A method for suppressing vibration of an ancient seawall based on pile driving control of a containment pile

Abstract

This invention discloses a method for suppressing vibration of ancient seawalls based on pile driving control. The method involves: constructing a pile driving control system based on an elasto-plastic t-z spring; inputting construction parameters based on on-site pile driving and geological survey data of the ancient seawall; outputting the soil resistance at different times from the pile side using the elasto-plastic t-z spring-based control system, and fitting the soil resistance function; constructing a site model of the ancient seawall based on geological survey data, and inputting the soil resistance function and vibration threshold; analyzing stress wave diffusion using the discontinuous Galerkin finite element method and determining whether the vibration of the ancient seawall meets the specifications, and then automatically adjusting accordingly. This invention enables real-time control of pile driving based on the vibration of the ancient seawall, timely suppression of seawall vibration, and prevention of damage to the ancient seawall, providing a reference for vibration control of ancient seawalls.

Description

Technical Field

[0001] This invention relates to a method for suppressing vibrations in ancient seawalls, specifically a method for suppressing vibrations in ancient seawalls based on pile driving control of retaining piles. Technical Background

[0002] The Qiantang River Haining Ming and Qing Dynasty Fish Scale Old Seawall (hereinafter referred to as the "Ancient Seawall") is a large-scale flood (tidal) control project protecting the northern Zhejiang and southern Jiangsu-Shanghai areas. It has been in operation for over 200 years, with some sections even exceeding 300 years. According to the "Qiantang River Survey Report" compiled in 1958, the Qiantang River Ancient Seawall exhibits signs of collapse and tilting. The "Qiantang River Seawall Survey Data" of 1980 shows that the lower half of the seawall's stone slabs are prone to loss, and some sections show subsidence. The 2012 "Research on the Protection of the Qiantang River Riverside Flood and Tidal Control Ancient Seawall" conducted a comprehensive survey and on-site investigation of the Qiantang River Riverside Ancient Seawall, revealing potential hazards such as outward tilting, subsidence, bulging, cracking, weathering, mortar joint detachment, stone slab loss, hollowing of the seawall foundation, and soil erosion on the back slope in some sections. As part of the Qiantang River Riverside Flood Control Seawall structure, its operational safety has always been a major concern.

[0003] As a water conservancy project with over a century of history, the vibration safety of the ancient seawall is particularly critical, and strict regulations exist in both domestic and international standards. The "Safety Regulations for Blasting" (GB6722-2014) stipulates that for general ancient buildings and historical sites, when the vibration frequency is less than or equal to 10Hz, the maximum particle vibration velocity shall not exceed 0.2cm / s; when the vibration frequency is between 10Hz and 50Hz, the maximum particle vibration velocity shall not exceed 0.3cm / s; and when the vibration frequency is greater than 50Hz, the maximum particle vibration velocity shall not exceed 0.5cm / s. The "Permissible Vibration Standard for Building Engineering" (GB50868-2013) stipulates that for vibration-sensitive buildings with protective value, when the vibration frequency is less than 10Hz, the maximum particle vibration velocity shall not exceed 0.15cm / s; when the vibration frequency is less than 50Hz, the maximum particle vibration velocity shall not exceed 0.3cm / s; and when the vibration frequency is less than 100Hz, the maximum particle vibration velocity shall not exceed 0.4cm / s. The German building vibration standard (DIN4150) stipulates that for vibration-sensitive and protected building facilities, the maximum particle vibration velocity shall not exceed 0.3 cm / s when the vibration frequency is less than 10 Hz; the maximum particle vibration velocity shall not exceed 0.8 cm / s when the vibration frequency is less than 50 Hz; and the maximum particle vibration velocity shall not exceed 1 cm / s when the vibration frequency is less than 100 Hz.

