Structural vibration monitoring and evaluating method for vibration source time-varying characteristics

Abstract

The invention relates to a structural vibration monitoring and evaluating method for vibration source time-varying characteristics. The method comprises the following steps: monitoring vibration of a vibration source of power equipment; reducing vibration of a vibration source of the power equipment and extracting dominant frequency characteristics of the vibration source; establishing a mapping relation between single vibration source excitation and structural global vibration response; determining structural global vibration responses under the action of all the power equipment vibration components; classifying vibration source vibration signal categories based on the power equipment vibration source vibration dominant frequency characteristics; superposing the structure global vibration response under the action of each power device, and obtaining a structure global vibration frequency value under the action of all the power devices; and evaluating the global micro-vibration level of the structure. The invention provides a theoretical method for evaluating the micro-vibration grade of an industrial upstairs internal precise instrument use environment in real time, and provides a technical implementation path for dynamic evaluation of the vibration influence of upstairs power equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial building structure health monitoring, and in particular to a structural vibration monitoring and evaluation method oriented towards time-varying vibration sources. Background Art

[0002] Industrial building structures house both precision instruments and power equipment. These instruments achieve micron- or even nanometer-level precision. The vertical structural vibrations induced by these equipment are a key factor affecting the micro-vibration level requirements for the operating environment of these instruments. Because the power equipment starts and stops randomly and their operating times are not completely synchronized, the internal vibration sources within industrial building structures exhibit time-varying characteristics. Therefore, dynamically assessing the micro-vibration levels of precision instruments operating under the influence of these time-varying vibration sources is a key issue.

[0003] Monitoring and evaluation can provide real-time understanding of structural vibration and over-limit warning, which is of great significance for ensuring the process accuracy of precision instruments. Existing monitoring and evaluation methods mainly obtain the micro-vibration level at the monitoring point through finite element simulation or actual vibration measurement in the vibration-sensitive area. However, the monitoring and evaluation method based on finite element numerical simulation involves the establishment of various refined models. Industrial buildings are large in scale and require high accuracy. The calculation is time-consuming and has high latency, and it is impossible to achieve synchronous update of vibration evaluation with dynamic adjustment of power equipment start and stop; the method based on actual vibration measurement in the vibration-sensitive area requires the deployment of monitoring points in advance. The time-varying nature of the vibration source of the power equipment will cause the area with greater vibration influence to change in real time, making it impossible to accurately deploy effective monitoring points. Summary of the Invention

[0004] In order to solve the problem that the existing technology is not suitable for time-varying vibration sources inside industrial building structures, the present invention provides a structural vibration monitoring and evaluation method oriented towards time-varying vibration sources, providing a technical implementation path for dynamically evaluating the vibration impact of power equipment inside industrial buildings.

[0005] According to a first aspect of an embodiment of the present invention, a method for monitoring and evaluating structural vibration based on time-varying vibration sources is provided, the method comprising:

[0006] Monitor and obtain relevant data of the preset power equipment vibration source; the relevant data includes: a vertical vibration acceleration time history data set of the power equipment, and a structural floor or ground vibration velocity amplitude data set excited by the power equipment;

[0007] Using the relevant data, the optimal number of layers is determined through a preset VMD decomposition to reduce the vibration of the power equipment source and extract its main frequency characteristics;

[0008] Establish a finite element model of the industrial building structure, arrange points, determine the vibration response of the points, and establish a mapping relationship between single vibration source excitation and the global vibration response of the structure;

[0009] Utilizing the mapping relationship between the single vibration source excitation and the global vibration response of the structure, the global vibration response of the structure under the action of each power device alone and each vibration component is calculated;

[0010] According to the main frequency characteristics of the vibration source of the power equipment, the vibration signal of the vibration source is divided into beat frequency P type, double frequency B type and Z type signal;

[0011] Based on the calculation results of the global vibration response of the structure under the action of each power device alone and each vibration component, as well as the results of the vibration signal division of the vibration source, the vibration components of the power device are regarded as simple harmonic vibrations. Considering the phase characteristics of different types of signals, the vibration superposition response is calculated through Monte Carlo simulation to obtain the global vibration frequency value of the structure;

[0012] The grid is divided with the layout point as the center, and the global micro-vibration level of the structure is evaluated according to the global vibration frequency value of the structure.

