A method and system for calculating earthquake damage performance of submarine tunnels

Abstract

The present invention provides a method and system for calculating the earthquake damage performance of an undersea tunnel, and relates to the technical fields of structural engineering and engineering mechanics. The present invention determines the most unfavorable earthquake vibration input parameters by analyzing the time-frequency characteristics of the earthquake vibration signal in the sea area, and uses these parameters to perform quasi-static experiments, calculate the impact stress of each part of the tunnel, and generate seismic stress limits, perform elastic-plastic earthquake response analysis, calculate shear stress, generate material fatigue limits, calculate the seismic performance and seismic margin of the current tunnel, generate seismic deformation limits, and generate a seismic damage index by combining various limits, and compare it with the earthquake damage index to judge the degree of damage to the tunnel. The present invention realizes the seismic performance evaluation and damage degree judgment of the undersea tunnel through technical means such as seismic signal analysis, quasi-static experiments, and elastic-plastic response analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of structural engineering and engineering mechanics, and in particular to a method and system for calculating earthquake damage performance of a submarine tunnel. Background Art

[0002] As an important infrastructure, undersea tunnels usually carry a large amount of traffic, including railways and roads. When an earthquake occurs, the structural safety of the tunnel is directly related to the safety of people and transportation inside. By accurately calculating the performance of the tunnel under the action of an earthquake, it can be ensured that its design is sufficient to withstand the expected earthquake force, thereby avoiding or minimizing casualties and economic losses during disasters. Understanding the type and extent of damage that the tunnel may suffer in an earthquake can help relevant departments develop more effective emergency response plans. This includes rapid assessment of damage, decision on whether to close the tunnel, and optimization of strategies for rescue and repair work.

[0003] In the prior art, the authorization announcement number CN115840984B discloses a method, device and terminal equipment for calculating the damage performance of a tunnel structure. The method obtains the basic parameters of the tunnel to be calculated, and constructs a tunnel structure model based on the basic parameters of the tunnel to be calculated; determines the seismic wave simulation parameters based on the basic parameters of the tunnel to be calculated, and generates simulated seismic waves according to the seismic wave simulation parameters; applies the simulated seismic waves to the tunnel structure model to obtain structural damage performance data; and calculates the tunnel structure damage performance based on the structural damage performance data.

[0004] Insufficient existing technology:

[0005] In the prior art, although the actual situation can be simulated well by simulating seismic waves applied to the tunnel structure model, this method relies on the accuracy of the seismic wave simulation parameters. If the selection of seismic wave simulation parameters is not accurate enough or cannot fully cover all possible earthquake scenarios, the simulation results may deviate from the actual earthquake response. This deviation may affect the accuracy of the final damage performance assessment, thereby affecting the design and safety assessment of the tunnel;

[0006] Secondly, existing technologies may not fully consider the complex geological conditions and dynamic changes in the tunnel's surrounding environment when simulating tensile damage to tunnel structures. Soil-structure interactions under earthquakes are very complex, especially under different types of soil conditions, which may have a significant impact on the response of tunnel structures, and existing technologies may not be able to fully simulate this complexity. In addition, tunnels may experience multiple earthquakes during construction and use, and existing technologies may not be able to effectively simulate cumulative damage and long-term performance changes, which limits their predictive ability and reliability in actual engineering applications.

[0007] Therefore, it is necessary to provide a method and system for calculating the earthquake damage performance of an undersea tunnel to solve the above problem.

[0008] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0009] The purpose of the present invention is to provide a method and system for calculating the seismic damage performance of an undersea tunnel, so as to solve the problems raised in the above-mentioned background technology.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] A method for calculating earthquake damage performance of a submarine tunnel, comprising the following specific steps:

[0012] Step 1: Set up multiple collection locations in the submarine tunnel to collect marine earthquake vibration signals and analyze their time-frequency characteristics to determine the maximum acceleration and effective acceleration;

[0013] Step 2: Based on the calculated maximum acceleration and effective acceleration, a quasi-static test is conducted on the submarine tunnel to calculate the impact stress of the earthquake on various parts of the tunnel, and the seismic stress limit is generated by integrating the impact stress of various parts of the tunnel;

[0014] Step 3: Analyze the elastic-plastic earthquake response of the tunnel, calculate the shear stress of each part of the tunnel caused by the earthquake, and generate the material fatigue limit value by integrating the shear stress of each part;

[0015] Step 4: Based on a comprehensive analysis of the submarine tunnel, the seismic performance and seismic margin of the current tunnel are calculated, and the seismic deformation limit is generated using the calculated seismic performance and seismic margin;

[0016] Step 5: Using the calculated seismic stress limit, material fatigue limit and seismic deformation limit, a seismic damage index is comprehensively generated, and an undersea tunnel earthquake damage index is established. The index is compared with the damage index to determine the severity of the damage.