[0004] However, sporadic repairs and emergency repairs at the foot of the ancient seawall often require working during high tide. Conventional construction methods typically involve using excavators (or cranes) to drive sheet piles for the seawall's front retaining structure. If the vibrations generated during the pile driving process exceed a certain threshold, they can impact the ancient seawall, causing cracks, settlement, tilting, or even collapse. Therefore, timely control of the pile driving process to suppress the spread of stress waves and thus mitigate the impact of vibrations on the ancient seawall is necessary and crucial.

[0005] The essence of the vibration impact of pile driving in front of the ancient seawall is the diffusion of stress waves generated at the pile-soil interface during the pile driving process. These stress waves are mainly shear waves generated by the shear (Tz spring) at the pile-soil interface. Currently, most methods for analyzing the impact of construction vibration use finite element modeling. However, this method does not focus on the source of stress wave generation, resulting in poor accuracy. Furthermore, due to the complexity of pile-soil interaction, reproducing the pile driving process in a single finite element software is time-consuming, leading to lengthy calculation and analysis times. In situations such as flood control and emergency rescue of the ancient seawall, existing methods cannot provide timely control over pile driving in front of the seawall, thus failing to suppress the adverse effects of vibration on the ancient seawall. Summary of the Invention

[0006] This invention provides a vibration suppression method for ancient seawalls based on pile driving control, addressing the principles of vibration impact during the pile driving process and construction. This method establishes a pile driving control system based on an elasto-plastic Tz spring. By comprehensively considering the evolution of side resistance throughout the entire pile driving process, it can more realistically simulate the shearing action between the pile foundation sidewall and the soil during pile driving, using this as the source of stress waves generated during pile driving. The impact of pile driving vibration on the ancient seawall is analyzed, and the analysis results, after comparison with standard requirements, are fed back to the elasto-plastic Tz spring-based pile driving control system to adjust the hammer force, thereby controlling the pile driving vibration and suppressing its adverse effects on the ancient seawall.

[0007] To achieve the above-mentioned technical objectives, the technical solution of the present invention is: a method for suppressing vibration of ancient seawalls based on pile driving control of retaining piles, comprising the following steps:

[0008] Step 1: Construct a pile driving control system for retaining piles based on elasto-plastic Tz springs; the pile driving control system for retaining piles based on elasto-plastic Tz springs includes a parameter input module, a hammer force calculation module, a resistance calculation module, a motion control module, and a pile positioning module;

[0009] Step 2: Based on the on-site construction data of the retaining piles of the ancient seawall and the geological survey data of the ancient seawall site, input the construction parameters to be used in the parameter input module;

[0010] Step 3: The proposed construction parameters are transmitted by the parameter input module to the hammer impact force calculation module and the resistance calculation module, respectively. The hammer impact force calculation module is used to calculate the hammer impact force acting on the pile top; the resistance calculation module is used to calculate the soil resistance on the pile side using an elastic-plastic Tz spring, specifically by substituting the proposed construction parameters into the definition of the elastic-plastic Tz spring for calculation.

[0011] Step 4: The calculation results of the hammer impact force calculation module and the resistance calculation module, as well as the construction parameters to be used, are transmitted to the motion control module, which is used to calculate the displacement of the pile foundation.

[0012] Step 5: The displacement of the pile foundation is transmitted to the pile foundation positioning module, which is used to calculate the current position of the pile foundation. If the pile foundation has not reached the research depth, then repeat steps 2-4; otherwise, proceed to step 6.

[0013] Step 6: The pile driving control system based on the elastoplastic Tz spring outputs the pile side soil resistance at different times, and the pile side soil resistance at different times is fitted to obtain the pile side soil resistance function.

[0014] Step 7: Construct a site model of the ancient seawall based on geological survey data, and reserve the pile foundation outline for the research depth at the pile driving location;

[0015] Step 8: Based on the soil resistance function of the pile side and the pile foundation profile, stress wave diffusion analysis is performed using the discontinuous Galerkin finite element method to obtain the vibration velocity of the ancient seawall at different times.