[0013] Furthermore, the method of utilizing the relevant data to reduce the vibration of the power equipment source and extracting its main frequency characteristics includes:

[0014] Perform K∈[2,8] VMD decomposition on the nth power station equipment signal to obtain the intrinsic modal components and calculate the spectrum kurtosis of each intrinsic modal component. The optimal number of decomposition layers is obtained by iteratively finding the maximum absolute difference between the minimum spectrum kurtosis of two adjacent layers.

[0015] Using the optimal decomposition layer number, VMD decomposition of the vibration signal of the n-th power equipment is performed.

[0016] Obtaining a preset number of natural modal components, their center frequencies and frequency amplitudes;

[0017] The natural mode component corresponding to the minimum spectrum kurtosis is classified as the environmental noise component, and the remaining natural mode components are classified as the power equipment vibration components;

[0018] Adding the vibration components of the power equipment to obtain a reconstructed signal after noise reduction;

[0019] The center frequency and frequency amplitude of the vibration component of the power equipment are regarded as the main frequency characteristics of the vibration signal of the current power equipment vibration source.

[0020] Furthermore, the establishment of a finite element model of the industrial building structure, the arrangement of points, the determination of point vibration responses, and the establishment of a mapping relationship between single vibration source excitation and global structural vibration response include:

[0021] Divide the standard floor slab of the preset finite element model into a rectangular grid, where odd-numbered points are located at the edge of the slab and even-numbered points are located at the mid-span of the slab;

[0022] Based on the rectangular grid, the center of the middle floor slab is used as the excitation point to obtain the three-dimensional distance and vibration velocity amplitude of each point;

[0023] The ratios of the vibration velocity amplitudes of all the points to the measured vibration velocity amplitudes of the structural floor induced by the power equipment selected in the finite element model are calculated respectively, and a mapping relationship between the single vibration source excitation and the global vibration response of the structure is established.

[0024] Furthermore, the mapping relationship between the single vibration source excitation and the global vibration response of the structure is used to calculate the global vibration response of the structure under the action of each power device alone and each vibration component, including:

[0025] Using the mapping relationship between the single vibration source excitation and the global vibration response of the structure, the global vibration velocity amplitude of the structure under the action of the nth power device alone is calculated using the following formula:

[0026]

[0027] in, Based on the mapping relationship between single vibration source excitation and global vibration response of the structure, μ x,y,z The vibration velocity amplitude and V at the point x, y, and z in the three directions of the distance from the nth power equipment are calculated using the linear interpolation algorithm. n The ratio of

[0028] Based on the calculation result of the global vibration velocity amplitude of the structure under the action of the nth power equipment alone, the global vibration velocity amplitude of the structure under the action of the tth power equipment vibration component of each nth power equipment is obtained by the following formula;

[0029]

[0030] Among them, A t is the component amplitude.

[0031] Furthermore, the vibration source vibration signal is divided into beat frequency P type, double frequency B type and Z type signals according to the main frequency characteristics of the vibration source of the power equipment, including:

[0032] Based on the main frequency characteristics of the vibration source of the power equipment, the vibration signal category of the vibration source is divided. If a group of power equipment vibration component signals with a frequency ratio of ξ∈[0.9,1.1] and an amplitude ratio of ψ∈[0.33,3] are classified as beat frequency P type signals;

[0033] If the frequency ratio ξ is an even number and the amplitude ratio ψ∈[0.9,1.1], a group of power equipment vibration component signals are classified as frequency-multiplied Class B signals;

[0034] Otherwise, the remaining power equipment vibration component signals are classified as Class Z signals.

[0035] Furthermore, the method further comprises:

[0036] If a group of power equipment vibration component signals meets the classification rules of both P-type signals and B-type signals, they will be classified as P-type signals first.

