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54 results about "Material point method" patented technology

The material point method (MPM) is a numerical technique used to simulate the behavior of solids, liquids, gases, and any other continuum material. Especially, it is a robust spatial discretization method for simulating multi-phase (solid-fluid-gas) interactions. In the MPM, a continuum body is described by a number of small Lagrangian elements referred to as 'material points'. These material points are surrounded by a background mesh/grid that is used only to calculate gradient terms such as the deformation gradient. Unlike other mesh-based methods like the finite element method, finite volume method or finite difference method, the MPM is not a mesh based method and is instead categorized as a meshless/meshfree or continuum-based particle method, examples of which are smoothed particle hydrodynamics and peridynamics. Despite the presence of a background mesh, the MPM does not encounter the drawbacks of mesh-based methods (high deformation tangling, advection errors etc.) which makes it a promising and powerful tool in computational mechanics.

Explicit substance point method for analyzing large deformation power of weak compressible substance

The invention belongs to the technical field of weak compressible large deformation of soft materials, provides a dynamic analysis explicit substance point method for large deformation of weak compressible materials, and provides a brand new numerical calculation method for large deformation research of the weak compressible materials. According to the method, a weak-form control equation is discretized in a total Lagrangian substance point method framework, and challenges caused by grid distortion when a traditional method is used for solving a large deformation problem are avoided. Besides, the invention provides a volume self-locking processing technology based on an F-bar method, the problem of volume locking of the weakly compressible substance in numerical simulation can be simply, conveniently and effectively solved, and the volume self-locking processing technology can be conveniently embedded into an existing substance point method program. Meanwhile, a construction method of a smooth kernel interpolation function is developed, and the problem that the solving precision of a traditional substance point method in a boundary region is reduced can be effectively solved. According to the method, the problem of large deformation of the weak compressible material can be solved in a stable and efficient manner, and a new technical path is provided for research and application in related fields.
Owner:DALIAN UNIV OF TECH

Landslide stability assessment method and system based on combination of material point method and transfer coefficient method

The invention discloses a landslide stability evaluation method and system combining a material point method and a transfer coefficient method, and the method comprises the steps: building a three-dimensional material point model for a landslide body based on the material point method, and obtaining the stress field distribution, deformation characteristics and fluid-solid coupling effect of the landslide body; dividing the landslide mass into a plurality of block areas, and determining the block area and the position of each material point; constructing a stress transfer matrix taking the positions and physical information of the material points as elements, calculating normal stress in the vertical direction between the block areas of the landslide mass and tangential stress parallel to the contact surface between the block areas based on the stress transfer matrix, and calculating a real-time stability coefficient; based on the displacement, the pore water pressure and stress and the real-time stability coefficient, the dynamic safety coefficient of the landslide mass is calculated, and stability evaluation is conducted on the landslide mass. Through combination of the material point method and the transfer coefficient method, the mechanical behavior and the material propagation process of the landslide mass are considered, and the evaluation precision of the landslide stability is improved.
Owner:CHANGAN UNIV

Numerical model construction method of open pile soil plug effect based on material point method

The invention discloses a material point method-based open pile soil plug effect numerical model construction method, which comprises the following steps: carrying out an indoor semi-model tank test by adopting standard sandy soil, and recording data of friction resistance of the inner side and the outer side of a pile, soil stress, soil plug height and a displacement field in a pile sinking process; a geometric model is established based on an indoor model test, numerical simulation is performed by adopting a two-dimensional axisymmetric substance point method in combination with a grid encryption strategy, and data of friction resistance of the inner side and the outer side of a pile, a soil stress field, the soil plug height and a displacement field are obtained; performing comparative analysis on the indoor test data and the numerical simulation result, and if an error meets a preset requirement, confirming the validity of the numerical model; and if the comparison result does not meet the requirement, optimizing the numerical model. The soil plug effect in the pile sinking process can be effectively simulated, the response of the open pile to a stress field and a displacement field of a surrounding soil body can be deeply researched, and a more accurate basis can be provided for structural design and bearing capacity calculation of the open pile.
Owner:ZHEJIANG UNIV