[0016] Step 9: Set the vibration threshold of the ancient seawall and determine whether the vibration of the ancient seawall meets the requirements. If it does, output the hammering force. If it does not meet the requirements, feed the hammering force back to the pile driving control system based on the elastic-plastic Tz spring, adjust the construction parameters to be used, and repeat steps 6-8.

[0017] Furthermore, in step 1, the retaining pile driving control system based on elastoplastic Tz springs is a multi-module interactive analysis system, with each module providing an interface to call the corresponding software for calculation.

[0018] Furthermore, in step 1, within each time step, the retaining pile driving control system based on the elasto-plastic Tz spring implements the following: within each time step, the parameter input module, the hammer force calculation module, and the resistance calculation module input the proposed construction parameters, hammer force, and pile side resistance values ​​to the motion control module; the motion control module calculates the pile foundation movement process and inputs the displacement increment and velocity increment for that time period to the pile foundation positioning module.

[0019] Furthermore, in step 1, the elastoplastic tz spring is an expression of the interaction between the pile and the soil, where t is the shear force at the pile-soil interface and z is the relative displacement between the pile side and the soil side.

[0020] Furthermore, in step 1, the elastoplastic Tz spring is obtained by modifying an existing Tz spring model; in the process of describing the loading-unloading path, the elastoplastic Tz spring defines an elastic stiffness K for the displacement increment dz. e and plastic stiffness K p The elastic part dz is clarified e and the plastic increment part dz p The definition of an elastoplastic Tz spring is:

[0021]

[0022]

[0023] In the formula, t u For the pile-soil interface strength, t m is the maximum interfacial frictional resistance during loading, and h is the shape parameter of the tz curve.

[0024] Furthermore, the calculations of the motion control module and the pile positioning module are completed in the corresponding software based on the pile design dimensions, pile material, and boundary condition information. The pile body is constructed using Euler-Bernoulli beam elements.

[0025] Furthermore, in step 2, the proposed construction parameters include pile length L, outer diameter D, wall thickness t0, and hammer core mass m. a Hammer cap mass m r , elastic coefficient k of the cushion layer c Pile damping Z, interface friction angle δ f , pile body and pile side elastic limit value Q s and Q b The end resistance coefficients β and N of non-cohesive soils t Undrained strength of cohesive soil (s) u Damping input parameter J s and J b Effective severity γ, research depth H.

[0026] Furthermore, in step 6, the pile side soil resistance at different times is a list of values ​​output by the resistance calculation module, which is then fitted into a pile side soil resistance function using Python.

[0027] Furthermore, in step 7, the ancient seawall site model based on geological survey data is specifically a site model constructed according to the topography of the pile driving construction site, which includes the ancient seawall and its surrounding geological structures. The pile outline is reserved at the pile driving location, and the pile side soil resistance function is set at the pile outline.

[0028] Further, in step 8, the vibration threshold of the ancient seawall is a safe permissible vibration value based on the "Safety Regulations for Blasting" (GB6722-2014), "Permissible Vibration Standard for Building Engineering" (GB50868-2013), the US building visible appearance damage threshold standard (USBMRI-8507), the German building vibration standard (DIN4150), or the British appearance damage vibration reference standard (British Standard 7385, BS6472).

[0029] Furthermore, in step 8, the stress wave diffusion analysis based on the discontinuous Galerkin finite element method has good mathematical properties such as conservation and convergence, can easily handle complex boundary and boundary value problems, can easily improve accuracy, can capture discontinuity information well, and can accurately simulate the existence of shock waves. In terms of algorithm, it is equivalent to decoupling the large-scale matrix of the finite element method, thus avoiding the situation in the finite element method that requires global solution of a large-scale linear equation system.

