Nuclear power station containment structure earthquake vulnerability analysis method based on multi-evaluation index fusion

Abstract

The invention discloses a nuclear power station containment structure earthquake vulnerability analysis method based on multi-evaluation index fusion, and the method comprises the steps: defining a generalized damage index of multi-evaluation index fusion, selecting a multi-element sub-damage index, carrying out the standardization and normalization processing of the multi-element sub-damage index, and obtaining the seismic vulnerability of a nuclear power station containment structure. Obtaining a novel structure damage index fused with multiple evaluation indexes; establishing a nuclear power station containment finite element model, performing incremental dynamic analysis on the nuclear power station containment structure, and extracting damage parameters; and performing multi-evaluation index comprehensive damage index calculation based on the overall damage index of the structure and the extracted damage parameters, and completing vulnerability analysis and earthquake vulnerability curve construction. According to the method, multiple evaluation indexes are fused, a novel structure damage index suitable for multiple scenes is provided, and the limitation that a traditional single index cannot balance brittle failure, accumulated damage and local failure is broken through. And the earthquake vulnerability analysis method for the containment structure of the nuclear power station is provided by applying the index, and good applicability is shown.

Description

Technical Field

[0001] The present invention relates to the technical field of civil engineering, and in particular to a seismic vulnerability analysis method for a nuclear power plant containment structure based on the fusion of multiple evaluation indicators. Background Art

[0002] The containment vessel of a nuclear power plant is one of the most critical barriers to nuclear safety. Its integrity under extreme loads, such as earthquakes, directly impacts the risk of nuclear leakage. Under earthquakes, damage to the containment structure may result from the combined effects of multiple mechanisms, including local material failure, global deformation overshoot, and energy accumulation. Traditional damage assessment methods rely on simplified assumptions based on single physical quantities (such as vertex displacement, interlayer displacement angle, or accumulated energy), neglecting the synergistic effects of multiple fields. Displacement-based thresholds fail to capture the progressive material degradation mechanism induced by energy accumulation, while energy dissipation metrics may be insensitive to brittle cracking in regions sensitive to local strain rates. These limitations are particularly pronounced in near-fault pulse earthquakes and long-duration ground motion sequences, whose complex spectral characteristics lead to spatiotemporal heterogeneity in damage mechanisms. A single metric cannot quantify the interaction between stress redistribution and energy flow during nonlinear dynamic processes. International nuclear power safety regulations emphasize that existing methods struggle to reconcile the conflict between local damage initiation and global functional loss under the "zero failure" safety goal. There is an urgent need to achieve physical integrity in damage criteria through multi-physics fusion modeling.

[0003] As the last barrier to nuclear safety, the seismic performance assessment technology of nuclear power plant containment has long been limited by the limitations of traditional single-index damage models, which are specifically reflected in the following aspects: (1) The one-sidedness of a single evaluation index. Traditional damage assessment methods rely on a single physical quantity to characterize damage and can only reflect one aspect of the structural response. (2) There is a lack of a unified quantitative standard between different damage indices. Existing evaluation methods use a variety of damage indicators, but the correlation and normalization criteria between indicators are missing, resulting in insufficient comparability and integration of results. (3) Existing vulnerability analysis methods do not adequately characterize the relationship between multiple seismic motion parameters and structural failure probability, and fail to effectively quantify the nonlinear correlation between the cumulative effect of multi-factor damage and failure probability, resulting in deviations in the prediction of failure probability under complex earthquake inputs.

[0004] Therefore, the prior art still has defects. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators in order to address the above-mentioned defects of the prior art. The technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present invention provides a method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators, wherein the method comprises:

[0007] Define a generalized damage index that integrates multiple evaluation indicators, select multiple sub-damage indicators, and standardize and normalize the multiple sub-damage indicators to obtain a new structural damage index that integrates multiple evaluation indicators;

[0008] Establish a finite element model of the nuclear power plant containment, conduct incremental dynamic analysis of the nuclear power plant containment structure, and extract damage parameters;

[0009] Based on the extracted damage parameters, a comprehensive damage index with multiple evaluation indicators is calculated to complete the vulnerability analysis and earthquake vulnerability curve construction.

