CN-122021221-A - High-intensity earthquake region side slope catastrophe chain evolution simulation method

CN122021221ACN 122021221 ACN122021221 ACN 122021221ACN-122021221-A

Abstract

The invention relates to the technical field of geotechnical engineering, in particular to a high-intensity earthquake region slope catastrophe chain evolution simulation method, which comprises the steps of constructing a model to generate particles and dividing grids to obtain an initial discrete model; dynamically reordering GPU data according to particle space positions, optimizing a video memory access layout, executing adjacent search and stress calculation in parallel based on the layout, selecting a constitutive path according to a mechanical state, identifying a slip plane through state, mapping earthquake motion to boundary particles, applying a dynamic boundary, updating boundary stress attributes, solving a momentum equation, updating the particle state, and circularly optimizing the layout according to frequency. According to the invention, through GPU parallel optimization and improved boundary processing, efficient and accurate simulation of the whole process from elastic deformation to large deformation instability of the side slope under seismic loading is realized.

Inventors

ZHOU XINGBO
ZHANG KAI
ZHOU MINGJUN
LIU YONG
Yang Ziru
ZHENG HAOLEI
CHEN WENLONG
CHENG JIALIN
ZHANG YUN

Assignees

水电水利规划设计总院

Dates

Publication Date: 20260512
Application Date: 20260325

Claims (10)