[0030] Furthermore, in step 8, the governing equation for stress wave diffusion analysis based on the discontinuous Galerkin finite element method is the velocity-stress elastic wave equation:

[0031]

[0032] Where ρ is the density of the object, and σ is the stress tensor. Here, f represents the external force source term, C is the stiffness matrix, v is the vibration velocity, and t is time.

[0033] Furthermore, in step 8, the stress wave diffusion analysis based on the discontinuous Galerkin finite element method can obtain the time history change of vibration velocity at any point in the soil. By analyzing the vibration velocity of the soil near the ancient seawall, it can be determined whether it meets the specification requirements, and then corresponding adjustments can be made.

[0034] Furthermore, in step 9, the adjustment of the hammering force is to reduce the hammering force to 2%-5% of the original force. The specific value is determined by the difference between the vibration speed of the pond body and the allowable value in the specification. The larger the difference, the larger the corresponding adjustment amplitude.

[0035] Furthermore, in step 9, the output hammering force and average vibration velocity of the pond body are obtained through mutual feedback and continuous iteration of the pile driving process (steps 1-5) and the ancient seawall vibration analysis process (steps 6-9) of the elastoplastic Tz spring retaining pile driving control system. At this time, the average vibration velocity of the pond body meets the input vibration threshold.

[0036] Compared with the prior art, the present invention provides a method for suppressing vibration of ancient seawalls based on pile driving control of retaining piles, which has the following beneficial effects:

[0037] (1) The evolution law of side resistance in the whole process of pile driving is comprehensively considered by using elastoplastic Tz springs, which more realistically represents the "source" of pile driving vibration, that is, the mutual shearing action between the pile foundation sidewall and the soil, and provides a basis for subsequent stress wave propagation analysis and ancient seawall vibration control.

[0038] (2) In the process of dynamic calculation, the traditional finite element method is not accurate enough in terms of time processing. It relies on the global formation and solution of a large-scale linear algebraic equation system, which makes its storage and computational load large and it is not easy to improve the numerical accuracy. The discontinuous Galerkin finite element method (DG-FEM) is used to deal with the stress wave diffusion problem. It has good mathematical properties such as conservation and convergence, and it is easy to handle complex boundary and boundary value problems. It is easy to improve the accuracy, can capture discontinuity information well, and can accurately simulate the existence of shock waves. In terms of algorithm, it is equivalent to decoupling the large-scale matrix of the finite element, thus avoiding the situation in the finite element method that requires global solution of a large-scale linear equation system.

[0039] (3) The separate modeling of the piling process and stress wave propagation saves calculation time and improves calculation efficiency. It can realize real-time control of piling operations around the ancient seawall, which is suitable for handling and using practical engineering problems and provides an important reference for vibration control of the ancient seawall. Attached Figure Description

[0040] Figure 1 This is a flowchart of the present invention;

[0041] Figure 2 This is a Python-based curve fitting diagram of pile side soil resistance.

[0042] Figure 3 This is a schematic diagram of an ancient seawall site model based on geological survey data;

[0043] Figure 4 This is a diagram showing the diffusion of stress waves during pile driving. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0045] Example

[0046] A method for vibration suppression of ancient seawalls based on pile driving control, such as Figure 1 As shown, it includes the following steps:

[0047] Step 1: Construct a pile driving control system for retaining piles based on elasto-plastic Tz springs; the pile driving control system for retaining piles based on elasto-plastic Tz springs includes a parameter input module, a hammer force calculation module, a resistance calculation module, a motion control module, and a pile positioning module;

[0048] Step 2: Based on the on-site construction data of the retaining piles of the ancient seawall and the geological survey data of the ancient seawall site, input the construction parameters to be used in the parameter input module;

[0049] Step 3: The proposed construction parameters are transmitted by the parameter input module to the hammer impact force calculation module and the resistance calculation module, respectively. The hammer impact force calculation module is used to calculate the hammer impact force acting on the pile top; the resistance calculation module is used to calculate the soil resistance on the pile side using an elastic-plastic Tz spring, specifically by substituting the proposed construction parameters into the definition of the elastic-plastic Tz spring for calculation.

