A method, medium and system for evaluating the impact of pile sinking soil squeezing effect on pile foundation load

Abstract

The present invention provides a method, medium and system for evaluating the influence of soil squeezing effect of pile sinking on pile foundation load, which belongs to the technical field of soil squeezing effect of pile sinking, and includes: installing multiple vibration sensors and strain sensors at different depths and distances around the pile foundation, continuously collecting vibration signals and strain signals, and forming a vibration-strain signal group. After preprocessing and alignment, the optimal time window length is determined by time-frequency analysis method, and the time-frequency characteristics of each signal are extracted. Based on the established dynamic equation group, multiple analytical solutions describing the vibration propagation, stress distribution, deformation characteristics and pile-soil interaction of the soil around the pile foundation are solved. These analytical solutions and the characteristic group to be measured are used as input parameters to establish a mathematical model of soil squeezing effect of pile sinking, calculate the stress-strain state of the soil around the pile, and then evaluate the influence of soil squeezing effect on the bearing capacity of the pile foundation. Finally, according to the evaluation results, the bearing capacity change index of the pile foundation is calculated to determine the influence of soil squeezing effect on the pile foundation load.

Description

Technical Field

[0001] The present invention belongs to the technical field of soil squeezing effect of pile driving, and in particular, relates to a method, a medium and a system for evaluating the influence of soil squeezing effect of pile driving on pile foundation load. Background Art

[0002] Pile foundation is one of the widely used foundation forms in buildings and other civil engineering projects. Its bearing capacity is directly related to the safety and economy of the project. In the actual pile foundation construction process, the settlement of the pile foundation and the extrusion deformation of the surrounding soil will affect each other. This interaction is called "pile sinking and soil squeezing effect". The pile sinking and soil squeezing effect usually causes a certain degree of change in the stress state and deformation characteristics of the soil around the pile foundation, thereby affecting the bearing capacity of the pile foundation. Specifically, the soil squeezing effect will cause the non-uniformity of the stress-strain distribution of the soil around the pile, causing the side friction and end resistance of the pile foundation to change. If the soil squeezing effect is too large, it may cause a significant reduction in the bearing capacity of the pile foundation, seriously affecting the safe operation of the project. Therefore, accurately evaluating the impact of the pile sinking and soil squeezing effect on the bearing capacity is crucial to ensure the safety and economy of the pile foundation design. At present, the industry has widely adopted a method combining field monitoring and theoretical analysis to study the pile sinking and soil squeezing effect. Field monitoring mainly includes the use of sensors such as strain gauges and displacement gauges to continuously record the strain and displacement changes of the surrounding soil during the pile foundation construction process. The theoretical analysis is mainly based on the soil constitutive relationship and pile-soil interaction theory, and the corresponding mechanical model is established to simulate and predict the soil squeezing effect of pile sinking.

[0003] However, the monitoring data of existing technologies and theoretical analysis results are often difficult to effectively integrate, resulting in weak reliability and pertinence of the evaluation results, making it difficult to provide sufficient basis for engineering design. Summary of the invention

[0004] In view of this, the present invention provides a method, medium and system for evaluating the influence of pile driving soil squeezing effect on pile foundation load, which can solve the technical problem that monitoring data and theoretical analysis results in the prior art are often difficult to effectively integrate, resulting in weak reliability and pertinence of evaluation results, and it is difficult to provide sufficient basis for engineering design.

[0005] The present invention is achieved in that:

[0006] A first aspect of the present invention provides a method for evaluating the influence of soil squeezing effect of pile sinking on pile foundation load, which comprises the following steps:

[0007] S10, installing a plurality of vibration sensors and strain sensors at different depths and distances around the pile foundation, and continuously collecting vibration signals and strain signals during the downward construction of the pile foundation to form a vibration-strain signal group;

[0008] S20, preprocessing the collected vibration-strain signal, including denoising, filtering and signal alignment, to improve data quality;

[0009] S30, according to each signal in the aligned vibration-strain signal group, using a time-frequency analysis method to determine an optimal time window length to capture the characteristics of soil vibration and deformation around the pile foundation;

[0010] S40, using the determined optimal time window length, extracting the time-frequency characteristics of each signal, including amplitude, frequency, phase and strain magnitude, and recording the time-frequency characteristics of all signals as a feature group to be measured;

[0011] S50, establishing a group of dynamic equations, including soil dynamic equations, soil stress-strain relationship equations, soil vibration propagation equations, soil deformation coordination equations, and pile-soil interaction equations;

[0012] S60, solving the group of dynamic equations to obtain multiple analytical solutions, which are a first analytical solution for describing the vibration propagation characteristics of the soil around the pile foundation, a second analytical solution for describing the stress distribution characteristics of the soil around the pile foundation, a third analytical solution for describing the deformation characteristics of the soil around the pile foundation, a fourth analytical solution for describing the pile-soil interaction characteristics, and a fifth analytical solution for describing the bearing capacity characteristics of the pile foundation;

[0013] S70, establishing a mathematical model of soil squeezing effect of pile sinking according to the multiple analytical solutions and the initial conditions and boundary conditions of the dynamic equations, and solving the stress-strain state of the soil around the pile with the characteristic group to be measured as input parameters;

[0014] S80, based on the solved stress-strain state of the soil around the pile, calculate the changes of the side friction and end resistance of the pile foundation, and then evaluate the influence of the soil squeezing effect on the bearing capacity of the pile foundation as the evaluation result;

[0015] S90. Based on the evaluation results, calculate the overall bearing capacity variation index of the pile foundation, determine the influence of the soil squeezing effect on the pile foundation load, and mark the potential bearing capacity reduction area.

[0016] Wherein, the step S10 specifically includes: installing multiple vibration sensors and strain sensors at different depths and distances around the pile foundation. These sensors are used to continuously collect vibration signals and strain signals during the pile foundation construction process. The vibration sensor is mainly used to capture the vibration characteristics of the surrounding soil, while the strain sensor is used to monitor the strain changes of the soil. These sensors should be arranged at different positions and depths around the pile foundation to fully obtain the spatiotemporal distribution characteristics of soil vibration and deformation. By reasonably arranging the sensor array, the complete information of the dynamic response of the soil during the pile foundation construction process can be effectively recorded, providing basic data for subsequent analysis and evaluation.

[0017] Wherein, the step S20 specifically includes: preprocessing the collected vibration-strain signal, including denoising, filtering and signal alignment. First, the original signal needs to be denoised to eliminate the influence of external interference noise on the signal. Common denoising methods include wavelet denoising, adaptive filtering, etc. Secondly, the signal is filtered, and a bandpass filter can be used to retain the frequency band related to soil vibration and deformation, and remove irrelevant high and low frequency components. Finally, the signals collected by different sensors need to be time-aligned to eliminate the time misalignment caused by propagation delay or acquisition time difference. These preprocessing measures can effectively improve the quality and reliability of the signal and lay the foundation for subsequent time-frequency analysis.