[0037] Furthermore, based on the calculation results of the global vibration response of the structure under the action of each power device alone and each vibration component, and the result of the vibration signal division of the vibration source, the vibration components of the power device are regarded as simple harmonic vibrations, and the phase characteristics of different types of signals are considered. The vibration superposition response is calculated through Monte Carlo simulation to obtain the global vibration frequency value of the structure, including:

[0038] Based on the calculation results of the global vibration response of the structure under the action of each power device alone and each vibration component, and the result of the division of the vibration signal of the vibration source, the vibration component of the power device is regarded as a simple harmonic vibration;

[0039] For P-type signals, the phase of each group of power equipment vibration component signals To satisfy [0,2πf p ] the same random number uniformly distributed; where f p The average vibration frequency of the vibration components of this group of power equipment;

[0040] For Class B signals, the phase of the low-frequency vibration signal in each group of power equipment vibration components To satisfy [0,2πf d ] Uniformly distributed different random numbers, where f d The vibration frequency of the low-frequency vibration signal in this group of power equipment vibration components, the phase of the high-frequency vibration signal corresponding to the low-frequency vibration signal ξ is the frequency ratio of the vibration components of this group of power equipment;

[0041] For Class Z signals, the signal phase of each power equipment vibration component Different random numbers that satisfy the uniform distribution between [0,2π];

[0042] Based on the phase characteristics of different types of signals, the vibration signal of a certain point of the structure under the action of multiple power equipment is obtained;

[0043] Based on the vibration signal at a certain point of the structure under the action of the multiple power equipment, the vibration superposition response is calculated based on Monte Carlo simulation, and the percentile value at which the cumulative probability reaches a threshold is taken as the frequency value.

[0044] Furthermore, the grid is divided with the deployment point as the center, and the global micro-vibration level of the structure is evaluated according to the global vibration frequency value of the structure, including:

[0045] Taking the layout point as the center of each grid, divide each floor of the industrial upper building structure into several rectangular grids;

[0046] If the vibration frequency value P at the point y ∈[0,30)μm / s, the vibration level of the grid area centered at this point is defined as Class A;

[0047] If the vibration frequency value P at the point y ∈[30,100)μm / s, the vibration level of the grid area centered at this point is defined as Class B;

[0048] If the vibration frequency value P at the point y ∈[100,1000)μm / s, the vibration level of the grid area centered at this point is defined as level C;

[0049] If the vibration frequency value P at the point y ∈[1000,+∞)μm / s, the vibration level of the grid area centered at this point is defined as level D;

[0050] The structural vibration of industrial buildings is evaluated based on the vibration frequency values ​​at all points.

[0051] The technical solutions provided by the embodiments of the present invention may have the following beneficial effects:

[0052] By real-time monitoring of vibration source excitation, the vibration velocity frequency value PY at all points in the entire structure is dynamically obtained, the dynamic division of micro-vibration levels at all points in the entire structure is realized, and the real-time micro-vibration level distribution of the precision instrument use environment is obtained.

[0053] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0055] Figure 1 This is a flow chart of a structural vibration monitoring and evaluation method oriented towards time-varying vibration sources according to an exemplary embodiment;

[0056] Figure 2 This is a flow chart of the structural vibration monitoring and assessment method oriented towards the time-varying vibration source;

[0057] Figure 3 This is a flow chart of the method for determining the optimal number of VMD decomposition layers based on spectral kurtosis;

[0058] Figure 4This is a flow chart of the method for noise reduction and main frequency feature extraction of vibration signals of power equipment vibration sources;

[0059] Figure 5 This is a schematic diagram of the arrangement of vibration points on the industrial upper floor structure;

[0060] Figure 6 It is a schematic diagram of the distribution of micro-vibration levels of industrial upper floor structures. DETAILED DESCRIPTION

[0061] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, like numbers in different figures represent like or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0062] Example 1

[0063] See also Figure 1 , Figure 1 The present invention is a flow chart of a structural vibration monitoring and assessment method for time-varying vibration sources according to an exemplary embodiment. The method includes:

[0064] S1. Monitor and obtain relevant data on the preset power equipment vibration source; the relevant data include: a vertical vibration acceleration time history data set of the power equipment, a structural floor or ground vibration velocity amplitude data set excited by the power equipment;

[0065] S2. Using the relevant data to determine the optimal number of layers by a preset VMD decomposition, noise reduction power equipment vibration source vibration and extract its main frequency characteristics;

[0066] S3. Build a finite element model of the industrial building structure, arrange points, determine the vibration response of each point, and establish a mapping relationship between single-source excitation and the global vibration response of the structure.

