CN109033537B - Calculation method and system for numerical simulation of rockfill concrete pouring process - Google Patents

Abstract

The embodiment of the invention provides a calculation method and a system for numerical simulation in a rockfill concrete pouring process, wherein the calculation method comprises the following steps: calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the stacking stone initial state according to a finite element/discrete element coupling analysis method FEM/DEM; after the stacking process and the final stacking form of the three-dimensional model of the initial state of the stacking blocks are calculated and analyzed, the pouring process and the final filling state of the self-compacting concrete in the final stacking form of the stacking blocks are calculated and analyzed based on a smooth particle fluid dynamics (SPH) method. The calculation method and the system for numerical simulation of the rockfill concrete pouring process, provided by the embodiment of the invention, can accurately simulate the pouring process of the self-compacting concrete, not only can visually observe the flowing state of the self-compacting concrete in the rockfill pores, but also can know the final compacting state of the rockfill concrete, so that a large amount of labor cost, experimental cost and economic cost are saved, and the problem that the experimental method is difficult to observe on line is avoided.

Description

Calculation method and system for numerical simulation of rockfill concrete pouring process

technical field

The embodiments of the present invention relate to the technical field of rockfill concrete pouring, and more particularly, to a calculation method and system for numerical simulation of the pouring process of rockfill concrete.

Background technique

Mass concrete occupies an important position in modern engineering construction, especially in water conservancy and hydropower engineering construction. In my country, the mass concrete poured in water conservancy and hydropower projects alone is more than 10 million cubic meters every year. In addition, port, airport buildings and heavy machinery foundations also often use mass concrete. Rockfill concrete reduces the amount of cement by using a large amount of boulders (particle size greater than 30cm), thereby effectively reducing the heat of hydration and _CO2 emissions, and has the advantages of small shrinkage of concrete structure, improved crack resistance and shear resistance, fast construction speed, water It has the characteristics of low chemical heat, easy temperature control, high construction quality and low project cost, so it has broad application prospects, and also meets the urgent needs of China to vigorously promote green and low-carbon technologies.

During the construction of rockfill concrete, the accumulation process and final accumulation form of rockfill body have a great influence on the mechanical properties of rockfill concrete after forming. However, due to the high experimental cost and the shape of rockfill body in actual engineering The style is complex, so it is difficult to carry out more accurate experiments to analyze the actual engineering. Therefore, it is an inevitable trend to carry out numerical calculation methods to analyze and calculate the accumulation process of rockfill concrete rockfill. But so far, how to accurately simulate and calculate the pouring construction process of rockfill concrete, there are no results and methods that can be used for reference.

SUMMARY OF THE INVENTION

In view of the problems existing in the prior art, the embodiments of the present invention provide a calculation method and system for numerical simulation of the pouring process of rockfill concrete.

The embodiment of the present invention provides a calculation method for numerical simulation of the pouring process of rockfill concrete, including: calculating and analyzing the stacking process and final stacking shape of the three-dimensional model of the initial state of the rockfill block according to the finite element/discrete element coupling analysis method FEM/DEM; After calculating and analyzing the stacking process and final stacking shape of the 3D model of the initial state of the rockfill, based on the smooth particle hydrodynamic SPH method, the pouring process and final filling of the self-compacting concrete in the final stacking shape of the rockfill are calculated and analyzed. state.

The embodiment of the present invention provides a computing system for numerical simulation of rockfill concrete pouring process, including: a stacking analysis module, used for calculating and analyzing the stacking of the three-dimensional model of the initial state of rockfill blocks according to the finite element/discrete element coupling analysis method FEM/DEM Process and final stacking form; the pouring analysis module is used for calculating and analyzing the stacking process and final stacking form of the 3D model of the initial state of the rockfill block, based on the smooth particle hydrodynamic SPH method, to calculate and analyze the self-compacting concrete in the rockfill. The pouring process and final filling state in the final packed form of the block.

An embodiment of the present invention provides a computing device for numerical simulation of a pouring process of rockfill concrete, including: at least one processor; and at least one memory connected in communication with the processor, wherein: the memory stores data that can be processed by the processor. The program instructions are executed by the processor, and the processor can execute the above calculation method by calling the program instructions.

An embodiment of the present invention provides a non-transitory computer-readable storage medium, where the non-transitory computer-readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the above calculation method.

