parameter values to each particle and set the particle type;

[0009] Step 2. Construct a general constitutive model to characterize the fluidization phase transition behavior of soil;

[0010] Step 3. Using the landslide dam soil particles, landslide dam rock particles, vehicle particles, and rolling stone particles as the central particles, particle contact judgment is performed. The deformation behavior of the central particles is simulated based on the constructed universal constitutive model that characterizes the fluidization phase transition behavior of the soil, and the characteristic information of different central particles is coupled and calculated respectively.

[0011] Step 4. Visualize the characteristic information of each central particle obtained by calculation and control it by particle type to achieve material output classification.

[0012] Furthermore, in step 1, a plurality of real rocks are three-dimensionally scanned to establish a rock database, and a three-dimensional solid model of the landslide dam with random positions, random shapes and specified rock content is generated within the landslide dam;

[0013] Obtain the contour lines or elevation point information of the established three-dimensional terrain and fit it into a closed entity model, and generate a three-dimensional terrain entity particle model through a particle filling algorithm;

[0014] The vehicle 3D solid model, rolling stone 3D solid model, secondary landslide body model and water flow solid model are built into high-fidelity models according to the actual model size and the particle filling algorithm is used to generate the vehicle 3D solid particle model, rolling stone 3D solid particle model, secondary landslide body particle model and water flow solid particle model respectively.

[0015] Furthermore, the step 1 includes landslide particles, water flow particles, terrain particles, dam particles and dynamic boundary particles, and the dam particles include landslide dam soil particles and landslide dam block stone particles.

[0016] The dynamic boundary particles include rolling stone particles, rock particles inside the dam, and vehicle particles.

[0017] Furthermore, the basic parameters set for the landslide particles in step 1 include: density, internal friction angle, cohesion, elastic modulus, Poisson's ratio, and friction coefficient;

[0018] The basic parameters set for water flow particles include: density, viscosity;

[0019] Setting basic parameters for terrain particles includes: density, stiffness, friction coefficient;

[0020] The basic parameters set for dam particles include density, internal friction angle, cohesion, elastic modulus, Poisson's ratio, and friction coefficient;

[0021] The basic parameters set for dynamic boundary particles include density, stiffness, and friction coefficient.

[0022] Furthermore, the general constitutive model for characterizing the fluidization phase change behavior of soil in step 2 is:

[0023]

[0024] in, is the total stress; p solid is the spherical stress of the solid constitutive model; δ αβ is a piecewise function, α and β represent the vector direction of stress, when α=β, δ αβ The value is 1, otherwise it is 0; is the deviatoric stress of the solid constitutive model; p fluid is the constitutive pressure of the fluid; is the constitutive shear stress of the fluid; To characterize the stress before the soil of the landslide dam loses stability, that is, the solid constitutive stress, its value is σ critical is the stress intensity value when the material is in the critical state, which can be obtained through geotechnical engineering tests. Its value is is the real-time shear strain rate of the landslide dam soil; is the critical shear strain rate of the landslide dam soil, which can be obtained through geotechnical engineering tests; critical is the spherical stress when the soil is in the critical state, is the shear stress when the soil is in a critical state.

[0025] Furthermore, the particle contact determination in step 3 includes:

[0026] All particle contact types are judged. If the particle radius is r, the particle's influence domain is 2r. That is, contact calculation is performed when the distance between two particles does not exceed 2r, and the contact effect between the two particles is calculated.

[0027] Furthermore, the step 3 of simulating the deformation behavior of the central particle based on the constructed general constitutive model for characterizing the fluidization phase change behavior of the soil includes:

[0028] Taking the dam soil particle, landslide soil particle or water particle as the central particle i, the control equation is as follows:

[0029]

[0030]

[0031] Where: ρ i is the density of the central particle i; t is the calculation time; m j is the mass of particle j; is the velocity difference between the central particle i and the surrounding particles j in the influence domain, i.e. The direction is β direction; D ij,βis a smooth kernel function, representing the weight value of all particles j in the β direction within the influence domain centered on particle i; x is the position coordinate of the base point, is the displacement of particle i in the β direction; is the velocity gradient of the central particle i, that is, the acceleration of particle i; is the stress tensor of particle i, is the stress tensor of particle j, is the pressure of particle j, is the shear stress of particle j, g α is the acceleration of gravity; α and β represent the vector direction of stress. Stress is a third-order tensor. Both α and β can correspond to the x, y, and z directions. D is the area of soil particles in the landslide dam, L is the area of soil particles in the landslide, W is the area of water particles, DB is the dynamic boundary area of boulders, vehicles on the dam top, and rolling stones, and SB is the static boundary area of particles in the terrain.

[0032] Taking the rock particle of the landslide dam as the central particle k, the control equation is as follows:

[0033]

[0034]

[0035]

[0036] Where, ρ k is the density of the central particle k; is the velocity difference between the central particle k and the particles j in the surrounding influence domain, i.e. D kj,β The weight values of all particles j in the influence area centered on particle k in the β direction; is the displacement of particle k in the β direction; rock A has mass M A , speed V A , inertia tensor I A , angular velocity Ω A and the center of gravity R A ;m k is the mass of the central particle k; p k αβ is the pressure of particle k, τ k αβ is the shear stress of particle k, σ j αβ is the stress of particle j, f rock,j→k is the force exerted by the rest of the dam's rocks on particle k on rock A, f Vehicle,j→k is the force exerted by the vehicle on the dam top on particle k on the rock A, f debris,j→k is the force exerted by the rolling stone on particle k on the stone A; r kis the center of gravity of particle k.