MPM method-based landslide geological disaster deduction method and system

The invention discloses a landslide geological disaster deduction method and system based on an MPM method, and the method comprises the steps: collecting the multi-source data of a disaster scene, and synchronously constructing a digital twinborn model; a qualitative and quantitative two-stage inversion calibration model is adopted; a qualitative layer combines a monitored displacement direction and a deformation mode, and preliminarily inverts key parameters such as slip band cohesive force and an internal friction angle; the quantitative layer comparison model calculates the actual deformation range, collapse position and displacement, and parameters are optimized to match the actual landslide state; in landslide long-term evolution deduction, a rock-soil body aging characteristic model is embedded, an exponential function is used for describing annual scale parameter deterioration, prediction is divided into continuous analysis steps, MPM calculation is carried out based on a material point method, full-cycle simulation from the current year to the future years is completed, and deformation range, displacement and outburst risk results are output. And reliable decision support is provided for disaster prevention and reduction.
Owner:INST OF ROCK & SOIL MECHANICS CHINESE ACAD OF SCI +2

Dynamic impact / contact tough metal fracture analysis explicit cohesion phase field material point method

The invention belongs to the technical field of ductile metal fracture analysis, provides an explicit cohesion phase field material point method, and provides a brand new numerical calculation method for metal dynamic fracture damage research. In the method, aiming at the problems of large deformation and high-speed impact in ductile metal spallation and penetration failure, a cohesion phase field material point method and a marble compliant contact algorithm are innovatively provided. The cohesion phase field model can well describe the damage softening and fracture behaviors of the tough metal. The marble compliant contact algorithm effectively suppresses the problems that the speed of impacting the contact surface is over-oscillated and the normal vector outside the contact surface is difficult to calculate. Then, a control equation of dynamic fracture of the ductile metal is deduced through a Lagrange equation, and the control equation of the coupling displacement and cohesion phase field model is discretized in a material point method framework; and finally, a phase field-displacement field interlaced solution strategy is adopted to stably and efficiently solve the problems of contact, large deformation and other strong nonlinear large-scale ductile fracture damage.
Owner:DALIAN UNIV OF TECH

Virtual reality level simulation method based on material point method and gridding surface reconstruction

The invention discloses a virtual reality level simulation method based on a material point method and gridding surface reconstruction, and belongs to the crossing field of computer graphics, physical simulation and virtual reality technologies. The method comprises the following steps: S1, classifying and storing position coordinates of material points according to material numbers of the material points, and traversing the coordinates to obtain a boundary of a bounding box of the material points; s2, selecting a grid size and a boundary extension distance for reconstructing the surface in a self-defined manner, and generating a grid; s3, selecting a Gaussian function to calculate the contribution of each substance point to the overall substance point density field, and obtaining parameters; s4, calculating the contribution of each substance point to the overall substance point density field, and performing accumulation to obtain the overall substance point density field; and S5, obtaining a contour surface of the overall material point density field, and exporting the contour surface as a rendering engine general three-dimensional model to obtain a simulation visual effect. According to the method, the problems that in the prior art, tens of millions of substance points cannot be processed, reconstruction parameters are difficult to select, and connection with a high-end rendering engine is not smooth can be solved, and the virtual reality level simulation visual effect is achieved.
Owner:DALIAN UNIV OF TECH

Topological optimization method, device and equipment for material distribution based on particle flow

The invention discloses a topological optimization method, device and equipment for material distribution based on particle flow, and relates to the technical field of material structure optimization. According to the method, isogeometric analysis is introduced into the material point method in topological optimization of material distribution, the isogeometric material point method is provided, consistency between geometric modeling and numerical analysis is achieved through a unified primary function of isogeometric analysis, benefit from high-order continuity of the primary function of isogeometric analysis, and the method has the advantages that the method is simple and convenient to implement. The introduction of isogeometric analysis can effectively eliminate and suppress numerical artifacts in topological optimization and unit cross instability in a traditional substance point method. According to the isogeometric material point method, movable particles of material distribution in a physical domain serve as design variables, a set of particle-grid physical information and sensitivity transmission model is established in combination with Lagrange-Euler mixed description, corresponding accurate geometric topology is output while particle evolution is achieved, and the method has the advantages of being high in accuracy and high in reliability. And the accuracy and the flexibility of topological optimization of the material distribution structure are remarkably improved.
Owner:HUAZHONG UNIV OF SCI & TECH