[0017] Furthermore, the sea area earthquake vibration data is collected and its time-frequency characteristics are analyzed to determine the maximum acceleration and effective acceleration. The method is based on:

[0018] Collect sea area seismic vibration data from seismic monitoring stations, ocean sensors or historical seismic databases, use a low-pass filter to remove high-frequency noise, retain effective seismic signals, and use the short-time Fourier transform formula to process the sea area seismic vibration data. The formula is:

[0019] ;

[0020] in, Indicates at time and frequency The short-time Fourier transform result under the condition of The spectrum information of all signals on Indicates the input marine earthquake vibration signal at time The value of represents a window function, represents the complex exponential function, represents the imaginary unit, represents the angular frequency of the signal, Indicates at time The integral on Indicates time delay;

[0021] By using short-time Fourier transform to perform time-frequency analysis on seismic data, the energy distribution and change trend of the signal at different time points and frequencies are obtained, and the maximum acceleration and effective acceleration of seismic vibration are extracted. By simulating the seismic response of the tunnel under different seismic input conditions, the vibration mode that can cause the maximum structural damage is selected, that is, the most unfavorable seismic vibration input parameter. The formula is:

[0022] ;

[0023] ;

[0024] in, Indicates The maximum acceleration of each part, that is, the maximum absolute value of acceleration in the earthquake vibration signal, Indicates The earthquake vibration signal at each location in time The acceleration under Indicates The effective acceleration of each part, Represents the total duration of the seismic signal.

[0025] Furthermore, a quasi-static test was conducted on the submarine tunnel to calculate the impact stress of the earthquake on various parts of the tunnel. The method used is:

[0026] By applying an equivalent static load to simulate the dynamic impact of the earthquake on the tunnel structure, the inertial force generated by the earthquake vibration is converted into a static load. The maximum acceleration and effective acceleration obtained by calculation are used as earthquake input parameters to calculate the equivalent static load. The formula is as follows:

[0027] ;

[0028] in, represents the equivalent static load, Indicates the overall quality of the tunnel;

[0029] In practical application calculations, different parts of the tunnel have different masses and accelerations. The equivalent static loads of various parts of the tunnel are calculated using a general formula. The impact stresses of various parts of the tunnel are calculated based on the equivalent static loads of various parts of the tunnel calculated and the force-bearing areas of various parts of the tunnel. The formula used is:

[0030] ;

[0031] ;

[0032] in, Indicates the tunnel The equivalent static load of each part, Indicates the tunnel The quality of each part, , Respectively represent the tunnel The maximum acceleration and effective acceleration of each part, Indicates the tunnel Impact stress at each part, Indicates the tunnel The force-bearing area of ​​each part, Indicates the index of different parts in the tunnel.

[0033] Furthermore, the impact stress at each part of the tunnel is comprehensively considered to generate the seismic stress limit value, and the formula based on it is:

[0034] ;

[0035] in, represents the seismic stress limit, Indicates the number of collection locations in the tunnel.

[0036] Furthermore, based on the analysis of the elastic-plastic seismic response of the tunnel, the shear stress of the earthquake on various parts of the tunnel is calculated according to the following method:

[0037] By considering the elastic and plastic deformation behaviors of the material, simulating the response of the tunnel under seismic load, the finite element method is used for modeling and analysis, and a three-dimensional geometric model of the tunnel is established. The material property data of the tunnel structure and the surrounding soil are collected. The property data include elastic modulus, Poisson's ratio, yield strength and plastic hardening modulus. The three-dimensional geometric model is divided into finite element units, and the triangular unit is selected as the finite element unit type. The shear strain is calculated by the node displacement, and the shear modulus is calculated by the elastic modulus and Poisson's ratio. The formula is as follows:

[0038] ;

[0039] ;

[0040] in, , Respectively represent Shear force and shear modulus at each part, , Respectively represent The node in the Horizontal and The vertical displacement, Indicates The elastic modulus of the material at each part, Indicates Poisson's ratio of the material in each part;

[0041] When the shear force exceeds the material yield, the shear force needs to consider the influence of yield strength and plastic hardening modulus. The shear stress of each triangular unit is calculated based on the comprehensive shear modulus and shear force. The formula is:

[0042] ;

[0043] in, Indicates The shear stress at each collection site, Indicates The shear modulus of the collected parts, represents the shear strain when the material yields, represents the yield strength of the material, Represents the plastic hardening modulus of the material.