[0037] Taking the vehicle particle or rolling stone particle k' as the central particle, the control equation is as follows:

[0038]

[0039]

[0040]

[0041] Where, ρ k' is the density of the central particle k'; is the velocity difference between the central particle k' and the surrounding particles j in the influence domain, i.e. D k'j,β is the weight value of all particles j in the influence area centered on particle k' in the β direction; is the displacement of particle k' in the β direction; m k' is the mass of the central particle k'; p k' αβ is the pressure of particle k', τ k' αβ is the shear stress of particle k', f rock,j→k is the force exerted by the rest of the dam's rocks on the particle k' on rock A, r k' is the center of gravity of particle k'.

[0042] Furthermore, f rock,j→k 、f Vehicle,j→k 、f debris,j→k The following formula can be used for calculation:

[0043] f rock,j→k =f n,ij +f t,ij

[0044]

[0045]

[0046] Where, is the normal stiffness coefficient related to the elastic modulus, Poisson's ratio and particle radius, is the normal damping constant, e ij is the coefficient of restitution, k t,ij =2 / 7k n,ij is the tangential stiffness coefficient, γ n,ij =2 / 7γ n,ij is the tangential damping coefficient, δ ij =max(0,(d i +d j ) / 2-|rij |) is the intrusion distance between particles, which is used to characterize the degree of collision between particles, e ij is a unit vector, is the normal deformation rate. The tangential contact force is given by:

[0047]

[0048] Furthermore, step 4 includes: calculating the field variable information of each particle through the smooth particle fluid dynamics method, and the obtained information is digital text information, which is converted into a binary VTK file output for visualization, wherein the particle output of different partitions is controlled by the particle type to realize material output classification.

[0049] In another aspect, the present invention provides a system for simulating large deformation of a landslide dam under extreme working conditions due to instability disasters, comprising:

[0050] Particle model construction module: It is used to construct the 3D solid model of the landslide dam, the 3D solid model of the terrain, the 3D solid model of the vehicle, the 3D solid model of the rolling stone, the solid model of the water flow, and the secondary landslide body, and discretize them into equidistant particle models; assign basic parameter values to each particle and set the particle type;

[0051] Constitutive model building module: It is used to build a general constitutive model to characterize the fluidization phase change behavior of soil;

[0052] Coupling calculation module: It is used to determine particle contact using landslide dam soil particles, landslide dam block particles, vehicle particles, and rolling stone particles as central particles. It simulates the deformation behavior of central particles based on the constructed universal constitutive model that characterizes the fluidization phase change behavior of soil, and performs coupled calculations on the characteristic information of different central particles.

[0053] Visualization output module: It is used to visualize the characteristic information of each central particle obtained by calculation, and control it by particle type to realize material output classification.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] (1) The present invention breaks through the limitations of traditional methods for calculating the dynamic load of landslide dams, which are overly simplified and the grid method is not suitable for processing large deformation calculations. A universal constitutive model that can characterize the behavior of soil, fluid and soil phase change is proposed. The fluid-solid coupling mechanism between landslide, water flow and landslide dam is considered, and a refined numerical simulation method for large deformation of landslide dam instability disaster is established, which takes into account the combined effects of landslide disaster chain impact, vehicle load and rolling stone impact. The method can predict the stability of landslide dams under extreme working conditions and the subsequent large deformation damage process.

[0056] (2) The present invention solves the difficult problem of unclear critical transformation conditions and inconsistent judgment criteria for the disaster chain of landslide-dam disasters, and proposes a method for predicting the critical transformation process of landslide-dam disasters under extreme working conditions. Considering the impact of secondary landslides, rockfall impacts and vehicle loads on existing landslide-dams, a "landslide-rockfall and vehicle-dam" coupled large deformation calculation model is established. The method can predict the disaster chain transformation process of secondary landslides, rockfall impacts and vehicle loads that induce the instability and collapse of landslide-dams or further blockage of rivers, and reveals the mechanism by which secondary landslides, rockfall impacts and vehicle loads promote or delay the instability of landslide-dams, which can provide a tool for risk assessment and early warning of landslide instability.

[0057] (3) The present invention avoids the traditional method's assumption that landslide rockfall impact loads and vehicle loads are equivalent to concentrated force boundaries. It establishes a real landslide body, rockfall impact and vehicle movement load model, calculates the dynamic response and deformation characteristics of the landslide dam under dynamic loads, and truly reconstructs the damage evolution process of the plastic zone inside the landslide dam under extreme loads. This method solves the engineering problem of difficult safety assessment of landslide dams under extreme working conditions.

[0058] (4) The present invention breaks through the limitations of ignoring the influence of real rocks in the traditional landslide dam modeling process, or using generalized models in the rock modeling process, which are highly subjective, have uncertainties, and are divorced from engineering practice. This patent provides a high-fidelity modeling method for landslide dams that takes rock distribution into consideration. By randomly arranging rocks in the landslide dam, a three-dimensional model of the landslide dam that takes into account the real rock shape and different rock contents is constructed, ultimately forming a high-fidelity modeling method for landslide dams. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0060] Figure 1 Schematic diagram of the particle model in an embodiment of the present invention.

[0061] Figure 2 Schematic diagram of a high-fidelity model of a landslide dam containing random real rocks according to an embodiment of the present invention.

[0062] Figure 3 Schematic diagram of the coupled contact between landslide, water flow, terrain, dam, rockfall and vehicle in an embodiment of the present invention.

[0063] Figure 4 Schematic diagram of the evolution of the sand column collapse velocity field and slope line comparison at different times in an embodiment of the present invention.

