Method and system for damage determination of steel pipe pile high-pile wharf

Abstract

The application provides a steel pipe pile high-pile wharf damage judgment method and system, relates to the steel pipe pile high-pile wharf damage judgment technical field, and the stiffness matrix of the whole stiffness characteristic of the wharf is constructed according to the wharf design parameter, the matrix is spectrally decomposed under the healthy state, the obtained eigenvalue set and eigenvector space are defined as the reference spectrum and reference vector space respectively, and the nondestructive reference is established; for the to-be-measured state, the current spectrum and current vector space thereof are obtained through the same process, the Jensen-Shannon divergence between the current spectrum and the reference spectrum is calculated to generate the global damage index for quantitatively evaluating the overall stiffness degradation degree of the structure; if the index is out of limit, the deviation degree of the vector space is further analyzed through the projection operation, and the abnormal deviation component is reversely mapped to the physical coordinate, so that the accurate spatial positioning of the damage is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel pipe pile high-pile wharf damage determination, in particular to a steel pipe pile high-pile wharf damage determination method and system. BACKGROUND

[0002] As a core component of port infrastructure, the long-term safe operation of the steel pipe pile high-pile wharf is of great importance. Due to the long-term effects of complex factors such as ship impact, wave cyclic load, and environmental corrosion, the wharf structure will inevitably accumulate damage. Therefore, accurate and efficient damage determination of the wharf health condition is crucial for preventing catastrophic accidents and developing scientific maintenance strategies, which has great economic and safety significance. Traditional damage determination methods mainly rely on periodic manual visual inspection and special detection. This method is not only subjective and time-consuming, but also difficult to detect early hidden damage in the structure.

[0003] To overcome the limitations of manual inspection, existing technologies generally use methods based on sensor monitoring and physical model analysis. The first method involves placing sensors on the structure to monitor its vibration response and analyzing changes in dynamic characteristics such as frequency and mode shape to infer damage. However, this method is highly sensitive to environmental disturbances such as temperature and load changes, and can only provide qualitative judgments about whether damage has occurred, making it difficult to quantify the extent of damage and accurately locate the damage location. The other method relies on establishing a detailed finite element model and repeatedly comparing the model prediction results with the measured data to assess the structure's state. This method is computationally complex, and its accuracy highly depends on the consistency between the model itself and the real structure. Small errors in model parameters can lead to misjudgment, making it difficult to reliably apply in practical engineering.

[0004] The fundamental deficiency of the above-mentioned existing technologies is that they have not established a quantitative determination benchmark that does not rely on subjective experience and effectively eliminates environmental and operational variable disturbances. The vibration monitoring method cannot extract the essential characteristics caused solely by structural stiffness degradation from the mixed response signals. The finite element method is plagued by the confusion between model errors and structural damage, making it impossible to accurately separate and quantify damage.

[0005] The above information disclosed in the background section is only used to enhance the understanding of the background of the present disclosure, and therefore it can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0006] The purpose of the present application is to provide a steel pipe pile high-pile wharf damage determination method and system to solve the problems raised in the background.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] A steel pipe pile high-pile wharf damage determination method, the specific steps comprising:

[0009] Step 1: According to the current data parameters of the target steel pipe pile high-pile wharf, an abstract mathematical object representing its overall mechanical properties is constructed, which is a stiffness matrix based on the current data parameters of each unit of the wharf, that is, the geometric topology, material constants and boundary constraint conditions of the high-pile wharf structure are confirmed through a mapping relationship;

[0010] Step 2: Perform spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf in a healthy and undamaged state to decompose it into a set of standard orthogonal basis vectors and their corresponding scalar weights. Arrange all scalar weights in order and define them as the reference spectrum, and compose the reference vector space with the set of standard orthogonal basis vectors;

[0011] Step 3: Perform the same spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf to obtain the current spectrum and the current vector space. Calculate the distance between the current spectrum and the reference spectrum in the sense of probability statistics to generate a global damage index;

[0012] Step 4: If the global damage index exceeds the preset threshold, it is determined that damage has occurred. Calculate the deviation of each standard orthogonal basis vector in the current vector space from the corresponding standard orthogonal basis vector in the reference vector space through projection operation. Calculate the positioning score of each unit based on the deviation of all standard orthogonal basis vectors. The physical space coordinates corresponding to the unit with the highest positioning score are determined as the damage location, thereby achieving accurate positioning.

[0013] Further, the logic for constructing an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high-pile wharf based on its data parameters is as follows:

[0014] Discretize the entire steel pipe pile high-pile wharf structure into multiple finite element model units, which include pile units for simulating steel pipe piles, beam units for simulating cross beams, and plate units for simulating faceplates;

[0015] The data parameters include the geometric topology, material constants and boundary constraint conditions of all units in the target steel pipe pile high-pile wharf. The geometric topology includes geometric dimensions and spatial layout distances, which are defined by node coordinates and unit connection relationships in the finite element model units. The material constants include elastic modulus and Poisson's ratio. The boundary constraint conditions simulate the pile-soil interaction by setting the equivalent spring stiffness of the pile bottom soil;

[0016] Based on the geometric dimensions and material constants of each unit, calculate its unit stiffness matrix in accordance with the principles of structural mechanics. For pile units, the geometric dimensions are pile length, diameter and wall thickness. For beam and plate units, the geometric dimensions are their cross-sectional dimensions;

[0017] According to the connection relationship between the node coordinates and the units, the stiffness matrix of all units is assembled into an initial overall stiffness matrix of the steel pipe pile high-pile wharf structure, and the initial overall stiffness matrix is subjected to boundary condition processing to eliminate rigid displacement, so as to finally generate a symmetric positive definite stiffness matrix.

[0018] Further, the logic of performing spectral analysis on the stiffness matrix of the high-pile wharf in a healthy and undamaged state is as follows:

[0019] The stiffness matrix is subjected to spectral decomposition to obtain a set of standard orthogonal basis vectors and eigenvalues corresponding to each standard orthogonal basis vector, wherein the eigenvalues are scalar weights, each eigenvalue is arranged in descending order to form an eigenvalue sequence serving as a reference spectrum, and the set of standard orthogonal basis vectors is defined as a reference vector space.

