Finite element-based seismic toughness assessment method and system for high-piled piers

Abstract

The present invention provides a finite element-based seismic toughness assessment method and system for a high-pile wharf, which relates to the technical field of high-pile wharves. The present invention first constructs a finite element soil model and a finite element wharf model at the high-pile wharf, and forms a finite element coupling model after coupling to simulate earthquake conditions under real conditions. After applying simulated seismic waves to the finite element coupling model, the damage to the soil under the action of the seismic waves, the damage index of the wharf, the energy dissipation of the wharf, and the ductility coefficient of the wharf are analyzed respectively. The damage index, energy dissipation, and ductility coefficient are respectively used to evaluate the damage degree, energy absorption and consumption capacity, deformation capacity, and ductility of the wharf, and the analyzed parameters are fitted and analyzed to generate a comprehensive toughness evaluation index for reflecting the seismic resistance of the high-pile wharf. Finally, the seismic resistance grade of the wharf structure is output to assist staff in completing the seismic toughness assessment of the wharf, greatly saving work efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of high-pile docks, and in particular to a finite element-based method and system for evaluating the seismic toughness of high-pile docks. Background Art

[0002] As a crucial component of port infrastructure, high-pile piers are widely used in deepwater berths and heavy-load operating environments. They are primarily composed of numerous pile foundations and caps, which transmit loads to the underlying soil, ensuring the pier's stability and carrying capacity. Due to their high height, complex load-bearing conditions, and the environment often subject to extreme loads such as earthquakes, high-pile piers are susceptible to significant structural deformation or even damage in these conditions, threatening the safe operation of the pier and port operations.

[0003] At present, the seismic performance evaluation of high-pile piers is often based on the principles of static mechanics, analyzing stress and strain parameters to determine whether the seismic resistance meets the standards. This method has a certain degree of simplicity and is difficult to accurately reflect the complex interaction between the structure and the soil and its elastic-plastic behavior, resulting in great uncertainty in the evaluation of seismic toughness.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a finite element-based method and system for evaluating the seismic toughness of a high-piled pier, so as to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The finite element-based seismic toughness assessment method for high-piled piers includes the following steps:

[0008] S1. Collect pile foundation structural and material parameters, build a three-dimensional structural model based on finite element software, and couple the elastic-plastic constitutive characteristics of the high-piled pier to generate a finite element pier model to simulate the mechanical behavior of the pier structure in the elastic and plastic stages;

[0009] S2. Collect soil mechanical parameters and interface parameters, input the soil mechanical parameters and interface parameters into finite element software, generate a finite element soil model, couple the finite element soil model with the finite element wharf model, and generate a finite element coupling model for comprehensive simulation of the interaction between the wharf structure and the soil;

[0010] S3. Generate simulated seismic waves based on historical earthquake data, apply the simulated seismic waves to the finite element coupling model, analyze the natural frequency of the high-pile pier and generate the maximum displacement and maximum vibration velocity of the high-pile pier; generate the maximum shear stress of the soil based on the simulated seismic waves and soil mechanical parameters and critical shear strength of soil failure ;

[0011] S4, when the soil has the maximum shear stress Greater than the critical shear strength of soil failure When the output comprehensive toughness evaluation index ZPR is 0, the maximum shear stress of the soil is Less than the critical shear strength of soil failure When , execute steps S5 and S6;

[0012] S5. Based on the finite element coupling model, the yield displacement and ultimate displacement are generated through correlation analysis, and then the ductility coefficient is calculated ; Perform correlation analysis on maximum vibration velocity and seismic wave time to generate energy dissipation Analyze the stiffness of the finite element coupling model after coupling simulated seismic waves, and further perform correlation analysis based on the stiffness to generate the damage index D;

[0013] S6. Conduct correlation analysis on the ductility coefficient, energy dissipation, and damage index to generate a comprehensive toughness evaluation index ZPR; compare the comprehensive toughness evaluation index ZPR with the threshold value to output the seismic resistance grade of the wharf structure.

[0014] Furthermore, the pile foundation structural parameters include pile diameter, pile length, and pile cap size; the pile foundation material parameters include the elastic modulus of the pier. , Poisson's ratio of the pier, yield strength of the pier , Pier yield strain The pile diameter d is the cross-sectional diameter of the pile of the high-pile wharf, the pile length L is the depth of the pile, and the platform size includes length, width and height, which are used to construct the three-dimensional model of the high-pile wharf. The elastic modulus of the wharf is is the elastic modulus of the high-pile pier, Poisson's ratio Used to reflect the lateral deformation characteristics of high-pile piers under axial stress, the pier yield strength The critical stress at which the three-dimensional model of the high-piled pier begins to produce plastic deformation, and the pier yield strain is the strain value of the pier yield strength, where .