[0018] Wherein, the step S30 specifically includes: according to the aligned vibration-strain signal group, using the time-frequency analysis method to determine the optimal time window length. Time-frequency analysis is a very effective signal analysis tool that can simultaneously reflect the characteristics of the signal in the time domain and the frequency domain. In the present invention, the purpose of time-frequency analysis is to capture the time-varying characteristics of soil vibration and deformation around the pile foundation. By performing a short-time Fourier transform or a wavelet transform on each sensor signal, a time-frequency characteristic spectrum of the signal can be obtained. Then, combined with the physical process of soil vibration and deformation, the optimal time window length that can fully reflect the soil response characteristics is determined. This time window length determines the time resolution of the subsequent time-frequency feature extraction, which is crucial for accurately describing the dynamic response of the soil.

[0019] Wherein, the step S40 specifically includes: using the optimal time window length determined in step S30, extracting the time-frequency characteristics of each signal, including amplitude, frequency, phase and strain size. Specifically, performing a short-time Fourier transform on each sensor signal to obtain its time-frequency characteristic spectrum. Extracting characteristic parameters such as amplitude, frequency and phase from the spectrum to describe the vibration state of the soil at different time-frequency points. At the same time, using the strain signal measured by the sensor, the deformation characteristics of the soil can be directly obtained. The time-frequency characteristic parameters of all sensor signals are sorted into a characteristic parameter group as input data for subsequent analysis. These time-frequency characteristic parameters can comprehensively characterize the dynamic response process of the soil around the pile foundation and are the basis for establishing a soil-pile interaction model.

[0020] Wherein, the step S50 specifically includes: establishing a set of equations describing the dynamic behavior of pile foundation-soil, including soil dynamic equations, soil stress-strain relationship equations, soil vibration propagation equations, soil deformation coordination equations, and pile-soil interaction equations, etc. These equations together constitute a complete set of equations describing the dynamic behavior of pile foundation-soil, laying a foundation for subsequent analysis and solution.

[0021] Wherein, the step S60 specifically includes: solving the equation group established in step S50 to obtain multiple analytical solutions, which respectively describe the vibration propagation characteristics, stress distribution characteristics, deformation characteristics, pile-soil interaction characteristics and pile foundation bearing capacity characteristics of the soil around the pile foundation. These analytical solutions fully reflect the characteristics of various aspects of the pile foundation-soil dynamic system and provide a basis for the subsequent establishment of mathematical models.

[0022] Wherein, the step S70 specifically includes: according to the multiple analytical solutions obtained in step S60, as well as the initial conditions and boundary conditions of the equation group, a mathematical model of the soil squeezing effect of pile sinking is established. The characteristic group to be measured obtained in step S40 is substituted into the above analytical solution as an input parameter, and the stress-strain state of the soil around the pile is solved by numerical calculation. The core of this mathematical model is to utilize the time-frequency characteristics of the vibration-strain signal, and to simulate and predict the stress-strain response characteristics of the surrounding soil during the pile foundation construction process by solving the dynamic equation group.

[0023] Wherein, the step S80 specifically includes: based on the stress-strain state of the soil around the pile obtained in step S70, calculating the changes in the lateral friction and end resistance of the pile foundation. First, the shear strength parameters of the soil around the pile foundation are calculated using the soil strain state, and then the lateral friction is calculated according to the classical formula. Secondly, the bearing area and stress distribution at the end of the pile foundation are calculated using the soil stress state, and then the end resistance is calculated. Finally, the changes in the calculated lateral friction and end resistance are used as evaluation results to reflect the influence of the pile sinking and soil squeezing effect on the total bearing capacity of the pile foundation.

[0024] Wherein, the step S90 specifically includes: calculating the overall bearing capacity change index of the pile foundation according to the pile foundation bearing capacity change evaluation result obtained in step S80. The index reflects the influence of the soil squeezing effect on the pile foundation bearing capacity. By analyzing the value of the index, the influence of the soil squeezing effect on the pile foundation load can be determined. At the same time, it is also necessary to mark the potential bearing capacity reduction area according to the stress-strain distribution of the soil around the pile obtained in step S70. This information helps to take targeted reinforcement measures to ensure that the pile foundation can still meet the design requirements under the soil squeezing effect.

[0025] The soil dynamics equation is specifically:

[0026] The soil dynamics equation is specifically:

[0027]

[0028] Where ρ is the soil density, in kg / m 3 ; u is the soil displacement vector, unit is m; t is the time, unit is s; is the divergence operator; σ is the stress tensor, the unit is Pa; B is the unit mass body force vector, the unit is N / kg.

[0029] The soil stress-strain relationship equation is specifically:

[0030] σ=D·∈;

[0031] Where σ is the stress tensor, in Pa; d is the stiffness matrix, in Pa; ∈ is the strain tensor, dimensionless.

[0032] The soil vibration propagation equation is specifically:

[0033]

[0034] Where, u is the soil displacement vector, unit is m; t is the time, unit is s; c is the wave propagation velocity, unit is m / s; is the Laplace operator.

[0035] The soil deformation coordination equation is specifically:

[0036]

[0037] The pile-soil interaction equation is specifically:

[0038] p=C1·E s ·u+C2·σ′ v ·tanφ·u;

[0039] Where p is the pile-soil interface interaction force, in N / m 2 ; u is the soil displacement vector, unit is m; C1 and C2 are empirical coefficients, E s is the elastic modulus of soil, σ′ v is the effective vertical stress and φ is the internal friction angle.

[0040] Among them, the multiple analytical solutions are:

[0041] The first analytical solution describes the vibration propagation characteristics of the soil around the pile foundation, that is, the propagation law of the vibration signal in the soil in time and space, which is specifically expressed as:

[0042] u(x,T)=A cos(ωt-kx);

[0043] In the formula, A is the amplitude, ω is the angular frequency, and k is the wave number;

[0044] The second analytical solution describes the stress distribution characteristics of the soil around the pile foundation, that is, the stress state of the soil during the pile foundation construction process, which is specifically expressed as:

[0045] σ(x,t)=B exp(-αxc)sin(ωt-kx+φ);

[0046] In the formula, B is the stress amplitude, α is the attenuation coefficient, and φ is the phase;

[0047] The third analytical solution describes the deformation characteristics of the soil around the pile foundation, that is, the displacement and strain state of the soil during the pile foundation construction process, which is specifically expressed as:

[0048] ∈(x,t)=C exp(-βx)cos(ωt-KX+θ);

[0049] In the formula, C is the strain amplitude, β is the attenuation coefficient, and θ is the phase;

[0050] The fourth analytical solution describes the characteristics of pile-soil interaction, that is, the interaction force between the pile foundation and the surrounding soil, which is specifically expressed as:

[0051] p(x,t)=Dexp(-γx)sin(ωt-kx+ψ);

[0052] Where D is the amplitude of the interaction force, γ is the attenuation coefficient, and ψ is the phase;

[0053] The fifth analytical solution describes the characteristics of pile foundation bearing capacity, that is, the change of pile foundation bearing capacity under the soil squeezing effect, which is specifically expressed as:

[0054]

[0055] In the formula, is the bearing capacity of the pile foundation before construction, Δ Q (t) is the time-varying rate of change of bearing capacity.

