A method, system and electronic device for evaluating nonlinear wave-induced seabed cumulative liquefaction based on a meshless method
The fluid and seabed model are established through the gridless method to calculate the seabed liquefaction area, which solves the problems of high calculation cost and insufficient accuracy in the seabed liquefaction evaluation of traditional grid methods, and achieves efficient and accurate seabed liquefaction evaluation.
Patent Information
- Application Number
- CN202310393358.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-04-13
- Publication Date
- 2025-04-08
- Estimated Expiration
- 2043-04-13
AI Technical Summary
Traditional grid-based numerical methods are costly and computationally expensive in grid generation and reconstruction, making it difficult to accurately describe the internal deformation of seabed soil under the action of nonlinear waves.
The local radial basis function dot-free grid method is used to establish a fluid model and seabed model, combining wave load characteristic parameters and seabed parameters, the bed dynamic pressure and seabed dynamic response information during wave dynamic propagation are calculated to predict the liquefied area of the seabed.
Accurate prediction of the response of wave-induced soil in the seabed is achieved, reducing calculation costs and time, and improving calculation efficiency and accuracy.
Smart Images
Figure CN116486948B_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of seabed soil liquefaction analysis, and specifically relates to an evaluation method, system and electronic equipment for nonlinear wave-induced cumulative liquefaction of a seabed based on a gridless method. Background Art
[0002] Seabed liquefaction is one of the important factors threatening seabed instability. Seabed soil is a typical two-phase porous medium. The cyclic shearing action of wave loads will increase the pore water pressure in the seabed, the effective stress of the soil skeleton will disappear, and liquefaction will occur. Once liquefaction occurs, the soil particles will show fluid characteristics, and the seabed foundation will lose its bearing capacity, causing the foundation of surrounding structures to be damaged, threatening the safety of the structures.
[0003] According to the way pore pressure is generated, the seabed response can be divided into two modes, namely transient response and cumulative response. The seabed soil is subjected to cyclic shearing action of waves. When the permeability coefficient of the soil is relatively small, the pore water pressure inside the soil skeleton has no time to dissipate. When the pore water pressure gradually accumulates and exceeds the stress of the overlying soil, cumulative liquefaction occurs. The second response mechanism is related to the wave phase. Under the trough, an upward seepage force is generated inside the soil. When the upward force exceeds the weight of the soil, transient liquefaction occurs. Based on the calculation idea of considering the coupling effect of stress development and pore pressure accumulation of transient response, a seabed cumulative liquefaction assessment method considering the inertia force of soil particles is proposed.
[0004] In this evaluation method, most of the numerical simulations of nonlinear wave-to-seabed cumulative liquefaction use traditional grid methods, such as the finite element method, the finite volume method, etc. However, traditional grid-based numerical methods have high costs in grid generation and reconstruction. The Local Radial Basis Function Collocation Method (LRBFCM) uses point-based approximation to completely eliminate the grid, which not only ensures the accuracy of the calculation, but also has good solution convergence. The discretization process is only related to the distance between the scattered points, and can accurately describe the internal deformation of the seabed soil under the action of nonlinear waves. Summary of the invention
[0005] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method, system and electronic equipment for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on a meshless method, aiming to solve the following technical problems in the prior art:
[0006] Traditional grid-based numerical methods have high costs in grid generation and reconstruction, and the amount of calculation is relatively large. The local radial basis function point-matching type gridless method adopted in the present invention adopts point-based approximation, which can completely eliminate the grid. It can not only ensure the accuracy of the calculation, but also have good solution convergence. The discrete process is only related to the distance between the scattered points, and can accurately describe the internal deformation problem of the seabed soil under the action of nonlinear waves.
[0007] The present invention is implemented by the following technical solutions:
[0008] The first aspect of the present invention provides a method for evaluating nonlinear wave-induced seabed cumulative liquefaction based on a meshless method, comprising the following steps:
[0009] Collect wave load characteristic parameters and seabed parameters;
[0010] Establish a fluid model and calculate the dynamic pressure of the bed surface during the dynamic propagation of waves by combining the characteristic parameters of wave loads;
[0011] Establish a seabed model, and calculate the dynamic response information of the seabed under the action of waves by combining seabed parameters and the dynamic pressure of the bed surface during wave dynamic propagation;
[0012] The liquefaction area of the seabed is predicted based on the dynamic response information of the seabed.