[0044] Furthermore, the shear stress at each location is combined to generate the material fatigue limit, based on the following method:

[0045] The Miner damage accumulation algorithm is used to calculate the material fatigue limit. For each finite element, the number of stress cycles under earthquake action is calculated. According to the Miner damage accumulation method, the damage caused by a single stress cycle is first calculated, and then the damage of all finite elements is accumulated. The total damage is the material fatigue limit of a single part. The formula is:

[0046] ;

[0047] ;

[0048] in, Indicated in The first part The damage caused by the stress cycle Indicated in The first part The shear stress of a stress cycle, Indicated in The material fatigue limit of each part, represents the index of the damage cycle, represents the total number of injury cycles;

[0049] The material fatigue limit of the tunnel is generated by combining the material fatigue limit of each individual part, based on the following formula:

[0050] ;

[0051] in, Represents the material fatigue limit of the tunnel.

[0052] Furthermore, the seismic performance and seismic margin of the current tunnel are calculated based on the following formula:

[0053] ;

[0054] ;

[0055] in, , They represent seismic performance and seismic margin respectively. Indicates the pressure of the tunnel under the current earthquake, represents the equivalent static load, It represents the ultimate bearing capacity during design. It indicates the actual bearing capacity achieved under earthquake action.

[0056] Furthermore, the calculated seismic performance and seismic margin are used to generate seismic deformation limit values, based on the formula:

[0057] ;

[0058] in, Indicates the seismic deformation limit.

[0059] Furthermore, a comprehensive seismic damage index is generated, and an undersea tunnel earthquake damage index is established. The index is compared with the damage index to determine the severity of the damage. The formula is as follows:

[0060] ;

[0061] ;

[0062] in, represents the earthquake damage index of the submarine tunnel, represents the material fatigue limit, represents the seismic deformation limit, represents the seismic stress limit, Indicates the logical value of whether the damage is serious. When , it means that the seismic damage index does not exceed the earthquake damage index of the submarine tunnel, and the damage is not serious; when When the earthquake damage index exceeds the earthquake damage index of the submarine tunnel, the damage is serious. Indicates damage indicator.

[0063] The present invention further provides a submarine tunnel earthquake damage performance calculation system, the performance damage calculation system is used to execute the above-mentioned submarine tunnel earthquake damage performance calculation method, comprising:

[0064] A seismic signal acquisition and time-frequency analysis module, which is used to set multiple acquisition locations in the submarine tunnel, collect sea area seismic vibration signals and analyze their time-frequency characteristics to determine the maximum acceleration and effective acceleration;

[0065] A quasi-static experiment and impact stress calculation module, which is used to perform a quasi-static experiment on the submarine tunnel according to the calculated maximum acceleration and effective acceleration, calculate the impact stress of the earthquake on various parts of the tunnel, and generate a seismic stress limit value based on the impact stress of various parts of the tunnel;

[0066] An elastic-plastic earthquake response analysis module, which is used to analyze the elastic-plastic earthquake response of the tunnel, calculate the shear stress of the earthquake on each part of the tunnel, and generate the material fatigue limit value by integrating the shear stress of each part;

[0067] A seismic performance and margin assessment module, wherein the seismic performance and margin assessment module calculates the seismic performance and seismic margin of the current tunnel based on a comprehensive analysis of the submarine tunnel, and generates a seismic deformation limit value using the calculated seismic performance and seismic margin;

[0068] The seismic damage index generation and evaluation module is used to use the calculated seismic stress limit, material fatigue limit and seismic deformation limit to comprehensively generate a seismic damage index, establish an undersea tunnel earthquake damage index, compare the index with the damage index, and judge the severity of the damage.