[0064] Figure 5 Schematic diagram of the evolution of the sand column collapse velocity field and slope line comparison at different times in an embodiment of the present invention.

[0065] Figure 6 This is a schematic diagram of the layout of the indoor impact test device according to an embodiment of the present invention.

[0066] Figure 7 This is a schematic diagram of the velocity field evolution process of sand column particles impacting the baffle according to an embodiment of the present invention.

[0067] Figure 8 This is a schematic diagram showing the comparison of the impact force of a sand column impacting a baffle according to an embodiment of the present invention.

[0068] Figure 9 This is a schematic diagram of the falling process of a 15m high small boulder according to an embodiment of the present invention.

[0069] Figure 10 This is a schematic diagram of the falling process of a small boulder 40m high according to an embodiment of the present invention.

[0070] Figure 11 This is a schematic diagram of the falling process of a 15m high boulder according to an embodiment of the present invention.

[0071] Figure 12 Schematic diagram of a refined vehicle tire model according to an embodiment of the present invention.

[0072] Figure 13 Schematic diagram of the large deformation process of a landslide dam under vehicle cyclic load according to an embodiment of the present invention.

[0073] Figure 14 This is a schematic diagram of the critical transformation of the disaster chain caused by a secondary landslide impacting a landslide dam according to an embodiment of the present invention.

[0074] Figure 15 This is a schematic diagram of the entire process of landslide triggering, induced surge, impact on the landslide dam, and dam instability and collapse according to an embodiment of the present invention. DETAILED DESCRIPTION

[0075] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0076] Example 1

[0077] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0078] The present invention provides a method for simulating large deformation of a landslide dam under extreme working conditions due to instability disaster, comprising the following steps:

[0079] Step 1. Construct a 3D solid model of the landslide dam, a 3D solid model of the terrain, a 3D solid model of the vehicle, a 3D solid model of the rolling stone, a 3D solid model of the water flow, and a secondary landslide model respectively, and discretize them into equidistant particle models; assign basic parameter values to each particle and set the particle type;

[0080] In step 1, multiple real rocks are 3D scanned to establish a rock database, and a 3D solid model of the landslide dam with random positions, random shapes and specified rock content is generated inside the landslide dam. Specifically, the modeling of the rocks inside the landslide dam is carried out, considering the real shape and content of the rocks, and a handheld 3D laser scanner is used to scan multiple real rocks in 3D to establish a rock database, such as Figure 1 (a) As shown. The block stone obtained by 3D scanning is a solid model. The particle sampling algorithm is used to discretize the solid model into a particle model. The particle sampling algorithm process is as follows: set a cube calculation domain, the entire block stone model is included in the cube, set a seed point inside the block stone area, and then set the particle spacing information to continuously generate particles. The block stone STL model boundary is used as the judgment boundary. When the generated particles are inside the block stone STL model boundary, the particles are generated normally. If they are outside the boundary, the generated particles are deleted. Finally, the following can be obtained: Figure 1 (b) shows the particle model. The accuracy of the block stone model can be controlled by adjusting the particle spacing, such as Figure 1 As shown in (c). After the real rock shape is obtained, the real landslide dam model with random position, random shape and specified rock content is generated in the landslide dam. For the random position of the rock, a sphere can be randomly generated in the landslide dam to ensure that the rock is embedded in the sphere position. For the random shape, it can be achieved by randomly extracting the numbered rocks in the rock database. For the specified rock content, the rock content can be calculated by repeatedly generating random positions and random shapes for each rock inside the landslide dam. When the expected rock content is reached, the generation of rock can be stopped, as shown in Figure 2 shown.

[0081] The contour lines or elevation point information of the established three-dimensional terrain is obtained and fitted into a closed solid model, and a three-dimensional terrain solid particle model is generated through a particle filling algorithm. Specifically, the contour lines or elevation point information of the established three-dimensional terrain is required, and this information is imported into the modeling software to fit it into a closed solid model. Then, the three-dimensional terrain solid particle model is generated through the above-mentioned particle filling algorithm and output as a VTK format file for subsequent import into the algorithm program.

[0082] The 3D vehicle, rockfall, secondary landslide, and water flow models were constructed as high-fidelity models based on their actual dimensions. A particle-filling algorithm was then used to generate the vehicle, rockfall, secondary landslide, and water flow models, respectively. Specifically, a high-fidelity model was created in Rhino or CAD based on the actual model dimensions. The particle-filling algorithm was then used to fill the model with solid particle models. The resulting files were then exported as VTK files for easy import into the algorithm system for calculation.

[0083] Step 2. Construct a general constitutive model to characterize the fluidization phase transition behavior of soil;