[0020] Further, the calculation of the global damage index is obtained based on the divergence measure of the spectral-based probability distribution, and specifically includes:

[0021] The reference spectrum is defined as , and the current spectrum is defined as , represents the current time, is a transpose symbol;

[0022] The eigenvalue sequences of the reference spectrum and the current spectrum are normalized into probability distributions, wherein the calculation formulas of the probability distribution of the reference spectrum and the probability distribution of the current spectrum are as follows:

[0023] ;

[0024] wherein, is to prevent division by zero constant, , , and , respectively represent the scalar weight ranked in the th position in the reference spectrum, the scalar weight ranked in the th position in the current spectrum, , is the total number of eigenvalues in the eigenvalue sequence, and are the probability values of the scalar weight ranked in the th position in the reference spectrum and the scalar weight ranked in the th position in the current spectrum after normalization;

[0025] The intermediate distribution is calculated, and the global damage index at the current time is calculated using the Jensen-Shannon divergence:

[0026] ;

[0027] wherein, is the global damage index at the current time, whose value range is , and the greater the value is, the higher the damage degree is, and the logarithm with base 2 makes , is a preset constant to avoid the denominator being 0.

[0028] Further, the guarantee criterion value of the standard orthogonal basis vector corresponding to the i-th scalar weight of the current spectrum is calculated :

[0029] ;

[0030] wherein, is the standard orthogonal basis vector corresponding to the i-th scalar weight of the reference spectrum in the reference vector space, is the standard orthogonal basis vector corresponding to the i-th scalar weight of the current spectrum in the current vector space, represents the inner product of vectors, and the absolute value is used to eliminate the sign uncertainty, represents the L2 norm;

[0031] The deviation degree of the standard orthogonal basis vector corresponding to the i-th scalar weight of the current spectrum is defined as: wherein ;

[0032] The positioning score of each unit j at the current time is calculated by using the pre-calibrated unit sensitivity matrix , and the formula is:

[0033] ;

[0034] wherein, is the projection coefficient of the standard orthogonal basis vector ranked in the i-th position to the j-th unit, and the absolute value is used to eliminate the projection sign cancellation effect, and j is the index of the unit in the target steel pipe pile high-pile wharf; The unit with the highest positioning score

[0035] is determined as the damage position, and the damage positioning is realized by combining the node coordinates of the unit and the geographical mapping relationship of the actual structure. Further, the determination of damage occurrence also includes a confirmation process in the time domain, that is, the exponential weighted moving average filtering is performed on

[0036] to obtain the smoothed global damage index:

[0037] ; ​​

[0038] in, The smoothed global damage index. for The smoothed global damage index at time step 1. Forgetting factor, The sampling interval;

[0039] when When the number of consecutive samplings exceeding the preset threshold reaches N, a damage alarm is triggered, where N is a preset positive integer greater than 1.

[0040] Furthermore, the logic for obtaining the preset threshold is as follows: multiple measurements are performed on the target steel pipe pile high pile wharf in a healthy and undamaged state to obtain a series of historical data of global damage indices to form a historical dataset. The mean and standard deviation of the historical dataset are calculated, and the mean plus three times the standard deviation is used as the preset threshold.

[0041] The present invention also provides a damage assessment system for high-pile steel pipe pile wharves, the system being used to execute the above-described damage assessment method for high-pile steel pipe pile wharves, comprising:

[0042] The matrix construction module is used to construct an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high pile wharf based on the current data parameters of the target steel pipe pile high pile wharf. This abstract mathematical object is a stiffness matrix, which is based on the current data parameters of each unit of the wharf, that is, determined by the geometric topology, material constants and boundary constraints of the high pile wharf structure through mapping relationships.

[0043] The data analysis module is used to perform spectral analysis on the stiffness matrix of the target steel pipe pile high pile wharf in a healthy and undamaged state, so as to decompose it into a set of orthogonal basis vectors and their corresponding scalar weights, arrange all the scalar weights in order and define them as the reference spectrum, and form the reference vector space by the set of orthogonal basis vectors.

[0044] The damage calculation module is used to perform the same spectral analysis on the stiffness matrix of the target steel pipe pile high pile wharf, obtain the current spectrum and the current vector space, and generate a global damage index by calculating the distance between the current spectrum and the reference spectrum in a probabilistic statistical sense.

[0045] The location determination module is used to determine that damage has occurred if the global damage index exceeds a preset threshold. It calculates the deviation of each orthogonal basis vector in the current vector space from the corresponding orthogonal basis vector in the reference vector space through projection operation. Based on the deviation of all orthogonal basis vectors, it calculates the positioning score of each unit and determines the physical space coordinates of the unit with the highest positioning score as the damage location, thereby achieving accurate positioning.

[0046] Compared with the prior art, the beneficial effects of the present invention are:

[0047] The present application converts the healthy physical state into a stable mathematical benchmark defined by the benchmark spectrum and the benchmark vector space by constructing an abstract mathematical object (stiffness matrix) representing the structural overall stiffness characteristics and performing spectral decomposition, which fundamentally distinguishes from the vibration frequency susceptible to environmental interference or the finite element result depending on subjective modeling in the traditional method, and it captures the inherent nature of the structural stiffness distribution, laying a reliable foundation for subsequent accurate comparison;

[0048] The present application generates a global damage index by calculating the distance (Jensen-Shannon divergence) between the current spectrum and the benchmark spectrum in the sense of probability statistics, which can sensitively perceive the overall stiffness distribution and subtle deviation, and express the deviation as a value between 0 and 1 with clear physical meaning, i.e., the global damage index, thereby realizing the leap from qualitative judgment to quantitative evaluation of damage degree and effectively solving the problem that the prior art cannot quantify the damage degree;

[0049] The present application analyzes the directional deviation of the corresponding vectors in the current vector space and the benchmark vector space through mathematical projection operation, and reversely maps the vector components with abnormally high deviation degree back to their corresponding physical space coordinates, so that the technical scheme can accurately indicate the specific position of damage occurrence, and this mapping mechanism from mathematical space anomaly to physical space positioning does not depend on the personal experience judgment of engineers and avoids the uncertainty of complex model correction, thereby realizing accurate and objective positioning of the damage position and providing clear guidance for subsequent targeted maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 It is a schematic diagram of the overall method of the present application;

[0051] Figure 2 It is a fitting curve graph of the current probability value-global damage index of the present application;

[0052] Figure 3 It is a fitting curve graph of the intermediate distribution-global damage index of the present application;

[0053] Figure 4 It is a scatter plot of the current probability value-global damage index of the present application;

[0054] Figure 5 It is a line-column graph of the current probability value-intermediate distribution-global damage index of the present application;

[0055] Figure 6 It is a whole system module flow chart of the present application. DETAILED DESCRIPTION

[0056] In order to make the objects, technical solutions and advantages of the present application clearer, further detailed description will be made to the present application in combination with specific embodiments.

[0057] It should be noted that, unless otherwise defined, technical terms or scientific terms used in the present application should be understood as their common meanings to those skilled in the art to which the present application pertains. The terms "first", "second" and similar terms used in the present application do not represent any order, number or importance, but are only used to distinguish different components. The terms "include", "contain" and similar terms mean that the components or objects listed before the terms cover the components or objects listed after the terms and their equivalents, without excluding other components or objects. The terms "connect" or "connected" and similar terms do not mean physical or mechanical connection, but can include electrical connection, whether direct or indirect. The terms "upper", "lower", "left", "right" and the like only represent relative positional relationships, which can change accordingly when the absolute positions of the described objects change.