[0069] Compared with the prior art, the present invention has the following beneficial effects:

[0070] The present invention first collects sea area earthquake vibration data and uses short-time Fourier transform to analyze the time-frequency characteristics of these data, thereby more accurately determining the most unfavorable earthquake vibration input parameters for the submarine tunnel. Compared with the existing technology, this improvement pays more attention to the real-time and representativeness of earthquake data, and can more comprehensively cover different earthquake scenarios, thereby reducing simulation deviations caused by inaccurate parameter selection and improving the accuracy of earthquake response simulation;

[0071] After calculating the maximum acceleration and the effective acceleration, the present invention not only conducts a quasi-static experiment to simulate the impact stress of the earthquake on various parts of the tunnel, but also conducts an elastoplastic earthquake response analysis to calculate the shear stress of the earthquake on various parts of the tunnel. This method combines the dynamic and static responses of the tunnel, making the evaluation more comprehensive and accurate. In addition, the detailed modeling using the finite element method further improves the accuracy of the simulation, and can take into account the elastic and plastic deformation behavior of the material, better simulate the response of the tunnel in an actual earthquake, and thus more comprehensively evaluate the degree of damage to the tunnel in an earthquake. Through this method, the severity of the damage to the tunnel can be judged more accurately, thereby providing more powerful data support for the design, construction and maintenance of the tunnel;

[0072] The present invention realizes accurate seismic performance evaluation and damage degree prediction of submarine tunnels under earthquake action through time-frequency analysis, quasi-static experiments and elastoplastic seismic response analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 It is a schematic diagram of the overall method flow of the present invention.

[0074] Figure 2 It is a schematic diagram of the system module flow of the present invention. DETAILED DESCRIPTION

[0075] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0076] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0077] Example:

[0078] See also Figure 1 , a method for calculating the earthquake damage performance of an undersea tunnel, the specific steps comprising:

[0079] Step 1: Set up multiple collection locations in the submarine tunnel to collect marine earthquake vibration signals and analyze their time-frequency characteristics to determine the maximum acceleration and effective acceleration;

[0080] Step 2: Based on the calculated maximum acceleration and effective acceleration, a quasi-static test is conducted on the submarine tunnel to calculate the impact stress of the earthquake on various parts of the tunnel, and the seismic stress limit is generated by integrating the impact stress of various parts of the tunnel;

[0081] Step 3: Analyze the elastic-plastic earthquake response of the tunnel, calculate the shear stress of each part of the tunnel caused by the earthquake, and generate the material fatigue limit value by integrating the shear stress of each part;

[0082] Step 4: Based on a comprehensive analysis of the submarine tunnel, the seismic performance and seismic margin of the current tunnel are calculated, and the seismic deformation limit is generated using the calculated seismic performance and seismic margin;

[0083] Step 5: Using the calculated seismic stress limit, material fatigue limit and seismic deformation limit, a seismic damage index is comprehensively generated, and an undersea tunnel earthquake damage index is established. The index is compared with the damage index to determine the severity of the damage.

[0084] It should be noted that by collecting data from marine seismic monitoring stations, sensors or historical databases and processing these data using short-time Fourier transforms, we can understand the time-frequency characteristics of seismic waves in detail. This analysis helps identify the most destructive frequency components and amplitudes in seismic waves, and provides a scientific basis for determining the most unfavorable seismic input parameters to be addressed in the design of undersea tunnels. In this way, non-earthquake-related high-frequency noise can be effectively filtered out to ensure the accuracy and reliability of the analysis results, thereby enhancing the design safety of undersea tunnels and reducing the risks that may be caused by future seismic events. It should be noted that in earthquake engineering and structural response analysis, it is crucial to accurately calculate the maximum acceleration and effective acceleration. These two parameters help determine the intensity of seismic motion and the possible impact on buildings or structures, thereby providing key data for designing safer and more earthquake-resistant structures. It is the maximum absolute value of acceleration recorded in the earthquake vibration signal. This value reflects the strongest moment of earthquake motion and is a direct indicator for assessing the structural bearing capacity under extreme conditions. By integrating the square of the earthquake acceleration signal and averaging it over the entire earthquake duration, a measure of the energy content of the ground motion is provided, reflecting the total amount of energy during the entire earthquake process.

[0085] Therefore, the method of collecting marine earthquake vibration data and analyzing its time-frequency characteristics to determine the maximum acceleration and effective acceleration is as follows:

[0086] Collect sea area seismic vibration data from seismic monitoring stations, ocean sensors or historical seismic databases, use a low-pass filter to remove high-frequency noise, retain effective seismic signals, and use the short-time Fourier transform formula to process the sea area seismic vibration data. The formula is:

[0087] ;

[0088] in, Indicates at time and frequency The short-time Fourier transform result under the condition of The spectrum information of all signals on Indicates the input marine earthquake vibration signal at time The value of represents a window function, represents the complex exponential function, represents the imaginary unit, represents the angular frequency of the signal, Indicates at time The integral on Indicates time delay;