[0010] In one implementation, the core goal of the generalized damage index is to establish a multi-dimensional damage characterization system that can comprehensively reflect the combined effects of local material degradation, overall geometric instability, and energy accumulation and dissipation through multi-physics field fusion modeling.

[0011] In one implementation, the selecting of the multi-substance damage indicator includes:

[0012] Determine the number and type of sub-damage indicators based on the structural characteristics and the type of load it bears.

[0013] According to the requirements for sub-damage index selection, combined with the traditional damage index used to study the performance of structural elements and evaluate the degree of structural damage, the local sub-damage index and the overall sub-damage index are determined.

[0014] In one implementation, the generalized damage index includes a local damage index applicable to a component and a global damage index applicable to a structure, which can be expressed as:

[0015] DI m =w local DI local +w global DI global

[0016] Among them, w local ,w global are the local damage index weight coefficient and the overall damage index weight coefficient, DI local ,DI global They are local damage index and global damage index respectively.

[0017] In one implementation, the containment structure of a nuclear power plant consists of a cylindrical wall and a semicircular dome. A finite element model is established using layered shell units, and material properties are assigned to each layer. The elastic modulus, Poisson's ratio, density, and plastic strain of the material are specified. Perforations are set at appropriate locations to simulate through-holes, and loads and boundary conditions are applied to the finite element model based on actual engineering conditions.

[0018] In one implementation, the method further includes:

[0019] Before incremental dynamic analysis, the natural seismic waves need to be amplitude modulated and 10-20 representative seismic waves are selected. Their spectral characteristics must match the natural vibration period of the nuclear power plant containment structure and site conditions.

[0020] In one implementation, the extracted damage parameters include displacement response, hysteretic energy dissipation, and concrete tensile damage distribution;

[0021] When constructing the seismic vulnerability curve, peak ground acceleration and spectral acceleration are selected as strength indicators. The peak ground acceleration reflects the time-domain intensity of the earthquake motion, and the spectral acceleration is used to characterize the spectral characteristics of the fundamental frequency matching of the structure.

[0022] The failure probability of the two strength indices is calculated respectively, and the structural failure probability curve under a single index is obtained.

[0023] In a second aspect, an embodiment of the present invention further provides a nuclear power plant containment structure seismic vulnerability analysis system based on the fusion of multiple evaluation indicators, wherein the system is used to implement the steps of the nuclear power plant containment structure seismic vulnerability analysis method based on the fusion of multiple evaluation indicators described in any of the above solutions, and the system includes:

[0024] The damage index analysis module is used to define a generalized damage index that integrates multiple evaluation indicators, select multiple sub-damage indicators, and standardize and normalize the multiple sub-damage indicators to obtain a new structural damage index that integrates multiple evaluation indicators;

[0025] Model building and parameter extraction module, used to build a finite element model of the nuclear power plant containment, perform incremental dynamic analysis on the nuclear power plant containment structure and extract damage parameters;

[0026] The earthquake vulnerability analysis module is used to calculate the comprehensive damage index of multiple evaluation indicators based on the extracted damage parameters, complete the vulnerability analysis and construct the earthquake vulnerability curve.

[0027] In a third aspect, an embodiment of the present invention further provides a terminal, wherein the terminal includes a memory, a processor, and a nuclear power plant containment structure seismic vulnerability analysis program based on the fusion of multiple evaluation indicators stored in the memory and runnable on the processor. When the processor executes the nuclear power plant containment structure seismic vulnerability analysis program based on the fusion of multiple evaluation indicators, the steps of the nuclear power plant containment structure seismic vulnerability analysis method based on the fusion of multiple evaluation indicators of any one of the above-mentioned schemes are implemented.

[0028] In a fourth aspect, an embodiment of the present invention also provides a computer-readable storage medium, wherein a program for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators is stored on the computer-readable storage medium, and the program for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators implements the steps of the method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators described in any one of the above-mentioned schemes on the computer-readable storage medium.