[0058] Embodiment:

[0059] Please refer to Figures 1-5 The present application provides a technical solution:

[0060] A steel pipe pile high-pile wharf damage determination method, the specific steps comprising:

[0061] Step 1: According to the current data parameters of the target steel pipe pile high-pile wharf, an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high-pile wharf is constructed, which is a stiffness matrix based on the current data parameters of each unit of the wharf, i.e. the geometric topology, material constants and boundary constraint conditions of the high-pile wharf structure are confirmed through a mapping relationship;

[0062] The logic for constructing an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high-pile wharf based on the data parameters of the target steel pipe pile high-pile wharf is:

[0063] The entire steel pipe pile high-pile wharf structure is discretized into a plurality of finite element model units, including pile units for simulating steel pipe piles, beam units for simulating cross beams, and plate units for simulating faceplates;

[0064] The continuous mechanical response in the actual structure is approximated to the response at a finite number of discrete unit nodes through discretization processing, realizing the conversion from infinite degrees of freedom to finite degrees of freedom. Nodes are set at key positions of the structure, including the top, bottom and intermediate segment points of the steel pipe pile, the end and middle of the cross beam, and the corner points and edge midpoints of the faceplate. Each node has six degrees of freedom, including three translational degrees of freedom and three rotational degrees of freedom. The node coordinates accurately record the spatial geometric form of the structure.

[0065] According to the structural characteristics of the steel pipe pile high-pile wharf, differentiated unit types are adopted, in which a three-dimensional beam element is used to simulate the pile element, each element is defined by two nodes, axial, bending, shear and torsional deformation are considered, and the bending and torsional combined deformation of the steel pipe pile under complex loads such as waves and water flow can be accurately reflected; the beam element also adopts a three-dimensional beam element, and the bending and shear effects are mainly considered; the plate element adopts a shell element to simulate the concrete slab, and both the in-plane stiffness and the out-of-plane bending stiffness are considered, and the mechanical behavior of the slab under vehicle load and cargo load can be accurately reflected;

[0066] After the geometric discretization is completed, material properties are assigned to each element, based on field sampling and laboratory test results, the elastic modulus and Poisson's ratio of steel are input for the steel pipe pile element, and the corresponding material parameters of concrete are input for the concrete slab and beam elements, these material constants will directly participate in the calculation process of the element stiffness matrix, and special attention should be paid to the simulation of boundary conditions, through pile foundation static load test in the field, the key parameters of pile-soil interaction are obtained, which are converted into equivalent spring stiffness and applied to the pile bottom node, so as to accurately simulate the actual constraint condition of pile foundation and foundation;

[0067] After obtaining the complete discrete model, the system assembly of the stiffness matrix is started, based on the principle of direct stiffness method in structural mechanics, first, the element stiffness matrix of each element in the local coordinate system is calculated, for the beam element, the coupling effects of axial deformation, bending deformation, shear deformation and torsional deformation need to be considered; for the plate element, the combined effects of in-plane tension, in-plane shear and bending torsional deformation need to be considered, then according to the node connection relationship, all element stiffness matrices are converted from local coordinate system to global coordinate system through coordinate transformation, and the initial overall stiffness matrix is assembled according to the node freedom number system. This assembly process ensures the balance of node force and the coordination of displacement;

[0068] The data parameters include the geometric topology, material constants and boundary constraint conditions of all elements in the target steel pipe pile high-pile wharf, the geometric topology includes geometric dimensions and spatial layout spacing, which is defined by the node coordinates in the finite element model element and the element connection relationship; the material constants include the elastic modulus and Poisson's ratio; the boundary constraint condition is simulated by setting the equivalent spring stiffness of the pile bottom soil to simulate the pile-soil interaction;

[0069] The node coordinates in the geometric topology define the overall size and bandwidth of the stiffness matrix, the element connection relationship defines the force transmission path, and directly affects the distribution characteristics of the overall stiffness of the structure, the diameter, wall thickness and other parameters of the steel pipe pile not only affect the cross-sectional stiffness, but also relate to the local stability;

[0070] The elastic modulus in the material constant represents the ability of the material to resist elastic deformation, which is the core parameter of the stiffness matrix, and the Poisson's ratio reflects the transverse deformation characteristics of the material, which is particularly critical for stress distribution analysis of plate and shell structures; the equivalent spring stiffness in the boundary constraint condition is determined based on the pile-soil interaction theory such as the m method or the p-y curve method, and the spring stiffness value is obtained by inverting the geological survey data and soil test results, which avoids both the excessive simplification of fixed constraints and the unreasonable increase of degrees of freedom;

[0071] Based on the geometric dimensions and material constants of each unit, the unit stiffness matrix is calculated following the principles of structural mechanics. For pile units, the geometric dimensions are pile length, diameter, and wall thickness. For beam and plate units, the geometric dimensions are their cross-sectional dimensions.

[0072] The stiffness matrix of the pile unit is established based on the Timoshenko beam theory or the Euler-Bernoulli beam theory, which considers the coupling effects of axial deformation, bending deformation, shear deformation, and torsional deformation and calculates geometric properties such as cross-sectional area, moment of inertia, and polar moment of inertia through sectional parameters (diameter, wall thickness).

[0073] The stiffness matrix of the beam unit is also based on beam theory, but it is simplified according to the actual stress characteristics of the beam, focusing on bending stiffness and shear stiffness while ignoring the influence of secondary factors. The stiffness matrix of the plate unit is established based on the Mindlin plate theory or Kirchhoff plate theory, which considers the combined effects of in-plane tension, in-plane shear, and bending torsional deformation, and calculates the cross-sectional stiffness matrix through the thickness parameter.

[0074] According to the connection relationship between node coordinates and units, the stiffness matrices of all units are assembled into the initial overall stiffness matrix of the steel pipe pile high-pile wharf structure, and the initial overall stiffness matrix is processed according to the boundary constraint conditions to eliminate rigid displacement, and finally a symmetric positive definite stiffness matrix is generated.

[0075] The assembly process of the overall stiffness matrix is based on the principle of direct stiffness method, which integrates the stiffness matrices of each unit in the global coordinate system into the overall matrix according to the node connection relationship. This process requires the establishment of a complete node degree of freedom numbering system to ensure that each unit contributes correctly to the corresponding position of the overall matrix. After assembly, the overall stiffness matrix is modified according to the boundary conditions to eliminate rigid body displacement modes, and finally a symmetric positive definite overall stiffness matrix is generated.