[0089] By using short-time Fourier transform to perform time-frequency analysis on seismic data, the energy distribution and change trend of the signal at different time points and frequencies are obtained, and the maximum acceleration and effective acceleration of seismic vibration are extracted. By simulating the seismic response of the tunnel under different seismic input conditions, the vibration mode that can cause the maximum structural damage is selected, that is, the most unfavorable seismic vibration input parameter. The formula is:

[0090] ;

[0091] ;

[0092] in, Indicates The maximum acceleration of each part, that is, the maximum absolute value of acceleration in the earthquake vibration signal, Indicates The earthquake vibration signal at each location in time The acceleration under Indicates The effective acceleration of each part, Represents the total duration of the seismic signal; in the above formula, It is time series data, representing the intensity of earthquake vibrations at a specific time; is a window function used to The choice of window function determines the trade-off between time resolution and frequency resolution of the analysis. is a complex exponential function, where Represents the base of natural time, represents the imaginary unit. This expression describes the The oscillator below is used to convert the signal from the time domain to the frequency domain.

[0093] It should be noted that the quasi-static experiment simulates the dynamic impact of an earthquake by applying an equivalent static load. This method can effectively simulate the impact of seismic forces on tunnel structures. By calculating static loads, the dynamic impact of earthquakes can be converted into static problems that are easier to analyze and design. Different parts of a tunnel may have different masses and structural characteristics due to different designs, materials or structures. Calculating the impact stress of each part and accurately calculating the specific impact stress of each part are crucial to understanding which parts are most vulnerable and require special reinforcement.

[0094] Therefore, it is necessary to conduct a quasi-static test on the submarine tunnel to calculate the impact stress of the earthquake on various parts of the tunnel. The method is based on:

[0095] By applying an equivalent static load to simulate the dynamic impact of the earthquake on the tunnel structure, the inertial force generated by the earthquake vibration is converted into a static load. The maximum acceleration and effective acceleration obtained by calculation are used as earthquake input parameters to calculate the equivalent static load. The formula is as follows:

[0096] ;

[0097] in, represents the equivalent static load, Indicates the overall quality of the tunnel;

[0098] In practical application calculations, different parts of the tunnel have different masses and accelerations. The equivalent static loads of various parts of the tunnel are calculated using a general formula. The impact stresses of various parts of the tunnel are calculated based on the equivalent static loads of various parts of the tunnel calculated and the force-bearing areas of various parts of the tunnel. The formula used is:

[0099] ;

[0100] ;

[0101] in, Indicates the tunnel The equivalent static load of each part, Indicates the tunnel The quality of each part, , Respectively represent the tunnel The maximum acceleration and effective acceleration of each part, Indicates the tunnel Impact stress at each part, Indicates the tunnel The force-bearing area of ​​each part, Indicates the index of different parts in the tunnel.

[0102] It should be noted that by calculating the maximum impact stress ratio of each part, the maximum stress that the entire tunnel structure can withstand when facing extreme seismic loads can be determined. This seismic stress limit not only guides the design and construction of the tunnel to ensure that all parts can operate at a safe stress level, but also helps to optimize material use and cost-effectiveness, while ensuring that when an actual earthquake occurs, the key parts of the tunnel will not be damaged due to exceeding the stress limit, thereby ensuring the safety of personnel and the long-term stability of the structure.

[0103] Therefore, it is necessary to comprehensively consider the impact stresses at various parts of the tunnel to generate the seismic stress limit value, based on the following formula:

[0104] ;

[0105] in, represents the seismic stress limit, Indicates the number of collection locations in the tunnel.

[0106] It should be noted that in earthquake engineering, the elastoplastic seismic response analysis of tunnels is extremely important because this analysis can accurately predict and evaluate the structural response and safety status of tunnels under actual earthquakes. By using the finite element method to simulate the dynamic behavior of tunnel structures under seismic loads, it is not only possible to evaluate the performance of tunnels under normal use conditions, but also to predict stress and deformation under extreme conditions. In the elastic stage and the plastic stage after yielding, the calculation of shear stress is extremely critical to determine the safety margin of structural elements and avoid structural damage. In addition, this analysis also helps the design team select appropriate materials and construction techniques to ensure that the tunnel can maintain its function and structural integrity under different earthquake intensities, and engineers can understand and predict the shear stress that various parts of the tunnel may suffer in an earthquake, so as to carry out more accurate design and reinforcement.