The calculation method and system for numerical simulation of the pouring process of rockfill concrete provided by the embodiment of the present invention can completely describe the progressive accumulation process of rockfill blocks under the action of stress by setting the finite element and discrete element coupling analysis method for mechanical analysis. The results are more accurate. By setting the SPH method to analyze the pouring process and final filling state of the self-compacting concrete in the final stacking form of the rockfill block, the pouring process of the self-compacting concrete can be accurately simulated, and the self-compacting concrete in the rockfill pores can be observed intuitively. The flow state can also be used to understand the final compaction state of the rockfill concrete. The invention saves a lot of labor cost, experiment cost and economic cost, and avoids the problem that the experimental method is difficult to observe online.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

Fig. 1 is the flow chart of the calculation method embodiment of the numerical simulation of rockfill concrete pouring process of the present invention;

2 is a block diagram of an embodiment of a computing system for numerical simulation of the pouring process of rockfill concrete according to the present invention;

3 is a schematic frame diagram of a computing device for numerical simulation of a pouring process of rockfill concrete in an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

1 is a flowchart of an embodiment of a calculation method for numerical simulation of rockfill concrete pouring process according to the present invention, as shown in FIG. 1 , including: S101 , according to the finite element/discrete element coupling analysis method FEM/DEM, calculate and analyze the initial stage of the rockfill block The stacking process and final stacking form of the state three-dimensional model; S102, after calculating and analyzing the stacking process and final stacking form of the initial state three-dimensional model of the rockfill block, based on the smooth particle hydrodynamics SPH method, calculate and analyze the self-compacting concrete in the stack The pouring process and final filling state in the final stacked form of the stone.

It should be noted that due to the image of the scale effect in the physical model experiment, the physical model experiment at the existing model scale cannot correctly reflect the strength of the real structure, and the prototype physical model experiment is limited by the experimental conditions. By combining the finite element method, which simulates structural stress and deformation, and the discrete element method, which can track the motion of the block, it is called the finite element/discrete element coupled analysis method FEM/DEM, which retains the advantages of each of the finite element and discrete elements. , which can solve the problem of multi-body kinematics and failure mechanics. In the process of calculating the final stacking form of rockfill blocks, there are many rock bodies, complex forces, and rockfill bodies will deform with the change of force. , using the finite element and discrete element coupling analysis method for mechanical analysis, the progressive accumulation process of rockfill blocks under the action of stress can be completely described, and the calculation results are more accurate.

SPH (Smoothed Particle Hydrodynamics) method is the abbreviation of smooth particle hydrodynamics method, which is a meshless method gradually developed in the past 20 years. The basic idea of this method is to describe a continuous fluid (or solid) with an interacting particle group, and each material point carries various physical quantities, including mass, velocity, etc., by solving the dynamic equation of the particle group and tracking each The motion orbit of the particle is obtained, and the mechanical behavior of the whole system is obtained. In the embodiment of the present invention, the SPH method is used to simulate the pouring process of the self-compacting concrete in the rockfill body and calculate the final flow state.

In the calculation method for numerical simulation of the pouring process of rockfill concrete provided by the embodiment of the present invention, by setting the finite element and discrete element coupling analysis method for mechanical analysis, the progressive accumulation process of rockfill blocks under the action of stress can be completely described, and the calculation results are more accurate. to be accurate. By setting the SPH method to analyze the pouring process and final filling state of the self-compacting concrete in the final stacking form of the rockfill block, the pouring process of the self-compacting concrete can be accurately simulated, and the self-compacting concrete in the rockfill pores can be observed intuitively. The flow state can also be used to understand the final compaction state of the rockfill concrete. The invention saves a lot of labor cost, experiment cost and economic cost, and avoids the problem that the experimental method is difficult to observe online.

Based on the above embodiment, the method of calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the initial state of the rockfill block according to the finite element/discrete element coupling analysis method FEM/DEM further includes: establishing a three-dimensional model of the initial state of the rockfill block, The rock pile includes several rock bodies.

Based on the above embodiment, the establishment of a three-dimensional model of the initial state of the rockfill specifically includes: using three-dimensional modeling software such as GID to establish a three-dimensional model of the initial state of the rockfill according to predetermined parameters of the rockfill; The outline of the rock body is 3D scanned to form the input data and input into the 3D modeling software to establish a 3D model of the initial state of the rockfill.

Since the size, type, and quantity of stones required in each project or experiment are different, a three-dimensional model is established based on the actual parameters of the rockfill. size, density, etc.

In the embodiment of the present invention, when collecting the outline of the block stone body, a 3D scanner or a contour measuring instrument may be used for scanning to obtain the shape parameters of the block stone body, which is not specifically limited in the embodiment of the present invention.