[0084] The landslide and the dam in the present invention are both soil bodies and use the same constitutive model, but the model parameters have different values. Taking the soil body of the dam as an example, the dam maintains a solid form in the stable stage. When the dam becomes unstable under the action of extreme loads such as the impact of the landslide disaster chain, coupled with the loading of the reservoir water in front of the dam, the dam body will collapse and move downstream, showing the characteristics of fluid motion. After the river is blocked, the dam continues to show solid characteristics. However, after the existing solid constitutive model such as the Drucker-Prager model reaches the yield state, the soil enters the plastic flow state. The strain rate change in the model is always 0, but at this time the soil shows the characteristics of fluidization motion. Its stress changes with strain, that is, the strain rate is not 0. Therefore, traditional solid constitutive models such as the Drucker-Prager model cannot reflect this characteristic. The fluid constitutive model is a rate-dependent constitutive model that can reflect the evolution process of strain rate with stress, but the fluid constitutive model is mainly suitable for high-speed particle flow and cannot model the process of the dam slope becoming unstable and entering yield, that is, it cannot predict the critical sliding start and sliding surface position of the dam slope. Therefore, it is necessary to propose a universal constitutive model for the whole process that is suitable for characterizing the fluidization phase change behavior of the landslide dam soil. The model needs to have the advantages of both solid constitutive models and fluid constitutive models. Therefore, this patent proposes a universal constitutive model that can simulate the evolution of the landslide dam soil in the static solid state, triggered motion state and accumulation solid state. The model parameters can be determined by simple geotechnical tests, and the critical conditions of phase change are determined by the yield condition and strain rate of the soil. Its advantage is that it can automatically realize the smooth conversion of solid and fluid behaviors in the two stages before and after instability, and can predict the fluidization phase change behavior of the landslide dam soil. The total stress format of stress decomposition adopted by the model is as follows:

[0085]

[0086] Where σ total is the total stress, σ solid To characterize the stress before the soil of the landslide dam loses stability, that is, the solid constitutive stress, σ fluid To characterize the stress after the landslide dam soil loses stability, that is, the fluid constitutive stress, α and β represent the vector direction of the stress, p solidis the spherical stress of the solid constitutive law, and the formula 1 / 3σ is used. αβ δ αβ Solve, p critical is the spherical stress when the soil is in the critical state, is the deviatoric stress of the solid constitutive model, s critical is the deviatoric stress when the soil is in a critical state, which can be expressed by the solid constitutive equation Obtain, p fluid is the pressure of the fluid, is the shear stress of the fluid constitutive equation, which can be expressed as Solve, η is the equivalent viscosity, is the absolute value of the shear strain rate of the fluid constitutive part, which can be obtained by Calculated, is the critical shear strain rate of the dam soil, which can be obtained through the ring shear test. When the shear strain rate of the soil exceeds the critical shear strain rate, it will show the characteristics of fluid motion. fluid is the constitutive pressure of the fluid, which can be obtained from the equation of state Find, where c s is the speed of sound, ρ0 is the initial density, γ is the shear strain, ρ i It is the temporary density calculated at each moment. When the landslide dam does not fail, that is, the soil does not yield and the shear strain rate does not exceed the critical shear strain rate of the soil, the condition is satisfied. At this time, the soil of the landslide dam shows solid morphological characteristics; when the landslide dam becomes unstable, that is, the soil yields and the shear strain rate exceeds the critical shear strain rate of the soil, the condition is met. At this time, the soil of the landslide dam exhibits fluid motion characteristics, that is, the stress of the solid constitutive part remains unchanged, and the stress of the fluid part changes with the shear strain rate.

[0087] Step 3. Using the landslide dam soil particles, landslide dam rock particles, vehicle particles, and rolling stone particles as the central particles, particle contact judgment is performed. The deformation behavior of the central particles is simulated based on the constructed universal constitutive model that characterizes the fluidization phase transition behavior of the soil, and the characteristic information of different central particles is coupled and calculated respectively.

[0088] The coupled contact between landslide, water flow, terrain, dam, rockfall and vehicle is as follows: Figure 3 As shown in the figure, in actual engineering, we are more concerned about the safety of the landslide dam itself, so we mainly take the landslide dam as the research object, and mainly consider five types of particles, namely the landslide particle area, denoted as L; the water flow particle area, denoted as W; the terrain particle area is the static boundary, denoted as SB; the dam particle area, denoted as D; the rolling stone, dam internal stone and vehicle particle area belong to the dynamic boundary, all denoted as DB.

[0089] ① With the soil particle i of the landslide dam as the center, the stress between soil particles is calculated using the proposed general constitutive model. The landslide dam contains soil and rock. The soil is calculated using the constitutive model for stress and strain information, and the rock is simulated using the SPH dynamic boundary model. The main contact relationships are: the soil particles of the landslide dam contact with their own soil particles, direct contact with landslide soil particles, contact with the soil particles of the landslide dam and dynamic boundary particles such as their own rock, dam top vehicles, and external rolling stones, contact with the static boundary particles of the terrain, and contact with the soil particles of the landslide dam and reservoir water particles. The control equation of the soil particle i of the landslide dam is as follows, which can be used to calculate the particle acceleration and velocity, and then solve the particle displacement and position, etc.

[0090]

[0091] Where: ρ i is the density of the central particle i; t is the calculation time; m j is the mass of particle j; is the velocity difference between the central particle i and the surrounding particles j in the influence domain, i.e. The direction is β direction; D ij,β is a smooth kernel function, representing the weight value of all particles j in the β direction within the influence domain centered on particle i; x is the position coordinate of the base point, is the displacement of particle i in the β direction; is the velocity gradient of the central particle i, that is, the acceleration of particle i; is the stress tensor of particle i, is the stress tensor of particle j, is the pressure of particle j, is the shear stress of particle j, g α is the acceleration of gravity; α and β represent the vector direction of stress. Stress is a third-order tensor. Both α and β can correspond to the x, y, and z directions. D is the area of soil particles in the landslide dam, L is the area of soil particles in the landslide, W is the area of water particles, DB is the dynamic boundary area of boulders, vehicles on the dam top, and rolling stones, and SB is the static boundary area of particles in the terrain.

[0092] For landslide soil particles, the information calculation is similar to that of landslide dam particles. There are five main contact relationships to consider, namely: contact between landslide soil particles and their own soil particles, contact with landslide dam soil particles, contact with the static boundary of the terrain, contact with the dynamic boundary of the rocks inside the landslide dam, and contact with water flow. The calculation formula is similar to formulas (2) and (3).