[0015] Furthermore, the elastic modulus of the pier , Pier yield strength , Pier yield strain Correlation analysis is performed to construct the elastoplastic constitutive characteristics of the high-pile wharf based on the following formula:

[0016] ;

[0017] in, is the hardening modulus of the high-pile wharf, is the strain of the high-pile pier. The elastoplastic constitutive characteristics of the high-pile pier are used to reflect the relationship between the strain and stress of the high-pile pier.

[0018] Furthermore, the soil mechanical parameters include soil depth, soil density, internal friction angle, cohesion, soil elastic modulus, soil Poisson's ratio, and particle diameter; the interface parameters include interface friction angle and bond strength; the soil depth h is the depth of the piles of the high-pile wharf inserted into the soil, and the particle diameter is the average diameter of the soil particles in the area where the high-pile pier is located, and the earthquake wave is simulated to interfere with the finite element coupling model. The duration of the earthquake wave is T, and the peak acceleration is A. The stiffness k of the finite element coupling model and the mass m of the high-pile pier are analyzed for correlation, and the natural frequency of the high-pile pier is generated. It is used to reflect the frequency of natural vibration of high-pile piers without external excitation, conduct correlation analysis on the natural frequency of high-pile piers, and generate the maximum displacement of high-pile piers. , and generate the maximum vibration speed of the high-pile pier , based on the formula: ;

[0019] The correlation analysis between seismic waves and soil mechanical parameters is performed to generate the maximum shear stress of the soil and the critical shear strength of soil failure. The formula is: ;

[0020] in, is the equivalent acceleration ratio caused by seismic waves under unit gravity, , is the maximum shear stress of the soil, which is used to reflect the maximum shear force of the soil under the influence of simulated seismic waves, h is the depth of the soil, is the soil density, is the critical shear strength of soil failure, which is used to reflect the ultimate shear stress value of soil resisting shear failure. is the soil cohesion, is the effective stress of soil, , g is the acceleration due to gravity, is the internal friction angle, when When the soil is severely damaged under the simulated earthquake wave condition, it cannot support the high-pile pier. At this time, the comprehensive toughness evaluation index ZPR is set to 0.

[0021] Furthermore, a horizontal thrust F is applied to the pile top of the finite element coupling model, so that the finite element coupling model is in the elastic stage and the soil does not suffer nonlinear damage, and the displacement of the point where the horizontal thrust is applied is obtained. , according to the formula , the stiffness k value of the finite element coupling model is obtained through fitting analysis.

[0022] Furthermore, a load is applied to the finite element coupling model and the load is gradually increased to obtain displacement data. The yield displacement and ultimate displacement are determined by the offset method. The yield displacement The displacement corresponding to the plastic deformation of the three-dimensional model part of the finite element coupling model begins, and the limit displacement The maximum load-bearing deformation of the three-dimensional model of the finite element coupling model is obtained by performing a correlation analysis between the yield displacement and the ultimate displacement to generate the ductility coefficient based on the following formula:

[0023] ;

[0024] Perform correlation analysis on maximum vibration velocity and seismic waves to generate energy dissipation , based on the formula:

[0025] ;

[0026] Among them, the ductility coefficient is used to reflect the deformation capacity and ductility of the structure under earthquake action, energy dissipation It is the energy that is no longer stored in a recoverable elastic form when the finite element coupling model converts the input mechanical energy into other forms of energy during the load deformation process. Energy dissipation is used to reflect the energy absorption and consumption capacity of the structure during an earthquake. is the structural stress of the wharf, ;

[0027] The stiffness k of the finite element coupling model is subjected to correlation analysis to generate the damage index D, based on the following formula:

[0028] ;

[0029] The damage index D is used to reflect the damage degree of the high-pile pier after the earthquake wave. is the stiffness of the finite element coupling model after the seismic wave, based on the formula:

[0030] ;

[0031] in, is the reaction force variation of the pile support in the unloading section of the finite element coupling model, is the displacement change of the pile foundation support in the unloading section of the finite element coupling model.

[0032] Furthermore, the correlation analysis of ductility coefficient, energy dissipation and damage index is carried out to generate the comprehensive toughness evaluation index ZPR, based on the following formula:

[0033] ;

[0034] Comprehensive toughness evaluation index Used to reflect the seismic resistance of high-pile piers.

[0035] Furthermore, the seismic toughness evaluation index is used to reflect the overall seismic performance and toughness level of the structure, and the seismic grade is used to reflect the safety performance level of the structure under earthquake action. With threshold Compare and output the seismic grade of the wharf structure. When the seismic resistance level of the output terminal structure is level 2, the seismic resistance of the terminal structure is poor, and manual repair and maintenance of the terminal is required; when When the seismic resistance level of the output terminal structure is level one, the seismic resistance of the terminal structure is good and needs to be continued to be monitored.