[0067] S4. Calculate the global vibration response of the structure under the action of each power device alone and each vibration component using the mapping relationship between the single vibration source excitation and the global vibration response of the structure;

[0068] S5. According to the main frequency characteristics of the vibration source of the power equipment, the vibration source vibration signal is divided into beat frequency P class, frequency multiplication class B class and Z class signal;

[0069] S6. Based on the calculation results of the global vibration response of the structure under the action of each power device individually and each vibration component, as well as the results of the vibration signal segmentation of the vibration source, the vibration components of the power devices are regarded as simple harmonic vibrations. Considering the phase characteristics of different types of signals, the vibration superposition response is calculated through Monte Carlo simulation to obtain the global vibration frequency value of the structure;

[0070] S7. Divide the grid around the deployment point, and evaluate the global micro-vibration level of the structure based on the global vibration frequency value of the structure.

[0071] For specific implementation, please refer to Figure 2 It should be understood that although Figure 2 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction for the execution of these steps, and these steps can be performed in other orders.

[0072] First, execute step S1: Place vibration acceleration sensors at the contact interface of the bottom support of each power equipment vibration source inside the industrial building, with the placement position limited to within a horizontal distance of 0.1m from the bottom support. Collect the vertical vibration acceleration of the power equipment in real time. During signal processing, eliminate DC offset or baseline drift to form a complete vertical vibration acceleration time history data set [X1(t), X2(t), …, X n (t)], where X n (t) is the vertical vibration acceleration time history of the nth power equipment.

[0073] Vibration velocity sensors are placed near the bottom support of each power equipment in the industrial building, within a horizontal distance of 0.5m from the support. Dynamic data is collected on the vertical vibration velocity of the structural floor or ground caused by the power equipment, and the vertical vibration velocity amplitude of the structural floor or ground is obtained. During the signal processing, DC bias or baseline drift must be eliminated to form a complete data set of the structural floor or ground vibration velocity amplitude caused by the power equipment [V1, V2, …, V n ], where V n is the vertical vibration velocity amplitude of the structure excited by the nth power equipment.

[0074] Next, step S2 is executed, including determining the optimal number of VMD decomposition layers, performing vibration noise reduction on the power equipment vibration source based on the VMD decomposition with the optimal number of decomposition layers, and extracting the main frequency characteristics of the vibration of the power equipment vibration source;

[0075] S21, the determination of the optimal number of VMD decomposition layers is specifically as follows:

[0076] Set the initial VMD decomposition layer K to 2, the number of iterations m to 0, and the initial minimum spectrum kurtosis Kurt m is 0;

[0077] The vibration signal X of the nth power equipment obtained by monitoring n (t) Perform K VMD decompositions to obtain K intrinsic modal components {imf1, imf2,…, imf K}, VMD calculation formula is:

[0078]

[0079] Perform FFT transformation on each intrinsic mode component to obtain its spectrum {FFT1, FFT2,…, FFT K}, calculate the kurtosis of each intrinsic modal component spectrum, the calculation formula is:

[0080]

[0081] Among them, Kurt[FFT K ] is the kurtosis of the Kth intrinsic modal component spectrum, x i is the amplitude at the i-th frequency, and x is the mean of the frequency amplitudes of the K-th natural mode component spectrum. The minimum kurtosis is obtained by comparison, which is the minimum spectrum kurtosis Kurt under the K-th VMD decomposition. m+1 , the calculation formula is: Kurt m+1 =min{Kurt[FFT1],Kurt[FFT2],…,Kurt[FFT K ]};