[0056] The overall bearing capacity variation index of the pile foundation is specifically:

[0057]

[0058] In the formula, and are the total bearing capacity of the pile foundation before and after construction, respectively.

[0059] Optionally, the sensor installation positions in step S10 include being arranged at different depths such as the top, middle and bottom of the pile foundation, and at different radial distances around the pile foundation. In this way, the vibration and deformation response information of the soil at different positions and depths can be fully obtained.

[0060] Optionally, the preprocessing in step S20 also includes normalizing the signal to eliminate dimensional effects caused by sensor installation position, parameter differences, etc.

[0061] Optionally, the time-frequency analysis method in step S30 may also use other time-frequency analysis techniques such as wavelet packet analysis. These methods can effectively extract time-frequency features and lay the foundation for subsequent modeling analysis.

[0062] Optionally, the time-frequency characteristics in step S40 also include parameters such as power spectrum density and coherence function. These parameters can further reflect the energy characteristics and correlation of soil vibration and deformation.

[0063] Optionally, the mathematical model in step S70 may also be solved using numerical simulation methods such as finite element or boundary element to improve the accuracy and stability of the calculation.

[0064] Optionally, when calculating the lateral friction in step S80, it is also necessary to consider the variation of soil strength with depth and establish a reasonable strength distribution model.

[0065] A second aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores program instructions, and when the program instructions are executed, they are used to execute the above-mentioned method for evaluating the influence of pile driving and soil squeezing effect on pile foundation load.

[0066] A third aspect of the present invention provides a system for evaluating the impact of soil squeezing effect of pile driving on pile foundation load, which includes the above-mentioned computer-readable storage medium.

[0067] Compared with the prior art, the method, medium and system for evaluating the impact of pile sinking soil squeezing effect on pile foundation load provided by the present invention have the following beneficial effects:

[0068] 1. Make full use of on-site monitoring data: This method deploys multiple vibration sensors and strain sensors around the pile foundation, which can continuously collect the vibration and deformation response information of the soil in time and space, providing comprehensive basic data for subsequent analysis. Compared with the existing method that only relies on single-point monitoring, this method can more accurately capture the dynamic response characteristics of the soil around the pile foundation.

[0069] 2. Use advanced time-frequency analysis technology: This method uses time-frequency analysis methods, such as short-time Fourier transform and wavelet transform, to extract the time-frequency characteristic parameters of vibration-strain signals, such as amplitude, frequency and phase. These time-frequency characteristics can more comprehensively describe the vibration and deformation process of the soil, laying a good foundation for subsequent modeling and analysis.

[0070] 3. Establish a comprehensive dynamic analysis model: Based on the dynamic response characteristics of the soil, this method establishes a complete set of equations including soil dynamic equations, constitutive equations, vibration propagation equations, etc. By numerically solving these equations, it can more accurately simulate and predict the stress-strain state of the surrounding soil during pile foundation construction. This modeling method based on dynamic analysis is more in line with the actual situation than the existing static or quasi-static analysis.

[0071] In general, the method for evaluating the soil squeezing effect of pile driving based on vibration-strain signal analysis proposed in the present invention fully integrates on-site monitoring data and dynamic theory analysis, and can more accurately and comprehensively evaluate the changes in the bearing capacity of the pile foundation. It solves the technical problem that the monitoring data and theoretical analysis results in the prior art are often difficult to effectively integrate, resulting in weak reliability and pertinence of the evaluation results, and it is difficult to provide sufficient basis for engineering design. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A flow chart of the method provided by the present invention. DETAILED DESCRIPTION

[0073] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0074] like Figure 1 FIG. 1 is a flow chart of a method for evaluating the impact of soil squeezing effect of pile sinking on pile foundation load provided by the present invention. The method comprises the following steps:

[0075] S10, installing a plurality of vibration sensors and strain sensors at different depths and distances around the pile foundation, and continuously collecting vibration signals and strain signals during the downward construction of the pile foundation to form a vibration-strain signal group;

[0076] S20, preprocessing the collected vibration-strain signal, including denoising, filtering and signal alignment, to improve data quality;

[0077] S30, according to each signal in the aligned vibration-strain signal group, using a time-frequency analysis method to determine an optimal time window length to capture the characteristics of soil vibration and deformation around the pile foundation;

[0078] S40, using the determined optimal time window length, extracting the time-frequency characteristics of each signal, including amplitude, frequency, phase and strain magnitude, and recording the time-frequency characteristics of all signals as a feature group to be measured;

[0079] S50, establishing a group of dynamic equations, including soil dynamic equations, soil stress-strain relationship equations, soil vibration propagation equations, soil deformation coordination equations, and pile-soil interaction equations;

[0080] S60, solving the dynamic equations to obtain multiple analytical solutions, which are a first analytical solution for describing the vibration propagation characteristics of the soil around the pile foundation, a second analytical solution for describing the stress distribution characteristics of the soil around the pile foundation, a third analytical solution for describing the deformation characteristics of the soil around the pile foundation, a fourth analytical solution for describing the pile-soil interaction characteristics, and a fifth analytical solution for describing the bearing capacity characteristics of the pile foundation;

[0081] S70, establishing a mathematical model of soil squeezing effect of pile sinking based on multiple analytical solutions and initial conditions and boundary conditions of the dynamic equations, using the characteristic group to be measured as input parameters to solve the stress-strain state of the soil around the pile;

[0082] S80, based on the solved stress-strain state of the soil around the pile, calculate the changes of the side friction and end resistance of the pile foundation, and then evaluate the influence of the soil squeezing effect on the bearing capacity of the pile foundation as the evaluation result;

[0083] S90. Based on the evaluation results, calculate the overall bearing capacity change index of the pile foundation, determine the impact of the soil squeezing effect on the pile foundation load, and mark the potential bearing capacity reduction area.

[0084] The specific implementation methods of the above steps are described in detail below:

[0085] In step S10, a plurality of vibration sensors and strain sensors are installed at different depths and distances around the pile foundation to continuously collect vibration signals and strain signals during the pile foundation construction process.

[0086] For vibration signals, an acceleration sensor can be used to measure the vibration acceleration of the soil a(x, t), where x represents the horizontal position coordinate of the sensor and t represents the time coordinate. According to Newton's second law, the vibration acceleration is related to the dynamic response force f of the soil. d (x, t) has the following relationship:

[0087]

[0088] Among them, ρ is the soil density and V is the soil volume.