[0036] The present invention provides a finite element-based seismic toughness assessment system for a high-pile pier, which is used to implement a finite element-based seismic toughness assessment method for a high-pile pier, including:

[0037] The wharf model construction module is used to collect pile foundation structural parameters and material parameters, build a three-dimensional structural model based on finite element software, and couple the elastic-plastic constitutive characteristics of the high-pile wharf to generate a finite element wharf model;

[0038] Comprehensive model building module, used to collect soil mechanical parameters and interface parameters, input soil mechanical parameters and interface parameters based on finite element software, generate finite element soil model, couple the finite element soil model with the finite element wharf model to generate finite element coupling model;

[0039] The seismic wave simulation module is used to generate simulated seismic waves based on historical seismic data, apply the simulated seismic waves to the finite element coupling model, analyze the natural frequency of the high-pile pier and generate the maximum displacement and maximum vibration velocity of the high-pile pier; based on the simulated seismic waves and soil mechanical parameters, the maximum shear stress of the soil is generated. and critical shear strength of soil failure ;

[0040] Preliminary output module for analyzing maximum shear stress in soil and critical shear strength of soil failure Size, output comprehensive toughness evaluation index ZPR or execute comprehensive analysis module and comprehensive output module according to the results;

[0041] Comprehensive analysis module, used to generate yield displacement and ultimate displacement through correlation analysis based on finite element coupling model, and then calculate ductility coefficient ; Perform correlation analysis on maximum vibration velocity and seismic wave time to generate energy dissipation Analyze the stiffness of the finite element coupling model after coupling simulated seismic waves, and further perform correlation analysis based on the stiffness to generate the damage index D;

[0042] The comprehensive output module is used to perform correlation analysis on the ductility coefficient, energy dissipation and damage index to generate a comprehensive toughness evaluation index ZPR; the comprehensive toughness evaluation index ZPR is compared with the threshold value to output the seismic resistance level of the wharf structure.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] The present invention first constructs a finite element soil model and a finite element wharf model at a high-pile wharf, and forms a finite element coupling model after coupling to simulate earthquake conditions under real conditions. After applying simulated seismic waves to the finite element coupling model, the damage to the soil under the action of the seismic waves, the damage index of the wharf, the energy dissipation of the wharf, and the ductility coefficient of the wharf are analyzed respectively. The damage index, energy dissipation, and ductility coefficient are respectively used to evaluate the damage degree, energy absorption and consumption capacity, deformation capacity, and ductility of the wharf. The analyzed parameters are fitted and analyzed to generate a comprehensive toughness evaluation index that reflects the seismic resistance of the high-pile wharf. Finally, the seismic resistance grade of the wharf structure is output to assist staff in completing the seismic toughness assessment of the wharf, greatly saving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 Schematic diagram of the overall method flow of the present invention;

[0046] Figure 2 This is a schematic diagram of the overall system module of the present invention;

[0047] Figure 3 is a fitting curve diagram of the ductility coefficient-comprehensive toughness evaluation index of the present invention;

[0048] Figure 4 It is a fitting curve diagram of the energy dissipation-comprehensive toughness evaluation index of the present invention;

[0049] Figure 5 This is a fitting curve diagram of the damage index-comprehensive toughness evaluation index of the present invention. DETAILED DESCRIPTION

[0050] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0051] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0052] Example:

[0053] See also Figure 1 , the present invention provides a technical solution:

[0054] The finite element-based seismic toughness assessment method for high-piled piers includes the following steps:

[0055] Step 1: Collect the pile foundation structural parameters and material parameters, build a three-dimensional structural model based on finite element software, and couple the elastic-plastic constitutive characteristics of the high-pile wharf to generate a finite element wharf model to simulate the mechanical behavior of the wharf structure in the elastic and plastic stages;

[0056] When constructing a finite element model, first create a three-dimensional model, divide the finite element mesh, define the material properties, apply simulated seismic waves and loads through ANSYS finite element analysis software, and then extract corresponding parameters such as displacement, stress, strain, reaction force, acceleration, etc.

[0057] Pile foundation structural parameters include the pile diameter, pile length, and platform size of the high-pile wharf; pile foundation material parameters include the elastic modulus of the high-pile wharf material , Poisson's ratio of the pier, yield strength of the pier , Pier yield strain The pile diameter d is the cross-sectional diameter of the pile of the high-pile wharf, the pile length L is the depth of the pile, and the platform size includes length, width and height, which are used to construct the three-dimensional model of the high-pile wharf. The elastic modulus of the wharf is is the elastic modulus of the high-pile pier, Poisson's ratio Used to reflect the lateral deformation characteristics of high-pile piers under axial stress, the pier yield strength The critical stress at which the three-dimensional model of the high-piled pier begins to produce plastic deformation, and the pier yield strain is the strain value of the pier yield strength, where ,The pile foundation material parameters are used to provide a static and dynamic analysis basis for the 3D model of the high-piled wharf.

[0058] Elastic modulus of the pier , Pier yield strength , Pier yield strain Correlation analysis is performed to construct the elastoplastic constitutive characteristics of the high-pile wharf based on the following formula:

[0059] ;

[0060] in, To predict the stress of the high-pile pier, the elastoplastic constitutive characteristics of the high-pile pier are used to reflect the relationship between the strain and stress of the high-pile pier, and are coupled to the three-dimensional model of the high-pile pier to generate a finite element pier model. is the hardening modulus of the high-pile wharf, The strain of high-pile docks.