A method for analyzing large deformations of saturated soil and structures based on the semi-implicit material point method

ActiveCN120197461BGeometric CADDesign optimisation/simulationClassical mechanicsPressure poisson equation
This invention relates to a method for analyzing large deformations of saturated soil and structures based on a semi-implicit material point method, comprising: decoupling pore pressure and motion variables using an incremental step method; introducing a penalty function for an enhanced frictional contact algorithm; introducing an artificial compressibility parameter into the pressure Poisson equation; employing the B-bar technique to reduce volume lock-in effects; using an affine particle cell method; modifying the calculation formula for axisymmetric problems, considering volume integrals and gradient evaluation in cylindrical coordinates; and conducting verification. The beneficial effects of this invention are: by employing an incremental step method, artificial fluid compressibility, and the B-bar technique, this invention avoids numerical instability caused by coupling problems in traditional methods, ensures the convergence of the simulation process, and avoids non-physical stress oscillations.
Owner:温州市鹿城区城市建设中心(温州市鹿城区市政公用建设中心) +1

A method for simulating whole process of large deformation of earthquake landslide based on grid isolation technology

The application discloses a large deformation whole process simulation method of earthquake landslide based on a grid isolation technology and relates to the technical field of geotechnical engineering.The application constructs a separated background grid and a multi-medium model containing a safety isolation zone based on a second-order convection particle domain interpolation material point method, carries out dynamic analysis on the earthquake landslide by using a strain-driven hardening-softening coupling constitutive mechanism, realizes flexible input of the earthquake wave at the isolation zone and anti-drifting of the base, and can accurately simulate the complete evolution process of the landslide from undrained shear cracking to large deformation friction accumulation.The application effectively eliminates wave reflection interference of the dynamic boundary and numerical drift of long-time integration, realizes real physical reproduction of the whole process of the earthquake landslide from cracking to friction accumulation, makes calculation of large deformation and permanent displacement of the slope under the action of the earthquake more accurate and stable, and lays a foundation for prediction and evaluation of the whole process of the landslide disaster evolution.
Owner:SOUTHWEST JIAOTONG UNIV

A solid-liquid coupling simulation method with surface tension effect based on the material point method

The present invention discloses a solid-liquid coupling simulation method with surface tension effect based on the material point method, belonging to the fields of computer graphics and physics-based simulation. The system used in the simulation method includes solid model modeling, fluid model modeling, Level Set implicit surface construction, Marching Cubes display surface construction, surface particle resampling, and collision detection. The system simulates fluids and solids on the basis of the material point method, constructs Level Set to resample fluid surface particles, and adds surface tension to the fluid using the CSF model. Different background grids are used to simulate fluids and solids respectively to solve the inherent adhesion phenomenon during MPM solid-liquid coupling and achieve the slip contact effect during solid-liquid coupling. Finally, the coupling phenomenon of incompressible fluid with surface tension effect and nonlinear elastic solid is realized.
Owner:YANSHAN UNIV

Cuttable interactive soft body simulation method and system based on gpu accelerated material point method

The application provides a cuttable interactive soft body simulation method and system based on a GPU accelerated material point method, and belongs to the field of computer graphics physics simulation, and comprises the following steps: S1: sampling and initializing a three-dimensional soft body model to be simulated and a rigid body model interacting with the three-dimensional soft body model; S2: constructing an initial GPU secondary sparse acceleration structure Ggrid based on a virtual scene to be simulated; S3: extending the Ggrid; S4: updating the state of the rigid body model and constructing a rigid body cutting field of the Ggrid; S5: solving a physical explicit integration of the three-dimensional soft body model to be simulated in parallel based on the Ggrid and the rigid body cutting field, and obtaining the position of a Lagrange particle at the next time; and S6: at the last iteration of each frame, reconstructing a surface triangular mesh mesh of the Lagrange particle cluster in real time based on the Ggrid, and smoothing the surface triangular mesh mesh. The method realizes multi-material soft body deformation, cutting interaction, fragmentation and real-time surface reconstruction.
Owner:BEIHANG UNIV