This embodiment is helpful for obtaining more accurate and real results when analyzing the stacking process with the finite element/discrete element coupling analysis method in the following.

Based on the above embodiment, the calculation and analysis of the stacking process and final stacking shape of the three-dimensional model of the initial state of the rockfill block, and the calculation and analysis of the final stacking of the self-compacting concrete in the rockfill block based on the smooth particle hydrodynamic SPH method The pouring process and the final filling state in the form further include: establishing a self-compacting concrete model, where the self-compacting concrete model is a Bingham rheological model.

Specifically, the self-compacting concrete model is:

Among them, τ ₀ is the yield strength, μ _p is the plastic viscosity, τ is the shear stress; γ is the shear strain rate.

It should be noted that the Bingham model: a mechanical model that reflects the viscous, elastic, plastic rheological characteristics of rock and soil and its process by connecting the buffer and the slider in parallel, and then connecting them in series with the spring.

Based on the above embodiment, the calculation and analysis of the pouring process and the final filling state of the self-compacting concrete in the final stacking form of the rockfill block based on the smooth particle hydrodynamic SPH method specifically include: based on the SPH method, iterating over time step by step Update the density, position and velocity of the fluid particles in the self-compacting concrete model; based on the density, position and velocity of the fluid particles, analyze the pouring process and final filling state of the self-compacting concrete in the final stacking form of the rockfill block .

The required functions and equations of the present embodiment are further described below, and the discrete form of SPH in the embodiment of the present invention is:

where: N is the total number of adjacent particles in the support domain; x _j is the position of particle _j ; m _j and ρ _j are the mass and density of particle j, respectively; The distance is related to the smooth length h.

The kernel function selected in this embodiment is:

Among them, d is the spatial dimension; h is the smooth length.

where C is a normalization constant.

The state equation selected in this embodiment is:

ρ₀是粒子的初始密度；γ为一恒定系数；C为人为音速，出于数值计算稳定性和时间步长考虑，通常取一个比真实音速小得多的值，一般取流场最大流速值的10倍，即

H为自由液面高度。Among them, B is used as the initial pressure to limit the maximum change of density, and the present invention takes

ρ ₀ is the initial density of the particle; γ is a constant coefficient; C is the artificial speed of sound. For the stability of numerical calculation and the time step, a value much smaller than the true speed of sound is usually taken, and the maximum flow velocity value of the flow field is generally taken. 10 times the

H is the free surface height.

The displacement relation of particles is:

Among them, r is the position vector of the particle point, and u is the velocity vector of the particle.

The boundary processing method in the embodiment of the present invention is as follows: the solid wall particles participate in the calculation of the control equation, but their positions are fixed, and the displacement is set to 0 in the present invention. The Lennard-Jones repulsive force method can generally be used for the interaction between boundary particles and fluid particles, that is, it is assumed that when the fluid particles are close enough to the solid wall, in order to prevent the internal fluid particles from flying through the solid wall boundary and causing the calculation to collapse, the boundary particles will The approaching fluid particles exert a central repulsive force, and the magnitude of the repulsive force is determined by the mutual distance, projection speed, height position, etc. The free surface adopts the algorithm proposed by Koshizuka et al. to realize the Dirichlet condition, and the particle pressure at the interface is assigned as 0 or a certain external pressure value.

Based on the above embodiment, the iteratively updating the density, position and velocity of the fluid particles in the self-compacting concrete model by time step, specifically includes: calculating the density change of the fluid particles through a continuity equation, time by step. , capture the free surface particles and perform density correction of the free surface particles to obtain the density field at each moment in the self-compacting concrete model; each time step, update the trajectory of each fluid particle motion through the fluid particle displacement equation, and obtain any The position of the fluid particle at each moment; for each time step, the pressure of any fluid particle is determined through the equation of state, the acceleration generated by the external force is calculated based on the pressure of each fluid particle, and the self-compacting concrete is calculated through the momentum equation based on the acceleration. The velocity field at each moment in the model.

It should be noted that the particle search adopts the tree search method or the associated linked list search technology.

The calculation method for the numerical simulation of the pouring process of rockfill concrete provided by the embodiment of the present invention can accurately calculate the pouring of rockfill concrete by iteratively updating the density, position and velocity of the fluid particles in the self-compacting concrete model by setting time steps. process.