[0061] This constitutive property reflects the continuity of the linear response of the high-pile wharf material in the elastic stage and the hardening behavior in the plastic stage. It can accurately reflect the stress changes of the material from elastic deformation to plastic deformation, accurately simulate the mechanical behavior of the wharf structure, and improve the prediction ability of deformation and damage.

[0062] Step 2: Collect soil layer mechanical parameters and interface parameters. Based on the finite element software and the three-dimensional model of the soil, input the soil layer mechanical parameters and interface parameters to generate a finite element soil model. The finite element soil model is coupled with the three-dimensional model of the finite element wharf model to generate a finite element coupling model for comprehensive simulation of the interaction between the wharf structure and the soil.

[0063] Soil layer mechanical parameters include soil depth, soil density, internal friction angle, cohesion, soil elastic modulus, soil Poisson's ratio, and particle diameter; interface parameters include interface friction angle and bond strength; soil depth h is the depth of the piles of the high-pile wharf inserted into the soil, and particle diameter is the average diameter of soil particles in the area where the high-pile wharf is located.

[0064] Step 3: Generate simulated seismic waves based on historical earthquake data, apply the simulated seismic waves to the three-dimensional model part of the finite element coupling model, analyze the natural frequency of the high-pile pier and generate the maximum displacement and maximum vibration velocity of the high-pile pier; generate the maximum shear stress of the soil based on the simulated seismic waves and soil mechanical parameters and critical shear strength of soil failure ;

[0065] Obtain historical earthquake data for the area where the high-pile pier is located. Based on the historical earthquake data, obtain the average earthquake wave duration and the average peak acceleration of the earthquake wave. Set the average duration of the historical earthquake wave as the duration of the simulated earthquake wave, and set the average peak acceleration of the historical earthquake wave as the peak acceleration of the simulated earthquake wave.

[0066] By simulating the interference of earthquake waves on the three-dimensional model of the finite element coupling model, the duration of the earthquake wave is T, the peak acceleration is A, and the correlation analysis of the stiffness k of the three-dimensional model of the finite element coupling model and the mass m of the high-pile pier is performed to generate the natural frequency of the high-pile pier. It is used to reflect the frequency of natural vibration of high-pile piers without external excitation, conduct correlation analysis on the natural frequency of high-pile piers, and generate the maximum displacement of high-pile piers. , and generate the maximum vibration speed of the high-pile pier , based on the formula: ;

[0067] Among them, the maximum displacement of the high-pile wharf is the maximum displacement distance of the high-pile pier under the action of simulated seismic waves, and the maximum vibration velocity of the high-pile pier is the maximum vibration velocity of the high-pile pier under the action of simulated seismic waves.

[0068] The natural frequency is the natural vibration frequency of a piled pier in the absence of external excitation and reflects the dynamic stiffness and mass distribution characteristics of the structure. The maximum displacement represents the maximum amplitude of the piled pier under simulated seismic excitation and is used to assess the degree of structural deformation. The stiffness k characterizes the piled pier's ability to resist deformation.

[0069] The correlation analysis between seismic waves and soil mechanical parameters is performed to generate the maximum shear stress of the soil and the critical shear strength of soil failure. The formula is: ;

[0070] Soil density, gravitational acceleration, and soil depth jointly determine the effective stress state of the soil. It is the equivalent acceleration ratio caused by the simulated seismic wave under unit gravity, which is used to reflect the ratio of the ground acceleration caused by the simulated seismic wave to the acceleration due to gravity. It directly reflects the relative strength of the ground acceleration caused by the earthquake and gravity, and directly affects the magnitude of the shear stress. , is the maximum shear stress of the soil, which is used to reflect the maximum shear force of the soil under the influence of simulated seismic waves, h is the depth of the soil, is the soil density, is the critical shear strength of soil failure, which is used to reflect the ultimate shear stress value of soil resisting shear failure. is the soil cohesion, is the effective stress of soil, , g is the acceleration due to gravity, is the internal friction angle. The maximum shear stress is positively correlated with soil density, depth, and earthquake acceleration ratio; the critical shear strength is positively correlated with soil cohesion, effective stress, and internal friction angle.

[0071] Step 4: When the soil has the maximum shear stress Greater than the critical shear strength of soil failure When the output comprehensive toughness evaluation index ZPR is 0, the output seismic grade of the wharf structure is level 2. At this time, the seismic resistance of the wharf structure is poor, and manual repair and maintenance of the wharf is required.

[0072] when When the maximum shear stress on the soil is greater than the critical shear strength of soil failure, it causes soil deformation. In this case, the soil is severely damaged and cannot support the high-pile wharf. At this time, the comprehensive toughness evaluation index ZPR is set to 0.