[0013] To optimize the above technical solutions, the specific measures taken also include:
[0014] Furthermore, the wave load characteristic parameters include wave height H, water depth d, wavelength L and period T, and the seabed parameters include soil shear modulus G, soil density ρ s , soil saturation S r , soil permeability coefficient K, soil porosity n s , relative density D r , Poisson's ratio e, seabed depth z.
[0015] Furthermore, a fluid model is established, and the dynamic pressure of the bed surface during the dynamic propagation of waves is calculated in combination with the characteristic parameters of wave loads. Specifically:
[0016] Use VARANS equations to model the fluid flow for the governing equations.
[0017]
[0018] Where: u i is the fluid velocity vector, ρ f is the fluid density, t is the time, n is the ratio of the fluid volume to the total volume, p * is the fluid dynamic pressure, g i is the acceleration due to gravity, μ effis the effective dynamic viscosity, A is the linear term in the porous medium, B is the nonlinear term in the porous medium, and C is the unsteady flow term in the porous medium;
[0019] According to the wave information and combined with the fluid model, the dynamic pressure inside the fluid during the wave dynamic propagation process is calculated;
[0020] The dynamic pressure p of the bed surface is extracted from the dynamic pressure inside the fluid using the numerical interpolation method. b .
[0021] Furthermore, a seabed model is established, and the dynamic response information of the seabed under the action of waves is calculated by combining the seabed parameters and the dynamic pressure of the bed surface during the dynamic propagation of waves. Specifically:
[0022] Based on the Biot up method, the coupled accumulation model of stress development and pore pressure is derived.
[0023] The seabed model is established using the coupled accumulation model as the governing equation;
[0024] The local radial basis function collocation type meshless method is used to discretize the seabed model and calculate the dynamic response information of the seabed under wave action.
[0025] Furthermore, the coupling accumulation model derived based on the Biot up method is:
[0026]
[0027] Where: σ′ x represents the effective stress in the horizontal direction, x is the horizontal direction and the horizontal right direction is the positive direction, z is the vertical direction and the vertical upward direction is the positive direction, τ xz represents shear stress, p s is the pore water pressure, ρ is the density of the porous medium, u s is the horizontal displacement of the soil, σ′ z is the effective stress in the vertical direction, w s is the vertical displacement of the soil, P is the pore water pressure, γ w is the unit weight of water, β s is the pore fluid compressibility, K w is the bulk elastic modulus of the pore fluid, P wo is the absolute pressure of water, m v is the volume compressibility coefficient, u g is the generated pore water pressure, σ0′ is the initial average effective stress, τ max is the cyclic shear stress amplitude, α and β are dimensionless fitting coefficients related to soil type and relative density.
[0028] Furthermore, the local radial basis function collocation type meshless method is used to discretize the seabed model and calculate the dynamic response information of the seabed under the action of waves, specifically:
[0029] The approximate function Φ(y i ), y j (j=1,2,…,n) is a sequence of points with arbitrary distribution;
[0030] Using radial basis B(r m ) in y i Construct a linear equation around each point:
[0031]
[0032] Among them, α m is χ(r m ) of the undetermined coefficient, r m is the distance between any two points, c is the shape parameter;
[0033] Select boundary conditions, use the seabed model, combine the bed surface dynamic pressure and seabed parameters, and calculate the seabed dynamic response information at each time step. The boundary conditions include pressure boundary conditions and displacement boundary conditions. The seabed dynamic response information includes the internal displacement of the soil and the pore water pressure under wave load.
[0034] Furthermore, the liquefaction area of the seabed is predicted based on the seabed dynamic response information, specifically:
[0035] Calculate the cumulative response of the seabed at each time step, the cumulative response of the seabed includes the effective stress and pore water pressure in the soil; calculate the liquefaction depth and width of the seabed soil according to the liquefaction criterion,
[0036] -γ′z≤(ps-pb)
[0037] Where: γ′ is the buoyancy weight of the seabed soil, z represents the depth of the seabed, p s is the pore water pressure, pb is the seabed surface wave pressure;
[0038] The maximum liquefaction area of the soil in the entire time history is calculated based on the liquefaction depth and width of the seabed soil at each time step.