Earthquake landslide large deformation whole process simulation method based on grid isolation technology

ActiveCN122020818AAchieve real physical reproductionEliminate wave reflection interferenceGeometric CADDesign optimisation/simulationLandslideStructural engineering
The invention discloses an earthquake landslide large deformation whole process simulation method based on a grid isolation technology, and relates to the technical field of geotechnical engineering. According to the method, a separated background grid containing a safety isolation belt and a multi-medium model are constructed based on a second-order convective particle domain interpolation material point method, and dynamic analysis is performed on seismic landslide by using a strain-driven soft and hard coupling constitutive mechanism, so that flexible input of seismic waves at the isolation belt and drifting prevention of a substrate are realized; and the complete evolution process of the landslide from undrained shear crack initiation to large-deformation friction accumulation can be accurately simulated. According to the method, wave reflection interference of a dynamic boundary and numerical drift of long-lasting integral are effectively eliminated, and real physical reproduction of the whole process of seismic landslide from crack initiation to friction accumulation is realized; therefore, calculation of large deformation and permanent displacement of the side slope under the earthquake action is more accurate and stable, and a foundation is laid for prediction and evaluation of the whole evolution process of landslide disasters.
Owner:SOUTHWEST JIAOTONG UNIV

A three-dimensional terrain geological modeling method and device based on a material point method simulation

The application provides a three-dimensional terrain geological modeling method and device based on material point method simulation, and relates to the technical field of geotechnical engineering numerical simulation, and comprises the following steps: S1, extracting elevation data of a three-dimensional terrain geological region model; S2, converting the elevation data into three different type model component data and processing; S3, based on the generated model component data, discretizing the model into material points to generate a material point model; S4, importing the generated material point model into a material point method calculation program to perform material point method simulation, and obtaining large deformation of the geology according to the material point method simulation; the application effectively solves the problem of large deformation simulation modeling caused by complex and diverse terrain and landform, is efficient, stable, simple and feasible, significantly improves the modeling efficiency of the material point method and the quality of the generated material point model, and effectively promotes the application of the material point method simulation in the field of geotechnological engineering numerical simulation.
Owner:SHENZHEN UNIV

Step-by-step decomposition-space mapping method for generating 3d material parameter random field of material points

The application provides a step-by-step decomposition-space mapping three-dimensional material point material parameter random field generation method, and belongs to the technical field of water conservancy and hydropower. First, a three-dimensional geometric model of a structure is established according to engineering geological data, high-precision mesh division is carried out, each mesh is converted into a material point carrying mass and volume, and a material point model is obtained. Second, a background mesh element is determined, and a background mesh covering the space occupied by the entire structure is generated. Third, a correlation function reflecting the material parameter properties is selected, a step-by-step decomposition method is used, and a material parameter random field on the background mesh element is generated. Finally, the value of the material parameter of the material point model is determined through a space mapping technology, and a three-dimensional material point material parameter random field is generated. The application is based on the material point method, and realizes the generation of a three-dimensional random field of a geotechnical engineering material parameter through the joint application of a step-by-step decomposition-space mapping technology, thereby providing technical support for the simulation of large deformation of a geotechnical engineering considering spatial variability.
Owner:DALIAN UNIV OF TECH

A Fluid-Structure Interaction Simulation Method for Immersed Boundaries Based on the Material Point Method and Position Dynamics