1. The method for simulating the disaster chain evolution of the side slope in the high-intensity earthquake region is characterized by comprising the following steps of: Step S1, constructing a rock-soil slope geometric model, generating SPH particles in a calculation domain, dividing the particles into internal real particles and virtual particle boundary layers, and constructing a linked list search structure by using a background grid to obtain an initial discrete model; Step S2, dynamically reordering the particle data in the GPU memory according to the space positions of particles in the initial discrete model, so that the particle data adjacent to the physical space continuously obtain the data layout with optimized video memory access on the memory address; Step S3, performing adjacent particle search and stress calculation based on the data layout, and selecting a corresponding constitutive calculation path for parallel processing according to the current mechanical response state of the particles in the calculation process to obtain the stress state of the particles; s4, identifying a slip plane and a through state of the slip plane according to the stress state of the particles, mapping seismic data to boundary particles, applying dynamic boundary conditions, and updating stress properties of the boundary particles according to the through state of the slip plane to obtain a model state containing seismic dynamic response; and S5, based on the model state, solving a momentum equation in parallel through the GPU to update the speed and the position of the particles, and performing step S2 according to a preset frequency jump to perform data layout optimization, otherwise, performing step S3 to step S5 in a circulating way until the preset simulation time is reached.
2. The method for simulating the catastrophe chain evolution of the side slope in the earthquake region with high intensity according to claim 1, wherein the process of the step S2 comprises the following steps: Calculating the background grid number of the particle according to the space coordinate of the current moment; According to a preset reordering period, using the background grid number as a sequencing key, and performing replacement operation on a data array storing particle positions and attributes in a GPU global memory by using a parallel base sequencing algorithm; and adjusting the replaced data storage addresses into a space layout which is continuously arranged according to the background grid numbers, so that the particle data in the same grid and the adjacent grids are continuously stored on the video memory addresses to obtain the data layout.
3. The simulation method for the catastrophic chain evolution of the side slope of the high-intensity earthquake region according to claim 2, wherein the reordering period is dynamically adjusted according to the expansion speed or the slip plane through state of the side slope plastic region, the reordering frequency is increased in the rapid expansion stage of the plastic region, and the reordering frequency is reduced in the small deformation stage of the side slope.
4. The method for simulating the catastrophe chain evolution of the side slope of the high-intensity earthquake region according to claim 3, wherein the process of the step S3 comprises the following steps: the heuristic stress state of each particle is calculated in parallel in the GPU thread bundle, and the distance between the current stress state and the yield surface is calculated according to the yield function; generating a state mask vector according to the distance, wherein the state mask vector is a continuous numerical vector or a discrete identification vector based on the distance; Constructing a stress update equation comprising an elastic prediction term and a plastic correction term, and introducing the state mask vector into the stress update equation as a weighting factor through arithmetic operation; And (3) performing unified vector operation on all particles in the calculation domain, and mapping the heuristic stress of the plastic state particles back to the yield surface to obtain an updated particle stress state.
5. The method for simulating the catastrophic chain evolution of a slope in a high intensity seismic area according to claim 4, wherein the process of calculating the heuristic stress state of each particle in parallel in the GPU thread bundle and calculating the distance of the current stress state relative to the yield surface according to the yield function comprises the following steps: Based on the relative speeds of the particles and the adjacent particles, using a kernel function to approximate the velocity gradient tensor of the particles; according to the velocity gradient tensor, combining a preset elastic constitutive matrix and a current time step, updating to obtain a heuristic stress tensor assuming that the particles only elastically deform; calculating a first stress invariant and a second bias stress invariant of the heuristic stress tensor; determining the radius of a yield surface under the current hydrostatic pressure according to the first stress invariant and the rock-soil body shear strength parameter; and calculating the difference between the square root of the second bias stress invariant and the radius of the yielding surface, and taking the difference as the distance between the current stress state and the yielding surface.
6. The method for simulating the catastrophe chain evolution of a side slope in a high intensity earthquake region according to claim 5, wherein the process of identifying the slip plane and the penetration state thereof according to the particle stress state comprises the following steps: Extracting equivalent plastic strain or accumulated plastic shear strain of each particle according to the stress state of the particle; screening particles with equivalent plastic strain or accumulated plastic shear strain larger than a preset threshold value as potential slip band particles, and judging whether a continuous band-shaped region penetrating through the surface and the bottom of the side slope exists or not by using a communication region analysis algorithm; if so, the slip plane penetration is determined, and the continuous band-shaped region is marked as a penetration slip plane.
7. The method for simulating the catastrophic chain evolution of a side slope in a high intensity seismic area according to claim 6, wherein the mapping of seismic data to boundary particles and the application of dynamic boundary conditions comprises: acquiring earthquake motion acceleration time course data and converting the earthquake motion acceleration time course data into a speed time course or a stress time course; Generating boundary solid particles at the bottom of a calculation domain, and giving the boundary solid particles with the velocity time interval as a boundary wall velocity; The contact stress at the boundary is calculated by the velocity gradient and the seismic forces are transferred to the upper rock-soil mass in the form of stress waves.
8. The method for simulating the catastrophic chain evolution of a side slope in a high intensity seismic area according to claim 7, wherein the applying power boundary condition further comprises: A slipping boundary mode or a non-slipping boundary mode is selected according to the boundary position, wherein, Adopting a non-slip mode for the simulated horizontal plane boundary, calculating the speed of boundary particles according to the difference value between the speed of a boundary wall and the speed of adjacent rock-soil mass particles, and limiting tangential movement; And adopting a sliding mode for simulating the boundary of the vertical plane, allowing boundary particles to move along with the rock-soil body in the vertical direction, and only applying reverse speed constraint in the horizontal direction, wherein the stress of the boundary particles is calculated in a projection mode according to the main stress direction.
9. The simulation method for the disaster chain evolution of the side slope of the high-intensity earthquake region according to claim 8, wherein the process of updating the stress attribute of the boundary particles according to the through state of the slip plane comprises the following steps: when the slip plane is penetrated and large deformation occurs, setting the residual rock-soil body particles below the penetrated slip plane as dynamic virtual boundary particles; constructing dual stress attributes for the dynamic virtual boundary particles; and updating the stress field of the boundary particles according to the dual stress attribute to obtain the model state.
10. The method for simulating the catastrophic chain evolution of a side slope in a high intensity seismic area according to claim 9, wherein the process of constructing dual stress properties for the dynamic virtual boundary particles comprises: when the sliding surface is interacted with the upper landslide body, virtual particle stress calculated by an interpolation method is adopted to simulate contact separation and friction energy consumption of the sliding surface; The physical particle stress is adopted when the physical particle stress interacts with the rock mass particles at the lower part, so that the material property of the rock mass body is maintained.