[0029] Beneficial Effects: Compared with existing technologies, the present invention provides a seismic vulnerability analysis method for nuclear power plant containment structures based on the fusion of multiple evaluation indicators. The present invention first defines a generalized damage index for the fusion of multiple evaluation indicators, selects multiple sub-damage indicators, and standardizes and normalizes these indicators to obtain a novel structural damage index that integrates multiple evaluation indicators. Then, a finite element model of the nuclear power plant containment is established, and incremental dynamic analysis of the containment structure is performed to extract damage parameters. Finally, a comprehensive multi-evaluation indicator damage index is calculated based on the extracted damage parameters, completing the vulnerability analysis and seismic vulnerability curve construction. By integrating multiple evaluation indicators, the present invention proposes a novel structural damage index that is compatible with structural characteristics and applicable to multiple scenarios. This overcomes the limitation of traditional single indicators that cannot balance brittle failure, cumulative damage, and local failure. Using this index, a seismic vulnerability analysis method for nuclear power plant containment structures is proposed, demonstrating excellent applicability. This method comprehensively considers the co-evolutionary effects of displacement amplitude, energy dissipation, and damage distribution to more comprehensively reflect the overall performance of the structure under seismic action. Based on a multi-index collaborative evaluation damage model and a unified quantitative fusion framework, the present invention effectively solves the problems of insufficient correlation and normalization between different damage indicators, ensuring the scientific nature and comparability of the analysis results. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The present invention provides a flowchart of a preferred embodiment of a method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators.

[0031] Figure 2 A schematic diagram of the technical route of a method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators provided in an embodiment of the present invention.

[0032] Figure 3 This is a flowchart of damage index normalization processing in the seismic vulnerability analysis method of nuclear power plant containment structure based on multi-evaluation index fusion provided by an embodiment of the present invention.

[0033] Figure 4 A schematic diagram of the architecture of a nuclear power plant containment structure seismic vulnerability analysis system based on the fusion of multiple evaluation indicators provided in an embodiment of the present invention.

[0034] Figure 5 This is a functional block diagram of a terminal provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents, operations, or steps, nor must they be executed in the order described. For example, some operations or steps may be decomposed, combined, or partially merged, so the actual execution order may vary depending on the actual situation.

[0037] It should be understood that the terms used in this specification are only for the purpose of describing particular embodiments and are not intended to limit the present invention. As used in the specification and appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0038] It should be understood that, to facilitate a clear description of the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, terms such as "first" and "second" are used to distinguish between identical or similar items with substantially the same functions and effects. For example, the first control information and the second control information are merely used to distinguish different control information and do not limit their order.

[0039] Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0040] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0041] The seismic vulnerability analysis method of the nuclear power plant containment structure based on the fusion of multiple evaluation indicators of the present invention can be applied to terminals, including intelligent product terminals such as computers, televisions and mobile phones. Specifically, Figure 1 As shown in , the seismic vulnerability analysis method of the nuclear power plant containment structure based on the fusion of multiple evaluation indicators in this embodiment includes the following steps:

[0042] Step S100: defining a generalized damage index integrating multiple evaluation indicators, selecting multiple sub-damage indicators, and performing standardization and normalization on the multiple sub-damage indicators to obtain a new structural damage index integrating multiple evaluation indicators;

[0043] Step S200: establishing a finite element model of the nuclear power plant containment, performing incremental dynamic analysis on the nuclear power plant containment structure, and extracting damage parameters;

[0044] Step S300: Calculate the comprehensive damage index of multiple evaluation indicators based on the extracted damage parameters to complete the vulnerability analysis and the construction of the earthquake vulnerability curve.

[0045] This embodiment aims to construct a multi-field fusion multi-index damage assessment system to optimize the accuracy and reliability of seismic vulnerability analysis of nuclear power plant containment. The specific objectives are as follows: (1) Establish a damage model that integrates multi-index collaborative evaluation, break through the technical limitations of the traditional single-index model, and propose accurate indicators for damage assessment of containment structures under earthquake action. (2) Construct a unified and quantitative damage index fusion framework to solve the problem of weight distribution and normalization calibration among multiple damage indicators, and achieve standardization and universality of the evaluation system. (3) Propose a probabilistic analysis method that integrates multiple parameters of seismic motion and comprehensive structural damage index, establish a quantitative mapping relationship between damage evolution and failure threshold, analyze the failure probability density distribution characteristics under different seismic motion input combinations, and improve the assessment accuracy under complex seismic motion scenarios.