[0073] Maximum shear stress of soil Less than the critical shear strength of soil failure When , execute steps 5 and 6; that is, when When the maximum shear stress on the soil is not greater than the critical shear strength of soil failure, the soil is not seriously damaged. The finite element coupling model is further analyzed and steps 5 and 6 are executed.

[0074] Step 5: Based on the finite element coupling model, generate the yield displacement and ultimate displacement through correlation analysis, and then calculate the ductility coefficient ; Perform correlation analysis on maximum vibration velocity and seismic wave time to generate energy dissipation Analyze the stiffness of the three-dimensional model of the finite element coupling model after coupling simulated seismic waves, and further perform correlation analysis based on the stiffness to generate the damage index D;

[0075] Apply a horizontal thrust F to the pile top of the finite element coupling model, so that the finite element coupling model is in the elastic stage and the soil does not undergo nonlinear damage, and obtain the displacement of the point where the horizontal thrust is applied , according to the formula , and the stiffness k value of the finite element coupling model is obtained through linear fitting analysis.

[0076] Apply load to the finite element coupling model and increase the load gradually to obtain displacement data. The yield displacement and ultimate displacement are determined by the offset method. The displacement corresponding to the plastic deformation of the three-dimensional model part of the finite element coupling model begins, and the limit displacement The maximum load-bearing deformation of the three-dimensional model of the finite element coupling model is obtained by performing a correlation analysis between the yield displacement and the ultimate displacement to generate the ductility coefficient based on the following formula:

[0077] ;

[0078] The ductility coefficient reflects the deformation capacity and plastic deformation amplitude of the 3D model of the finite element coupled model after yielding. A larger value indicates better ductility and deformation capacity, and better ability to absorb earthquake energy. A larger yield displacement indicates a greater elastic deformation displacement of the 3D model of the finite element coupled model, and better ability to absorb earthquake energy. The ultimate displacement is the limit value of the 3D model of the finite element coupled model. The yield displacement and ultimate displacement reflect the deformation process of the 3D model of the finite element coupled model from the elastic stage to the ultimate load-bearing stage, and determine the magnitude of the ductility coefficient.

[0079] Perform correlation analysis on maximum vibration velocity and simulated seismic waves to generate energy dissipation , based on the formula:

[0080] ;

[0081] Among them, energy dissipation It is the energy that is converted from the input mechanical energy into other forms of energy during the load deformation process of the finite element coupling model, and is no longer stored in a recoverable elastic form. Energy dissipation is used to reflect the energy absorption and consumption capacity of the three-dimensional model of the finite element coupling model during the earthquake process. is the structural stress of the wharf, The greater the energy dissipation, the better the seismic toughness and damage resistance of the three-dimensional model of the finite element coupling model. The maximum vibration velocity is related to the response speed of the three-dimensional model of the finite element coupling model, which affects the size of its kinetic energy. The duration of the simulated seismic wave affects the length of time it is subjected to kinetic energy input. The greater the maximum stress, the stronger the dynamic load borne by the structure, and the greater the loading energy per unit time. The vibration velocity reflects the intensity of the structural movement. The greater the vibration velocity, the stronger the dynamic effect of the structural movement per unit time, the greater the energy conversion rate, and thus the energy dissipation. The longer the duration, the longer the dynamic loading process experienced by the structure, the more accumulated energy input, and the increase in the overall energy dissipation.

[0082] The stiffness k of the finite element coupling model is subjected to correlation analysis to generate the damage index D, based on the following formula:

[0083] ;

[0084] The damage index D is used to reflect the degree of damage to the high-pile pier after the simulated earthquake wave. A damage index D value close to 0 indicates that the stiffness of the three-dimensional model is well maintained and the structure is in good condition. A damage index D value close to 1 indicates a serious loss of stiffness and severe damage. It reflects the degradation of stiffness. The larger the value, the smaller the stiffness degradation and the slighter the loss of structural stiffness. The damage index is positively correlated with the stiffness degradation. If the stiffness decreases more after the simulated earthquake wave, the damage index is closer to 1. is the stiffness of the three-dimensional model of the finite element coupled model after the seismic wave, based on the formula:

[0085] ;

[0086] in, is the reaction force variation of the pile support in the unloading section of the finite element coupling model, The displacement change of the pile foundation support during the unloading section of the finite element coupling model. The reaction force change refers to the change in the support reaction force generated at the pile foundation support during the unloading process of the 3D finite element coupling model.

[0087] Table 1: Experimental statistical parameters

[0088]

[0089] Table 1 is a parameter statistical table of 30 groups of data from the statistical experiment. Groups 5, 10, 19, and 26 can intuitively reflect that higher ductility coefficients, higher energy dissipation, and lower damage indices correspond to higher comprehensive toughness evaluation indices. Groups 3, 9, 17, 24, and 30 have lower ductility coefficients, lower energy dissipation, or higher damage indices corresponding to lower comprehensive toughness evaluation indices. Figure 3 、 Figure 4 and Figure 5 They represent the curve fitting of ductility coefficient-comprehensive toughness evaluation index, energy dissipation-comprehensive toughness evaluation index and damage index-comprehensive toughness evaluation index, respectively, which intuitively demonstrates the positive correlation between ductility coefficient-comprehensive toughness evaluation index, energy dissipation-comprehensive toughness evaluation index and the negative correlation between damage index-comprehensive toughness evaluation index.