A fluid-structure interaction (FSI) simulation method for submerged boundaries based on the material point method and positional dynamics includes: a) solving for the solid state and calculating the Lagrangian elastic force of the solid; b) transferring the elastic force of the solid Lagrangian mesh vertices to the Eulerian background mesh; c) solving the Navier-Stokes fluid control equations and continuity equations on the Eulerian background mesh, feeding back the updated mesh flow field information to the particles, and updating the particle state synchronously; d) using a mapping matrix to map the positions of solid particles back to the vertices of the solid Lagrangian mesh, saving the vertex position data and fluid particle data for rendering output. This invention, through the above-mentioned hybrid Lagrangian-Eulerian perspective coupling solution, can realistically simulate the bidirectional coupling between solids of different materials and complex fluids, significantly improving the physical realism and visual fidelity of the simulation scene.
Owner:EAST CHINA NORMAL UNIV

A virtual reality level simulation method based on material point method and gridding surface reconstruction

A virtual reality level simulation method based on material point method and gridding surface reconstruction belongs to the cross field of computer graphics, physical simulation and virtual reality technology. The steps are as follows: S1, storing the material point position coordinates according to the material point material number, and obtaining the bounding box boundary of the material point by traversing the coordinates; S2, defining and selecting the grid size and boundary extension distance for reconstructing the surface, and generating the grid; S3, selecting a Gaussian function to calculate the contribution of each material point to the overall material point density field, and obtaining the parameters; S4, calculating the contribution of each material point to the overall material point density field, and accumulating to obtain the overall material point density field; S5, obtaining the isosurface of the overall material point density field, and exporting it as a general three-dimensional model of a rendering engine to obtain a simulation visual effect. The method can solve the problems that the prior art cannot process ten million material points, the reconstruction parameter selection is difficult, and the connection with a high-end rendering engine is not smooth, and realizes a virtual reality level simulation visual effect.
Owner:DALIAN UNIV OF TECH

An intelligent prediction method for landslide disaster risk probability based on two-phase material point method

The present invention belongs to the technical field of geological disaster monitoring and early warning, specifically relating to an intelligent prediction method for landslide disaster risk probability based on the two-phase material point method. By treating parameters such as rock and soil properties and rainfall intensity as statistically correlated multivariate random variables, the two-phase material point method is used to numerically simulate the entire process of rainfall-induced landslide disasters. The probability distribution of response quantities such as sliding distance, collapse range, and sliding body volume is then obtained, and the risk probability is predicted based on the characteristics of the hazard-bearing body. Random samples are extracted based on the prior distribution of each parameter variable as input data sets, and the response quantity samples obtained by simulation calculations are used as output data sets. The method is trained using an XGBoost model to construct a proxy model for the two-phase material point method. Bayesian probabilistic inversion is used to perform parameter inversion on slope monitoring data, dynamically updating the probability distribution of each model response quantity. Based on the response quantity distribution, the risk probability is predicted in real time. This method not only has clear physical meaning but also improves prediction efficiency and accuracy.
Owner:CHONGQING MUNICIPAL BUREAU OF GEOLOGICAL & MINERAL EXPLORATION & DEV +1

Geographical reconstruction-considered landslide motion simulation method

The invention provides a landslide motion simulation method considering terrain reconstruction, and solves the logic contradiction of the traditional method for simulating the initial motion by using the landslide terrain. The method comprises the following steps: acquiring high-precision terrain, volume, geological parameters and rainfall data after landslide; the landslide terrain is used as a starting point, and the landslide terrain is restored through volume conservation, reasonable flow direction and flow and rock-soil body strength adaptive constraint iterative correction; based on a reconstructed terrain, coupling rainfall infiltration, a pore water pressure evolution model and a material point method, a landslide movement process is positively simulated, and information such as speed, acceleration and accumulation depth is inversed. According to the invention, initial condition errors are eliminated from the source, the simulation precision is high, and a scientific tool is provided for landslide mechanism research and disaster prevention and control.
Owner:HEBEI UNIV OF TECH

Boundary self-adaption and surface reconstruction method and device based on material point method