[0076] The assembly of the initial global stiffness matrix embodies the core concept of the finite element method, including the direct stiffness method principle, coordinate transformation technique and storage optimization strategy. The direct stiffness method principle is based on the node balance condition and displacement compatibility condition, which assembles the element stiffness matrix according to the node freedom degree number to the corresponding position of the global matrix. The coordinate transformation technique transforms the stiffness matrix of each element in the local coordinate system to the global coordinate system through the transformation matrix, ensuring the objectivity of the mechanical response. The storage optimization strategy uses the symmetry, sparsity and strip distribution characteristics of the global stiffness matrix to reduce the demand for computing resources by using compression storage technology;

[0077] The rigid displacement is eliminated to prevent the stiffness matrix from being singular, and the boundary condition is introduced into the method. For fixed constraints, the corresponding row and column related to the freedom degree are directly deleted. For spring constraints, the spring stiffness value is added to the diagonal elements of the global stiffness matrix.

[0078] The symmetry of the symmetric positive definiteness is derived from the reciprocal theorem of work, which is a basic requirement of elasticity. The positive definiteness ensures that the system strain energy is always positive, which meets the physical reality and provides a mathematical guarantee for the subsequent spectral analysis that the eigenvalues are all positive real numbers.

[0079] Step 2: Perform spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf in the healthy and undamaged state to decompose it into a set of standard orthogonal basis vectors and their corresponding scalar weights. Arrange all the scalar weights in order and define them as the reference spectrum. The set of standard orthogonal basis vectors forms the reference vector space.

[0080] The logic of spectral analysis on the stiffness matrix of the high-pile wharf in the healthy and undamaged state is as follows:

[0081] The healthy and undamaged state refers to the stable working state of the target steel pipe pile high-pile wharf after completion and initial service period. The determination of this state needs to be combined with the structure characteristics, environmental conditions and monitoring data for comprehensive judgment. The period from the 6th month to the 18th month after the completion of the wharf is usually selected as the reference establishment period of the healthy and undamaged state. This selection is based on the following engineering considerations: the structure has completed the initial settlement and deformation, the concrete material has fully hardened and reached the design strength, the stress redistribution of the steel structure connection parts tends to be stable, and the structure has been tested by different seasonal environmental loads.

[0082] Spectral decomposition is performed on the stiffness matrix to obtain a set of standard orthogonal basis vectors and eigenvalues corresponding to each standard orthogonal basis vector. The eigenvalues are scalar weights, which are arranged in descending order to form the eigenvalue sequence as the reference spectrum. The set of standard orthogonal basis vectors is defined as the reference vector space.

[0083] Spectral analysis is a core mathematical tool in structural dynamics, its essence is to decompose a complex structural system into a series of independent vibration modes. For a complex engineering structure such as a steel pipe pile high-pile wharf, the overall stiffness matrix contains the stiffness distribution information of the structure in all directions in space. Through spectral analysis, this huge matrix system is decomposed into basic components that are easier to understand and analyze.

[0084] First, the complete stiffness matrix of the structure in the healthy undamaged state needs to be obtained. This matrix is established through finite element analysis and contains the integrated results of the stiffness contribution of all elements. The spectral analysis process starts with solving the eigenvalue problem, which is a standard mathematical calculation process aimed at finding a special scalar solution that makes the product of the stiffness matrix and the eigenvector equal to the product of the eigenvalue and the eigenvector.

[0085] The physical meaning of the eigenvalues is very clear. They represent the ratio of stiffness to equivalent mass of the structure in each independent vibration mode. Larger eigenvalues correspond to the main load-carrying paths and key stiffness contribution modes of the structure, while smaller eigenvalues reflect secondary or local stiffness characteristics. In the healthy state, these eigenvalues show a specific distribution pattern, reflecting the inherent stiffness characteristics of the structure.

[0086] The eigenvectors corresponding to each eigenvalue describe the deformation pattern of the structure in that specific vibration mode. These eigenvectors are orthogonal in mathematics, meaning that different vibration modes are independent of each other and do not couple energy. By standardizing these eigenvectors, a set of standard orthogonal basis vectors is obtained, which form a complete coordinate system to describe the deformation state of the structure.

[0087] The eigenvalues are arranged in descending order of numerical value to form an ordered eigenvalue sequence, which is defined as the reference spectrum. The importance of the reference spectrum lies in its systematic recording of the relative importance of each vibration mode of the structure in the healthy state. The eigenvalues at the top correspond to the main stiffness contribution modes of the structure, which are usually related to the overall bending, torsion, and other macroscopic deformations of the structure.

[0088] At the same time, the standardized eigenvectors form the reference vector space. Each basis vector in this space represents a basic deformation mode of the structure, from overall rigid body displacement to local subtle deformation, covering all possible deformation states of the structure. The establishment of the reference vector space provides a reference for subsequent damage identification. Any change in the state of the structure will be reflected in the changes of these basis vectors.

[0089] The establishment of a baseline spectrum can quantitatively assess the distribution characteristics of structural stiffness, while the baseline vector space provides the mathematical basis for describing the deformation state of the structure. When a structure is damaged, its stiffness characteristics will change, and this change will be directly reflected in the changes of eigenvalues ​​and eigenvectors. By comparing the difference between the current state and the healthy baseline state, the occurrence of damage can be accurately identified, and the location of the damage can be further located. This damage identification method based on spectrum analysis has high sensitivity and can detect early damage that is difficult to detect by traditional methods.

[0090] Step 3: Perform the same spectral analysis on the stiffness matrix of the target steel pipe pile high pile wharf to obtain the current spectrum and the current vector space. By calculating the distance between the current spectrum and the reference spectrum in a probabilistic statistical sense, a global damage index is generated.

[0091] The global damage index is calculated using a spectrum-based probability distribution divergence metric, specifically including:

[0092] Define the reference spectrum as and define the current spectrum as , Indicates the current moment. It is the transpose symbol;

[0093] The baseline spectrum is the sequence of eigenvalues ​​of the structure in a healthy state, and the current spectrum is the sequence of eigenvalues ​​measured at the current time t. These eigenvalues ​​represent the stiffness contribution of the structure in different modes. The discrete eigenvalue sequences are organized into ordered mathematical vectors to facilitate subsequent probability and statistical operations. The transpose symbol is explicitly represented in column vector form, which conforms to the linear algebra operation norm and ensures the dimensionality consistency of subsequent matrix and vector operations.