Based on the above embodiment, calculating and analyzing the stacking process and final stacking shape of the three-dimensional model of the initial state of rockfill blocks according to the finite element/discrete element coupling analysis method FEM/DEM specifically includes: obtaining the stack according to the finite element analysis method FEM The mechanical behavior of the continuum of each rock mass in the three-dimensional model of the initial state of the rock block; the discontinuous medium mechanical behavior between the rock bodies in the three-dimensional model of the initial state of the rockfill block is obtained according to the discrete element analysis method DEM; The continuum mechanical behavior and discontinuous medium mechanical behavior are substituted into the dynamic balance equation of the three-dimensional model of the initial state of the rockfill block, and the accumulation process and final accumulation form are obtained.

It should be noted that Finite Element Analysis (FEA, Finite Element Analysis) uses mathematical approximation to simulate the real physical system (geometry and load conditions). Using simple but interacting elements, a finite number of unknowns can be used to approximate a real system with infinite unknowns. It regards the solution domain as consisting of many small interconnected sub-domains called finite elements, assumes a suitable approximate solution for each element, and then derives the total satisfying conditions for solving this domain, so as to obtain the solution of the problem.

Continuum mechanics is a branch of physics that deals with the macroscopic properties of so-called "continuum", including solids and fluids. For example, conservation of mass, theorems of momentum and angular momentum, conservation of energy, etc. In continuum mechanics, the space occupied by real fluids or solids can be approximately regarded as being filled with "particles" continuously without voids (that is, molecular groups that are sufficiently large on the microscopic scale and sufficiently small on the macroscopic scale). The macroscopic physical quantities (such as mass, velocity, pressure, temperature, etc.) of a particle satisfy all physical laws that should be followed, such as the law of conservation of mass, Newton's law of motion, law of conservation of energy, laws of thermodynamics, and transport properties such as diffusion, viscosity, and heat conduction . This assumption ignores the specific microstructure of matter (the study of the microstructure of solids belongs to the category of condensed matter physics), and uses a set of partial differential equations to express macroscopic physical quantities (such as mass, degrees, pressure, etc.).

Discrete element analysis is a numerical simulation method specially used to solve the problem of discontinuous medium. This method regards the rockfill block as consisting of discrete blocks and joint surfaces between the blocks, allowing the blocks to translate, rotate and deform, while the joint surfaces can be compressed, separated or slipped. Therefore, the rockfill is regarded as a discontinuous discrete medium. There can be large displacement, rotation and sliding and even block separation inside, so that the nonlinear large deformation characteristics in rockfill blocks can be simulated more realistically.

The general solution process of the discrete element method is: discretize the solution space into a discrete element array, and connect two adjacent elements with reasonable connecting elements according to the actual problem; the relative displacement between elements is the basic variable, which is determined by the force and relative displacement. The normal and tangential forces between the two elements can be obtained; the forces between the element and other elements in all directions and the external forces caused by other physical fields acting on the element can be obtained. According to Newton's second law of motion The acceleration of the element can be obtained; it is time-integrated to obtain the velocity and displacement of the element. Thereby, physical quantities such as velocity, acceleration, angular velocity, linear displacement and rotation angle of all units at any time can be obtained.

On the basis of the above embodiment, this embodiment further illustrates the specific process of obtaining the mechanical behavior of the continuum of each rock mass in the three-dimensional model of the initial state of the rockfill block according to the finite element analysis method FEM.

Specifically, the mechanical behavior of the continuum includes: the internal force vector caused by the deformation of the nodes of the grid element, the external force vector of the nodes of the grid element, and the mass matrix.

Correspondingly, obtaining the continuum mechanical behavior of each rock body in the three-dimensional model according to the finite element analysis method is specifically:

The three-dimensional model of the initial state of the rockfill block is meshed to obtain a finite element model composed of mesh elements.

The internal force vector is obtained from the mesh element volume, the canonical function, and the Cauchy stress tensor.

The mass matrix is obtained from the undeformed volume of the mesh element, the density corresponding to the undeformed volume of the mesh element, and the canonical function.

The external force vector is obtained according to the physical force, the surface force and the surface area of the unit of the rock body.

Further, the internal force vector is calculated as follows:

where V is the unit volume, N is the standard shape function, and T is the Cauchy stress tensor.

The nodal external force vector is calculated as follows:

Among them, b is the physical force, t is the surface force, and S is the unit surface area.

The mass matrix is calculated as:

Among them, V ₀ is the volume of the unit when it is not deformed, and ρ ₀ represents the density corresponding to V ₀ .