[0090] Step 6: Conduct a correlation analysis on the ductility coefficient, energy dissipation, and damage index to generate a comprehensive toughness evaluation index ZPR; compare the comprehensive toughness evaluation index ZPR with the threshold value to output the seismic resistance grade of the wharf structure.

[0091] Correlation analysis is performed on the ductility coefficient, energy dissipation, and damage index to generate the comprehensive toughness evaluation index ZPR. The formula is as follows:

[0092] ;

[0093] Comprehensive toughness evaluation index This comprehensive indicator reflects the seismic resistance of high-pile piers. It quantifies the seismic resilience of high-pile pier structures under earthquakes, taking into account the structure's ductility, energy dissipation capacity, and degree of damage. A larger value indicates greater structural resilience, meaning it can withstand greater deformation and absorb more seismic energy under earthquake loads while minimizing damage, demonstrating greater safety and continued serviceability. A smaller value indicates poor structural resilience, potentially posing a greater risk of damage.

[0094] The larger the ductility coefficient, the greater the deformation that the structure can withstand during an earthquake without brittle failure, and the better the toughness performance. The better the seismic resistance of the structure, the larger the comprehensive toughness evaluation index, which has a positive promoting effect on toughness, but its influence has a decreasing marginal effect, so the ductility coefficient is in the form of a square root in the formula. The greater the energy dissipation, the stronger the structure's ability to absorb and consume earthquake energy, which can effectively reduce earthquake damage and improve structural toughness. That is, the better the seismic resistance of the structure, the larger the comprehensive toughness evaluation index. In the formula, This reflects the positive effect of energy dissipation on toughness. A logarithmic function is used to demonstrate the decreasing effect of energy dissipation on toughness, preventing the toughness index from increasing infinitely when energy dissipation is excessive. A larger value for the damage index, D, indicates greater structural damage, weaker seismic resistance, poorer toughness, and a smaller comprehensive toughness evaluation index. The damage index and comprehensive toughness evaluation index are negatively correlated.

[0095] The seismic resistance grade is used to reflect the safety performance level of the structure under earthquake action. The threshold value refers to the critical value used to distinguish the seismic toughness level of the structure. Based on experimental data, the critical threshold value of the performance level is determined by statistical analysis method, and the comprehensive toughness evaluation index is used to evaluate the performance level. With threshold Compare and output the seismic grade of the wharf structure. When the seismic resistance level of the output terminal structure is level 2, the seismic resistance of the terminal structure is poor, and manual repair and maintenance of the terminal is required; when When the seismic resistance level of the output terminal structure is level one, the seismic resistance of the terminal structure is good and needs to be continued to be monitored.

[0096] Reference Figure 2 The present invention provides a finite element-based seismic toughness assessment system for a high-pile pier, which is used to implement a finite element-based seismic toughness assessment method for a high-pile pier, including:

[0097] The wharf model construction module is used to collect pile foundation structural parameters and material parameters, build a three-dimensional structural model based on finite element software, and couple the elastic-plastic constitutive characteristics of the high-pile wharf to generate a finite element wharf model;

[0098] Comprehensive model building module, used to collect soil mechanical parameters and interface parameters, input soil mechanical parameters and interface parameters based on finite element software, generate finite element soil model, couple the finite element soil model with the finite element wharf model to generate finite element coupling model;

[0099] The seismic wave simulation module is used to generate simulated seismic waves based on historical seismic data, apply the simulated seismic waves to the finite element coupling model, analyze the natural frequency of the high-pile pier and generate the maximum displacement and maximum vibration velocity of the high-pile pier; based on the simulated seismic waves and soil mechanical parameters, the maximum shear stress of the soil is generated. and critical shear strength of soil failure ;

[0100] Preliminary output module for analyzing maximum shear stress in soil and critical shear strength of soil failure Size, output comprehensive toughness evaluation index ZPR or execute comprehensive analysis module and comprehensive output module according to the results;

[0101] Comprehensive analysis module, used to generate yield displacement and ultimate displacement through correlation analysis based on finite element coupling model, and then calculate ductility coefficient ; Perform correlation analysis on maximum vibration velocity and seismic wave time to generate energy dissipation Analyze the stiffness of the finite element coupling model after coupling simulated seismic waves, and further perform correlation analysis based on the stiffness to generate the damage index D;

[0102] The comprehensive output module is used to perform correlation analysis on the ductility coefficient, energy dissipation and damage index to generate a comprehensive toughness evaluation index ZPR; the comprehensive toughness evaluation index ZPR is compared with the threshold value to output the seismic resistance level of the wharf structure.