[0089] For strain signals, strain gauges can be used to measure the strain ε(x, t) of the soil. The relationship between strain and soil displacement u(x, t) is as follows:

[0090]

[0091] By rationally deploying the sensor array, the temporal and spatial distribution information of the vibration and deformation of the soil around the pile foundation can be obtained, providing basic data for subsequent analysis and evaluation.

[0092] In step S20, the collected vibration-strain signal needs to be preprocessed, including denoising, filtering, and signal alignment.

[0093] First, the original signal needs to be denoised. A commonly used method is wavelet denoising, which uses wavelet transform to decompose the signal and remove high-frequency noise components. The expression of wavelet transform is:

[0094]

[0095] Among them, ψ a,b (t) is the wavelet basis function with scale a and translation b, and W(a,b) is the wavelet coefficient. By setting a suitable threshold, the noise component can be effectively removed and the signal quality can be improved.

[0096] Secondly, the signal needs to be filtered. A commonly used method is a bandpass filter, which can retain the frequency band related to soil vibration and deformation and remove irrelevant high and low frequency components. The transfer function of the bandpass filter can be expressed as:

[0097]

[0098] Among them, ω c is the cut-off frequency, and n is the filter order. By adjusting the filter parameters, the ideal frequency band characteristics can be obtained.

[0099] Finally, the signals collected by different sensors need to be time aligned. This can be achieved by time delay compensation, that is, performing the following time shift operation on each signal:

[0100] f a (t) = f(t-τ) a )

[0101] Among them, f a (t) is the aligned signal, τ a is the time delay. By determining the optimal time delay τ a ,The time misalignment caused by propagation delay or acquisition time difference can be eliminated.

[0102] Through the above preprocessing measures, the quality and reliability of the signal can be effectively improved, laying the foundation for subsequent time-frequency analysis.

[0103] In step S30, the optimal time window length is determined by using a time-frequency analysis method according to the aligned vibration-strain signal group. Time-frequency analysis is a very effective signal analysis tool that can simultaneously reflect the characteristics of the signal in the time domain and the frequency domain.

[0104] A commonly used time-frequency analysis method is short-time Fourier transform (STFT), which can be expressed as:

[0105]

[0106] Among them, f(t) is the signal to be analyzed, and w(t) is the window function. STFT can obtain the energy distribution of the signal on the time-frequency plane, thereby reflecting the time-varying characteristics of soil vibration and deformation.

[0107] By performing STFT operation on each sensor signal, its time-frequency characteristic spectrum can be obtained. Combined with the physical process of soil vibration and deformation, it is necessary to determine the optimal time window length T that can fully reflect the soil response characteristics. w The length of this time window determines the time resolution of the subsequent time-frequency feature extraction, which is crucial for accurately describing the dynamic response of soil.

[0108] In step S40, the optimal time window length T determined in step S30 is used. w ,The time-frequency characteristics of each signal are extracted, including amplitude, frequency, phase, and strain magnitude.

[0109] For vibration signals, the following time-frequency characteristic parameters can be extracted:

[0110] A(t,ω)=|STFT(t,v)|

[0111]

[0112] φ(t,ω)=∠STFT(t,ω)

[0113] Among them, A(t,ω) represents the amplitude of the signal on the time-frequency plane, ω(t) represents the instantaneous frequency of the signal, and φ(t,ω) represents the instantaneous phase of the signal. These parameters can fully describe the vibration state of the soil at different time-frequency points.

[0114] For strain signals, it can be directly extracted:

[0115] ε(x,t)

[0116] The time-frequency characteristic parameters of all sensor signals are organized into a characteristic parameter group X = {A, ω, φ, ε} as input data for subsequent analysis.

[0117] In step S50, a set of equations describing the dynamic behavior of pile foundation-soil is established, including the following equations:

[0118] 1. Soil dynamics equation:

[0119]

[0120] Among them, ρ is the soil density, u is the soil displacement, σ is the soil stress tensor, and b is the body force. This equation describes the equation of motion of the soil.

[0121] 2. Soil stress-strain relationship equation:

[0122] σ=D·∈

[0123] Among them, D is the stiffness matrix of soil, ∈ is the strain tensor of soil. This equation describes the constitutive relation of soil.

[0124] 3. Soil vibration propagation equation:

[0125]

[0126] Where c is the wave propagation velocity of the soil. This equation describes the propagation characteristics of the vibration signal in the soil.

[0127] 4. Soil deformation coordination equation:

[0128]

[0129] This equation indicates that soil deformation must satisfy the continuity condition.

[0130] 5. Pile-soil interaction equation:

[0131] p=f(u,∈)

[0132] Where p is the interaction force between the pile foundation and the soil. This equation describes the interaction between the pile foundation and the surrounding soil.

[0133] These equations together constitute a complete set of equations describing the dynamic behavior of pile foundation-soil, laying the foundation for subsequent analysis and solution.

[0134] In step S60, the system of equations established in step S50 is solved to obtain multiple analytical solutions.

[0135] 1. First analytical solution:

[0136] The analytical solution describes the vibration propagation characteristics of the soil around the pile foundation, that is, the propagation law of the vibration signal in the soil in time and space. It can be expressed as:

[0137] u(x,t)=A cos(ωt-kx)

[0138] Among them, A is the amplitude, ω is the angular frequency, and k is the wave number. This analytical solution reflects the propagation characteristics of the wave signal in the soil and provides a basis for evaluating the vibration impact around the pile foundation.

[0139] 2. Second analytical solution:

[0140] This analytical solution describes the stress distribution characteristics of the soil around the pile foundation, that is, the stress state of the soil during the pile foundation construction process. It can be expressed as:

[0141] σ(x,t)=B exp(-αx)sin(ωt-kx+φ)

[0142] Among them, B is the stress amplitude, α is the attenuation coefficient, and φ is the phase. The analytical solution reflects the variation of soil stress with space and time, and provides a basis for evaluating the stress state of the soil around the pile foundation.

[0143] 3. The third analytical solution:

[0144] The analytical solution describes the deformation characteristics of the soil around the pile foundation, that is, the displacement and strain state of the soil during the pile foundation construction process. It can be expressed as:

[0145] ∈(x,t)=C exp(-βx)cos(ωt-kx+θ)

[0146] Among them, C is the strain amplitude, β is the attenuation coefficient, and θ is the phase. The analytical solution reflects the variation of soil deformation with space and time, and provides a basis for evaluating the deformation state of soil around pile foundations.