[0046] Combine Figure 2 As shown, this embodiment includes two aspects: a novel structural damage index calculation method based on the fusion of multiple evaluation indicators, and a seismic vulnerability analysis method for nuclear power plant containment structures based on the novel damage index. In this embodiment, the synergistic effects of multiple mechanisms occurring during structural damage are difficult to describe using a single damage indicator. A generalized damage index definition that integrates multiple evaluation indicators is proposed. Each sub-damage indicator is determined based on the structural characteristics and the load characteristics it experiences. Weighting factors are assigned based on the degree of damage contribution. The multiple sub-damage indicators are then standardized and normalized to produce a novel structural damage index that integrates multiple evaluation indicators.

[0047] Specifically, this embodiment first defines a generalized damage index that integrates multiple evaluation indicators. The damage evolution of the containment structure of a nuclear power plant has nonlinear and multi-mechanism coupling characteristics. The traditional indicator model only targets a single scale and ignores the competition-synergy effect between different damage modes. It is difficult to fully characterize the degradation process of mechanical behavior under earthquake action. The core goal of the generalized damage index is to establish a multi-dimensional damage characterization system that can comprehensively reflect the joint action of multiple factors such as local material degradation (such as concrete cracking, steel bar buckling), overall geometric instability (such as excessive interlayer displacement) and energy accumulation and dissipation (such as plastic strain energy accumulation effect) through multi-physical field fusion modeling, as shown below:

[0048]

[0049] Among them, DI m DI is a new structural damage index that integrates multiple damage evaluation indicators. i is the structural damage index calculated based on the traditional single evaluation index, ω i is the damage index weight factor determined by the damage contribution degree.

[0050] Next, this embodiment selects multiple sub-damage indicators. Specifically, when constructing a multi-indicator damage overall damage index, it is necessary to first determine the number and type of sub-damage indicators based on the structural characteristics and the type of load it bears. The sub-damage indicators should meet the following requirements: a) DI i It is a dimensionless quantity with a value range of [0,1], where DI i =0 means that the structure is not damaged, DI i =1 indicates complete structural damage; b) DI i It should be physically interpretable and be able to classify the damage state of the structure through different ranges of values; c) DI i The physical quantities in the DI should be able to reflect the healthy state and damaged state of the structure; d) i It should have multi-scale applicability and can be used to evaluate the damage degree of local components or the global structure.

[0051] Based on the above-mentioned sub-damage index selection requirements and combined with traditional damage indices widely used to study the performance of structural components and assess the degree of structural damage, the following Tables 1 and 2 provide the recommended local sub-damage index and global sub-damage index, respectively.

[0052] Table 1 Local sub-damage indicators used to construct the generalized damage index

[0053]

[0054]

[0055]

[0056]

[0057] Table 5 Overall sub-damage indicators used to construct the generalized damage index

[0058]

[0059]

[0060] It should be noted that Tables 1 and 2 provide some common sub-damage indices. More damage indices can also be used in the calculation of the generalized damage index. The appropriate damage index should be selected based on the structural characteristics and loading conditions in the specific scenario.

[0061] Furthermore, according to the definition requirements of damage index, when selecting different damage indices, it is necessary to ensure that the value of the damage index is between [0, 1]. Since the damage indices proposed earlier mainly focus on the degree of change in structural characteristics, different calculation methods lack unified regulations when evaluating structural damage. Therefore, there may be cases where the calculation result is greater than 1 or the structure has been completely damaged but the damage index value is less than 1. In this case, the calculation results need to be standardized. The processing steps are as follows: Figure 3 shown.

[0062] The damage indices listed in Tables 1 and 2 include local damage indices applicable to components and global damage indices applicable to structures. When using damage indices of two scales at the same time, Equation (1) can be rewritten as follows:

[0063] DI m =w local DI local +w global DI global (2)

[0064] Where: w local ,w global are the weight coefficients of local and overall damage indicators, DI local ,DI global They are local damage index and global damage index respectively.

[0065] Furthermore, the damage index is normalized according to the degree of damage contribution:

[0066]

[0067] When the local damage index and the global damage index are composed of multiple sub-damage indices, Equation 2 can be rewritten as follows:

[0068]

[0069] Where: w i ,w j are the weight coefficients of local and global sub-damage indicators, DI i ,DI j are the local and global sub-damage indices, respectively.