[0039] The second aspect of the present invention provides an evaluation system for nonlinear wave-induced seabed cumulative liquefaction based on a meshless method, comprising:
[0040] Collection module 1, used to collect wave load characteristic parameters;
[0041] Collection module 2, used to collect seabed parameters;
[0042] Modeling module 1 is used to establish a fluid model and calculate the dynamic pressure of the bed surface during the dynamic propagation of waves in combination with the characteristic parameters of wave loads;
[0043] Modeling module 2 is used to establish a seabed model and calculate the dynamic response information of the seabed under the action of waves by combining seabed parameters and the dynamic pressure of the bed surface during the dynamic propagation of waves;
[0044] The analysis module is used to predict the liquefaction area of the seabed based on the dynamic response information of the seabed.
[0045] The third aspect of the present invention provides an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the above-mentioned method for evaluating nonlinear wave-induced seabed cumulative liquefaction based on the gridless method.
[0046] Beneficial effects of the present invention:
[0047] Compared with the prior art, the present invention is a method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on the gridless method. It takes into account the stress development of the instantaneous response and the cumulative coupling effect of the pore pressure. Based on the Biot partial dynamic model, it takes into account the influence of the acceleration of soil particles on the cumulative response, and can accurately predict the wave-induced seabed soil response. A one-way coupled data transmission is established between the fluid model and the seabed soil model. The seabed surface hydrodynamic pressure calculated by the fluid part sub-model at any time period can be applied to the soil model to obtain the seabed response, including the effective stress, displacement and pore water pressure of the soil skeleton in the seabed. This makes it easier to predict the cumulative liquefaction of the seabed caused by nonlinear waves according to the liquefaction judgment criteria. BRIEF DESCRIPTION OF THE DRAWINGS
[0048] Figure 1 It is a flow chart of a method for evaluating nonlinear wave-induced seabed cumulative liquefaction based on a gridless method provided by the present invention.
[0049] Figure 2 It is a detailed diagram of the process provided by the present invention.
[0050] Figure 3 It is a schematic diagram of the calculation domain provided by the present invention.
[0051] Figure 4 It is a schematic diagram of the liquefaction range of seabed soil provided by the present invention.
[0052] Figure 5 This is a module connection relationship diagram provided by the present invention.
[0053] Figure 6 The present invention is a schematic diagram of the structure of an electronic device. DETAILED DESCRIPTION
[0054] In order to illustrate the technical solution and working principle of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.
[0055] First embodiment
[0056] The present invention provides Figure 1-2 A method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on a meshless method is shown, comprising the following steps:
[0057] Step S1: Collect wave load characteristic parameters and seabed parameters.
[0058] Specifically, the characteristic parameters of wave load include wave height H, water depth d, wavelength L and period T, and the seabed parameters include soil shear modulus G, soil density ρs, soil saturation Sr, soil permeability coefficient K s , soil porosity ns, relative density Dr, Poisson's ratio e, and seabed depth z.
[0059] Step S2: Establish a fluid model and calculate the dynamic pressure of the bed surface during the dynamic propagation of waves in combination with the characteristic parameters of wave loads.
[0060] S21: Use VARANS equations to build a fluid model for the control equations.
[0061]
[0062]
[0063] Where: u i is the fluid velocity vector, ρ f is the fluid density, t is the time, n is the ratio of the fluid volume to the total volume, p * is the fluid dynamic pressure, g i is the acceleration due to gravity, μ eff is the effective dynamic viscosity, A is the linear term in the porous medium, B is the nonlinear term in the porous medium, and C is the unsteady flow term in the porous medium;
[0064] S22: Based on the wave information and combined with the fluid model, the dynamic pressure inside the fluid during the wave dynamic propagation process is calculated;
[0065] S23: The dynamic pressure of the bed surface pb is extracted from the dynamic pressure inside the fluid using a numerical interpolation method.
[0066] Step S3: Establish a seabed model, and calculate the dynamic response information of the seabed under the action of waves by combining seabed parameters and the dynamic pressure of the bed surface during the dynamic propagation of waves.