On the basis of the above embodiment, this embodiment further illustrates the specific process of obtaining the mechanical behavior of discontinuous medium between the rock bodies in the three-dimensional model of the initial state of the rockfill block according to the discrete element analysis method DEM.

Specifically, the mechanical behavior of the discontinuous medium includes: the contact force between the boulders.

Correspondingly, the mechanical behavior of the discontinuous medium between the blocks in the three-dimensional model obtained according to the discrete element analysis method is specifically:

Through the non-binary tree search contact algorithm (the contact judgment method adopts the non-binary tree search contact algorithm proposed by Munjiza and Andrews, that is, the efficient NBS algorithm, this algorithm occupies a small memory, and can achieve fast inter-unit for the case of similar block unit sizes. Contact search) to obtain contact and target bodies in the 3D model.

Obtain the contact body and the target body in the 3D model through the non-binary tree search contact algorithm;

获得接触体和目标体之间的法向接触力；其中，β_c和β_t分别表示接触体和目标体，m和n分别表示用于离散接触体和目标体的有限单元数目，

表示接触势，S表示相互嵌入部分的边界，n表示该边界的外法线方向矢量。According to the formula:

Obtain the normal contact force between the contact and target; where β _c and β _t denote the contact and target, respectively, m and n denote the number of finite elements used to discretize the contact and target, respectively,

represents the contact potential, S represents the boundary of the mutually embedded part, and n represents the outer normal direction vector of the boundary.

获得接触体和目标体之间的切向接触力；其中k_t为切向刚度，η_t为切向粘性阻尼系数，d_t和v_t分别表示切向相对位移和相对速度。According to the formula:

The tangential contact force between the contact body and the target body is obtained; where k _t is the tangential stiffness, η _t is the tangential viscous damping coefficient, and d _t and v _t represent the tangential relative displacement and relative velocity, respectively.

则根据库伦摩擦定律，重新根据公式

计算所述切向接触力。If judged

Then according to Coulomb's friction law, according to the formula again

Calculate the tangential contact force.

The contact force is taken as the vector sum of the normal contact force and the tangential contact force.

On the basis of the above embodiment, the finite element discrete form of the dynamic balance equation of the three-dimensional model of the initial state of the rockfill block is:

x=X+u;

和

分别表示有限元节点的加速度和速度，X为有限元节点的初始位置向量，u为有限元节点的位移向量。Among them, M and C represent the mass matrix and damping matrix, respectively, f ^int represents the internal force vector caused by deformation, f ^c represents the contact force, f ^ext represents all the external force vectors except the contact force,

and

respectively represent the acceleration and velocity of the finite element node, X is the initial position vector of the finite element node, and u is the displacement vector of the finite element node.

As a preferred embodiment, the calculation method for the numerical simulation of the pouring process of rockfill concrete in the embodiment of the present invention specifically includes:

A three-dimensional model of the initial state of the rockfill block is established, and the rockfill block includes several rock bodies.

According to the finite element/discrete element coupling analysis method FEM/DEM, the accumulation process and final accumulation form of the 3D model of the initial state of rockfill blocks are calculated and analyzed.

The final stacking form of the three-dimensional model of the initial state of the rockfill block is input in the form of a boundary, and a self-compacting concrete model is established, and the self-compacting concrete model is the Bingham rheological model.

Based on the smooth particle hydrodynamic SPH method, the pouring process and final filling state of self-compacting concrete in the final stacking form of rockfill blocks are calculated and analyzed.

In the embodiment of the present invention, Paraview software is used as the post-processing software to process the calculation result. It should be noted that Paraview software itself is a mature software for processing numerical calculation results. It mainly analyzes the visual processing of the pouring process of rockfill concrete, as well as the analysis of the velocity field, the stress field and the display of the memory compactness of the final pouring state.

Establishing a three-dimensional model of the initial state of the rockfill block, where the rockfill block includes several rock bodies, specifically including: using a three-dimensional modeling software to establish a three-dimensional model of the initial state of the rockfill block according to predetermined parameters of the rockfill block; or, 3D scanning is performed on the outline of the rock body to form input data and input into the three-dimensional modeling software to establish a three-dimensional model of the initial state of the rockfill block.

According to the finite element/discrete element coupling analysis method FEM/DEM, calculate and analyze the accumulation process and final accumulation form of the three-dimensional model of the initial state of the rockfill block, which specifically includes: obtaining the three-dimensional model of the initial state of the rockfill block according to the finite element analysis method FEM. The continuum mechanical behavior of each rock mass; the discontinuous media mechanical behavior between the rock bodies in the three-dimensional model of the initial state of the rockfill block is obtained according to the discrete element analysis method DEM; the continuum mechanical behavior and non-continuous media mechanical behavior of all rock bodies are The mechanical behavior of the continuum is substituted into the dynamic equilibrium equation of the three-dimensional model of the initial state of the rockfill block to obtain the stacking process and final stacking form.