[0094] The eigenvalue sequences of the baseline spectrum and the current spectrum are normalized into probability distributions, and the probability distributions of the baseline spectrum and the current spectrum are calculated using the following formulas:

[0095] ;

[0096] in, To prevent division by zero constant, , These represent the order of the reference spectrum at position [number]. The scalar weight of the current position, and its ranking in the current spectrum. scalar weights of bits This represents the sorting order of the scalar weights in the eigenvalue sequence, and , The total number of eigenvalues ​​in the eigenvalue sequence. and They are respectively ranked in the reference spectrum at the 1st The scalar weighted normalized probability value of the current position, and the position ranked in the current spectrum. The scalar weighted normalized probability value of the bit;

[0097] and It reflects the relative importance of each scalar weight in the overall spectrum, transforming absolute stiffness eigenvalues ​​into relative weight probability values. The larger the value, the higher the ranking in terms of health status. The greater the contribution of the vibration mode corresponding to the scalar weight of the position, the greater its contribution to the overall stiffness. The larger the value, the higher the ranking at the current time. The vibration modes corresponding to the scalar weights of the bits remain important in real-time structures;

[0098] When a certain Compared to When the probability distribution decreases significantly, it indicates a reduction in the stiffness contribution of the corresponding vibration mode, suggesting damage in the relevant region of that mode. When the overall shape of the probability distribution changes, it reflects a change in the stiffness distribution characteristics of the structure. or The larger the value, the more corresponding or The larger the value, the stronger the positive correlation. The sum of all probability values ​​is 1, ensuring the formation of a complete probability distribution.

[0099] Transform the sequence of eigenvalues ​​into a probability distribution such that the proportion of each eigenvalue in the sum of all eigenvalues ​​is used as its probability.

[0100] Calculate the intermediate distribution The global damage exponent at the current time step is calculated using the Jensen-Shannon divergence:

[0101] ;

[0102] in, The global damage index at the current moment has a range of values. The larger the value, the higher the degree of damage, and the base of the logarithm is 2. , To avoid a pre-defined constant with a denominator of 0;

[0103] The intermediate distribution serves as the benchmark distribution for Jensen-Shannon divergence calculation, providing a reference point for measuring probability differences. It establishes a compromise reference system between the health state and the current state, ensuring the symmetry and fairness of damage assessment, avoiding assessment bias caused by using any single state as the benchmark alone, and improving the reliability of damage identification.

[0104] It reflects the overall degree of difference between the baseline spectrum and the current spectrum in terms of probability distribution, and its quantitative structure reflects the overall degree to which the current state deviates from the healthy state. A value close to 0 indicates that the probability distribution of the current spectrum is highly similar to that of the baseline spectrum, and the structure is in a healthy state. A gradually increasing value indicates that the stiffness characteristics of the structure are undergoing a systematic change. A value close to 1 indicates that the structure has suffered severe overall damage;

[0105] A sustained, slow increase indicates accumulated structural damage or material degradation. A sudden, rapid increase indicates that the structure has suffered sudden damage or localized destruction. The fluctuations at different times reflect the temporal variability of the structural state; when and The greater the difference, the larger the absolute value of the corresponding logarithmic term. The value increases accordingly, when all i correspond to and When the differences are small, the logarithmic terms tend to be close to 0. The value approaches 0; Ensure that the calculation remains stable when the probability value is 0;

[0106] Preventing zero constant Choose a positive real number much smaller than the smallest eigenvalue; usually, the average of the eigenvalues ​​is used. The magnitude ensures stable computation even in special cases where the sum of eigenvalues ​​is extremely small; it also prevents constants with zero denominators. Choose a sufficiently small positive real number, usually taking... The order of magnitude is such that, while ensuring computational stability, the impact on the original probability distribution is minimized as much as possible.

[0107] The specific data for some time numbers and advantage estimates are shown in Table 1.

[0108] Table 1 Global Damage Index:

[0109]

[0110] Through data analysis, it was observed that there are certain correlations between different characteristic parameters. For example, it can be seen from the data that there is a clear correlation between the current probability value and the global damage index. As the monitoring time progresses, the current probability value shows fluctuating changes, while the global damage index shows a complex response accordingly.

[0111] In the analysis of the relationship between the current probability value and the global damage index, the global damage index tends to increase when the current probability value deviates from the baseline probability value, for example, at time number 2, the current probability value is 0.162, which is slightly higher than the baseline value, and the global damage index is 0.0158; while at time number 3, the current probability value decreases to 0.135, and the global damage index further increases to 0.0253, which indicates that the current probability value deviating from the baseline value in either direction may lead to changes in the structure state, thereby affecting the size of the global damage index;

[0112] Further observation of the relationship between the intermediate distribution and the global damage index shows that when the intermediate distribution value is small, the corresponding global damage index is often large, for example, at time number 9, the intermediate distribution value is 0.13, and the global damage index reaches 0.0715; while at time number 14, the intermediate distribution value further decreases to 0.12, and the global damage index increases to 0.1514, which is due to the fact that the intermediate distribution reflects the degree of deviation of the structure state, and a larger deviation will lead to a significant increase in the damage index;

[0113] From the overall trend, there is a complex nonlinear relationship between the change pattern of the current probability value and the response of the global damage index, for example, during time number 6 to time number 8, the current probability value first decreases and then increases, while the global damage index first increases and then decreases, which shows that the change of the structure state will affect the final damage assessment result through the comprehensive action of multiple parameters, and the interaction of various parameters needs to be considered comprehensively in engineering monitoring to accurately assess the health status of the structure.

[0114] Step 4: If the global damage index exceeds the preset threshold, it is determined that damage has occurred, the deviation degree of each standard orthogonal basis vector in the current vector space and the corresponding standard orthogonal basis vector in the baseline vector space is calculated through projection operation, and the standard orthogonal basis vector with abnormally high deviation degree is inversely mapped back to its corresponding physical space coordinate, thereby realizing accurate positioning of the damage location;

[0115] The guarantee criterion value of the standard orthogonal basis vector corresponding to the i-th scalar weight of the current spectrum is calculated

[0116]

[0117] wherein, is the standard orthogonal basis vector corresponding to the i-th scalar weight of the baseline spectrum in the baseline vector space, is the standard orthogonal basis vector corresponding to the i-th scalar weight of the current spectrum in the current vector space, represents the inner product of the vector, and the absolute value is used to eliminate the sign uncertainty, represents the L2 norm;​​

[0118] Reflects the similarity degree of the standard orthogonal basis vector corresponding to the i-th scalar weight in the healthy state and the current state in the direction, quantifies the angle relationship of the two vectors in space, and is 1 when the directions are completely the same and 0 when the directions are completely orthogonal; a value close to 1 indicates that the standard orthogonal basis vector in the current state is highly consistent with the health benchmark, and the corresponding vibration mode has not changed significantly, a value significantly less than 1 indicates that the direction of the standard orthogonal basis vector has changed, and the corresponding structural vibration characteristics are abnormal;