[0093] ② For rolling rocks, vehicle loads, and rocks inside landslide dams, the algorithms are relatively similar and are all calculated as movable boundaries. For rock particles, with the landslide dam rock particles as the center, there are five main contact relationships during the movement of the rock: contact between the rock and the landslide soil particles, direct contact between the rock and the landslide soil particles, contact with dynamic boundaries such as other rocks, rolling rocks, and vehicles on the dam top, contact with the static boundary of the terrain, and contact with water particles. Assuming that the rock A is composed of a series of corresponding particles k, the particle information is calculated based on the following formula, which can be used to calculate the particle acceleration and velocity, and then solve the particle displacement, position, etc.

[0094]

[0095]

[0096] Where rock A has mass M A , speed V A , inertia tensor I A , angular velocity Ω A and the center of gravity R A ; Calculate the vector at each time step; D is the landslide soil particle area, L is the landslide soil particle area, W is the water flow particle area, SB is the terrain static boundary particle area, DB is the block stone, dam top vehicle, rolling stone particle dynamic boundary area, f rock,j→k is the force exerted by the rest of the dam's rocks on particle k on rock A, f Vehicle,j→k is the force exerted by the vehicle on the dam top on particle k on the rock A, f debris,j→k is the force exerted by the rolling stone on particle k on stone A, f rock,j→k 、f Vehicle,j→k 、f debris,j→k The following formula can be used for calculation, with f rock,j→k Calculation as an example:

[0097] f rock,j→k =f n,ij +f t,ij (7)

[0098]

[0099] In the formula Normal stiffness coefficient related to elastic modulus, Poisson's ratio and particle radius, is the normal damping constant, e ij is the coefficient of restitution, k t,ij =2 / 7k n,ij . is the tangential stiffness coefficient, γ n,ij =2 / 7γ n,ij is the tangential damping coefficient, δ ij =max(0,(d i +dj ) / 2-|r ij |) is the intrusion distance between particles, which is used to characterize the degree of collision between particles. ij is a unit vector, is the normal deformation rate. The tangential contact force is given by:

[0100]

[0101] The calculation algorithms for vehicles and rolling rocks are similar. Within this patented algorithm framework, vehicle motion is assigned velocity information to calculate the deformation and dynamic response of the landslide dam under the influence of vehicle movement loads. For rolling rocks, an initial velocity and incident direction are required. The rocks then move under the influence of gravity, ultimately impacting the dam body, causing deformation or even instability and collapse.

[0102] Taking vehicle particle i as the center, its main contact relationship is: vehicle particle contacts with landslide soil particles and with landslide block particles. The contact between vehicle and landslide, rolling stone and water flow is not considered. Based on the following formula, particle information can be calculated to calculate particle acceleration and velocity, and then solve particle displacement, position, etc.

[0103]

[0104] Where, ρ k is the density of the central particle k; is the velocity difference between the central particle k and the particles j in the surrounding influence domain, i.e. D kj,β The weight values of all particles j in the influence area centered on particle k in the β direction; is the displacement of particle k in the β direction; rock A has mass M A , speed V A , inertia tensor I A , angular velocity Ω A and the center of gravity R A ;m k is the mass of the central particle k; p k αβ is the pressure of particle k, τ k αβ is the shear stress of particle k, σ j αβ is the stress of particle j, f rock,j→k is the force exerted by the rest of the dam's rocks on particle k on rock A, f Vehicle,j→k is the force exerted by the vehicle on the dam top on particle k on the rock A, f debris,j→k is the force exerted by the rolling stone on particle k on the stone A; r k is the center of gravity of particle k.

[0105] Taking the rolling stone particle k as the center, its main contact relationship is: the rolling stone particle contacts the landslide dam soil particles and contacts the landslide dam block stone particles. The contact between the rolling stone particles and the landslide body, vehicles and water flow is not considered. Therefore, the information of the rolling stone particles can also be calculated according to formulas (11), (12) and (13).

[0106] ④ For water particles, the pressure between water particles is calculated using the SPH weak compressibility algorithm with water particle i as the center. There are five main contact relationships: water particles and themselves, soil particles in the landslide dam, soil particles in the landslide dam, dynamic boundaries of rocks inside the landslide dam, and static boundaries of the terrain. The particle information is calculated based on the following formula, and the particle acceleration and velocity can be calculated, and then the particle displacement and position can be solved:

[0107]

[0108] Where: ρ i is the density of the central particle i; t is the calculation time; m j is the mass of particle j; is the velocity difference between the central particle i and the surrounding particles j in the influence domain, i.e. The direction is β direction; D ij,β is a smooth kernel function, representing the weight value of all particles j in the β direction within the influence domain centered on particle i; x is the position coordinate of the base point, is the displacement of particle i in the β direction; is the velocity gradient of the central particle i, that is, the acceleration of particle i; is the stress tensor of particle i, is the stress tensor of particle j, is the pressure of particle j, which can be obtained through the equation of state, is the shear stress of particle j, which can be expressed by Interpolation is obtained, g α is the acceleration of gravity; α and β represent the vector direction of stress. Stress is a third-order tensor. Both α and β can correspond to the x, y, and z directions. D is the area of soil particles in the landslide dam, L is the area of soil particles in the landslide, W is the area of water particles, DB is the dynamic boundary area of boulders, vehicles on the dam top, and rolling stones, and SB is the static boundary area of particles in the terrain.