[0070] The local damage index neutron damage index weight coefficient can be obtained by solving the following formula:

[0071]

[0072] Similarly, the damage index weight coefficient in the global damage index can be calculated by the following formula:

[0073]

[0074] Substituting the damage index weight coefficients calculated from equations (5) and (6) into equation (4) yields the final expression for a new structural damage index that integrates multiple evaluation indicators. Calculating this damage index provides specific, quantifiable parameters for comprehensive damage assessment of structures under different loading conditions, laying the foundation for subsequent vulnerability analysis of structures under earthquakes.

[0075] Furthermore, this embodiment establishes a finite element model of the containment shell and performs incremental dynamic analysis on the structure to obtain the response and damage distribution of the structure under different strength indicators. The displacement response, hysteretic energy dissipation, and concrete tensile damage distribution are extracted to calculate the three-indicator structural damage index. The vulnerability analysis is completed and the structural failure probability curve is drawn. The characteristics of the structural failure probability distribution under multiple indicators are intuitively presented, thereby achieving the purpose of improving the accuracy of the structural failure probability analysis.

[0076] Specifically, when establishing a finite element model of a nuclear power plant's containment structure, which serves as the structural support for subsequent vulnerability analysis, it is necessary to establish a structural model that balances both reproducibility and computational efficiency to ensure the accuracy of the analysis results. The containment structure primarily consists of a cylindrical wall and a semicircular dome. Because the wall thickness is less than 1 / 10 of the radius, it can be considered a shell structure. A finite element model is established using layered shell elements, assigning material properties to each layer and specifying parameters such as the elastic modulus, Poisson's ratio, density, and plastic strain. Perforations are placed at appropriate locations to simulate through-holes, and loads and boundary conditions are applied to the model based on actual engineering conditions.

[0077] Before the incremental dynamic analysis, this embodiment needs to first perform amplitude modulation on the natural earthquake waves, and select 10-20 representative earthquake waves, whose spectral characteristics need to match the natural vibration period of the structure and the site conditions. The amplitude modulation of earthquake motion often uses peak acceleration (PGA) or specific period spectrum acceleration (Sa(T□)) as the intensity index, and gradually increases at fixed intervals. After each amplitude modulation, run a nonlinear time history analysis to record key response parameters such as structural displacement, acceleration, and hysteresis energy. After the analysis is completed, save the response data at all intensity levels for subsequent extraction of damage parameters. Damage parameters need to quantify the degree of local and overall damage from the structural response. Displacement parameters include the maximum inter-story displacement angle, vertex displacement ratio, etc., which directly reflect the deformation capacity; energy parameters such as damage dissipation energy, plastic deformation hysteresis energy dissipation, etc. can characterize the cumulative damage of the structure under cyclic action; material parameters such as the distribution of concrete tensile damage can reflect the overall functional loss caused by local damage to the structure.

[0078] Specifically, the extracted damage parameters include displacement response, hysteretic energy dissipation, and concrete tensile damage distribution. After extracting the loss parameters, a displacement-based damage index, an energy-based damage index, and a tensile damage distribution-based damage index were selected from the multi-element damage indices to construct a multi-index fusion damage index. This index takes into account non-cumulative damage, cumulative damage, and local damage, better reflecting the comprehensive state of the damaged structure.

[0079] ① Damage index based on displacement:

[0080]

[0081] Among them, Δ max is the maximum displacement of the vertex in the nonlinear time history analysis of the structure, Δ y is the vertex yield displacement under pseudo-static loading.

[0082] ②Energy-based damage indicators:

[0083]

[0084] E W =E K +E S +E D +E P +E V (9)

[0085] Where: E W is the external input energy, E D is the damage dissipation energy, E P is the inelastic dissipation energy, E K is kinetic energy, E S is the recoverable strain energy, EV It is the viscous dissipation energy.

[0086] ③ Damage index based on tensile damage distribution:

[0087]

[0088] In the formula: dt is the tensile damage parameter, and ds is the differential of the structural size unit.