[0107] Therefore, it is necessary to calculate the shear stress of the tunnel caused by earthquake based on the elastic-plastic seismic response analysis of the tunnel. The method is as follows:

[0108] By considering the elastic and plastic deformation behaviors of the material, simulating the response of the tunnel under seismic load, the finite element method is used for modeling and analysis, and a three-dimensional geometric model of the tunnel is established. The material property data of the tunnel structure and the surrounding soil are collected. The property data include elastic modulus, Poisson's ratio, yield strength and plastic hardening modulus. The three-dimensional geometric model is divided into finite element units, and the triangular unit is selected as the finite element unit type. The shear strain is calculated by the node displacement, and the shear modulus is calculated by the elastic modulus and Poisson's ratio. The formula is as follows:

[0109] ;

[0110] ;

[0111] in, , Respectively represent Shear force and shear modulus at each part, , Respectively represent The node in the Horizontal and The vertical displacement, Indicates The elastic modulus of the material at each part, Indicates Poisson's ratio of the material in each part;

[0112] When the shear force exceeds the material yield, the shear force needs to consider the influence of yield strength and plastic hardening modulus. The shear stress of each triangular unit is calculated based on the comprehensive shear modulus and shear force. The formula is:

[0113] ;

[0114] in, Indicates The shear stress at each collection site, Indicates The shear modulus of the collected parts, represents the shear strain when the material yields, represents the yield strength of the material, Represents the plastic hardening modulus of the material.

[0115] It should be noted that by calculating the fatigue damage of each finite element unit and accumulating it, engineers can predict the maximum number of stress cycles that the structure can withstand during its lifetime. This helps to determine the safety margin of the structure and ensure that the structure does not suffer unexpected fatigue damage under extreme loads such as earthquakes. In addition, the Miner damage accumulation algorithm is used to perform fatigue limit analysis on tunnels and other structures, which can not only ensure public safety, but also provide support for project management at the economic and operational levels.

[0116] Therefore, the shear stress at each location is combined to generate the material fatigue limit, based on the following method:

[0117] The Miner damage accumulation algorithm is used to calculate the material fatigue limit. For each finite element, the number of stress cycles under earthquake action is calculated. According to the Miner damage accumulation method, the damage caused by a single stress cycle is first calculated, and then the damage of all finite elements is accumulated. The total damage is the material fatigue limit of a single part. The formula is:

[0118] ;

[0119] ;

[0120] in, Indicated in The first part The damage caused by the stress cycle Indicated in The first part The shear stress of a stress cycle, Indicated in The material fatigue limit of each part, represents the index of the damage cycle, represents the total number of injury cycles;

[0121] The material fatigue limit of the tunnel is generated by combining the material fatigue limit of each individual part, based on the following formula:

[0122] ;

[0123] in, Represents the material fatigue limit of the tunnel.

[0124] It should be noted that the seismic performance and seismic margin calculations of tunnels are crucial to assessing their stability and safety during earthquakes. They help engineers quantify the performance of tunnels under the influence of earthquakes and guide appropriate design and reinforcement measures. Such calculations not only affect engineering design and emergency preparedness, but also have great significance for protecting public safety and investment, ensuring the continued operation of transportation infrastructure in emergencies, which is particularly important in earthquake-prone areas.

[0125] Therefore, it is necessary to calculate the seismic performance and seismic margin of the current tunnel, based on the following formula:

[0126] ;

[0127] ;

[0128] in, , They represent seismic performance and seismic margin respectively. Indicates the pressure of the tunnel under the current earthquake, represents the equivalent static load, It represents the ultimate bearing capacity during design. It indicates the actual bearing capacity achieved under earthquake action.

[0129] It should be noted that the calculated deformation limit provides a quantitative standard to evaluate the maximum safe deformation that a tunnel may reach in an actual earthquake. This standard not only helps guide the design and reinforcement of tunnels to ensure that they can maintain structural safety and functional integrity under earthquakes exceeding conventional design parameters, but also has great practical significance for improving disaster response efficiency and protecting people's lives and property.

[0130] Therefore, it is necessary to use the calculated seismic performance and seismic margin to generate the seismic deformation limit value, based on the formula:

[0131] ;

[0132] in, Indicates the seismic deformation limit.

[0133] It should be noted that the degree of damage to the tunnel is determined by comparing the earthquake damage index with the preset severe damage threshold, thereby providing a quantitative, performance-based damage assessment. When the damage index does not exceed the threshold, the tunnel is considered to be not seriously damaged and may not require emergency repairs or can continue to be used safely. When the damage index exceeds the threshold, it means that the tunnel may have suffered serious damage and immediate reinforcement measures or repair work are required.