[0050] Step 4: The calculation results of the hammer impact force calculation module and the resistance calculation module, as well as the construction parameters to be used, are transmitted to the motion control module, which is used to calculate the displacement of the pile foundation.

[0051] Step 5: The displacement of the pile foundation is transmitted to the pile foundation positioning module, which is used to calculate the current position of the pile foundation. If the pile foundation has not reached the research depth, then repeat steps 2-4; otherwise, proceed to step 6.

[0052] Step 6: The pile driving control system based on the elastoplastic Tz spring outputs the pile side soil resistance at different times, and the pile side soil resistance at different times is fitted to obtain the pile side soil resistance function.

[0053] Step 7: Construct a site model of the ancient seawall based on geological survey data, and reserve the pile foundation outline for the research depth at the pile driving location;

[0054] Step 8: Based on the soil resistance function of the pile side and the pile foundation profile, stress wave diffusion analysis is performed using the discontinuous Galerkin finite element method to obtain the vibration velocity of the ancient seawall at different times.

[0055] Step 9: Set the vibration threshold of the ancient seawall and determine whether the vibration of the ancient seawall meets the requirements. If it does, output the hammering force. If it does not meet the requirements, feed the hammering force back to the pile driving control system based on the elastic-plastic Tz spring, adjust the construction parameters to be used, and repeat steps 6-8.

[0056] In step 1, the retaining pile driving control system based on elastoplastic Tz springs is a multi-module interactive analysis system, with each module providing an interface to call the corresponding software for calculation. In this embodiment, the hammer impact force calculation module and the resistance calculation module call MATLAB software for calculation, while the motion control module and the pile positioning module call COMSOL Multiphysics software for calculation.

[0057] In step 1, within each time step, the retaining pile driving control system based on the elasto-plastic Tz spring implements the following: within each time step, the parameter input module, the hammer force calculation module, and the resistance calculation module input the proposed construction parameters, hammer force, and pile side resistance values ​​to the motion control module; the motion control module calculates the pile foundation movement process and inputs the displacement increment and velocity increment for that time period to the pile foundation positioning module.

[0058] In step 1, the elastoplastic Tz spring is obtained by modifying an existing Tz spring model. The elastoplastic Tz spring is an expression of the interaction between the pile and the soil, where t is the shear force at the pile-soil interface and z is the relative displacement between the pile side and the soil side. In the description of the loading-unloading path, the elastoplastic Tz spring defines an elastic stiffness K for the displacement increment dz. e and plastic stiffness K p The elastic part dz is clarified e and the plastic increment part dz p The definition of an elastoplastic Tz spring is:

[0059]

[0060]

[0061] Among them, t u For the pile-soil interface strength, t m h represents the maximum interfacial frictional resistance during the loading history process, and h is the shape parameter of the tz curve.

[0062] In step 1, the pile-soil interface strength t of the elastoplastic tz spring u The shape parameter h of the tz curve is obtained by the UWA-05 method and is obtained by the ring shear test.

[0063] In step 1, the calculations of the motion control module and the pile positioning module are completed in the corresponding software COMSOL Multiphysics based on the pile design dimensions, pile material, and boundary condition information. The pile body is constructed using Euler-Bernoulli beam elements.

[0064] In step 2, the proposed construction parameters include pile length L, outer diameter D, wall thickness t0, and hammer core mass m. a Hammer cap mass m r , elastic coefficient k of the cushion layer c Pile damping Z, interface friction angle δ f , pile body and pile side elastic limit value Q s and Q b The end resistance coefficients β and N of non-cohesive soils t Undrained strength of cohesive soil (s) u Damping input parameter J s and J b Effective severity γ, research depth H.

[0065] In step 6, the pile side soil resistance at different times is a list of values ​​output by the resistance calculation module. These values ​​are then fitted into a pile side soil resistance function using Python, as shown below. Figure 2 As shown.