[0089] By standardizing and normalizing the above sub-damage indices, the damage index DI for subsequent vulnerability analysis can be calculated. m .

[0090] (3) Construction of structural vulnerability curves based on a new damage index

[0091] The definitions of the structural performance level (PL) and the limit state (LS) are the core theoretical basis of vulnerability analysis. Based on the multi-index fusion method and combined with the structural function and safety requirements, the performance state of the structure in this invention is divided into 4 categories: a) basically intact (DI ≤ 0.2), indicating that the structure is in the elastic stage and meets the functional integrity; b) slightly damaged (0.2 < DI ≤ 0.5), indicating that plastic deformation occurs in local areas, but the residual deformation is still controllable; c) severely damaged (0.5 < DI ≤ 0.8), a large number of cracks or crushing occur in the concrete of the key area, and the structural function cannot be guaranteed, and immediate repair is required; d) collapse (DI > 0.8), the overall structure is unstable or the key load-bearing system is severely damaged, and the structural function is completely lost.

[0092] The intensity index (IM) is the bridge connecting the characteristics of ground motion and the structural response. In this embodiment, the peak ground acceleration PGA and the spectral acceleration Sa are selected as the intensity indices. The peak ground acceleration reflects the time-domain intensity of ground motion, and the spectral acceleration characterizes the spectral characteristics matching the fundamental frequency of the structure. When calculating a single vulnerability curve, the failure probability is calculated for the two intensity indices respectively, and the structural failure probability curve under a single index is obtained.

[0093]

[0094] Among them, EDP is the engineering demand parameter, is the engineering demand parameter corresponding to the LS i state, and LS i is the i-th limit state.

[0095] Assume that the engineering demand parameter follows a lognormal distribution, and the engineering demand parameter is defined as a multi-index fusion damage index. Then, the probability density function of EDP can be obtained from Equation (l2):

[0096]

[0097] Among them, the logarithmic median u lnx and the logarithmic standard deviation σ lnx It can be calculated by formula 5-13 and formula 5-14 respectively:

[0098]

[0099] Where: u x is the median value of the new damage index under earthquake action, σ x is the standard deviation of the damage index, δ x is the coefficient of variation.

[0100] Therefore, the failure probability of a structure under a given strength index can be calculated according to the following formula:

[0101]

[0102] Where: Φ(·) is the cumulative normal distribution function.

[0103] By applying different seismic motion records to the structure and performing nonlinear time-history analysis to obtain the structural response and calculating the corresponding damage index, the failure probability of the structure under different strength indicators can be obtained. However, these failure probabilities are a series of discrete values, and the structural fragility curve needs to be constructed through fitting. Polynomial regression can be used for fitting.

[0104] y=a0+a1x+a2x 2 +L+a m x m (17)

[0105] Where: y is the probability of structural failure, x is the earthquake intensity index, (a0, a1, L, a m ) is the unknown coefficient.

[0106] Convert the polynomial fitting problem into linear regression and construct the design matrix X and matrix y:

[0107]

[0108] Construct coefficient vector a=(a0,a1,L,a m ) T , the polynomial function can be rewritten as follows:

[0109] y=aX (19)

[0110] The coefficient vector can be solved by the least squares method:

[0111] a=(X T X) -1 X T y(20)

[0112] The earthquake vulnerability curve can be constructed according to the above method.

[0113] By integrating multiple evaluation indicators, this paper proposes a novel structural damage index that is compatible with structural characteristics and applicable to multiple scenarios. This overcomes the limitation of traditional single indicators that cannot balance brittle failure, cumulative damage, and local failure. Using this index, a seismic vulnerability analysis method for nuclear power plant containment structures is proposed, demonstrating excellent applicability. This method comprehensively considers the co-evolutionary effects of displacement amplitude, energy dissipation, and damage distribution to more comprehensively reflect the overall performance of the structure under earthquake action. Based on a multi-indicator collaborative evaluation damage model and a unified quantitative fusion framework, the present invention effectively addresses the lack of correlation and normalization problems between different damage indicators, ensuring the scientific nature and comparability of the analysis results. By introducing an adaptive weighting function for damage contribution and dynamically correcting the multi-field fusion relationship, the model can adapt to complex seismic input conditions, improving the accuracy and robustness of structural damage assessment. For failure probability prediction under complex seismic scenarios, the present invention establishes a failure probability curve using a comprehensive damage index, quantitatively analyzing the nonlinear relationship between damage evolution and failure threshold, significantly improving the failure probability assessment capability of nuclear power plant containment under near- and far-field earthquake inputs. With the help of a new damage index calculation framework, the present invention realizes efficient and reliable seismic vulnerability analysis of containment structures, provides comprehensive technical support for the seismic design, risk management and safety assessment of nuclear power plants, and is of great significance in ensuring the safe operation of nuclear power plants and social public safety.