[0103] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0104] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on the specific application and design constraints of the technical solution.

[0105] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, and may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the objectives of this embodiment based on actual needs.

[0106] The above is only a specific implementation method of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the protection scope of the present application.

Claims

1. The finite element-based seismic toughness assessment method for high-piled piers is characterized by: The specific steps include: S1. Collect pile foundation structural and material parameters, build a three-dimensional structural model based on finite element software, and couple the elastic-plastic constitutive characteristics of the high-piled pier to generate a finite element pier model to simulate the mechanical behavior of the pier structure in the elastic and plastic stages; S2. Collect soil mechanical parameters and interface parameters, input the soil mechanical parameters and interface parameters into finite element software, generate a finite element soil model, couple the finite element soil model with the finite element wharf model, and generate a finite element coupling model for comprehensive simulation of the interaction between the wharf structure and the soil; S3. Generate simulated seismic waves based on historical earthquake data, apply the simulated seismic waves to the finite element coupling model, analyze the natural frequency of the high-pile pier and generate the maximum displacement and maximum vibration velocity of the high-pile pier; generate the maximum shear stress of the soil based on the simulated seismic waves and soil mechanical parameters and critical shear strength of soil failure ; S4, when the soil has the maximum shear stress Greater than the critical shear strength of soil failure When the output comprehensive toughness evaluation index ZPR is 0, the maximum shear stress of the soil is Less than the critical shear strength of soil failure When , execute steps S5 and S6; S5. Based on the finite element coupling model, the yield displacement and ultimate displacement are generated through correlation analysis, and then the ductility coefficient is calculated ; Perform correlation analysis on maximum vibration velocity and seismic wave time to generate energy dissipation Analyze the stiffness of the finite element coupling model after coupling simulated seismic waves, and further perform correlation analysis based on the stiffness to generate the damage index D; S6. Conduct correlation analysis on the ductility coefficient, energy dissipation, and damage index to generate a comprehensive toughness evaluation index ZPR; compare the comprehensive toughness evaluation index ZPR with the threshold value to output the seismic resistance grade of the wharf structure.

2. The finite element-based seismic toughness assessment method for high-piled piers according to claim 1 is characterized by: Pile foundation structural parameters include pile diameter, pile length, and pile cap size; pile foundation material parameters include the elastic modulus of the pier. , Poisson's ratio of the pier, yield strength of the pier , Pier yield strain ; The pile diameter d is the cross-sectional diameter of the pile of the high-pile pier, the pile length L is the depth of the pile, and the platform size includes length, width and height, which are used to construct the three-dimensional model of the high-pile pier. The elastic modulus of the pier is the elastic modulus of the high-pile pier, Poisson's ratio Used to reflect the lateral deformation characteristics of high-pile piers under axial stress, the pier yield strength The critical stress at which the three-dimensional model of the high-piled pier begins to produce plastic deformation, and the pier yield strain is the strain value of the pier yield strength, where .

3. The finite element-based seismic toughness assessment method for high-piled piers according to claim 2 is characterized by: Elastic modulus of the pier , Pier yield strength , Pier yield strain Correlation analysis is performed to construct the elastoplastic constitutive characteristics of the high-pile wharf based on the following formula: ； in, is the predicted stress of the high-piled pier, is the hardening modulus of the high-pile wharf, is the strain of the high-pile pier. The elastoplastic constitutive characteristics of the high-pile pier are used to reflect the relationship between the strain and stress of the high-pile pier.

4. The finite element-based seismic toughness assessment method for high-piled piers according to claim 3 is characterized by: Soil layer mechanical parameters include soil depth, soil density, internal friction angle, cohesion, soil elastic modulus, soil Poisson's ratio, and particle diameter; interface parameters include interface friction angle and bond strength; soil depth h is the depth of the piles of the high-pile wharf inserted into the soil, and particle diameter is the average diameter of the soil particles in the area where the high-pile pier is located, and the earthquake wave is simulated to interfere with the finite element coupling model. The duration of the earthquake wave is T, and the peak acceleration is A. The stiffness k of the finite element coupling model and the mass m of the high-pile pier are analyzed for correlation, and the natural frequency of the high-pile pier is generated. It is used to reflect the frequency of natural vibration of high-pile piers without external excitation, conduct correlation analysis on the natural frequency of high-pile piers, and generate the maximum displacement of high-pile piers. , and generate the maximum vibration speed of the high-pile pier , based on the formula: ; The correlation analysis between seismic waves and soil mechanical parameters is performed to generate the maximum shear stress of the soil and the critical shear strength of soil failure. The formula is: ; in, is the equivalent acceleration ratio caused by seismic waves under unit gravity, , is the maximum shear stress of the soil, which is used to reflect the maximum shear force of the soil under the influence of simulated seismic waves, h is the depth of the soil, is the soil density, is the critical shear strength of soil failure, which is used to reflect the ultimate shear stress value of soil resisting shear failure. is the soil cohesion, is the effective stress of soil, , g is the acceleration due to gravity, is the internal friction angle, when When the soil is severely damaged under the simulated earthquake wave condition, it cannot support the high-pile pier. At this time, the comprehensive toughness evaluation index ZPR is set to 0.