[0119] When the structure is locally damaged, the standard orthogonal basis vector of the affected area will be deflected in direction, and the more serious the damage, the greater the change in the direction of the corresponding standard orthogonal basis vector, the smaller the value, the greater the change in the direction of the standard orthogonal basis vector corresponding to the different ordering position i, The change pattern can reflect the type and location characteristics of the damage; the greater the inner product value of the two vectors, the greater the value, and the two vectors are positively correlated, and the product of the vector norms is used as a normalization factor to ensure that the result is in the range of 0 to 1, and the absolute value operation eliminates the influence of the uncertainty of the direction symbol of the vector;

[0120] Define the deviation degree of the standard orthogonal basis vector corresponding to the i-th scalar weight of the current spectrum as: where ;

[0121] Directly quantifies the direction change degree of the standard orthogonal basis vector corresponding to the i-th scalar weight, converts the similarity measure into a difference measure, and facilitates damage sensitivity analysis; a value close to 0 indicates that the direction of the standard orthogonal basis vector has not changed significantly, and the corresponding structural region is intact, a value significantly greater than 0 indicates that the direction of the standard orthogonal basis vector has been significantly deflected, indicating that the corresponding structural region is damaged, a value close to 1 indicates that the direction of the standard orthogonal basis vector has changed fundamentally, and the corresponding is a serious damage;

[0122] The value of different ordering positions i has a clear physical meaning, and the increase of the of a low ordering position (i is smaller) usually reflects the degradation of overall stiffness, and the increase of the of a high ordering position (i is larger) usually reflects a local damage, and a sudden increase in the of a specific ordering position indicates a damage in the sensitive region of the corresponding mode; the smaller the value, The larger the value, the stronger the negative correlation. This linear transformation ensures the monotonicity and consistency of damage sensitivity.

[0123] Using the pre-calibrated unit sensitivity matrix Calculate the positioning score of each unit j at the current time. Its formula is:

[0124] ;

[0125] in, For the orthogonal basis vectors sorted at position i, the first one is the first one. The projection coefficients of each element are obtained by performing finite element analysis on each orthogonal basis vector in the reference vector space under healthy and undamaged conditions. The absolute value is used to eliminate the projection sign cancellation effect, and j is the index of the element in the target steel pipe pile high pile wharf.

[0126] It comprehensively reflects the weighted contribution of the j-th unit to the deviation of all orthogonal basis vectors, and quantifies the degree of participation of each unit in the overall damage mode; The higher the value, the more involved the element is in all vibration modes, and the greater the likelihood of damage. A value close to 0 indicates that the element remains essentially unchanged across various vibration modes and is in good working order. The spatial distribution pattern can visually display the concentrated areas of damage;

[0127] Damaged elements typically exhibit abnormalities in multiple vibration modes, resulting in a significant increase in their localization scores. The spatial gradient variation of localization scores can help determine the damage boundary, and the relative magnitude of localization scores among different elements can assess the distribution of damage severity. The larger the value, the better. The greater the contribution, the stronger the positive correlation. The larger the value, the higher the sensitivity of the j-th unit to the i-th orthonormal basis vector. The greater the impact of the deviation of this vector on the unit score, the absolute value operation ensures that the contribution of each orthonormal basis vector is positive and avoids mutual cancellation.

[0128] The projection coefficients of the orthogonal basis vector ranked at position i onto the element j are obtained by performing finite element analysis on each orthogonal basis vector in the reference vector space under healthy and non-destructive conditions. Each orthogonal basis vector describes a basic vibration mode of the structure, which is represented as a nodal displacement mode in the finite element model. For each orthogonal basis vector, its displacement components at relevant nodes of each element are extracted, and the sensitivity coefficient of the vector to each element is obtained by weighted averaging. The greater the value, the more obvious the vibration mode described by the i-th standard orthogonal basis vector is at the j-th unit. Once the matrix is established in the healthy state, it can be used as a reference frame for damage location;

[0129] The positioning score The unit with the highest value is determined as the damage location. Combined with the node coordinates of the unit and the geographical mapping relationship of the actual structure, damage location is achieved.

[0130] The positioning score The positioning score is a quantitative index calculated by integrating the deviation degree information of all standard orthogonal basis vectors. This score reflects the abnormality of the j-th unit at the current time relative to the healthy state. The calculation of the score is based on the pre-calibrated sensitivity matrix S, which establishes the correspondence between the standard orthogonal basis vectors and the structure units. The elements of the sensitivity matrix characterize the response strength of the i-th standard orthogonal basis vector corresponding to the vibration mode at the j-th unit, which essentially reflects the sensitivity of different vibration modes to each structure unit;

[0131] The unit with the highest positioning score is determined as the damage location. This judgment is based on the basic principles of structural dynamics: when a structure is locally damaged, the stiffness characteristics of the damaged area will change, which will affect all vibration modes passing through the area. Different vibration modes have different sensitivities to the same damage. The positioning score integrates the abnormal information of all vibration modes through weighted summation, so it can accurately identify the unit most likely to be damaged;

[0132] Suppose there is a crack in the pile body of the 15th pile in a steel pipe pile wharf. During dynamic testing, this crack will cause significant shape changes in the vibration modes near the crack location. By calculating the positioning score of each unit, it is found that the score of the unit corresponding to the 15th pile at the corresponding position is significantly higher than that of other units, thus locking the damage location;

[0133] Mapping the node coordinates of the unit to the geographical position of the actual structure is a key step for damage location from mathematical space to physical space, including the following levels: First, during the finite element modeling stage, the correspondence between the model coordinate system and the actual engineering coordinate system needs to be established. The node coordinates of each unit not only contain its relative position in the model, but also contain its absolute position in the global coordinate system. For a steel pipe pile wharf, this usually includes longitude, latitude, and elevation information in the geodetic coordinate system. Second, the correspondence between the unit and the specific structure member needs to be established, such as which section of which beam does a beam unit correspond to, and which part of which panel area does a shell unit correspond to. This correspondence needs to be clearly recorded during the modeling stage to form a complete unit-member mapping table.