[0082] If K is less than 8, add the decomposition layer K and the number of iterations m, add the step size to 1, and repeat the above steps in S21; if K is equal to 8, establish the decomposition layer K and the minimum spectrum kurtosis Kurt m The corresponding relationship is calculated, and the absolute difference of the minimum spectrum kurtosis under the two adjacent decomposition layers is calculated. The maximum value of the absolute difference and the corresponding two adjacent decomposition layers are compared and obtained. The larger decomposition layer is regarded as the decomposition layer required for the spectrum kurtosis to mutate, that is, the optimal decomposition layer number K best ;

[0083] Replace the power equipment vibration signal and repeat the above steps in S21 until the optimal VMD decomposition layer number of all power equipment vibration source vibration signals is obtained. The flow of the method for determining the optimal VMD decomposition layer number based on spectrum kurtosis in S21 is as follows: Figure 3 shown.

[0084] S22, the VMD decomposition based on the optimal decomposition level to perform vibration noise reduction on the power equipment vibration source is specifically as follows:

[0085] Based on the optimal decomposition level Kbest The vibration signal X of the nth power equipment n VMD decomposition of (t) yields K best Intrinsic modal components and its center frequency and frequency amplitude

[0086] The component corresponding to the minimum spectrum kurtosis is classified as the ambient background noise component, and the remaining components are classified as the power equipment vibration component;

[0087] Add the vibration components of the power equipment to obtain a reconstructed signal after noise reduction;

[0088] The vibration signal of the power equipment is replaced, and the above step S22 is repeated until the reconstructed signal after the vibration noise reduction of all the power equipment vibration sources is obtained.

[0089] S23, the extraction of the main frequency characteristics of the vibration source of the power equipment is specifically as follows:

[0090] The center frequency and frequency amplitude of the vibration component of the power equipment are regarded as the vibration signal X of the vibration source of this equipment. n (t) dominant frequency characteristics;

[0091] Replace the power equipment vibration signal and repeat step S23 until the main frequency characteristics of the vibration signals of all power equipment vibration sources are obtained. The process of the power equipment vibration source vibration signal noise reduction and main frequency feature extraction method in steps S22 and S23 is as follows: Figure 4 shown.

[0092] Next, step S3 is executed, which includes the arrangement of points, determination of point vibration responses, and determination of the mapping relationship between the single vibration source excitation and the global vibration response of the structure;

[0093] S31. The arrangement of the points is specifically as follows:

[0094] The finite element model of the industrial upper floor structure is established. The floor slabs of each standard floor are grouped according to the number of structural bays in the depth direction. The groups are named X1 to Xs. Each group is distributed over the vibration points H1 to Hm, forming a rectangular grid of points. Each standard floor has a total of s×m points. Among them, all odd-numbered points are arranged at the edge of the plate (on the beam), and all even-numbered points are arranged in the middle of the plate span, such as Figure 5 shown.

[0095] S32, the determination of the point vibration response is specifically as follows:

[0096] The measured 10s vertical vibration acceleration time history of any power equipment vibration source is selected as the excitation and applied to the center of the floor of the middle floor of the industrial upper building structure finite element model. The X, Y, and Z distances of each point from the vibration source and the vibration velocity amplitude V of each point are obtained.x,y,z ;

[0097] The middle floor is the middle floor of all standard floors in the structure, that is, there are F standard floors. If F is an even number, the middle floor is the middle floor from the bottom up. If F is an odd number, the middle floor is the layer.

[0098] S33, the mapping relationship between the single vibration source excitation and the global vibration response of the structure is determined specifically as follows:

[0099] Calculate the vibration velocity amplitude V of all points separately x,y,z The ratio of the vibration velocity amplitude of the structural floor induced by the power equipment selected in the measured finite element model to μ is obtained. x,y,z .

[0100] Next, execute step S4: calculate the global vibration velocity amplitude of the structure under the action of the nth power equipment alone. in, Based on the mapping relationship between single vibration source excitation and global vibration response of the structure, μ x,y,z The vibration velocity amplitude and V at the point x, y, and z in the three directions of the distance from the nth power equipment are calculated using the linear interpolation algorithm. n The ratio of

[0101] According to the noise reduction results, the vibration of the power equipment source is composed of several power equipment vibration components. To further separate them, the vibration velocity amplitude of the entire structure under the action of the t-th power equipment vibration component of every n power equipment is calculated:

[0102]

[0103] By analogy, the global vibration response of the structure under the action of all vibration components of all power equipment is obtained.