Based on the SPH method of smooth particle hydrodynamics, calculate and analyze the pouring process and final filling state of self-compacting concrete in the final stacking form of rockfill blocks, including: based on the SPH method, iteratively update the self-compacting concrete model by time step. The density, position and velocity of the fluid particles in the rockfill; based on the density, position and velocity of the fluid particles, the pouring process and final filling state of the self-compacting concrete in the final stacking form of the rockfill block are analyzed.

Based on the above embodiment, FIG. 2 is a block diagram of an embodiment of a computing system for numerical simulation of the pouring process of rockfill concrete according to the present invention, as shown in FIG. FEM/DEM, calculates and analyzes the stacking process and final stacking shape of the 3D model of the initial state of the rockfill block; the pouring analysis module 202 is used to calculate and analyze the stacking process and final stacking shape of the 3D model of the initial state of the rockfill block, based on The smooth particle hydrodynamic SPH method is used to calculate and analyze the pouring process and final filling state of self-compacting concrete in the final stacking form of rockfill.

The short message distribution system of the embodiment of the present invention can be used to implement the technical solution of the calculation method embodiment of the numerical simulation of the pouring process of rockfill concrete shown in FIG.

Based on the above embodiment, FIG. 3 is a schematic frame diagram of a computing device for numerical simulation of the pouring process of rockfill concrete in an embodiment of the present invention. Referring to FIG. 3 , an embodiment of the present invention provides a computing device for numerical simulation of a pouring process of rockfill concrete, including: a processor 310 , a communications interface 320 , a memory 330 and a bus 340 , wherein , the processor 310 , the communication interface 320 , and the memory 330 communicate with each other through the bus 340 . The processor 310 can call the logic instructions in the memory 330 to execute the following methods, including: calculating and analyzing the stacking process and final stacking shape of the three-dimensional model of the initial state of the rockfill block according to the finite element/discrete element coupling analysis method FEM/DEM; After calculating and analyzing the stacking process and final stacking shape of the 3D model of the initial state of the rockfill block, based on the smooth particle hydrodynamic SPH method, the pouring process and final filling state of the self-compacting concrete in the final stacking shape of the rockfill block were calculated and analyzed. .

An embodiment of the present invention discloses a computer program product, where the computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program includes program instructions, and when the program instructions are executed by a computer, The computer can execute the calculation methods provided by the above method embodiments, for example, including: according to the finite element/discrete element coupling analysis method FEM/DEM, calculating and analyzing the stacking process and final stacking shape of the three-dimensional model of the initial state of the rockfill; After the stacking process and final stacking form of the three-dimensional model of the initial state of the rockfill block, based on the smooth particle hydrodynamic SPH method, the pouring process and final filling state of the self-compacting concrete in the final stacking state of the rockfill block are calculated and analyzed.

Based on the foregoing embodiments, embodiments of the present invention provide a non-transitory computer-readable storage medium, where the non-transitory computer-readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the methods described in the foregoing method embodiments. The provided calculation methods include, for example: calculating and analyzing the stacking process and final stacking shape of the three-dimensional model of the initial state of the rockfill block according to the finite element/discrete element coupling analysis method FEM/DEM; calculating and analyzing the three-dimensional model of the initial state of the rockfill block. After the accumulation process and final accumulation form of rockfill blocks, the pouring process and final filling state of self-compacting concrete in the final accumulation form of rockfill blocks were calculated and analyzed based on the smooth particle hydrodynamic SPH method.

Those of ordinary skill in the art can understand that the implementation of the above device embodiments or method embodiments is merely illustrative, wherein the processor and the memory may be physically separated components or may not be physically separated, that is, they may be located in One place, or it can be distributed over multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution in this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

From the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and certainly can also be implemented by hardware. Based on this understanding, the above-mentioned technical solutions can be embodied in the form of software products in essence or the parts that make contributions to the prior art, and the computer software products can be stored in computer-readable storage media, such as U disk, mobile hard disk , ROM/RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods described in various embodiments or parts of embodiments.