[0109] Step 4. Visualize the characteristic information of each central particle obtained by calculation and control it by particle type to achieve material output classification.

[0110] Using smoothed particle fluid dynamics, we calculate the field variables of each particle, such as stress, strain, displacement, velocity, and acceleration. This information is converted into digital text and output as a binary VTK file for visualization. Particle output for different partitions is controlled by particle type, enabling material output classification. Consequently, binary files containing particle information for various types, such as landslides, boulders, and more, can be output. These files can be visualized in general-purpose open-source software such as ParaView.

[0111] Example 1

[0112] In this example, a two-dimensional sand column collapse test was conducted on the unstable accumulation process of the landslide dam. The sand column was 0.2m long and 0.1m high and collapsed naturally under the action of gravity. The particle spacing of the sand column was set to 1mm. The material parameters of the sand column were as follows: density 2040kg / m 3 , elastic modulus E = 5.84 MPa, Poisson's ratio is 0.3, internal friction angle is 21.9°, and cohesion is 0.

[0113] Figure 4 The evolution of the collapse velocity field of the sand column at different times and the comparison of the particle flow contours are given. It can be seen that the numerical simulation results of this study are in good agreement with the experimental results, indicating that the SPH model established by this algorithm can predict the large deformation behavior of granular materials. When the sand column reaches equilibrium, the final accumulation shape is as follows Figure 5 As shown in the figure, according to the cumulative plastic strain distribution, an obvious shear band interface can be observed. It can be seen that the undisturbed area obtained in this study is basically consistent with the experimental results, which further proves the accuracy of the current method.

[0114] Example 2

[0115] This example focuses on the process of a secondary landslide directly impacting a landslide dam, and compares the results of an indoor impact test to verify the reliability of the model in calculating the impact response of the landslide evolution process. Figure 6 The indoor impact test device used is shown in Figure 1, where (a) is a real-life view of the test device and (b) is a schematic diagram of the geometric parameters of the test device. The inclined chute has an inclination angle of 45°, is 0.5m long and 0.3m wide, and the distance from the front of the sand column to the wall is 1.8m. Initially, after the wooden box door is opened, the fine sand moves along the chute under the action of gravity. A measuring instrument that can record the impact force value is installed at the bottom of the chute. After the fine sand collides with the measuring instrument, it will gradually come to rest. The density of fine sand is 1379kg / m 3 , the internal friction angle is 35°, and the cohesion is 0. A landslide impact baffle model is established, and the particle spacing is set to 0.01m.

[0116] Figure 7The velocity field evolution process of the sand column impacting the baffle at different times is given. After being released, the sand column evolves downward, then hits the rigid baffle and accumulates in front of the baffle. When the sand pile reaches the top of the baffle, part of the sand overflows and flows out. Figure 4 The results show that the simulation results are similar to the experimental phenomena. Figure 8 This figure compares the impact force time history curves obtained from the indoor test and numerical simulation. Before the sand column collides with the baffle, the impact force remains zero. As the sand and baffle collide at T = 0.71 s, the sand accumulates in front of the baffle, causing the impact force on the baffle to gradually increase and reach a peak. Subsequently, the impact force on the baffle decreases slightly due to the overflow of the sand. Figure 8 It shows that the time point of the landslide impacting the baffle calculated in this study is basically consistent with the test. For the peak impact force, the peak impact force on the baffle in the test is 188.6N, and the peak impact force obtained in this study is 188.2N, which is slightly lower than the test value. The relative error of the peak impact force is 0.2%. Overall, it can be seen that the impact force obtained in this study is in good agreement with the test results.

[0117] Example 3

[0118] This embodiment considers different rockfall volumes and different rockfall initial heights to calculate the large deformation process of the dam slope caused by rockfall impact. The figure shows the plastic strain.

[0119] Figure 9 The dynamic process of a rolling stone with a volume of 0.5m*0.5m*0.5m impacting the dam at a height of 15m is given. It can be seen that the top of the landslide dam shows local damage, the plastic zone of the dam slope increases slightly, and the dam body remains basically stable.

[0120] Figure 10 The dynamic process of a rockfall with a volume of 0.5m*0.5m*0.5m impacting the dam at a height of 40m is given. It can be seen that local damage occurs on the crest of the landslide dam, and the range of the plastic zone on the dam slope increases significantly compared with the 15m working condition. The plastic zone gradually penetrates over time and undergoes large deformation, but the deformation rate is slow. This indicates that the higher the initial height of the rockfall, the greater the kinetic energy when it falls to the dam crest, the more severe the local damage to the dam crest, and the larger the range of the plastic zone.

[0121] Figure 11 The dynamic process of a rockfall of 1.5m*1.5m*1.5m impacting a dam at a height of 15m is presented. It shows extensive damage to the crest of the landslide dam, and the plastic zone of the dam slope is continuous, indicating overall instability. The dam slope cannot maintain stability at this point. The instability of the landslide dam then develops into a chain of flood disasters. This demonstrates that the patented algorithm can predict the transformation of this chain of disasters, such as rockfall loads, that can lead to landslide dam instability, failure, or further river blockage. This provides a tool for risk assessment and early warning of landslide instability.

[0122] Example 4

[0123] This embodiment performs high-fidelity modeling on different emergency response vehicles, such as Figure 12 shown. Figure 13 The distribution of plastic zone of landslide dam slope under vehicle cyclic load is given. Figure 13 It shows that as the number of vehicle load cycles increases, the plastic zone of the dam slope increases significantly, and the landslide dam may become unstable. This shows that the patented algorithm can predict the deformation and destruction process of the landslide dam under complex loads such as vehicles.