[0104] Next, step S5 is executed: the main frequency ratio and the amplitude ratio corresponding to the main frequency among all the vibration components of the power equipment are calculated, and a group of power equipment vibration component signals with a frequency ratio ξ∈[0.9,1.1] and an amplitude ratio ψ∈[0.33,3] are classified as beat frequency P type signals; a group of power equipment vibration component signals with an even frequency ratio ξ∈[0.9,1.1] are classified as multiplication frequency B type signals, and the remaining power equipment vibration component signals are classified as Z type signals;

[0105] It should be noted that each group of power equipment vibration component signals has only one category. If a group of power equipment vibration component signals meets the classification rules of both Class P and Class B signals, it will be classified as Class P signal first.

[0106] Next, step S6 is executed: each power equipment vibration component is regarded as a simple harmonic vibration, and the simple harmonic vibration amplitude of the t-th power equipment vibration component of each n power equipment is Phase Considered as random numbers;

[0107] For P-type signals, the phase of each group of power equipment vibration component signals To satisfy [0,2πf p ]The same random number uniformly distributed, where f p The average vibration frequency of the vibration components of this group of power equipment;

[0108] For Class B signals, the phase of the low-frequency vibration signal in each group of power equipment vibration components To satisfy [0,2πf d ] Uniformly distributed different random numbers, where f d The vibration frequency of the low-frequency vibration signal in this group of power equipment vibration components, the phase of the high-frequency vibration signal corresponding to the low-frequency vibration signal ξ is the frequency ratio of the vibration components of this group of power equipment;

[0109] For Class Z signals, the signal phase of each power equipment vibration component Different random numbers that satisfy the uniform distribution between [0,2π];

[0110] Therefore, the vibration O(t) at a certain point of the structure under the action of multiple power equipment can be expressed as:

[0111]

[0112] Where a and b are the number of groups of P-type signals and B-type signals respectively, and c is the number of Z-type signals; is the vibration velocity amplitude at a certain point of the structure under the action of the first power equipment vibration component of the i-th group P-type signal, and the rest are similar;

[0113] The number of Monte Carlo simulation samples is 10 5 Second, the vibration superposition response O(t) of all points of the structure under the action of all dynamic equipment vibration components is calculated based on Monte Carlo simulation. x,y,z , calculate the probability density function of the vibration superposition response of all points, and integrate to obtain the probability distribution function F(O) of the vibration superposition response;

[0114] Define the quantile value corresponding to the cumulative probability of 90% on the probability distribution function as the frequency value, and calculate the vibration frequency value P of all points y .

[0115] Finally, step S6 is executed: each floor of the industrial upper building structure is divided into a number of rectangular grids with the layout point as the center of each grid;

[0116] If the vibration frequency value P at the point y ∈[0,30)μm / s, the vibration level of the grid area centered at this point is defined as Class A;

[0117] If the vibration frequency value P at the point y ∈[30,100)μm / s, the vibration level of the grid area centered at this point is defined as Class B;

[0118] If the vibration frequency value P at the point y ∈[100,1000)μm / s, the vibration level of the grid area centered at this point is defined as level C;

[0119] If the vibration frequency value P at the point y ∈[1000,+∞)μm / s, the vibration level of the grid area centered at this point is defined as level D;

[0120] The vibration of industrial building structures is evaluated based on the vibration frequency values ​​of all points, such as Figure 6 shown.