[0134] The determination of damage occurrence also includes a confirmation process in the time domain, i.e. the global damage index is compared with a threshold value The global damage index is filtered by exponential weighted moving average to obtain the smoothed global damage index:

[0135] ;

[0136] wherein, is the smoothed global damage index, is the global damage index, is the smoothed global damage index at time t, is the forgetting factor, is the sampling interval;

[0137] The smoothed global damage index reflects the trend of the global damage index and filters out random fluctuation disturbance, which provides a smoothed observation sequence of the structural state evolution, a continuous rise indicates that the structural damage is accumulating and developing, a stable state indicates that the structure is relatively stable, a sudden jump indicates that the structure has suffered a sudden damage;

[0138] The larger the value is, the higher the weight of historical data is, the change is more gentle, the smaller the value is, the higher the weight of current data is, the more sensitive to immediate changes, when the value increases, the corresponding value increases, but the change rate is controlled by ; , , ;

[0139] For the lower limit , a too small value will result in insufficient filtering effect and cannot effectively smooth the random fluctuations, and it is necessary to ensure that sufficient historical information is retained, , a too large value will result in a too slow response of the system to the real damage, and it is necessary to ensure that new monitoring data can timely affect the filtering result, and a too large value will make the filtering result have too strong inertia and be difficult to reflect the rapid changes of the state;

[0140] is the time interval between two consecutive monitoring analyses, wherein , for the lower limit As a large-scale civil engineering structure, the dynamic response and damage development of steel pipe pile high pile wharf have a long time constant. Excessively high sampling frequency cannot provide additional effective information. Spectral analysis and damage index calculation require considerable computing resources. Reasonable intervals avoid unnecessary computational load. Too short sampling intervals will lead to high correlation between adjacent samples, reducing the effectiveness of information. Appropriate time intervals help to smooth the impact of short-term environmental fluctuations such as wind, waves, and traffic loads.

[0141] For the upper limit This ensures that significant structural changes throughout the day can be captured, and the 24-hour cycle covers environmental influences such as diurnal temperature variations and tidal changes, conforming to the standard operating cycle for engineering monitoring; for steel pipe pile high-pile wharves, Set between 1 hour and 6 hours;

[0142] when A damage alarm is triggered when the number of consecutive samplings exceeding a preset threshold reaches N, where N is a preset positive integer greater than 1; N and The alarm response time was jointly determined as follows ; ,in , For the lower limit A single exceedance is due to measurement noise or transient interference; two consecutive exceedances improve reliability, especially for the upper limit. To avoid delaying important alarms due to excessive consecutive over-limit requests;

[0143] By continuously exceeding limits, the reliability and anti-interference capability of the alarm are ensured. The value of N is determined comprehensively based on the importance of the project, the level of environmental noise, and the sampling frequency. A circular buffer is established to record the N most recent sampling times. Value, used to determine continuous exceedance situations in real time;

[0144] The logic for obtaining the preset threshold is as follows: multiple measurements are taken on the target steel pipe pile high pile wharf in a healthy and undamaged state to obtain a series of historical data of global damage index to form a historical dataset. The mean and standard deviation of the historical dataset are calculated, and the mean plus three times the standard deviation is used as the preset threshold.

[0145] Based on the assumption of normal distribution, the threshold of mean plus three standard deviations corresponds to a confidence level of 99.73%, ensuring that the probability of false alarms is less than 0.27% in a healthy state, while maintaining sensitivity to actual damage. The threshold is set based on actual measurement data to avoid the influence of subjective experience. Statistical methods ensure the objectivity and reliability of the threshold setting, and the three standard deviation criterion achieves a good balance between sensitivity and reliability.

[0146] Please see Figure 6The application further provides a steel pipe pile high-pile wharf damage determination system, which is used for executing the steel pipe pile high-pile wharf damage determination method and comprises the following modules.

[0147] A matrix construction module is configured to construct an abstract mathematical object representing overall mechanical characteristics of the target steel pipe pile high-pile wharf according to current data parameters of the target steel pipe pile high-pile wharf, the abstract mathematical object being a stiffness matrix, which is determined based on current data parameters of each unit of the wharf, i.e., determined by mapping relationships of geometric topology, material constants and boundary constraint conditions of the high-pile wharf structure.

[0148] A data analysis module is configured to perform spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf in a healthy and undamaged state, to decompose the stiffness matrix into a group of standard orthogonal basis vectors and corresponding scalar weights, to arrange all the scalar weights in order and define as a reference spectrum, and to compose a reference vector space with the group of standard orthogonal basis vectors.

[0149] A damage calculation module is configured to perform the same spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf, to obtain a current spectrum and a current vector space, to generate a global damage index by calculating a distance between the current spectrum and the reference spectrum in the sense of probability statistics.

[0150] A position determination module is configured to determine that damage occurs if the global damage index exceeds a preset threshold, to calculate deviation degrees of each standard orthogonal basis vector in the current vector space and a corresponding standard orthogonal basis vector in the reference vector space by projection operation, to calculate a positioning score of each unit based on the deviation degrees of all the standard orthogonal basis vectors, and to determine a physical space coordinate corresponding to a unit with the highest positioning score as a damage position, so as to realize accurate positioning.

[0151] The above formulas are all dimensionless numerical calculations, the formulas are obtained by collecting a large amount of data to simulate a formula of the nearest real situation, and the preset parameters in the formulas are set by a person skilled in the art according to actual conditions.

[0152] The above embodiments can be realized by software, hardware, firmware or any combination thereof, in whole or in part. When realized by software, the above embodiments can be realized in the form of a computer program product in whole or in part. A person skilled in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized by hardware or software methods depends on specific application and design constraints of the technical solutions.

[0153] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, and may be located in one place, or distributed on multiple network units. Part or all of the units can be selected to achieve the purpose of the embodiment of the present application according to actual needs.

[0154] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for determining damage of a steel pipe pile high-pile wharf, characterized by, The specific steps include: Step 1: According to the current data parameters of the target steel pipe pile high-pile wharf, an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high-pile wharf is constructed, which is a stiffness matrix based on the current data parameters of each unit of the wharf, i.e. the geometric topology, material constants and boundary constraint conditions of the high-pile wharf structure are confirmed through a mapping relationship; Step 2: The stiffness matrix of the target steel pipe pile high-pile wharf in a healthy and undamaged state is subjected to spectral analysis to decompose it into a set of standard orthogonal basis vectors and their corresponding scalar weights. All scalar weights are arranged in order and defined as a reference spectrum, and the set of standard orthogonal basis vectors form a reference vector space; Step 3: The stiffness matrix of the target steel pipe pile high-pile wharf is subjected to the same spectral analysis to obtain the current spectrum and the current vector space. The global damage index is generated by calculating the distance between the current spectrum and the reference spectrum in the sense of probability statistics; Step 4: If the global damage index exceeds the preset threshold, it is determined that damage has occurred. The deviation degree of each standard orthogonal basis vector in the current vector space from the corresponding standard orthogonal basis vector in the reference vector space is calculated by projection operation. The positioning score of each unit is calculated based on the deviation degrees of all standard orthogonal basis vectors. The physical space coordinates corresponding to the unit with the highest positioning score are determined as the damage location, thereby achieving accurate positioning.