[0067] By building a seabed model and using it to calculate the dynamic response information of the seabed under wave action, and using the coupling model of transient response stress development and pore water pressure accumulation as the control equation, the dynamic response of the seabed under wave action can be simulated more finely and quickly, so as to make a more accurate assessment of the scope of seabed liquefaction.
[0068] S31: Based on the Biot up method, the coupled accumulation model of stress development and pore pressure is derived.
[0069]
[0070] Where: ′ x represents the effective stress in the horizontal direction, x is taken as the horizontal rightward direction as the positive direction, z is taken as the vertical upward direction as the positive direction, τ xz represents shear stress, p s is the pore water pressure, ρ is the density of the porous medium, u s The soil in the horizontal direction
[0071] ′ displacement, σ z is the effective stress in the vertical direction, w s is the vertical displacement of the soil, P is the pore water pressure, γ w is the unit weight of water, β s is the pore fluid compressibility, K w is the bulk elastic modulus of the pore fluid, Pwo is the absolute pressure of water, m v is the volume compressibility coefficient, u g is the generated pore water pressure, σ0′ is the initial average effective stress, τmax is the cyclic shear stress amplitude, and α and β are dimensionless fitting coefficients related to soil type and relative density.
[0072] S32: Establishing the seabed model using the coupled accumulation model as the control equation;
[0073] S33: The local radial basis function collocation type meshless method is used to discretize the seabed model and calculate the dynamic response information of the seabed under the action of waves:
[0074] S331: Establish an approximate function Φ(y i ), y j (j=1,2,…,n) is a sequence of points with arbitrary distribution;
[0075] S332: Using radial basis B(r m ) in yi Construct a linear equation around each point:
[0076]
[0077] Where: α m is χ(r m ) of the undetermined coefficient, r m is the distance between any two points, c is the shape parameter.
[0078] S33: Select boundary conditions, use the seabed model, combine the bed surface dynamic pressure and seabed parameters, and calculate the seabed dynamic response information of multiple time steps, wherein the boundary conditions include pressure boundary conditions and displacement boundary conditions. The seabed dynamic response information includes the internal displacement of the soil and the pore water pressure under wave load.
[0079] Step S4: predicting the liquefied area of the seabed according to the seabed dynamic response information.
[0080] S41: Calculate the cumulative response of the seabed at each time step, where the cumulative response of the seabed includes effective stress and pore water pressure in the soil;
[0081] S42: Calculate the liquefaction depth and width of the seabed soil according to the liquefaction criterion.
[0082] -γ′z≤(ps-pb)
[0083] Where: γ′ is the seabed buoyancy, z represents the seabed depth, p s is the pore water pressure, and pb is the seabed surface wave pressure.
[0084] S43: Calculate the maximum liquefaction area of the soil in the entire time history based on the liquefaction depth and width of the seabed soil at each time step.
[0085] Compared with the existing technology, this method considers the stress development of transient response and the cumulative coupling effect of pore pressure, and describes the cumulative response of the seabed more accurately. Based on the Biot partial dynamic equation, this model is more suitable for the general case of wave-induced cumulative response of the seabed than the existing technology. The meshless method is used for calculation, which has high computational efficiency, short time and small computational space compared with traditional numerical methods. Specific embodiment:
[0087] The collected wave information and seabed parameters include: the selected sea area has a water depth of 10m, a wave height of 3m, a wavelength of 39m, a period of 5s, and a soil shear modulus G of 8*10 6 Pa, soil density is 2650kg / m 3 , soil saturation is 1, soil permeability coefficient is 10 -4m / s, soil porosity is 0.42, relative density is 0.3, and Poisson's ratio e is 0.29. The calculation process is as follows Figure 2 The calculation domain diagram is shown in Figure 3 As shown, the wave propagates on the seabed along the positive direction of the x-axis, and vertically upward is the positive direction of the z-axis.
[0088] Input the required wave parameters into the wave model, select the wave type and run the fluid model, calculate the wave field, obtain the bed surface wave pressure in the calculation result and input it into the seabed model, input the collected seabed parameters into the seabed model, run the seabed model, obtain the pore water pressure and effective stress distribution inside the seabed, analyze the calculation results according to the liquefaction criterion, and get the following Figure 4 The figure shows the range of the liquefaction zone at the 20th, 40th, 70th and 100th wave cycles of the seabed. It can be seen from the figure that the liquefaction zone develops downward from the seabed surface. As time goes by, the range of the liquefaction zone gradually expands at first and then tends to stabilize.