[0121] In specific implementation, this application focuses on a structural vibration monitoring and assessment method for time-varying vibration sources, and has significant value through multi-dimensional precise monitoring and analysis: from the monitoring dimension, multi-position sensor arrangement and signal processing, combined with VMD decomposition, accurately capture the vibration source and structural vibration characteristics, laying a solid data foundation for subsequent analysis; in modeling and calculation, finite element model construction and mapping relationship, component response calculation, clearly sort out the relationship between vibration source and structural response; signal classification and simulation link, classification by characteristics and Monte Carlo simulation, in line with reality to obtain global vibration frequency values; grade assessment realizes global refined control of structural vibration, adapts to scenarios such as industrial building, from local vibration source monitoring to global risk assessment, through all links, to provide a complete technical solution for precise assessment of structural micro-vibration, scientific protection and optimized design, to ensure structural safety and stable equipment operation.

[0122] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0123] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is at least two.

[0124] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0125] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0126] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0127] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0128] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0129] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0130] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A structural vibration monitoring and assessment method oriented to the time-varying nature of vibration sources, characterized in that: The method comprises: Monitor and obtain relevant data of the preset power equipment vibration source; the relevant data includes: a vertical vibration acceleration time history data set of the power equipment, and a structural floor or ground vibration velocity amplitude data set excited by the power equipment; Using the relevant data, the optimal number of layers is determined through a preset VMD decomposition to reduce the vibration of the power equipment source and extract its main frequency characteristics; Establish a finite element model of the industrial building structure, arrange points, determine the vibration response of the points, and establish a mapping relationship between single vibration source excitation and the global vibration response of the structure; Utilizing the mapping relationship between the single vibration source excitation and the global vibration response of the structure, the global vibration response of the structure under the action of each power device alone and each vibration component is calculated; According to the main frequency characteristics of the vibration source of the power equipment, the vibration signal of the vibration source is divided into beat frequency P type, double frequency B type and Z type signal; Based on the calculation results of the global vibration response of the structure under the action of each power device alone and each vibration component, as well as the results of the vibration signal division of the vibration source, the vibration components of the power device are regarded as simple harmonic vibrations. Considering the phase characteristics of different types of signals, the vibration superposition response is calculated through Monte Carlo simulation to obtain the global vibration frequency value of the structure; The grid is divided with the layout point as the center, and the global micro-vibration level of the structure is evaluated according to the global vibration frequency value of the structure.

2. The method according to claim 1, characterized in that The method of utilizing the relevant data to reduce the vibration of the power equipment source and extracting its main frequency characteristics includes: Perform K∈[2,8] VMD decomposition on the nth power station equipment signal to obtain the intrinsic modal components and calculate the spectrum kurtosis of each intrinsic modal component. The optimal number of decomposition layers is obtained by iteratively finding the maximum absolute difference between the minimum spectrum kurtosis of two adjacent layers. Using the optimal decomposition layer number, VMD decomposition of the vibration signal of the n-th power equipment is performed. Obtaining a preset number of natural modal components, their center frequencies and frequency amplitudes; The natural mode component corresponding to the minimum spectrum kurtosis is classified as the environmental noise component, and the remaining natural mode components are classified as the power equipment vibration components; Adding the vibration components of the power equipment to obtain a reconstructed signal after noise reduction; The center frequency and frequency amplitude of the vibration component of the power equipment are regarded as the main frequency characteristics of the vibration signal of the current power equipment vibration source.

3. The method according to claim 1, characterized in that The method of establishing a finite element model of an industrial building structure, arranging points, determining the vibration response of the points, and establishing a mapping relationship between single vibration source excitation and global vibration response of the structure includes: Divide the standard floor slab of the preset finite element model into a rectangular grid, where odd-numbered points are located at the edge of the slab and even-numbered points are located at the mid-span of the slab; Based on the rectangular grid, the center of the middle floor slab is used as the excitation point to obtain the three-dimensional distance and vibration velocity amplitude of each point; The ratios of the vibration velocity amplitudes of all the points to the measured vibration velocity amplitudes of the structural floor induced by the power equipment selected in the finite element model are calculated respectively, and a mapping relationship between the single vibration source excitation and the global vibration response of the structure is established.