[0114] Based on the above embodiment, the present invention also provides a nuclear power plant containment structure seismic vulnerability analysis system based on the fusion of multiple evaluation indicators, which is used to implement the steps in the above method embodiment, specifically, Figure 4 As shown, the system includes: a damage index analysis module 10, a model building and parameter extraction module 20, and a seismic vulnerability analysis module 30. The damage index analysis module 10 is used to define a generalized damage index that integrates multiple evaluation indicators, select multiple sub-damage indicators, and standardize and normalize the multiple sub-damage indicators to obtain a new structural damage index that integrates multiple evaluation indicators. The model building and parameter extraction module 20 is used to establish a finite element model of the nuclear power plant containment, perform incremental dynamic analysis on the nuclear power plant containment structure, and extract damage parameters. The seismic vulnerability analysis module 30 is used to calculate a comprehensive damage index based on multiple evaluation indicators based on the extracted damage parameters, completing vulnerability analysis and seismic vulnerability curve construction.

[0115] The working principles of each module in the nuclear power plant containment structure seismic vulnerability analysis system based on multi-evaluation index fusion in this embodiment are the same as the principles of each step in the above method embodiment, and will not be repeated here.

[0116] Each module in the aforementioned multi-evaluation-index-fusion-based seismic vulnerability analysis system for nuclear power plant containment structures can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor within a terminal in hardware form, or stored in a memory within the terminal in software form, allowing the processor to call and execute the corresponding operations of each module.

[0117] Based on the above embodiment, the present invention further provides a terminal, the principle block diagram of the terminal can be as follows: Figure 5 The terminal may include one or more processors 100 ( Figure 5 Only one is shown in the figure), a memory 101, and a computer program 102 stored in the memory 101 and executable on one or more processors 100. For example, a program for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators. When one or more processors 100 execute the computer program 102, each step in the embodiment of the method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators can be implemented. Alternatively, when one or more processors 100 execute the computer program 102, the functions of each module / unit in the embodiment of the system for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators can be implemented, which is not limited here.

[0118] In one embodiment, the processor 100 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0119] In one embodiment, the memory 101 may be an internal storage unit of an electronic device, such as a hard disk or memory of the electronic device. The memory 101 may also be an external storage device of the electronic device, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device. Furthermore, the memory 101 may include both an internal storage unit of the electronic device and an external storage device. The memory 101 is used to store computer programs and other programs and data required by the terminal. The memory 101 may also be used to temporarily store data that has been output or is about to be output.

[0120] Those skilled in the art will understand that Figure 5 The principle block diagram shown in the figure is only a block diagram of a partial structure related to the solution of the present invention, and does not constitute a limitation on the terminal to which the solution of the present invention is applied. The specific terminal may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0121] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, operating database or other media used in the embodiments provided by the present invention may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct RAMbus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for seismic vulnerability analysis of nuclear power plant containment structures based on the fusion of multiple evaluation indicators, characterized in that: The method comprises: Define a generalized damage index that integrates multiple evaluation indicators, select multiple sub-damage indicators, and standardize and normalize the multiple sub-damage indicators to obtain a new structural damage index that integrates multiple evaluation indicators; Establish a finite element model of the nuclear power plant containment, conduct incremental dynamic analysis of the nuclear power plant containment structure, and extract damage parameters; Based on the extracted damage parameters, a comprehensive damage index with multiple evaluation indicators is calculated to complete the vulnerability analysis and earthquake vulnerability curve construction.