[0089] The step division of the above methods is only for the purpose of clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent; adding insignificant modifications to the algorithm or process or introducing insignificant designs without changing the core design of the algorithm and process are all within the scope of protection of this patent.
[0090] Second implementation method:
[0091] like Figure 5 As shown, the second embodiment of the present invention provides an evaluation system for nonlinear wave-induced seabed cumulative liquefaction based on a meshless method, comprising:
[0092] A collection module 201 is used to collect wave load characteristic parameters;
[0093] The second acquisition module 202 is used to acquire seabed parameters;
[0094] A modeling module 1 203 is used to establish a fluid model and calculate the dynamic pressure of the bed surface during the dynamic propagation of waves in combination with characteristic parameters of wave loads;
[0095] Modeling module 2 204 is used to establish a seabed model and calculate the dynamic response information of the seabed under the action of waves by combining seabed parameters and the dynamic pressure of the bed surface during the dynamic propagation of waves;
[0096] The analysis module 205 is used to predict the liquefied area of the seabed according to the dynamic response information of the seabed.
[0097] It is not difficult to find that this embodiment is a system embodiment corresponding to the first embodiment, and this embodiment can be implemented in conjunction with the first embodiment. The relevant technical details mentioned in the first embodiment are still valid in this embodiment, and in order to reduce repetition, they are not repeated here. Accordingly, the relevant technical details mentioned in this embodiment can also be applied in the first embodiment.
[0098] It is worth mentioning that all modules involved in this embodiment are logic modules. In practical applications, a logic unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. In addition, in order to highlight the innovative part of the present invention, this embodiment does not introduce units that are not closely related to solving the technical problem proposed by the present invention, but this does not mean that there are no other units in this embodiment.
[0099] Third embodiment:
[0100] like Figure 6 As shown, the third embodiment of the present invention provides an electronic device, comprising: at least one processor 301; and a memory 302 communicatively connected to the at least one processor 301; wherein the memory 302 stores instructions executable by the at least one processor 301, and the instructions are executed by the at least one processor 301 so that the at least one processor 301 can execute the above-mentioned method for evaluating nonlinear wave-induced seabed cumulative liquefaction based on the gridless method.
[0101] The memory 302 and the processor 301 are connected in a bus manner, and the bus may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors 301 and the memory 302 together. The bus can also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on a transmission medium. The data processed by the processor 301 is transmitted on a wireless medium through an antenna, and further, the antenna also receives data and transmits the data to the processor 301.
[0102] The processor 301 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management and other control functions. The memory 302 can be used to store data used by the processor 301 when performing operations.
[0103] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.
Claims
1. A method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on a meshless method, characterized in that: The following steps are involved: Collect wave load characteristic parameters and seabed parameters; Establish a fluid model and calculate the dynamic pressure of the bed surface during the dynamic propagation of waves by combining the characteristic parameters of wave loads; Establish a seabed model, and calculate the dynamic response information of the seabed under the action of waves by combining seabed parameters and the dynamic pressure of the bed surface during wave dynamic propagation; specifically: Based on the Biot up method, the coupled accumulation model of stress development and pore pressure is derived; τ xz represents shear stress, p s is the pore water pressure, ρ is the density of the porous medium, u s is the horizontal displacement of the soil, σ′ z is the effective stress in the vertical direction, w s is the vertical displacement of the soil, P is the pore water pressure, γ w is the unit weight of water, β s is the pore fluid compressibility, K w is the bulk elastic modulus of the pore fluid, P wo is the absolute pressure of water, m v is the volume compressibility coefficient, u g is the generated pore water pressure, σ0′ is the initial average effective stress, τ max is the cyclic shear stress amplitude, α and β are dimensionless fitting coefficients related to soil type and relative density; The seabed model is established using the coupled accumulation model as the governing equation; The local radial basis function collocation type meshless method is used to discretize the control equations and calculate the dynamic response information of the seabed under the action of waves. The liquefaction area of the seabed is predicted based on the dynamic response information of the seabed.