[0124] Example 5

[0125] This example is a calculation of the disaster chain transformation process caused by the impact of a secondary landslide on a landslide dam. A particle model of the secondary landslide, landslide dam, and terrain boundary is established. Figure 14 It can be seen that, on the one hand, this case shows that the general constitutive function adopted by the algorithm of this patent can better calculate the entire process of landslide initiation-movement-accumulation, and reasonably characterize the interaction between the landslide and the terrain boundary; on the other hand, after the secondary landslide hits the landslide dam, it will cause the volume of the landslide dam to increase, and the height of the landslide dam to increase, making the landslide dam less likely to fail, affecting the critical transformation process of the landslide dam disaster chain, indicating that the algorithm of this patent can simultaneously calculate and identify the critical transformation process of the disaster chain of landslide blocking the river to form a landslide dam.

[0126] Example 6

[0127] This example simulates the entire process of landslide-induced surge impact-induced landslide dam instability and large deformation. Figure 15 The whole process of landslide triggering, induced surge, impact on landslide dam and dam failure is shown in the figure. The landslide and dam are simulated using the universal constitutive model of this patent. Figure 15 (a) to (e) show that this algorithm can reasonably characterize the coupled contact relationship between landslide soil, terrain, water flow, and landslide dam. From the movement behavior of the landslide body, it can be seen that this patent can predict the entire process of the landslide soil from the triggered quasi-static state to the moving state and then to the accumulated solid state. From the movement behavior of the water flow, it can be seen that this patent can better capture the fluid-solid coupling behavior between the landslide-water body-landslide dam. From the instability and failure behavior of the landslide dam, it can be seen that this patent can realize the refined numerical simulation of the large deformation of the instability disaster of the landslide dam under extreme loads such as the impact of the landslide disaster chain, and realize the accurate prediction of the plastic failure zone of the landslide dam.

[0128] Example 7

[0129] This embodiment provides a system for simulating large deformation of a landslide dam under extreme working conditions due to instability disasters, including:

[0130] Particle model construction module: It is used to construct the 3D solid model of the landslide dam, the 3D solid model of the terrain, the 3D solid model of the vehicle, the 3D solid model of the rolling stone, the solid model of the water flow, and the secondary landslide body, and discretize them into equidistant particle models; assign basic parameter values to each particle and set the particle type;

[0131] Constitutive model building module: It is used to build a general constitutive model to characterize the fluidization phase change behavior of soil;

[0132] Coupling calculation module: It is used to determine particle contact using landslide dam soil particles, landslide dam block particles, vehicle particles, and rolling stone particles as central particles. It simulates the deformation behavior of central particles based on the constructed universal constitutive model that characterizes the fluidization phase change behavior of soil, and performs coupled calculations on the characteristic information of different central particles.

[0133] Visualization output module: It is used to visualize the characteristic information of each central particle obtained by calculation, and control it by particle type to realize material output classification.

[0134] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0135] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if such changes and modifications of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such changes and modifications.

[0136] Other parts not described in detail are prior art.

Claims

1. A method for simulating large deformation of a landslide dam under extreme working conditions, characterized by: The steps include: Step 1. Construct a 3D solid model of the landslide dam, a 3D solid model of the terrain, a 3D solid model of the vehicle, a 3D solid model of the rolling stone, a 3D solid model of the water flow, and a secondary landslide model respectively, and discretize them into equidistant particle models; assign basic parameter values to each particle and set the particle type; Step 2. Construct a general constitutive model to characterize the fluidization phase transition behavior of soil. The general constitutive model to characterize the fluidization phase transition behavior of soil is: in, is the total stress; is the spherical stress of the solid constitutive model; is a piecewise function, and Represents the stress vector direction, when hour The value is 1, otherwise it is 0; is the deviatoric stress of the solid constitutive model; is the constitutive pressure of the fluid; is the constitutive shear stress of the fluid; To characterize the stress before the landslide dam soil loses stability, that is, the solid constitutive stress, its value is ; is the stress intensity value when the material is in the critical state, which can be obtained through geotechnical engineering tests. Its value is ; is the real-time shear strain rate of the landslide dam soil; is the critical shear strain rate of the landslide dam soil, which can be obtained through geotechnical engineering tests; is the spherical stress when the soil is in the critical state, is the shear stress when the soil is in a critical state; Step 3. Take the landslide dam soil particles, landslide dam block particles, vehicle particles, and rolling stone particles as the central particles, perform particle contact judgment, simulate the deformation behavior of the central particles based on the constructed universal constitutive model for characterizing the fluidization phase transition behavior of the soil, and couple and calculate the characteristic information of different central particles. The deformation behavior of the central particles simulated based on the constructed universal constitutive model for characterizing the fluidization phase transition behavior of the soil includes: Taking the dam soil particle, landslide soil particle or water particle as the central particle i, the control equation is as follows: Where: is the density of the central particle i; To calculate time; is the mass of particle j; is the velocity difference between the central particle i and the surrounding particles j in the influence domain, i.e. , the direction is direction; is a smooth kernel function, representing the influence of all particles j in the domain centered on particle i. The weight value in the direction; are the position coordinates of the base point, For particle i displacement in direction; is the velocity gradient of the central particle i, that is, the acceleration of particle i; is the stress tensor of particle i, is the stress tensor of particle j, is the pressure of particle j, is the shear stress of particle j, is the acceleration due to gravity; and Represents the vector direction of stress, which is a third-order tensor. and All of them can be taken in the x, y, and z directions; D is the landslide soil particle area, L is the landslide soil particle area, W is the water flow particle area, DB is the dynamic boundary area of boulders, dam top vehicles, and rolling stones, and SB is the terrain static boundary particle area; Taking the rock particle of the landslide dam as the central particle k, the control equation is as follows: Where, is the density of the central particle k; is the velocity difference between the central particle k and the particles j in the surrounding influence domain, i.e. ; All particles j in the influence area centered on particle k are The weight value in the direction; For particle k displacement in the direction; rock A has mass ,speed , inertia tensor , angular velocity and center of gravity ; is the mass of the central particle k; is the pressure of particle k, is the shear stress of particle k, is the stress of particle j, is the force exerted by the rest of the dam's rocks on particle k on rock A, is the force exerted by the vehicle on the dam top on particle k on the rock A, is the force exerted by the rolling stone on particle k on the stone block A; is the center of gravity of particle k; Vehicle particles or rolling stone particles As the central particle, the control equation is as follows: Where, Central particle density; It is the central particle The speed difference with the particle j in the surrounding influence area is ; Therefore All particles j in the influence area centered on the particle The weight value in the direction; For particles exist displacement in direction; Central particle quality; For particles pressure, For particles The shear stress, The rest of the rocks in the dam are on the rock A. The force exerted by the particles, for The particle's center of gravity; Step 4. Visualize the characteristic information of each central particle obtained by calculation and control it by particle type to achieve material output classification.