[0134] Therefore, it is necessary to comprehensively generate the seismic damage index and establish the earthquake damage index of the undersea tunnel. The index is compared with the damage index to determine the severity of the damage. The formula is as follows:

[0135] ;

[0136] ;

[0137] in, represents the earthquake damage index of the submarine tunnel, represents the material fatigue limit, represents the seismic deformation limit, represents the seismic stress limit, Indicates the logical value of whether the damage is serious. When , it means that the seismic damage index does not exceed the earthquake damage index of the submarine tunnel, and the damage is not serious; when When the earthquake damage index exceeds the earthquake damage index of the submarine tunnel, the damage is serious. Indicates damage indicator.

[0138] See also Figure 2 The present invention further provides a submarine tunnel earthquake damage performance calculation system, the performance damage calculation system is used to execute the above-mentioned submarine tunnel earthquake damage performance calculation method, comprising:

[0139] A seismic signal acquisition and time-frequency analysis module, which is used to set multiple acquisition locations in the submarine tunnel, collect sea area seismic vibration signals and analyze their time-frequency characteristics to determine the maximum acceleration and effective acceleration;

[0140] A quasi-static experiment and impact stress calculation module, which is used to perform a quasi-static experiment on the submarine tunnel according to the calculated maximum acceleration and effective acceleration, calculate the impact stress of the earthquake on various parts of the tunnel, and generate a seismic stress limit value based on the impact stress of various parts of the tunnel;

[0141] An elastic-plastic earthquake response analysis module, which is used to analyze the elastic-plastic earthquake response of the tunnel, calculate the shear stress of the earthquake on each part of the tunnel, and generate the material fatigue limit value by integrating the shear stress of each part;

[0142] A seismic performance and margin assessment module, wherein the seismic performance and margin assessment module calculates the seismic performance and seismic margin of the current tunnel based on a comprehensive analysis of the submarine tunnel, and generates a seismic deformation limit value using the calculated seismic performance and seismic margin;

[0143] The seismic damage index generation and evaluation module is used to use the calculated seismic stress limit, material fatigue limit and seismic deformation limit to comprehensively generate a seismic damage index, establish an undersea tunnel earthquake damage index, compare the index with the damage index, and judge the severity of the damage.

[0144] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0145] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0146] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0147] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A method for calculating the earthquake damage performance of a submarine tunnel, characterized in that: The specific steps include: Step 1: Set up multiple collection locations in the submarine tunnel to collect marine earthquake vibration signals and analyze their time-frequency characteristics to determine the maximum acceleration and effective acceleration; Step 2: Based on the calculated maximum acceleration and effective acceleration, a quasi-static test is conducted on the submarine tunnel to calculate the impact stress of the earthquake on various parts of the tunnel, and the seismic stress limit is generated by integrating the impact stress of various parts of the tunnel; Step 3: Analyze the elastic-plastic earthquake response of the tunnel, calculate the shear stress of the earthquake on each part of the tunnel, and generate the material fatigue limit value by integrating the shear stress of each part; Step 4: Based on a comprehensive analysis of the submarine tunnel, the seismic performance and seismic margin of the current tunnel are calculated, and the seismic deformation limit is generated using the calculated seismic performance and seismic margin; Step 5: Using the calculated seismic stress limit, material fatigue limit and seismic deformation limit, a seismic damage index is comprehensively generated, and an undersea tunnel earthquake damage index is established. The index is compared with the damage index to determine the severity of the damage.

2. The method for calculating earthquake damage performance of a submarine tunnel according to claim 1, characterized in that: Collect sea area earthquake vibration data and analyze its time-frequency characteristics to determine the maximum acceleration and effective acceleration. The method is based on: Collect sea area seismic vibration data from seismic monitoring stations, ocean sensors or historical seismic databases, use a low-pass filter to remove high-frequency noise, retain effective seismic signals, and use the short-time Fourier transform formula to process the sea area seismic vibration data. The formula is: ； in, Indicates at time and frequency The short-time Fourier transform result under the condition of The spectrum information of all signals on Indicates the input marine earthquake vibration signal at time The value of represents a window function, represents the complex exponential function, represents the imaginary unit, represents the angular frequency of the signal, Indicates at time The integral on Indicates time delay; By using short-time Fourier transform to perform time-frequency analysis on seismic data, the energy distribution and change trend of the signal at different time points and frequencies are obtained, and the maximum acceleration and effective acceleration of seismic vibration are extracted. By simulating the seismic response of the tunnel under different seismic input conditions, the vibration mode that can cause the maximum structural damage is selected, that is, the most unfavorable seismic vibration input parameter. The formula is: ； ； in, Indicates The maximum acceleration of each part, that is, the maximum absolute value of acceleration in the earthquake vibration signal, Indicates The earthquake vibration signal at each location in time The acceleration under Indicates The effective acceleration of each part, Represents the total duration of the seismic signal.