The invention provides a boundary self-adaption and surface reconstruction method and device based on a material point method, and relates to the technical field of computer graphics. The method comprises the following steps: splitting original particles according to user control parameters to obtain subdivided particles, and performing position reconstruction on the subdivided particles; information carried by the original particles and the subdivided particles is transmitted to the grid; stress on the grids is calculated according to the information; and returning a stress calculation result to the original particles, and carrying out particle advection. The multi-scale particle interpolation technology provided by the invention ensures the stable interaction of particles with different scales. Multi-scale grid transmission is provided, it is guaranteed that particles of different scales can be mutually influenced through the grids, and the requirement of a user for simulation precision is met by adjusting the sizes of the grids. According to the provided boundary surface particle reconstruction scheme, the problems of unsmooth surface and the like caused by uneven distribution of subdivided particles can be avoided, and a more accurate simulation effect is achieved.
Owner:SHUNDE INNOVATION SCHOOL UNIVERSITY OF SCIENCE & TECHNOLOGY BEIJING

Method and apparatus for assessing highway resilience under rainfall landslide conditions

This invention relates to a method and equipment for probabilistic assessment of highway resilience under rainfall-induced landslide conditions, comprising the following steps: S1, calibrating a random rainfall model and the probability density distribution function of soil and rock parameters; S2, numerically simulating the sliding distance of the slope using a two-stage analysis of the finite element method and the material point method, and constructing a sample library of highway residual functions; S3, constructing a two-stage predictive proxy model for highway residual functions; S4, randomly sampling soil and rock parameters and rainfall events, and predicting highway residual functions based on the two-stage predictive proxy model; S5, constructing a probabilistic ladder recovery model for highway functions based on a decision tree, randomly sampling the recovery patterns of the highway after different landslide events, and calculating the highway resilience index based on the predicted value of the highway residual functions; S6, repeating step S5 multiple times to solve for the mean and standard deviation of the highway resilience index. Compared with existing technologies, this invention can achieve rapid and accurate assessment of the resilience level of slope highways.
Owner:TONGJI UNIV

Fast gauss splash physics simulation method and related apparatus

The application discloses a fast Gaussian splash physical simulation method and related equipment, and relates to the technical field of physical model simulation generation. The method comprises the following steps: segmenting each object in a static three-dimensional Gaussian scene; constructing an occupancy field, and then dividing corresponding points into the interior of the object according to an occupancy probability; filling the points in the interior of the object by using a Monte Carlo importance probability sampling method; acquiring physical parameters of the object for simulation of a material point method according to a text description by using a large language model; and generating simulation results of each object according to the physical parameters. The application firstly segments an input static three-dimensional Gaussian scene, then obtains a preliminary filling result by using an occupancy field, and then fills a complex structure according to Gaussian importance by using the Monte Carlo importance probability sampling method proposed in the application. The text physical optimization based on the large language model proposed in the application can quickly optimize and determine the physical parameters of the object, and obtain stable simulation results.
Owner:SUN YAT SEN UNIV

Thermal-mechanical coupling frozen soil deformation rapid prediction method based on material point method

The invention relates to the technical field of frozen soil deformation prediction, and particularly discloses a thermal-mechanical coupling frozen soil deformation rapid prediction method based on a material point method, and the method comprises the steps: building an improved Takashi three-dimensional frost heaving model; thermal-mechanical coupling frozen soil deformation calculation: carrying out initialized background grid boundary division on the predicted frozen soil position; calculating the temperature gradient according to the node temperature, calculating the heat flux density of the material point, and updating the node temperature and the temperature of the material point; judging whether the material point reaches a frost heaving condition or not according to the updated material point temperature, and if the material point reaches the frost heaving condition, performing frost heaving strain calculation; calculating the strain rate and the rotation rate of the substance point, updating the volume of the substance point by using the strain rate of the substance point, and updating the stress of the substance point by using the constitutive relation; calculating node force and updating node momentum, applying displacement boundary conditions again, mapping node acceleration and velocity back to the material point, and updating the velocity and position of the material point; and repeating the calculation of the next time step by using the undeformed grid.
Owner:HARBIN INST OF TECH