Description

High-intensity earthquake region side slope catastrophe chain evolution simulation method Technical Field The invention relates to the technical field of geotechnical engineering, in particular to a high-intensity earthquake region slope catastrophe chain evolution simulation method. Background Dynamic response analysis of a rock-soil slope under the action of earthquake load is core content for evaluating engineering earthquake-resistant safety. At present, numerical simulation for the whole earthquake loading process of a rock-soil side slope mainly depends on a grid type method and a discrete element method. The Finite Element Method (FEM) is used as a mature numerical analysis tool, and can accurately simulate the propagation and attenuation of seismic waves, but when the slope sliding, instability and large deformation damage stage is processed, calculation is usually terminated due to grid distortion or distortion, and the whole process from elastic deformation to instability damage is difficult to realize. Although the Discrete Element Method (DEM) can naturally simulate the rupture and large displacement movement of a rock-soil body without grid constraint, the discrete contact-based algorithm logic causes huge calculation amount, and has a high-frequency filtering effect when simulating the propagation of earthquake fluctuation, so that the high-efficiency calculation requirement of the long-time earthquake power time course analysis of a large-scale engineering site is difficult to meet. The smooth particle fluid dynamics method (SPH) is used as a gridless particle method, has the free interface tracking capability of the Lagrange method and the constitutive simulation capability of continuous medium mechanics, and provides a new way for solving the problems. However, the conventional SPH-based slope seismic analysis method still has the technical bottlenecks that firstly, in terms of calculation efficiency, when a GPU (graphic processing unit) performs parallel calculation, the storage sequence of particle data is often based on an initial ID (identification) instead of a physical space position, so that display memory access is discontinuous when threads access neighbor particle data, the exertion of the high bandwidth advantage of the GPU is severely restricted, and the calculation efficiency of a large-scale particle system is limited, and secondly, in terms of boundary processing, the conventional method is generally difficult to dynamically adapt to the boundary evolution process after the instability of a slope, particularly, after a sliding surface is penetrated, the dual roles of a lower rock body serving as a 'residual rock body' and a 'new boundary' cannot be effectively distinguished, so that stress transfer is distorted at a contact interface of a sliding body and a bedrock, and the accuracy of dynamic response calculation in a large deformation stage is influenced. Therefore, a calculation method capable of achieving accurate simulation of the whole process of the seismic loading of the rock-soil slope by combining high calculation efficiency and dynamic boundary adaptability is needed. Disclosure of Invention Therefore, the invention provides a simulation method for the catastrophe chain evolution of a side slope in a high-intensity earthquake region, which is used for solving the problems in the prior art. In order to achieve the above purpose, the invention provides a method for simulating the disaster chain evolution of a slope in a high-intensity earthquake region, which comprises the following steps: Step S1, constructing a rock-soil slope geometric model, generating SPH particles in a calculation domain, dividing the particles into internal real particles and virtual particle boundary layers, and constructing a linked list search structure by using a background grid to obtain an initial discrete model; Step S2, dynamically reordering the particle data in the GPU memory according to the space positions of particles in the initial discrete model, so that the particle data adjacent to the physical space continuously obtain the data layout with optimized video memory access on the memory address; Step S3, performing adjacent particle search and stress calculation based on the data layout, and selecting a corresponding constitutive calculation path for parallel processing according to the current mechanical response state of the particles in the calculation process to obtain the stress state of the particles; s4, identifying a slip plane and a through state of the slip plane according to the stress state of the particles, mapping seismic data to boundary particles, applying dynamic boundary conditions, and updating stress properties of the boundary particles according to the through state of the slip plane to obtain a model state containing seismic dynamic response; and S5, based on the model state, solving a momentum equation in parallel through the GPU to update the speed and the