[0147] 4. The fourth analytical solution:

[0148] The analytical solution describes the characteristics of pile-soil interaction, that is, the interaction force between the pile foundation and the surrounding soil. It can be expressed as:

[0149] p(x,t)=Dexp(-γx)sin(ωt-kx+ψ)

[0150] Among them, D is the amplitude of the interaction force, γ is the attenuation coefficient, and ψ is the phase. The analytical solution reflects the characteristics of the dynamic interaction between the pile foundation and the soil, and provides a basis for analyzing the stress state of the pile foundation.

[0151] 5. The fifth analytical solution:

[0152] The analytical solution describes the characteristics of pile foundation bearing capacity, that is, the change of pile foundation bearing capacity under the soil squeezing effect. It can be expressed as:

[0153]

[0154] in, is the bearing capacity of the pile foundation before construction, Δ Q (t) is the time-varying rate of change of bearing capacity. This analytical solution provides the basis for subsequent bearing capacity assessment.

[0155] These analytical solutions fully reflect the characteristics of various aspects of the pile foundation-soil dynamic system and provide a basis for the subsequent establishment of mathematical models.

[0156] In step S70, a mathematical model of the soil squeezing effect of pile driving is established based on the multiple analytical solutions obtained in step S60 and the initial conditions and boundary conditions of the equation group.

[0157] The characteristic parameter group X to be measured obtained in step S40 is used as input and substituted into the above analytical solution to solve the stress-strain state of the soil around the pile by numerical calculation.

[0158] Specifically, the following mathematical model can be constructed:

[0159]

[0160] in, to They respectively represent the mapping relationship among soil displacement, stress, strain, pile-soil interaction force and pile foundation bearing capacity obtained according to the analytical solution in step S60. By numerically solving these equations, the stress-strain state of the soil around the pile can be obtained, providing a basis for the subsequent bearing capacity evaluation.

[0161] The core of this mathematical model is to use the time-frequency characteristics of the vibration-strain signal to simulate and predict the stress-strain response characteristics of the surrounding soil during pile foundation construction by solving the dynamic equations. The model includes multiple aspects such as soil vibration propagation, stress distribution, deformation characteristics, and pile-soil interaction, and can more accurately reflect the disturbance process of pile foundation construction on the surrounding soil.

[0162] In step S80, based on the stress-strain state of the soil around the pile obtained in step S70, the changes in the side friction and end resistance of the pile foundation are calculated.

[0163] Firstly, the shear strength parameters of the soil around the pile foundation, such as cohesion c and internal friction angle φ, are calculated using the soil strain state ∈, and then according to the classic Mohr-Coulomb strength criterion:

[0164] τ=c+σ n tanφ

[0165] Calculate the side friction Q s Among them, σ n is the normal stress.

[0166] Secondly, the bearing area A at the end of the pile foundation is calculated using the soil stress state σ b and stress distribution σ b , and then according to the formula:

[0167] Q b =σ b A b

[0168] Calculate the end resistance Q b .

[0169] Finally, the calculated changes in side friction and end resistance are used as evaluation results to reflect the influence of the soil squeezing effect of pile sinking on the total bearing capacity of the pile foundation.

[0170] The key to this step is to accurately capture the changing law of the stress-strain state of the soil around the pile foundation, so as to reasonably calculate the change of the pile foundation bearing capacity. The evaluation results obtained provide a basis for the next step of impact analysis.

[0171] In step S90, the overall bearing capacity change index η of the pile foundation is calculated according to the pile foundation bearing capacity change evaluation result obtained in step S80. This index reflects the influence of the soil squeezing effect on the pile foundation bearing capacity and can be expressed as:

[0172]

[0173] In the formula, and are the total bearing capacity of the pile foundation before and after construction, respectively.

[0174] By analyzing the value of η, the influence of the soil squeezing effect on the pile foundation load can be determined. If η is less than -5%, it means that the soil squeezing effect has caused a large reduction in bearing capacity and needs to be taken seriously; if η is between -5% and +5%, it means that the soil squeezing effect has a small influence on the bearing capacity and is acceptable; if η is greater than +5%, it means that the soil squeezing effect has a certain degree of enhancement on the bearing capacity.

[0175] At the same time, it is also necessary to mark the potential bearing capacity reduction area based on the stress-strain distribution of the soil around the pile obtained in step S70, σ(x, t) and ∈(x, t). A certain stress or strain threshold σ can be set c and ∈ c ,When the stress or strain in a local area exceeds these thresholds, it is identified as a potential area of ​​reduced bearing capacity and needs to be focused on. This information helps to take targeted reinforcement measures to ensure that the pile foundation can still meet the design requirements under the soil squeezing effect.

[0176] Threshold σ c and ∈ c It can be determined based on engineering experience and relevant specifications, for example:

[0177] σ c =0.8σ y

[0178] ∈ c =0.01

[0179] Among them, σ y is the yield stress of soil.

[0180] In general, the method proposed by this invention can comprehensively evaluate the impact of pile-sinking soil-squeezing effect on bearing capacity, and provide an important reference for pile foundation design and construction. The whole method involves multiple disciplines, such as soil mechanics, structural dynamics, signal processing, etc., and embodies strong academic and innovative nature.

[0181] Through the detailed description of the above steps S10-S90, it can be seen that this inventive method makes full use of the time-frequency characteristics of the vibration-strain signal, and by establishing a pile foundation-soil dynamics model, simulates and predicts the stress-strain response of the surrounding soil during the pile foundation construction process, and then evaluates the impact of the soil squeezing effect on the pile foundation bearing capacity. This method based on the combination of monitoring data and mechanical analysis can not only quantitatively describe the soil squeezing effect, but also has strong pertinence and operability for engineering applications.

[0182] The sources or acquisition methods of relevant variables are provided below: a) ρ (soil density): Source: obtained through field or laboratory tests. Acquisition method: can be obtained through field testing methods such as the ring knife method and the sand filling method, or calculated in the laboratory through the mass volume ratio.

[0183] b) u (soil displacement): Source: obtained through on-site monitoring. Acquisition method: can be measured using instruments such as displacement sensors and inclinometers.

[0184] c) σ (soil stress tensor): Source: obtained through field tests or theoretical calculations. Acquisition method: can be measured using instruments such as earth pressure cells, or calculated through stress analysis methods.

[0185] d) D (soil stiffness matrix): Source: obtained through laboratory tests or empirical formulas. Acquisition method: The elastic modulus and Poisson's ratio of the soil can be determined through triaxial tests, shear tests, etc., and then the stiffness matrix can be constructed.

[0186] e)∈(soil strain tensor): Source: obtained through field monitoring or theoretical calculation. Acquisition method: can be measured using instruments such as strain gauges, or calculated through displacement gradient.

[0187] f) c (wave propagation velocity): Source: obtained through field tests or empirical formulas. Acquisition method: It can be tested on site using a wave velocity tester, or estimated using empirical formulas based on soil type and physical properties.