A method for generating material point model of soil-rock mixed slope

The present invention discloses a method for generating a material point method model of a soil-rock mixed slope, which is used to simulate the mechanical behavior of a soil-rock mixed slope. The method comprises the following steps: first, randomly dividing the slope area to generate polygonal units that meet the target area and shape distribution; then, based on the shape contours of the polygonal units, generating random block contours through polar coordinate sampling and Fourier series fitting, and controlling the size of the block by adjusting the area ratio; finally, mapping the generated block contours to a material point array, calibrating the material points belonging to the block, and completing the pre-processing of the material point method calculation. The present invention can truly reflect the size, shape, and spatial distribution characteristics of the blocks in the soil-rock mixed slope, effectively improve the efficiency of block placement, avoid overlapping problems, and overcome the defects of the existing technology in the simplification of block shape and insufficient randomness of distribution. At the same time, it is suitable for the numerical simulation of large deformation problems, has high calculation accuracy and broad engineering application prospects.
Owner:SICHUAN UNIV +1

Subsurface erosion simulation numerical method based on semi-implicit two-phase substance point method

The invention discloses a subsurface erosion simulation numerical method based on a semi-implicit two-phase substance point method, and relates to the technical field of geotechnical engineering numerical simulation, and the method comprises the following steps: generalizing unsaturated easily subsurface-eroded accumulated soil into a two-phase multi-component medium based on a mixture theory; establishing a solid-liquid double-phase double-layer grid system; establishing a core control equation of seepage subsurface erosion in the soil body; transferring the material point information of the solid phase and the liquid phase to corresponding background grid nodes in the double-layer grid system; applying a boundary condition on a background grid of the double-layer grid system, and carrying out semi-implicit solution on the core control equation; mapping the obtained node speed to a substance point; judging whether the relative velocity of the solid phase and the liquid phase exceeds a seepage velocity threshold value or not; state variable information carried by the two-phase substance points is updated; correcting permeability and saturation; and judging and calculating whether the specified time is up or whether the soil body reaches the yield limit. The method provided by the invention has important theoretical and engineering practical values for solving the difficulty in simulating the subsurface erosion disaster of the accumulated soil.
Owner:INST OF MOUNTAIN HAZARDS & ENVIRONMENT CHINESE ACADEMY OF SCI

Method for determining differential settlement control indexes of new and old roadbeds of highway reconstruction and extension project based on material point method

The invention discloses a method for determining differential settlement control indexes of new and old roadbeds of a highway reconstruction and extension project based on a material point method, which comprises the following steps of: drilling a pavement structure on a highway site, transporting a sample to a test room for storage, determining mechanical parameters of a pavement structure material under a non-damage condition, establishing a material point model of a corresponding size, and determining the difference settlement control indexes of the new and old roadbeds of the highway reconstruction and extension project. The method comprises the following steps: establishing a material point model, setting a constitutive relationship for the established material point model, applying a displacement load in the perfect material point model according to a roadbed differential settlement action form, calculating material points, performing post-processing by utilizing ParaView software, analyzing the influence of splicing seam expansion on pavement structure cracking, and determining a differential settlement control index of new and old roadbeds. According to the method, the problems of difficulty in sample manufacturing, high time consumption, high cost and the like in an indoor test method are solved, the influence of splicing seam expansion on pavement structure cracking is illustrated, and a new method is provided for determining differential settlement control indexes of new and old roadbeds in highway reconstruction and extension projects.
Owner:SOUTHEAST UNIV

Mixed representation and concurrent solution method for soil-rock mixture

The application discloses a kind of soil and rock mixture mixed representation and concurrent solving method, comprising: after determining the soil and rock block of target soil and rock mixture, soil is modeled with material point method, and the material point corresponding to soil is generated, rock block is modeled with discrete element method, and the discrete unit corresponding to rock block is generated;The interaction between soil and rock block is described with a preset contact model;The virtual radius of each material point is calculated;And determine the material point in contact with discrete unit, marked as virtual particle;The coupling contact force of virtual particle and discrete unit is calculated using discrete element contact model;According to coupling contact force, construct balance equation, and calculate the acceleration on each background grid node in material point method, and the acceleration and angular acceleration on each discrete unit;According to the acceleration on background grid node, the acceleration of discrete unit and the angular acceleration of discrete unit, the real-time speed and displacement of material point and discrete unit are calculated.
Owner:INST OF ROCK & SOIL MECHANICS CHINESE ACAD OF SCI