2. The method for simulating large deformation of a landslide dam under extreme working conditions according to claim 1, characterized in that: In step 1, a plurality of real rocks are three-dimensionally scanned to establish a rock database, and a three-dimensional solid model of the landslide dam with random positions, random shapes and specified rock content is generated within the landslide dam; Obtain the contour lines or elevation point information of the established three-dimensional terrain and fit it into a closed entity model, and generate a three-dimensional terrain entity particle model through a particle filling algorithm; The vehicle 3D solid model, rolling stone 3D solid model, secondary landslide body model and water flow solid model are built into high-fidelity models according to the actual model size and the particle filling algorithm is used to generate the vehicle 3D solid particle model, rolling stone 3D solid particle model, secondary landslide body particle model and water flow solid particle model respectively.

3. The method for simulating large deformation of a landslide dam under extreme working conditions according to claim 1, characterized in that: The step 1 includes landslide soil particles, water flow particles, terrain particles, landslide dam soil particles and dynamic boundary particles; the dynamic boundary particles include rolling stone particles, landslide dam block stone particles and vehicle particles.

4. The method for simulating large deformation of a landslide dam under extreme working conditions according to claim 3, characterized in that: In step 1, the basic parameters of the landslide soil particles are set to include density, internal friction angle, cohesion, elastic modulus, Poisson's ratio, and friction coefficient; The basic parameters set for water flow particles include: density, viscosity; The basic parameters set for terrain particles include: density, elastic modulus, Poisson's ratio, and friction coefficient; The basic parameters set for the soil particles of the landslide dam include density, internal friction angle, cohesion, elastic modulus, Poisson's ratio, and friction coefficient; The basic parameters set for dynamic boundary particles include density, elastic modulus, Poisson's ratio, and friction coefficient.

5. The method for simulating large deformation of a landslide dam under extreme working conditions according to claim 1, characterized in that: The particle contact determination in step 3 includes: All particle contact types are judged. If the particle radius is r, the particle's influence domain is 2r. That is, contact calculation is performed when the distance between two particles does not exceed 2r, and the contact effect between the two particles is calculated.

6. The method for simulating large deformation of a landslide dam under extreme working conditions according to claim 1, characterized in that: 、 、 The following formula can be used for calculation: Where, is the normal stiffness coefficient related to the elastic modulus, Poisson's ratio and particle radius, is the normal damping constant, is the coefficient of restitution, is the tangential stiffness coefficient, is the tangential damping coefficient, is the intrusion distance between particles, which is used to characterize the degree of collision between particles. is a unit vector, is the normal deformation rate, and the tangential contact force is given by: 。 7. The method for simulating large deformation of a landslide dam under extreme working conditions according to claim 1, characterized in that: The step 4 includes: calculating the field variable information of each particle through the smooth particle fluid dynamics method, and the obtained information is digital text information, which is converted into a binary VTK file output for visualization. The particle output of different partitions is controlled by the particle type, and material output classification can be realized.

8. A system for simulating large deformation of landslide dam instability disaster under extreme working conditions, characterized by: include: Particle model construction module: It is used to construct the 3D solid model of the landslide dam, the 3D solid model of the terrain, the 3D solid model of the vehicle, the 3D solid model of the rolling stone, the solid model of the water flow, and the secondary landslide body, and discretize them into equidistant particle models; assign basic parameter values to each particle and set the particle type; Constitutive model building module: It is used to build a general constitutive model to characterize the fluidization phase change behavior of soil; Coupling calculation module: It is used to determine particle contact using landslide dam soil particles, landslide dam block particles, vehicle particles, and rolling stone particles as central particles. It simulates the deformation behavior of central particles based on the constructed universal constitutive model that characterizes the fluidization phase change behavior of soil, and performs coupled calculations on the characteristic information of different central particles. Visualization output module: It is used to visualize the characteristic information of each central particle obtained by calculation, and control it by particle type to achieve material output classification; The system for simulating large deformation caused by instability of a landslide dam under extreme working conditions is used to execute the steps of the method for simulating large deformation caused by instability of a landslide dam under extreme working conditions described in any one of claims 1 to 7.

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