2. The damage determination method for a steel pipe pile high-pile wharf according to claim 1, characterized by: The logic for constructing an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high-pile wharf based on its data parameters is as follows: The entire steel pipe pile high-pile wharf structure is discretized into multiple finite element model units, including pile units for simulating steel pipe piles, beam units for simulating cross beams, and plate units for simulating faceplates; The data parameters include the geometric topology, material constants and boundary constraint conditions of all units in the target steel pipe pile high-pile wharf. The geometric topology includes geometric dimensions and spatial layout distances, which are defined by node coordinates and unit connection relationships in the finite element model units. The material constants include elastic modulus and Poisson's ratio. The boundary constraint conditions simulate the pile-soil interaction by setting the equivalent spring stiffness of the pile bottom soil; Based on the geometric dimensions and material constants of each unit, the unit stiffness matrix is calculated according to the principles of structural mechanics. For pile units, the geometric dimensions are pile length, diameter and wall thickness. For beam and plate units, the geometric dimensions are their cross-sectional dimensions; According to the connection relationship between node coordinates and units, the stiffness matrices of all units are assembled into the initial overall stiffness matrix of the steel pipe pile high-pile wharf structure. The initial overall stiffness matrix is subjected to boundary condition processing to eliminate rigid displacement, and finally a symmetric positive definite stiffness matrix is generated.

3. The damage determination method of a steel pipe pile high-pile wharf according to claim 2, characterized by: The logic for spectral analysis of the stiffness matrix of the high-pile wharf in a healthy and undamaged state is as follows: Spectral decomposition of the stiffness matrix is performed to obtain a set of standard orthogonal basis vectors and corresponding eigenvalues, which are scalar weights. The eigenvalues are arranged in descending order to form an eigenvalue sequence as a reference spectrum. The set of standard orthogonal basis vectors is defined as a reference vector space.

4. The damage determination method of a steel pipe pile high-pile wharf according to claim 3, characterized by: The global damage index is calculated by using a spectral-based probability distribution divergence measure, and specifically includes: The reference spectrum is defined as and the current spectrum is defined as , denotes the current time, is the transpose symbol; The eigenvalue sequences of the reference spectrum and the current spectrum are normalized into probability distributions, wherein the probability distribution of the reference spectrum and the probability distribution of the current spectrum are calculated according to the following formulas: ； wherein, To prevent division by zero constant, , respectively represent the scalar weight ranked in the th position in the reference spectrum, the scalar weight ranked in the th position in the current spectrum, is the rank of the scalar weight in the eigenvalue sequence, and , is the total number of eigenvalues in the eigenvalue sequence, and respectively represent the normalized probability value of the scalar weight ranked in the th position in the reference spectrum, the normalized probability value of the scalar weight ranked in the th position in the current spectrum; Computing the intermediate distribution The global impairment index at the current time instant is computed using the Jensen-Shannon divergence: ； wherein, is the global damage index at the current time, whose value range is , and the greater the value, the higher the degree of damage, and the logarithm with base 2 makes , is a preset constant to avoid the denominator being 0.

5. The damage determination method of a steel pipe pile high-pile wharf according to claim 4, characterized by: Computing the guaranteed cost value of the standard orthogonal basis vector corresponding to the i-th bit scalar weight of the current spectrum : ； wherein, is the standard orthogonal basis vector in the reference vector space corresponding to the i-th scalar weight of the reference spectrum, is the standard orthogonal basis vector in the current vector space corresponding to the i-th scalar weight of the current spectrum, denotes the inner product of vectors, and the absolute value is used to eliminate the sign uncertainty, denotes the L2 norm; The deviation degree of the standard orthogonal basis vector corresponding to the i-th bit scalar weight of the current spectrum is defined as: wherein ; Utilizing a pre-calibrated cell sensitivity matrix , the positioning score of each cell j at the current time instant is calculated , the formula of which is: ； in, For the orthogonal basis vectors sorted at position i, the first one is the first one. The projection coefficient of each element, the absolute value of which is used to eliminate the projection sign cancellation effect, and j is the index of the element in the target steel pipe pile high pile wharf; The localization score is calculated The cell with the highest value is determined as the damage location, and the node coordinates of the cell are combined with the geographical mapping relationship of the actual structure to realize damage localization.

6. The damage determination method of a steel pipe pile high-pile wharf according to claim 5, characterized by: The determination of the occurrence of damage also includes a confirmation process in the time domain, that is, the determination of the occurrence of damage is confirmed by the following formula: The global damage index is filtered by exponential weighted moving average to obtain a smoothed global damage index: ； wherein, is the smoothed global impairment index, is the smoothed global impairment index, is the smoothed global impairment index at time t, is the forgetting factor, is the sampling interval; When When the number of samples exceeding the preset threshold consecutively reaches N times, an injury alarm is triggered, where N is a preset positive integer greater than 1.

7. The damage determination method of a steel pipe pile high-pile wharf according to claim 6, characterized by: The preset threshold is obtained by measuring the target steel pipe pile high-pile wharf in a healthy and undamaged state multiple times to obtain a series of historical data of the global damage index to form a historical data set, calculating the mean and standard deviation of the historical data set, and adding three times the standard deviation to the mean as the preset threshold.

8. A steel pipe pile high-pile wharf damage determination system characterized by comprising: a damage determination device; a damage determination program; and a damage determination database. The system is used to perform the steel pipe pile high-pile wharf damage determination method of any one of claims 1-7, comprising: A matrix construction module is configured to construct an abstract mathematical object representing the overall mechanical properties of the target steel pipe pile high-pile wharf according to the current data parameters of the target steel pipe pile high-pile wharf, wherein the abstract mathematical object is a stiffness matrix, which is based on the current data parameters of each unit of the wharf, i.e., the geometric topology, material constants, and boundary constraint conditions of the high-pile wharf structure are confirmed through a mapping relationship; A data analysis module is configured to perform spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf in a healthy and undamaged state to decompose it into a set of standard orthogonal basis vectors and their corresponding scalar weights, arrange all the scalar weights in order and define them as a reference spectrum, and form a reference vector space with the set of standard orthogonal basis vectors; A damage calculation module is configured to perform the same spectral analysis on the stiffness matrix of the target steel pipe pile high-pile wharf to obtain a current spectrum and a current vector space, and generate a global damage index by calculating the distance between the current spectrum and the reference spectrum in the sense of probability statistics; A location determination module is configured to determine that damage has occurred if the global damage index exceeds the preset threshold, calculate the deviation degree of each standard orthogonal basis vector in the current vector space from the corresponding standard orthogonal basis vector in the reference vector space through projection operation, calculate the positioning score of each unit based on the deviation degrees of all standard orthogonal basis vectors, and determine the physical space coordinates corresponding to the unit with the highest positioning score as the damage location, thereby achieving precise positioning.

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