[0066] In step 7, the ancient seawall site model based on geological survey data is specifically a site model constructed according to the topography of the piling construction site, including the ancient seawall and its surrounding geological structures, such as... Figure 3 As shown, a pile outline is reserved at the pile driving location, and the pile side soil resistance function is set at the pile outline.

[0067] In step 8, the vibration threshold of the ancient seawall is a safe permissible vibration value based on the "Safety Code for Blasting" (GB6722-2014), "Permissible Vibration Standard for Building Engineering" (GB50868-2013), the US building visible appearance damage threshold standard (USBMRI-8507), the German building vibration standard (DIN4150), or the British appearance damage vibration reference standard (British Standard 7385, BS6472).

[0068] In step 8, the stress wave diffusion analysis based on the discontinuous Galerkin finite element method has good mathematical properties such as conservation and convergence, can easily handle complex boundary and boundary value problems, can easily improve accuracy, can capture discontinuity information well, and can accurately simulate the existence of shock waves. Algorithmically, it is equivalent to decoupling the large-scale matrix of the finite element method, thus avoiding the situation in the finite element method that requires global solution of large-scale linear equations.

[0069] In step 8, the governing equation for stress wave diffusion analysis based on the discontinuous Galerkin finite element method is the velocity-stress elastic wave equation:

[0070]

[0071] Where ρ is the density of the object, and σ is the stress tensor. Here, f represents the external force source term, C is the stiffness matrix, v is the vibration velocity, and t is time.

[0072] In step 8, the stress wave diffusion analysis based on the discontinuous Galerkin finite element method can obtain the time history variation of vibration velocity at any point in the soil, specifically as follows: Figure 4 By analyzing the vibration velocity of the soil near the ancient seawall, it can be determined whether it meets the specifications, and then corresponding adjustments can be made.

[0073] In step 9, the hammering force is adjusted to reduce the hammering force to 2%-5% of the original force. The specific value is determined by the difference between the vibration velocity of the pond body and the allowable value in the specification. The larger the difference, the larger the corresponding adjustment amplitude.

[0074] In step 9, the output hammer force and average vibration velocity of the pond body are obtained by mutual feedback and continuous iteration of the pile driving process (steps 1-5) and the ancient seawall vibration analysis process (steps 6-9) of the elastoplastic Tz spring retaining pile driving control system. At this time, the average vibration velocity of the pond body meets the input vibration threshold.

[0075] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for suppressing vibration of ancient seawalls based on pile driving control of retaining piles, characterized in that, The steps include the following: Step 1: Construct a pile driving control system for retaining piles based on elasto-plastic Tz springs; the pile driving control system for retaining piles based on elasto-plastic Tz springs includes a parameter input module, a hammer force calculation module, a resistance calculation module, a motion control module, and a pile positioning module; Step 2: Based on the on-site construction data of the retaining piles of the ancient seawall and the geological survey data of the ancient seawall site, input the construction parameters to be used in the parameter input module; Step 3: The proposed construction parameters are transmitted by the parameter input module to the hammer force calculation module and the resistance calculation module, respectively. The hammer force calculation module is used to calculate the hammer force acting on the pile top. The resistance calculation module is used to calculate the soil resistance along the pile using an elastic-plastic Tz spring. Step 4: The calculation results of the hammer impact force calculation module and the resistance calculation module, as well as the construction parameters to be used, are transmitted to the motion control module, which is used to calculate the displacement of the pile foundation. Step 5: The displacement of the pile foundation is transmitted to the pile foundation positioning module, which is used to calculate the current position of the pile foundation. If the pile foundation has not reached the research depth, then steps 2-4 are repeated. Otherwise proceed to step 6; Step 6: The pile driving control system based on the elastoplastic Tz spring outputs the pile side soil resistance at different times, and the pile side soil resistance at different times is fitted to obtain the pile side soil resistance function. Step 7: Construct a site model of the ancient seawall based on geological survey data, and reserve the pile foundation outline for the research depth at the pile driving location; Step 8: Based on the soil resistance function of the pile side and the pile foundation profile, stress wave diffusion analysis is performed using the discontinuous Galerkin finite element method to obtain the vibration velocity of the ancient seawall at different times. Step 9: Set the vibration threshold of the ancient seawall and determine whether the vibration of the ancient seawall meets the requirements. If it does, output the hammering force and the average vibration velocity of the seawall. If it does not meet the requirements, feed the hammering force back to the pile driving control system based on the elastic-plastic Tz spring, adjust the construction parameters to be used, and repeat steps 6-8.

2. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 1, the retaining pile driving control system based on elastoplastic Tz spring is a multi-module interactive analysis system, and each module provides an interface to call the corresponding software for calculation. Within each time step, the retaining pile driving control system based on elastoplastic Tz springs implements the following: the parameter input module, the hammer force calculation module, and the resistance calculation module input the proposed construction parameters, hammer force, and pile side resistance values ​​to the motion control module; the motion control module calculates the pile foundation movement process and inputs the displacement increment and velocity increment for that time period to the pile foundation positioning module. The elastoplastic tz spring is an expression of the interaction between the pile and the soil, where t is the shear force at the pile-soil interface and z is the relative displacement between the pile side and the soil side.

3. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 2, characterized in that: In step 1, the elastoplastic Tz spring is obtained by modifying an existing Tz spring model; in the description of the loading-unloading path, the elastoplastic Tz spring defines an elastic stiffness K for the displacement increment dz. e and plastic stiffness K p The elastic part dz is clarified e and the plastic increment part dz p The definition of an elastoplastic Tz spring is: In the formula, t u For the pile-soil interface strength, t m is the maximum interfacial frictional resistance during loading, and h is the shape parameter of the tz curve.

4. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 2, characterized in that: The calculations for the motion control module and the pile positioning module are completed in the corresponding software based on the pile design dimensions, pile material, and boundary condition information. The pile body is constructed using Euler-Bernoulli beam elements.

5. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 2, the proposed construction parameters include pile length L, outer diameter D, wall thickness t0, and hammer core mass m. a Hammer cap mass m r , elastic coefficient k of the cushion layer c Pile damping Z, interface friction angle δ f , pile body and pile side elastic limit value Q s and Q b The end resistance coefficients β and N of non-cohesive soils t Undrained strength of cohesive soil (s) u Damping input parameter J s and J b Effective severity γ, research depth H.

6. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 6, the pile side soil resistance at different times is a list of values ​​output by the resistance calculation module, which is then fitted into a pile side soil resistance function using Python.

7. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 7, the ancient seawall site model based on geological survey data is specifically a site model constructed according to the topography of the pile driving construction site, which includes the ancient seawall and its surrounding geological structures. The pile outline is reserved at the pile driving location, and the pile side soil resistance function is set at the pile outline.

8. The method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 8, the vibration threshold of the ancient seawall is a safe permissible vibration value based on the "Safety Code for Blasting" (GB6722-2014), "Permissible Vibration Standard for Building Engineering" (GB50868-2013), the US building visible appearance damage threshold standard (USBMRI-8507), the German building vibration standard (DIN4150), or the British appearance damage vibration reference standard (British Standard 7385, BS6472).

9. A method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 8, the governing equation for stress wave diffusion analysis based on the discontinuous Galerkin finite element method is the velocity-stress elastic wave equation: Where ρ is the density of the object, and σ is the stress tensor. Here, f represents the external force source term, C is the stiffness matrix, v is the vibration velocity, and t is time.

10. A method for suppressing vibration of ancient seawalls based on pile driving control according to claim 1, characterized in that: In step 9, the method for adjusting the hammering force is to reduce the hammering force to 2%-5% of the original force.

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