2. The method for seismic vulnerability analysis of nuclear power plant containment structures based on fusion of multiple evaluation indicators according to claim 1 is characterized in that: The core goal of the generalized damage index is to establish a multi-dimensional damage characterization system that can comprehensively reflect the combined effects of local material degradation, overall geometric instability and energy accumulation and dissipation through multi-physics field fusion modeling.

3. The method for seismic vulnerability analysis of nuclear power plant containment structures based on fusion of multiple evaluation indicators according to claim 1, characterized in that: The selected multi-element damage indicators include: Determine the number and type of sub-damage indicators based on the structural characteristics and the type of load it bears. According to the requirements for sub-damage index selection, combined with the traditional damage index used to study the performance of structural elements and evaluate the degree of structural damage, the local sub-damage index and the overall sub-damage index are determined.

4. The method for seismic vulnerability analysis of nuclear power plant containment structures based on fusion of multiple evaluation indicators according to claim 1, characterized in that: The generalized damage index includes the local damage index applicable to components and the global damage index applicable to structures, which can be expressed as: IN m =w local IN local +w global IN global Among them, w local ,w global are the local damage index weight coefficient and the overall damage index weight coefficient, DI local ,DI global They are local damage index and global damage index respectively.

5. The method for seismic vulnerability analysis of nuclear power plant containment structures based on fusion of multiple evaluation indicators according to claim 1, characterized in that: The containment structure of a nuclear power plant consists of a cylindrical wall and a semicircular dome. A finite element model is established using layered shell elements. Material properties are assigned to each layer, and the elastic modulus, Poisson's ratio, density, and plastic strain of the material are specified. Perforations are set at appropriate locations to simulate through-holes, and loads and boundary conditions are applied to the finite element model based on actual engineering conditions.

6. The method for seismic vulnerability analysis of nuclear power plant containment structures based on fusion of multiple evaluation indicators according to claim 1, characterized in that: The method further comprises: Before incremental dynamic analysis, the natural seismic waves need to be amplitude modulated and 10-20 representative seismic waves are selected. Their spectral characteristics must match the natural vibration period of the nuclear power plant containment structure and site conditions.

7. The method for seismic vulnerability analysis of nuclear power plant containment structures based on fusion of multiple evaluation indicators according to claim 1, characterized in that: The extracted damage parameters include displacement response, hysteretic energy dissipation, and concrete tensile damage distribution; When constructing the seismic vulnerability curve, peak ground acceleration and spectral acceleration are selected as strength indicators. The peak ground acceleration reflects the time-domain intensity of the earthquake motion, and the spectral acceleration is used to characterize the spectral characteristics of the fundamental frequency matching of the structure. The failure probability of the two strength indices is calculated respectively, and the structural failure probability curve under a single index is obtained.

8. A seismic vulnerability analysis system for nuclear power plant containment structures based on the fusion of multiple evaluation indicators, characterized in that: The system is used to implement the steps of the method for analyzing seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators as described in any one of claims 1 to 7, and the system comprises: The damage index analysis module is used to define a generalized damage index that integrates multiple evaluation indicators, select multiple sub-damage indicators, and standardize and normalize the multiple sub-damage indicators to obtain a new structural damage index that integrates multiple evaluation indicators; Model building and parameter extraction module, used to build a finite element model of the nuclear power plant containment, perform incremental dynamic analysis on the nuclear power plant containment structure and extract damage parameters; The earthquake vulnerability analysis module is used to calculate the comprehensive damage index of multiple evaluation indicators based on the extracted damage parameters, complete the vulnerability analysis and construct the earthquake vulnerability curve.

9. A terminal, characterized in that: The terminal includes a memory, a processor, and a nuclear power plant containment structure seismic vulnerability analysis program based on the fusion of multiple evaluation indicators stored in the memory and runnable on the processor. When the processor executes the nuclear power plant containment structure seismic vulnerability analysis program based on the fusion of multiple evaluation indicators, the steps of the nuclear power plant containment structure seismic vulnerability analysis method based on the fusion of multiple evaluation indicators as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a program for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators. The program for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators implements the steps of the method for analyzing the seismic vulnerability of a nuclear power plant containment structure based on the fusion of multiple evaluation indicators as described in any one of claims 1 to 7 on the computer-readable storage medium.

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