The calculation method and system for numerical simulation of the pouring process of rockfill concrete provided by the embodiment of the present invention can completely describe the progressive accumulation process of rockfill blocks under the action of stress by setting the finite element and discrete element coupling analysis method for mechanical analysis. The results are more accurate. By setting the SPH method to analyze the pouring process and final filling state of the self-compacting concrete in the final stacking form of the rockfill block, the pouring process of the self-compacting concrete can be accurately simulated, and the self-compacting concrete in the rockfill pores can be observed intuitively. The flow state can also be used to understand the final compaction state of the rockfill concrete. The invention saves a lot of labor cost, experiment cost and economic cost, and avoids the problem that the experimental method is difficult to observe online. By setting iteratively updating the density, position and velocity of fluid particles in the self-compacting concrete model by time step, the pouring process of rockfill concrete can be accurately calculated.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be The technical solutions described in the foregoing embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (7)

1. A calculation method for numerical simulation in a rockfill concrete pouring process is characterized by comprising the following steps:

calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the stacking stone initial state according to a finite element/discrete element coupling analysis method FEM/DEM;

after the stacking process and the final stacking form of the three-dimensional model of the initial state of the stacking blocks are calculated and analyzed, the pouring process and the final filling state of the self-compacting concrete in the final stacking form of the stacking blocks are calculated and analyzed based on a smooth particle fluid dynamics (SPH) method;

iteratively updating the density, the position and the speed of fluid particles in the self-compacting concrete model one by one according to a time step based on an SPH (shortest path H) method;

analyzing the pouring process and the final filling state of the self-compacting concrete in the final stacking form of the stacking blocks based on the density, the position and the speed of the fluid particles;

wherein, the iteratively updating the density, the position and the speed of the fluid particles in the self-compacting concrete model one by one time step specifically comprises:

calculating the density change of the fluid particles one by one according to a continuity equation, capturing free surface particles and correcting the density of the free surface particles to obtain a density field of the self-compacting concrete model at each moment;

updating the motion track of each fluid particle through a fluid particle displacement equation one by one time step to obtain the position of any fluid particle at each moment;

determining the pressure of any fluid particle through a state equation one by one according to the time step, calculating the acceleration generated by the external force based on the pressure of each fluid particle, and calculating the velocity field of each moment in the self-compacting concrete model through a momentum equation based on the acceleration;

the method for calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the stacking stone initial state according to the finite element/discrete element coupling analysis method FEM/DEM specifically comprises the following steps:

obtaining the continuous medium mechanical behavior of each rock block in the three-dimensional model of the stacking initial state of the rock blocks according to a finite element analysis (FEM);

obtaining the mechanical behavior of a non-continuous medium among the rock masses in the three-dimensional model of the initial state of the rock pile according to a discrete element analysis (DEM);

substituting the continuous medium mechanical behaviors and the non-continuous medium mechanical behaviors of all the rock masses into a dynamic balance equation of the three-dimensional model of the initial state of the rock mass pile to obtain the stacking process and the final stacking form;

the continuous medium mechanical behavior comprises: an internal force vector caused by node deformation of the grid unit, an external force vector of the node of the grid unit and a mass matrix;

the method for obtaining the continuous medium mechanical behavior of each block stone body in the three-dimensional model according to the finite element analysis method specifically comprises the following steps:

carrying out mesh division on the three-dimensional model of the rock-fill block in the initial state to obtain a finite element model consisting of mesh units;

obtaining the internal force vector according to the grid unit volume, the standard type function and the Cauchy stress tensor;

obtaining the quality matrix according to the volume of the grid unit when the grid unit is not deformed, the density corresponding to the volume of the grid unit when the grid unit is not deformed and the standard function;

obtaining the external force vector according to the physical strength, the surface force and the unit surface area of the stone body;

the mechanical behavior of the non-continuous medium comprises: contact force between the stone bodies;

the method for obtaining the mechanical behavior of the non-continuous medium between the rock masses in the three-dimensional model according to the discrete element analysis method specifically comprises the following steps:

obtaining a contact body and a target body in the three-dimensional model through a non-binary tree search contact algorithm;

and taking the vector sum of the normal contact force and the tangential contact force as the contact force.

2. The method according to claim 1, wherein the step of computationally analyzing the stacking process and the final stacking shape of the three-dimensional model of the stacking blocks in the initial state according to the finite element/discrete element coupling analysis method FEM/DEM further comprises:

and establishing a three-dimensional model of the initial state of the rock stacking block, wherein the rock stacking block comprises a plurality of block stone bodies.