[0188] g) p (pile-soil interface interaction force): Source: obtained through field tests or theoretical models. Acquisition method: can be measured using instruments such as pile side friction meters, or calculated using pile-soil interaction models.

[0189] h) A, B, C, D (amplitude parameters): Source: obtained through signal analysis. Acquisition method: Perform time-frequency analysis on the collected vibration-strain signal and extract the corresponding amplitude parameters.

[0190] i) ω (angular frequency), k (wave number), α, β, γ (attenuation coefficient), φ, θ, ψ (phase): Source: obtained through signal analysis and wave theory. Acquisition method: Perform time-frequency analysis on the collected signal and determine these parameters in combination with wave propagation theory.

[0191] j)Q b (Bearing capacity of pile foundation): Source: obtained through field test or theoretical calculation. Acquisition method: can be directly measured through static load test, or theoretically calculated based on soil parameters and pile foundation parameters.

[0192] k) c (cohesion) and φ (internal friction angle): Source: obtained through laboratory tests or field tests. Acquisition method: can be determined through laboratory methods such as triaxial test, direct shear test, or field shear test.

[0193] l)σ n (Normal stress): Source: obtained through field tests or theoretical calculations. Acquisition method: can be measured using an earth pressure cell or calculated using stress analysis methods.

[0194] m)A b (Bearing area of ​​pile foundation end): Source: Determined according to pile foundation design parameters. Acquisition method: Direct measurement or calculation based on pile foundation design drawings.

[0195] n)σ b (Stress distribution at the pile end): Source: obtained through field tests or theoretical calculations. Acquisition method: can be measured using a pile end stress gauge, or calculated through stress transfer theory.

[0196] The accurate acquisition of these variables is crucial to evaluate the impact of pile driving and soil squeezing. In practical applications, it may be necessary to combine multiple test methods and theoretical analysis to determine these parameters to ensure the reliability of the evaluation results.

[0197] It should be noted that the functional relationship f in the pile-soil interaction equation p = f(u,∈) is a complex problem, and its acquisition method involves multiple aspects such as theoretical analysis, experimental research and numerical simulation. I will explain in detail several main methods for obtaining this functional relationship:

[0198] 1. Theoretical model:

[0199] The theoretical model establishes a mathematical expression for pile-soil interaction through mechanical analysis. Commonly used theoretical models include:

[0200] a) Elastic Winkler Model:

[0201] p=k h u

[0202] where k h is the horizontal foundation reaction coefficient.

[0203] b)py curve method:

[0204]

[0205] where p u is the ultimate lateral earth pressure, A is the empirical coefficient, and y is the horizontal displacement.

[0206] The parameters of these theoretical models can be obtained through geotechnical tests or empirical formulas.

[0207] 2. Field test:

[0208] Directly measure the pile-soil interaction relationship through field tests. The main methods include:

[0209] a) Horizontal load test: A horizontal load test is carried out on a single pile to measure the horizontal displacement of the pile and the corresponding soil pressure.

[0210] b) Dynamic pile test: Through the dynamic pile test method, the dynamic response of the pile is analyzed and the pile-soil interaction parameters are inverted.

[0211] c) Centrifuge test: Simulate actual engineering conditions in a centrifuge to measure the pile-soil interaction relationship.

[0212] 3. Indoor model test:

[0213] Small-scale model tests are carried out in the laboratory to study the pile-soil interaction mechanism. Common methods include:

[0214] a) Shear box test: simulates the shear characteristics of the pile-soil interface.

[0215] b) Ring shear test: to study the large deformation characteristics of the pile-soil interface.

[0216] c) Pressure chamber test: study the pile-soil interaction under controlled stress conditions.

[0217] 4. Numerical simulation:

[0218] Finite element, finite difference and other numerical methods are used to simulate the pile-soil interaction process. The main steps include:

[0219] a) Establish soil constitutive models, such as the Mohr-Coulomb model, Drucker-Prager model, etc.

[0220] b) Simulate the pile-soil interface, such as by using contact units or interface elements.

[0221] c) Conduct parametric studies to obtain the pile-soil interaction relationship under different conditions.

[0222] 5. Artificial Intelligence Methods:

[0223] Using machine learning algorithms, the pile-soil interaction model is trained based on a large amount of measured data. The methods include:

[0224] a) Neural network: Construct a multi-layer neural network, input soil parameters and pile geometric parameters, and output interaction forces.

[0225] b) Support vector machine: Based on the existing data, a nonlinear mapping relationship of pile-soil interaction is established.

[0226] c) Genetic algorithm: Optimize the parameters of the pile-soil interaction model.

[0227] 6. Semi-empirical method:

[0228] Combining theoretical analysis and engineering experience, a semi-empirical formula is proposed. For example:

[0229] p=C1·E s ·u+C2·σ′ v ·tanφ·u

[0230] Where C1 and C2 are empirical coefficients, E s is the elastic modulus of soil, σ′ v is the effective vertical stress and φ is the internal friction angle.

[0231] In practical applications, it is usually necessary to use a variety of methods to obtain the pile-soil interaction function relationship:

[0232] 1. First, establish a preliminary function form based on the theoretical model.

[0233] 2. Then, obtain key parameters through field tests or indoor tests.

[0234] 3. Use numerical simulation methods to conduct parametric research and expand the scope of application of the function.

[0235] 4. If there is enough data, you can consider using machine learning methods to optimize the model.

[0236] 5. Finally, the model is modified and calibrated based on engineering experience.

[0237] It should be noted that the pile-soil interaction relationship is affected by many factors, such as soil type, stress state, pile geometry, etc. Therefore, the obtained functional relationship should be targeted at specific engineering conditions, and its scope of application should be noted when used. In actual engineering, field verification and adjustment may be required to ensure the accuracy and reliability of the model.

[0238] A second aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores program instructions, and when the program instructions are executed, they are used to execute the above-mentioned method for evaluating the influence of pile driving and soil squeezing effect on pile foundation load.

[0239] A third aspect of the present invention provides a system for evaluating the impact of soil squeezing effect of pile driving on pile foundation load, which includes the above-mentioned computer-readable storage medium.

[0240] Specifically, the principle of the present invention is:

[0241] 1. Comprehensively describe the dynamic response of soil using multi-point dynamic monitoring data: During the construction of pile foundation, the surrounding soil will experience complex vibration and deformation responses. The method of the present invention deploys multiple vibration sensors and strain sensors around the pile foundation to continuously collect dynamic response signals of soil in time and space. Compared with existing single-point or small amount of monitoring data, this multi-point monitoring method can more comprehensively capture the spatiotemporal distribution characteristics of soil dynamic response, laying a more reliable foundation for subsequent analysis.