A simulation method for phase transition of elastic-viscoplastic material based on material point method

The application discloses a simulation method of elastic-viscoplastic material phase transition based on a material point method, which is characterized by the following steps: 1) a unified numerical model for describing the elastic-viscoplastic material and non-Newtonian fluid phenomenon is established for simulating the material in the phase transition process; 2) Allen-Cahn and Cahn-Hilliard phase field equations are discretely modeled and introduced into the material point method; and 3) an elastic-viscoplastic material control strategy driven by phase field evolution is introduced to eliminate the discontinuity in performance caused by the change of physical properties of the mixed contact surface in the process. Compared with the prior art, the application has the advantages that the simulation of the three states of solid, intermediate and liquid of the complex elastic-viscoplastic material is simulated, the details generated by the evolution between phases are simulated, a new flexible phase field evolution based on the material point method and the corresponding material performance can be seamlessly and controllably displayed, and thus a realistic phase transition simulation effect is realized, and the application has a unique advantage in the generation of complex phase transition animation.
Owner:EAST CHINA NORMAL UNIV

Rock damage and failure smooth molecular dynamics analysis method

The application discloses a rock damage and failure smooth molecular dynamics analysis method. The application combines particle failure with rock numerical damage simulation to construct a new rock damage numerical simulation mode. The particle discrete principle of the material point method is used to discretize the calculation material domain. The calculation domain is discretized into particles by using software such as ANSYS. The particles in the calculation domain are endowed with certain material properties. The Mohr-Coulomb criterion commonly used in rock mechanics is used as the failure criterion. When the material reaches the failure condition, the particles are subjected to failure treatment. The failed particles will be permanently failed. The method is simple and easy to implement. The high efficiency and stability of GIMP itself are utilized. The gradual damage and failure process of the rock is simulated by the failure process of the particles. The whole process of the rock damage and failure can be obtained. The research provides a certain reference for the understanding of the smooth particle dynamics method in rock damage numerical simulation.
Owner:HOHAI UNIV +2

Seismic landslide large deformation analysis method considering spatial variability

The invention discloses a seismic landslide large deformation analysis method considering spatial variability, and belongs to the technical field of geotechnical engineering large deformation problem numerical simulation. The method comprises the following steps: firstly, constructing a material point analysis model with spatial variability based on a geometric model of a landslide area and random field statistical characteristics of mechanical parameters of a soil body; secondly, carrying out static analysis on the landslide mass under the action of a self-weight load to obtain a static balance stress field of each material point; and finally, taking the static balance stress field as an initial stress field, carrying out dynamic analysis under the action of self weight and earthquake load to obtain a landslide mass deformation result, and completing earthquake landslide large deformation analysis considering spatial variability. On the basis of a material point method, the spatial variability of soil body parameters is represented based on a random field theory, accurate simulation of the seismic load is realized by combining a two-stage solving strategy, the landslide evolution process of the soil body with the spatial variability under the action of an earthquake is reasonably described, and the seismic load simulation accuracy is improved. And an effective technical support is provided for research on the problem of large deformation of the soil body considering spatial variability.
Owner:DALIAN UNIV OF TECH

Three-dimensional terrain geological modeling method and device based on substance point method simulation

The invention provides a three-dimensional terrain geological modeling method and device based on material point method simulation, and relates to the technical field of geotechnical engineering numerical simulation, and the method comprises the following steps: S1, extracting elevation data of a three-dimensional terrain geological region model; s2, converting the elevation data into three different types of model component data and processing the data; s3, based on the generated model component data, dispersing the model into material points, and generating a material point model; s4, importing the generated material point model into a material point method calculation program to carry out material point method simulation, and obtaining geological large deformation according to the material point method simulation; according to the method, the problem of large deformation simulation modeling caused by complex and diversified terrains and landforms is effectively solved, the method is efficient, stable, simple, convenient and feasible, the modeling efficiency of the substance point method and the quality of the generated substance point model are remarkably improved, and application of substance point method simulation in the field of geotechnical engineering numerical simulation is effectively promoted.
Owner:SHENZHEN UNIV