5. The finite element-based seismic toughness assessment method for high-piled piers according to claim 4 is characterized by: Apply a horizontal thrust F to the pile top of the finite element coupling model, so that the finite element coupling model is in the elastic stage and the soil does not undergo nonlinear damage, and obtain the displacement of the point where the horizontal thrust is applied , according to the formula , the stiffness k value of the finite element coupling model is obtained through fitting analysis.

6. The finite element-based seismic toughness assessment method for high-piled piers according to claim 5 is characterized by: Apply load to the finite element coupling model and increase the load gradually to obtain displacement data. The yield displacement and ultimate displacement are determined by the offset method. The displacement corresponding to the plastic deformation of the three-dimensional model part of the finite element coupling model begins, and the limit displacement The maximum load-bearing deformation of the three-dimensional model of the finite element coupling model is obtained by performing a correlation analysis on the yield displacement and the ultimate displacement to generate the ductility coefficient based on the following formula: ； Perform correlation analysis on maximum vibration velocity and seismic waves to generate energy dissipation , based on the formula: ； Among them, the ductility coefficient is used to reflect the deformation capacity and ductility of the structure under earthquake action, energy dissipation It is the energy that is no longer stored in a recoverable elastic form when the finite element coupling model converts the input mechanical energy into other forms of energy during the load deformation process. Energy dissipation is used to reflect the energy absorption and consumption capacity of the structure during an earthquake. is the structural stress of the wharf, ; The damage index D is generated by performing a correlation analysis on the stiffness k of the finite element coupling model, based on the following formula: ； The damage index D is used to reflect the damage degree of the high-pile pier after the earthquake wave. is the stiffness of the finite element coupling model after the seismic wave, based on the formula: ； in, is the reaction force variation of the pile support in the unloading section of the finite element coupling model, is the displacement change of the pile foundation support in the unloading section of the finite element coupling model.

7. The finite element-based seismic toughness assessment method for high-piled piers according to claim 6, characterized in that: Correlation analysis is performed on the ductility coefficient, energy dissipation, and damage index to generate the comprehensive toughness evaluation index ZPR. The formula is as follows: ； Comprehensive toughness evaluation index Used to reflect the seismic resistance of high-pile piers.

8. The finite element-based seismic toughness assessment method for high-piled piers according to claim 1 is characterized by: The seismic toughness evaluation index is used to reflect the overall seismic performance and toughness level of the structure. The seismic grade is used to reflect the safety performance level of the structure under earthquake action. With threshold Compare and output the seismic grade of the wharf structure. When the seismic resistance level of the output terminal structure is level 2, the seismic resistance of the terminal structure is poor, and manual repair and maintenance of the terminal is required; when When the seismic resistance level of the output terminal structure is level one, the seismic resistance of the terminal structure is good and needs to be continued to be monitored.

9. A finite element-based seismic toughness assessment system for a high-piled pier, used to implement the finite element-based seismic toughness assessment method for a high-piled pier according to claim 1, characterized in that: include: The wharf model construction module is used to collect pile foundation structural parameters and material parameters, build a three-dimensional structural model based on finite element software, and couple the elastic-plastic constitutive characteristics of the high-pile wharf to generate a finite element wharf model; Comprehensive model building module, used to collect soil mechanical parameters and interface parameters, input soil mechanical parameters and interface parameters based on finite element software, generate finite element soil model, couple the finite element soil model with the finite element wharf model to generate finite element coupling model; The seismic wave simulation module is used to generate simulated seismic waves based on historical seismic data, apply the simulated seismic waves to the finite element coupling model, analyze the natural frequency of the high-pile pier and generate the maximum displacement and maximum vibration velocity of the high-pile pier; based on the simulated seismic waves and soil mechanical parameters, the maximum shear stress of the soil is generated. and critical shear strength of soil failure ; Preliminary output module for analyzing maximum shear stress in soil and critical shear strength of soil failure Size, output comprehensive toughness evaluation index ZPR or execute comprehensive analysis module and comprehensive output module according to the results; Comprehensive analysis module, used to generate yield displacement and ultimate displacement through correlation analysis based on finite element coupling model, and then calculate ductility coefficient ; Correlation analysis of maximum vibration velocity and seismic wave time to generate energy dissipation Analyze the stiffness of the finite element coupling model after coupling simulated seismic waves, and further perform correlation analysis based on the stiffness to generate the damage index D; The comprehensive output module is used to perform correlation analysis on the ductility coefficient, energy dissipation and damage index to generate a comprehensive toughness evaluation index ZPR; the comprehensive toughness evaluation index ZPR is compared with the threshold value to output the seismic resistance level of the wharf structure.

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