[0242] 2. Use time-frequency analysis technology to extract characteristic parameters to describe soil response: The dynamic response of soil often has obvious time-varying characteristics, and it is difficult to fully reflect its dynamic characteristics by relying solely on time domain analysis. The method of the present invention uses time-frequency analysis technology, such as short-time Fourier transform and wavelet transform, to extract time-frequency characteristic parameters such as amplitude, frequency, and phase from vibration-strain signals. These parameters can more comprehensively describe the vibration and deformation characteristics of soil in the time-frequency domain.

[0243] 3. Establish a comprehensive dynamic analysis model to simulate the interaction between pile foundation and soil: Based on the time-frequency characteristic parameters, the method of the present invention establishes a complete set of equations describing the dynamic behavior of pile foundation and soil, including soil dynamic equations, stress-strain relationship equations, vibration propagation equations, etc. By solving these equations, the stress-strain distribution of the soil around the pile foundation can be obtained, providing a basis for subsequent bearing capacity evaluation. This modeling method based on dynamic analysis is more in line with actual engineering conditions than existing static or quasi-static analysis.

[0244] In order to better understand and implement the present invention, an embodiment of a specific application scenario of the present invention is provided below: A high-rise building project is located in a coastal area, and the foundation adopts reinforced concrete pile foundation. Due to the complex geological conditions, a more serious pile sinking and soil squeezing effect may occur during the construction process, which has a certain impact on the bearing capacity of the pile foundation. In order to evaluate the impact of the soil squeezing effect on the safety of the project, the construction unit decided to adopt the pile foundation bearing capacity assessment method based on vibration-strain signal analysis proposed in the present invention to conduct detailed monitoring and analysis of the project.

[0245] 1. On-site monitoring installation

[0246] According to the requirements of the method of the present invention, a total of 12 vibration sensors and 12 strain sensors are installed at different depths and distances around the pile foundation. The specific arrangement is as follows:

[0247] Vibration sensor arrangement: 4 sensors are set at the top (buried depth 2m), middle (buried depth 10m) and bottom (buried depth 20m) of the pile foundation, respectively, at horizontal distances of 1m, 2m, 3m and 4m around the pile foundation.

[0248] Strain sensor arrangement: consistent with the vibration sensor arrangement position, 4 sensors are set at the top, middle and bottom of the pile foundation, with horizontal distances of 1m, 2m, 3m and 4m respectively.

[0249] Such a sensor arrangement scheme can fully obtain the vibration and strain response information of the soil around the pile foundation at different depths and positions, laying the foundation for subsequent analysis and evaluation.

[0250] 2. Signal preprocessing

[0251] The vibration acceleration signal a(x, t) and strain signal ε(x, t) collected on site are preprocessed, including denoising, filtering and time alignment.

[0252] First, the original signal is subjected to wavelet denoising. The Daubechies 4th-order wavelet basis function is selected, and after 5 layers of wavelet decomposition, the high-frequency components are filtered out to obtain the denoised signal. This step can effectively remove the influence of external vibration noise on the measurement data.

[0253] Secondly, the denoised signal is bandpass filtered. The cutoff frequency of the filter is set to 1Hz and 100Hz, which can retain the main frequency bands related to soil vibration and deformation and remove irrelevant high and low frequency components.

[0254] Finally, the signals collected by different sensors are time-aligned. Through cross-correlation analysis, the optimal time delay τ of each signal relative to the reference signal is determined. a , and corrects it. This can eliminate the time misalignment caused by propagation delay or acquisition time difference.

[0255] After the above preprocessing, high-quality vibration-strain signal data were obtained, laying the foundation for subsequent time-frequency analysis.

[0256] 3. Time-frequency feature extraction

[0257] According to step S30, short-time Fourier transform (STFT) is used to perform time-frequency analysis on the preprocessed signal to determine the optimal time window length T w After analysis, the optimal time window length T is determined w =0.5s, which can better capture the instantaneous characteristics of soil vibration response.

[0258] Next, using the determined T w ,The time-frequency characteristic parameters of the vibration-strain signal of each monitoring point are extracted, including amplitude A(t,ω), frequency ω(t), phase φ(t,ω) and strain ε(x,t), etc. These time-frequency characteristic parameters constitute the characteristic parameter group X, which provides input for the subsequent analysis model.

[0259] 4. Establishment of dynamic analysis model

[0260] According to step S50, a complete set of equations describing the dynamic behavior of pile foundation-soil is established, including:

[0261] (1) Soil dynamics equation:

[0262]

[0263] (2) Soil constitutive equation:

[0264] σ=D·∈

[0265] (3) Soil vibration propagation equation:

[0266]

[0267] (4) Soil deformation coordination equation:

[0268]

[0269] (5) Pile-soil interaction equation:

[0270] p=C1·E s ·u+C2·σ′ v ·tanφ·u

[0271] These equations together describe the behavior characteristics of the pile-soil dynamic system during pile foundation construction.

[0272] According to step S60, the above equations are solved to obtain five analytical solutions, which respectively describe the vibration propagation characteristics, stress distribution characteristics, deformation characteristics, pile-soil interaction characteristics and pile foundation bearing capacity characteristics of the soil. Take the analytical solution of soil stress distribution as an example:

[0273] σ(x,t)=B exp(-αx)sin(ωt-kx+φ)

[0274] Among them, B is the stress amplitude, α is the attenuation coefficient, and φ is the phase. The analytical solution reflects the variation of soil stress with space and time.

[0275] 5. Carrying capacity assessment

[0276] Based on the dynamic analysis model established in step S70, the characteristic parameter group X obtained by field monitoring is used as input, and the stress-strain distribution of the soil around the pile foundation σ(x, t) and ∈(x, t) is obtained by numerically solving the equation group.

[0277] It can be seen from the figure that during the pile foundation construction, the soil stress and strain did undergo large temporal and spatial changes. This non-uniform stress-strain distribution will inevitably affect the side friction and end resistance of the pile foundation.

[0278] According to step S80, the lateral friction Q of the pile foundation is calculated using the above soil stress-strain state. s and end resistance Q b The results show that under the soil squeezing effect, the shear strength parameters c and φ of the soil near the bottom of the pile foundation are significantly reduced, resulting in the lateral friction resistance Q s At the same time, the stress concentration of the soil at the end of the pile foundation is also weakened, and the end resistance Q b That’s down about 8%.

[0279] Comprehensive calculation shows that the total bearing capacity of the pile foundation of this project is Q b Under the soil squeezing effect, it dropped by about 10%, that is, the bearing capacity change index η = -10%.

[0280] According to step S90, it is considered that the reduction in bearing capacity has exceeded the acceptable range and reinforcement measures need to be taken. At the same time, it can be seen from the soil stress-strain distribution diagram that the soil strain near the bottom of the pile foundation is large, which is the main reason for the reduction in bearing capacity and needs to be paid special attention to.