3. The method of claim 1, wherein the step of computationally analyzing the stacking process and the final stacking state of the three-dimensional model of the initial state of the stacking blocks, and the step of computationally analyzing the pouring process and the final filling state of the self-compacting concrete in the final stacking state of the stacking blocks based on the Smooth Particle Hydrodynamics (SPH) method further comprises:

and establishing a self-compacting concrete model, wherein the self-compacting concrete model is a Bingham rheological model.

4. The calculation method according to claim 2, wherein the establishing of the three-dimensional model of the stacking block initial state specifically comprises:

establishing a three-dimensional model of the rock stacking block in an initial state by using three-dimensional modeling software according to predetermined parameters of the rock stacking block; or,

and 3D scanning the outline of the rock mass body to form input data, inputting the input data into three-dimensional modeling software, and establishing a three-dimensional model of the rock mass in the initial state.

5. A computing system for numerical simulation of a rockfill concrete placement process, comprising:

the stacking analysis module is used for calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the stacking stone initial state according to a finite element/discrete element coupling analysis method FEM/DEM;

the pouring analysis module is used for calculating and analyzing the pouring process and the final filling state of the self-compacting concrete in the final stacking form of the stacking blocks based on a smooth particle fluid dynamics (SPH) method after calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the initial state of the stacking blocks;

iteratively updating the density, the position and the speed of fluid particles in the self-compacting concrete model one by one according to a time step based on an SPH (shortest path H) method;

analyzing the pouring process and the final filling state of the self-compacting concrete in the final stacking form of the stacking blocks based on the density, the position and the speed of the fluid particles;

wherein, the iteratively updating the density, the position and the speed of the fluid particles in the self-compacting concrete model one by one time step specifically comprises:

calculating the density change of the fluid particles one by one according to a continuity equation, capturing free surface particles and correcting the density of the free surface particles to obtain a density field of the self-compacting concrete model at each moment;

updating the motion track of each fluid particle through a fluid particle displacement equation one by one time step to obtain the position of any fluid particle at each moment;

determining the pressure of any fluid particle through a state equation one by one according to the time step, calculating the acceleration generated by the external force based on the pressure of each fluid particle, and calculating the velocity field of each moment in the self-compacting concrete model through a momentum equation based on the acceleration;

the method for calculating and analyzing the stacking process and the final stacking form of the three-dimensional model of the stacking stone initial state according to the finite element/discrete element coupling analysis method FEM/DEM specifically comprises the following steps:

obtaining the continuous medium mechanical behavior of each rock block in the three-dimensional model of the stacking initial state of the rock blocks according to a finite element analysis (FEM);

obtaining the mechanical behavior of a non-continuous medium among the rock masses in the three-dimensional model of the initial state of the rock pile according to a discrete element analysis (DEM);

substituting the continuous medium mechanical behaviors and the non-continuous medium mechanical behaviors of all the rock masses into a dynamic balance equation of the three-dimensional model of the initial state of the rock mass pile to obtain the stacking process and the final stacking form;

the continuous medium mechanical behavior comprises: an internal force vector caused by node deformation of the grid unit, an external force vector of the node of the grid unit and a mass matrix;

the method for obtaining the continuous medium mechanical behavior of each block stone body in the three-dimensional model according to the finite element analysis method specifically comprises the following steps:

carrying out mesh division on the three-dimensional model of the rock-fill block in the initial state to obtain a finite element model consisting of mesh units;

obtaining the internal force vector according to the grid unit volume, the standard type function and the Cauchy stress tensor;

obtaining the quality matrix according to the volume of the grid unit when the grid unit is not deformed, the density corresponding to the volume of the grid unit when the grid unit is not deformed and the standard function;

obtaining the external force vector according to the physical strength, the surface force and the unit surface area of the stone body;

the mechanical behavior of the non-continuous medium comprises: contact force between the stone bodies;

the method for obtaining the mechanical behavior of the non-continuous medium between the rock masses in the three-dimensional model according to the discrete element analysis method specifically comprises the following steps:

obtaining a contact body and a target body in the three-dimensional model through a non-binary tree search contact algorithm;

and taking the vector sum of the normal contact force and the tangential contact force as the contact force.

6. A computing device for numerical simulation of a rockfill concrete placement process, comprising:

at least one processor; and

at least one memory communicatively coupled to the processor, wherein:

the memory stores program instructions executable by the processor, the processor being capable of performing the computing method of any of claims 1 to 4 when invoked by the program instructions.

7. A non-transitory computer-readable storage medium storing computer instructions for causing a computer to perform the computing method of any one of claims 1 to 4.

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