4. The method according to claim 1, wherein The method of calculating the global vibration response of the structure under the action of each power device alone and each vibration component by using the mapping relationship between the single vibration source excitation and the global vibration response of the structure includes: Using the mapping relationship between the single vibration source excitation and the global vibration response of the structure, the global vibration velocity amplitude of the structure under the action of the nth power device alone is calculated using the following formula: in, Based on the mapping relationship between single vibration source excitation and global vibration response of the structure, μ x,y,z The vibration velocity amplitude and V at the point x, y, and z in the three directions of the distance from the nth power equipment are calculated using the linear interpolation algorithm. n The ratio of Based on the calculation result of the global vibration velocity amplitude of the structure under the action of the nth power equipment alone, the global vibration velocity amplitude of the structure under the action of the tth power equipment vibration component of each nth power equipment is obtained by the following formula; Among them, A t is the component amplitude.

5. The method according to claim 1, wherein According to the main frequency characteristics of the vibration source of the power equipment, the vibration signal of the vibration source is divided into beat frequency P type, double frequency B type and Z type signals, including: Based on the main frequency characteristics of the vibration source of the power equipment, the vibration signal category of the vibration source is divided. If a group of power equipment vibration component signals with a frequency ratio of ξ∈[0.9,1.1] and an amplitude ratio of ψ∈[0.33,3] are classified as beat frequency P type signals; If the frequency ratio ξ is an even number and the amplitude ratio ψ∈[0.9,1.1], a group of power equipment vibration component signals are classified as frequency-multiplied Class B signals; Otherwise, the remaining power equipment vibration component signals are classified as Class Z signals.

6. The method according to claim 5, characterized in that The method further comprises: If a group of power equipment vibration component signals meets the classification rules of both P-type signals and B-type signals, they will be classified as P-type signals first.

7. The method according to claim 1, characterized in that The calculation results of the global vibration response of the structure under the action of each power device alone and each vibration component, as well as the result of the division of the vibration signal of the vibration source, regard the vibration component of the power device as a simple harmonic vibration, consider the phase characteristics of different types of signals, calculate the vibration superposition response through Monte Carlo simulation, and obtain the global vibration frequency value of the structure, including: Based on the calculation results of the global vibration response of the structure under the action of each power device alone and each vibration component, and the result of the division of the vibration signal of the vibration source, the vibration component of the power device is regarded as a simple harmonic vibration; For P-type signals, the phase of each group of power equipment vibration component signals To satisfy [0,2πf p ] the same random number uniformly distributed; where f p The average vibration frequency of the vibration components of this group of power equipment; For Class B signals, the phase of the low-frequency vibration signal in each group of power equipment vibration components To satisfy [0,2πf d ] Uniformly distributed different random numbers, where f d The vibration frequency of the low-frequency vibration signal in this group of power equipment vibration components, the phase of the high-frequency vibration signal corresponding to the low-frequency vibration signal ξ is the frequency ratio of the vibration components of this group of power equipment; For Class Z signals, the signal phase of each power equipment vibration component Different random numbers that satisfy the uniform distribution between [0,2π]; Based on the phase characteristics of different types of signals, the vibration signal of a certain point of the structure under the action of multiple power equipment is obtained; Based on the vibration signal at a certain point of the structure under the action of the multiple power equipment, the vibration superposition response is calculated based on Monte Carlo simulation, and the percentile value at which the cumulative probability reaches a threshold is taken as the frequency value.

8. The method according to claim 1, characterized in that The grid is divided with the deployment point as the center, and the global micro-vibration level of the structure is evaluated according to the global vibration frequency value of the structure, including: Taking the layout point as the center of each grid, divide each floor of the industrial upper building structure into several rectangular grids; If the vibration frequency value P at the point y ∈[0,30)μm / s, the vibration level of the grid area centered at this point is defined as Class A; If the vibration frequency value P at the point y ∈[30,100)μm / s, the vibration level of the grid area centered at this point is defined as Class B; If the vibration frequency value P at the point y ∈[100,1000)μm / s, the vibration level of the grid area centered at this point is defined as level C; If the vibration frequency value P at the point y ∈[1000,+∞)μm / s, the vibration level of the grid area centered at this point is defined as level D; Evaluate the structural vibration of industrial buildings based on the vibration frequency values ​​at all points.

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