[0281] Based on the above analysis results, the following reinforcement measures are proposed:

[0282] (1) Appropriately increase the number of pile foundations to improve the overall bearing capacity;

[0283] (2) Add micropiles or soil nails near the bottom of the pile foundation to improve the local soil strength;

[0284] (3) Use high-strength concrete or prestressed technology to improve the bearing capacity of single piles.

[0285] By implementing the above reinforcement measures, it is expected that the total bearing capacity of the pile foundation can be restored to the original design level, ensuring the safety and reliability of the engineering structure.

[0286] 6. Summary

[0287] By adopting the pile-sinking soil-squeezing effect evaluation method based on vibration-strain signal analysis proposed in this invention, a comprehensive evaluation of the pile foundation bearing capacity change of the project was carried out. The results show that during the pile foundation construction process, the vibration and deformation response of the surrounding soil did undergo significant changes, resulting in a significant reduction in the pile foundation bearing capacity.

[0288] Compared with the existing empirical analysis methods, the method of the present invention makes full use of field monitoring data and combines advanced signal processing and dynamic analysis technology to more accurately describe and predict the dynamic behavior of pile foundation-soil. By quantitatively calculating the bearing capacity change index and analyzing the potential reduction area, it provides a more scientific technical basis for engineers and helps to take targeted reinforcement measures.

[0289] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for evaluating the impact of pile sinking soil squeezing effect on pile foundation load, characterized in that: The following steps are involved: S10, installing a plurality of vibration sensors and strain sensors at different depths and distances around the pile foundation, and continuously collecting vibration signals and strain signals during the downward construction of the pile foundation to form a vibration-strain signal group; S20, preprocessing the collected vibration-strain signal, including denoising, filtering and signal alignment, to improve data quality; S30, according to each signal in the aligned vibration-strain signal group, using a time-frequency analysis method to determine an optimal time window length to capture the characteristics of soil vibration and deformation around the pile foundation; S40, using the determined optimal time window length, extracting the time-frequency characteristics of each signal, including amplitude, frequency, phase and strain magnitude, and recording the time-frequency characteristics of all signals as a feature group to be measured; S50, establishing a group of dynamic equations, including soil dynamic equations, soil stress-strain relationship equations, soil vibration propagation equations, soil deformation coordination equations, and pile-soil interaction equations; S60, solving the group of dynamic equations to obtain multiple analytical solutions, which are a first analytical solution for describing the vibration propagation characteristics of the soil around the pile foundation, a second analytical solution for describing the stress distribution characteristics of the soil around the pile foundation, a third analytical solution for describing the deformation characteristics of the soil around the pile foundation, a fourth analytical solution for describing the pile-soil interaction characteristics, and a fifth analytical solution for describing the bearing capacity characteristics of the pile foundation; S70, establishing a mathematical model of soil squeezing effect of pile sinking according to the multiple analytical solutions and the initial conditions and boundary conditions of the dynamic equations, and solving the stress-strain state of the soil around the pile with the characteristic group to be measured as input parameters; S80, based on the solved stress-strain state of the soil around the pile, calculate the changes of the side friction and end resistance of the pile foundation, and then evaluate the influence of the soil squeezing effect on the bearing capacity of the pile foundation as the evaluation result; S90. Based on the evaluation results, calculate the overall bearing capacity variation index of the pile foundation, determine the influence of the soil squeezing effect on the pile foundation load, and mark the potential bearing capacity reduction area.

2. The method for evaluating the impact of pile-sinking soil-squeezing effect on pile foundation load according to claim 1, characterized in that: The soil dynamics equation is specifically: Where ρ is soil density; u is soil displacement vector; t is time; is the divergence operator; σ is the stress tensor; b is the unit mass body force vector.

3. The method for evaluating the impact of pile-sinking soil-squeezing effect on pile foundation load according to claim 2, characterized in that: The soil stress-strain relationship equation is specifically: σ=D·∈; Where D is the stiffness matrix; ∈ is the strain tensor.

4. The method for evaluating the impact of soil squeezing effect of pile sinking on pile foundation load according to claim 3 is characterized in that: The soil vibration propagation equation is specifically: Where c is the wave propagation speed; is the Laplace operator.

5. The method for evaluating the impact of soil squeezing effect of pile sinking on pile foundation load according to claim 4, characterized in that: The soil deformation coordination equation is specifically:

6. The method for evaluating the impact of soil squeezing effect of pile sinking on pile foundation load according to claim 5, characterized in that: The pile-soil interaction equation is specifically: p=C1·E s ·u+C2·σ′ v ·thinφ·u; Where p is the pile-soil interface interaction force; C1 and C2 are empirical coefficients, E s is the elastic modulus of soil, σ′ v is the effective vertical stress and φ is the internal friction angle.

7. The method for evaluating the impact of soil squeezing effect of pile sinking on pile foundation load according to claim 6, characterized in that: The multiple analytical solutions are: The first analytical solution describes the vibration propagation characteristics of the soil around the pile foundation, that is, the propagation law of the vibration signal in the soil in time and space, which is specifically expressed as: u(x,t)=A cos(ωt-kx); In the formula, A is the amplitude, ω is the angular frequency, and k is the wave number; The second analytical solution describes the stress distribution characteristics of the soil around the pile foundation, that is, the stress state of the soil during the pile foundation construction process, which is specifically expressed as: σ(x,t)=B exp(-αx)sin(ωt-kx+φ); In the formula, B is the stress amplitude, α is the attenuation coefficient, and φ is the phase; The third analytical solution describes the deformation characteristics of the soil around the pile foundation, that is, the displacement and strain state of the soil during the pile foundation construction process, which is specifically expressed as: ∈(x,t)=C exp(-βx)cos(ωt-kx+θ); In the formula, C is the strain amplitude, β is the attenuation coefficient, and θ is the phase; The fourth analytical solution describes the characteristics of pile-soil interaction, that is, the interaction force between the pile foundation and the surrounding soil, which is specifically expressed as: p(x,t)=D exp(-γx)sin(ωt-kx+ψ); Where D is the amplitude of the interaction force, γ is the attenuation coefficient, and ψ is the phase; The fifth analytical solution describes the characteristics of pile foundation bearing capacity, that is, the change of pile foundation bearing capacity under the soil squeezing effect, which is specifically expressed as: in, is the bearing capacity of the pile foundation before construction, Δ Q (t) is the time-varying rate of change of bearing capacity.

8. The method for evaluating the impact of soil squeezing effect of pile sinking on pile foundation load according to claim 7, characterized in that: The overall bearing capacity variation index of the pile foundation is specifically: In the formula, and are the total bearing capacity of the pile foundation before and after construction, respectively.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program instructions, which, when executed, are used to execute the method for evaluating the influence of soil squeezing effect of pile driving on pile foundation load as described in any one of claims 1 to 8.

10. A system for evaluating the impact of pile sinking soil squeezing effect on pile foundation load, characterized in that: A computer-readable storage medium comprising the computer-readable storage medium of claim 9.

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