2. The method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on the meshless method according to claim 1 is characterized by: The wave load characteristic parameters include wave height H, water depth d, wavelength L and period T, and the seabed parameters include soil shear modulus G, soil density ρ s , soil saturation S r , soil permeability coefficient K s , soil porosity n s , relative density D r , Poisson's ratio e, seabed depth z.
3. The method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on the meshless method according to claim 2 is characterized in that: A fluid model is established, and the dynamic pressure of the bed surface during the dynamic propagation of waves is calculated in combination with the characteristic parameters of wave loads. Specifically: Use VARANS equations to model the fluid flow for the governing equations. Where: u i is the fluid velocity vector, ρ f is the fluid density, t is the time, n is the ratio of the fluid volume to the total volume, P * is the fluid dynamic pressure, g i is the acceleration due to gravity, μ eff is the effective dynamic viscosity, A is the linear term in the porous medium, B is the nonlinear term in the porous medium, and C is the unsteady flow term in the porous medium; According to the wave information and combined with the fluid model, the dynamic pressure inside the fluid during the wave dynamic propagation process is calculated; The dynamic pressure p of the bed surface is extracted from the dynamic pressure inside the fluid using the numerical interpolation method. b .
4. The method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on the meshless method according to claim 3 is characterized in that: The local radial basis function collocation type meshless method is used to discretize the control equations of the seabed model and calculate the dynamic response information of the seabed under the action of waves, specifically: The approximate function Φ(y i ), y j (j=1,2,…,n) is a sequence of points with arbitrary distribution; Using radial basis B(r m ) in y i Construct a linear equation around each point: Among them, α m is χ(r m ) of the undetermined coefficient, r m is the distance between any two points, c is the shape parameter; Select boundary conditions, use the seabed model, combine the bed surface dynamic pressure and seabed parameters, and calculate the seabed dynamic response information at each time step. The boundary conditions include pressure boundary conditions and displacement boundary conditions. The seabed dynamic response information includes the internal displacement of the soil and the pore water pressure under wave load.
5. The method for evaluating the cumulative liquefaction of the seabed caused by nonlinear waves based on the meshless method according to claim 4, characterized in that: The liquefaction area of the seabed is predicted based on the dynamic response information of the seabed, specifically: Calculating the cumulative response of the seabed at each time step, wherein the cumulative response of the seabed includes effective stress and pore water pressure in the soil; According to the liquefaction criterion, the liquefaction depth and width of the seabed soil are calculated. -γ′z≤(p s -p b ) Where: γ′ is the buoyancy weight of the seabed soil, z represents the depth of the seabed, p s is the pore water pressure, p b is the seabed surface wave pressure; The maximum liquefaction area of the soil in the entire time history is calculated based on the liquefaction depth and width of the seabed soil at each time step.
6. A nonlinear wave-induced seabed cumulative liquefaction assessment system based on a meshless method, characterized by: include, Collection module 1, used to collect wave load characteristic parameters; Collection module 2, used to collect seabed parameters; Modeling module 1 is used to establish a fluid model and calculate the dynamic pressure of the bed surface during the dynamic propagation of waves in combination with the characteristic parameters of wave loads; Modeling module 2 is used to establish a seabed model and calculate the dynamic response information of the seabed under the action of waves by combining seabed parameters and the dynamic pressure of the bed surface during the dynamic propagation of waves; specifically: Based on the Biot up method, the coupled accumulation model of stress development and pore pressure is derived; τ xz represents shear stress, p s is the pore water pressure, ρ is the density of the porous medium, u s is the horizontal displacement of the soil, σ′ z is the effective stress in the vertical direction, w s is the vertical displacement of the soil, P is the pore water pressure, γ w is the unit weight of water, β s is the pore fluid compressibility, K w is the bulk elastic modulus of the pore fluid, P wo is the absolute pressure of water, m v is the volume compressibility coefficient, u g is the generated pore water pressure, σ0′ is the initial average effective stress, τ max is the cyclic shear stress amplitude, α and β are dimensionless fitting coefficients related to soil type and relative density; The analysis module is used to predict the liquefaction area of the seabed based on the dynamic response information of the seabed.
7. An electronic device, characterized in that: include: at least one processor; And, a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute a method for evaluating nonlinear wave-induced seabed cumulative liquefaction based on a gridless method as described in any one of claims 1-5.