3. A method for calculating earthquake damage performance of a submarine tunnel according to claim 2, characterized in that: A quasi-static test was conducted on the submarine tunnel to calculate the impact stress of the earthquake on various parts of the tunnel. The method used is: By applying an equivalent static load to simulate the dynamic impact of the earthquake on the tunnel structure, the inertial force generated by the earthquake vibration is converted into a static load. The maximum acceleration and effective acceleration obtained by calculation are used as earthquake input parameters to calculate the equivalent static load. The formula is as follows: ； in, represents the equivalent static load, Indicates the overall quality of the tunnel; In practical application calculations, different parts of the tunnel have different masses and accelerations. The equivalent static loads of various parts of the tunnel are calculated using a general formula. The impact stresses of various parts of the tunnel are calculated based on the equivalent static loads of various parts of the tunnel calculated and the force-bearing areas of various parts of the tunnel. The formula used is: ； ； in, Indicates the tunnel The equivalent static load of each part, Indicates the tunnel The quality of each part, , Respectively represent the tunnel The maximum acceleration and effective acceleration of each part, Indicates the tunnel Impact stress at each part, Indicates the tunnel The force-bearing area of ​​each part, Indicates the index of different parts in the tunnel.

4. A method for calculating earthquake damage performance of a submarine tunnel according to claim 3, characterized in that: The impact stress of each part of the tunnel is combined to generate the seismic stress limit value, based on the formula: ； in, represents the seismic stress limit, Indicates the number of collection locations in the tunnel.

5. The method for calculating earthquake damage performance of a submarine tunnel according to claim 1, characterized in that: Based on the analysis of the elastic-plastic seismic response of the tunnel, the shear stress of the earthquake on each part of the tunnel is calculated according to the following method: By considering the elastic and plastic deformation behaviors of the material, simulating the response of the tunnel under seismic load, the finite element method is used for modeling and analysis, and a three-dimensional geometric model of the tunnel is established. The material property data of the tunnel structure and the surrounding soil are collected. The property data include elastic modulus, Poisson's ratio, yield strength and plastic hardening modulus. The three-dimensional geometric model is divided into finite element units, and the triangular unit is selected as the finite element unit type. The shear strain is calculated by the node displacement, and the shear modulus is calculated by the elastic modulus and Poisson's ratio. The formula is as follows: ； ； in, , Respectively represent Shear force and shear modulus at each part, , Respectively represent The node in the Horizontal and The vertical displacement, Indicates The elastic modulus of the material at each part, Indicates Poisson's ratio of the material in each part; When the shear force exceeds the material yield, the shear force needs to consider the influence of yield strength and plastic hardening modulus. The shear stress of each triangular unit is calculated based on the comprehensive shear modulus and shear force. The formula is: ； in, Indicates The shear stress at each collection site, Indicates The shear modulus of the collected parts, represents the shear strain when the material yields, represents the yield strength of the material, Represents the plastic hardening modulus of the material.

6. A method for calculating earthquake damage performance of a submarine tunnel according to claim 4, characterized in that: The shear stress at each location is combined to generate the material fatigue limit, based on the following method: The Miner damage accumulation algorithm is used to calculate the material fatigue limit. For each finite element, the number of stress cycles under earthquake action is calculated. According to the Miner damage accumulation method, the damage caused by a single stress cycle is first calculated, and then the damage of all finite elements is accumulated. The total damage is the material fatigue limit of a single part. The formula is: ； ； in, Indicated in The first part The damage caused by the stress cycle Indicated in The first part The shear stress of a stress cycle, Indicated in The material fatigue limit of each part, represents the index of the damage cycle, represents the total number of injury cycles; The material fatigue limit of the tunnel is generated by combining the material fatigue limit of each individual part, based on the following formula: ； in, Represents the material fatigue limit of the tunnel.

7. The method for calculating earthquake damage performance of a submarine tunnel according to claim 1, characterized in that: The formula for calculating the seismic performance and seismic margin of the current tunnel is: ； ； in, , They represent seismic performance and seismic margin respectively. Indicates the pressure of the tunnel under the current earthquake, represents the equivalent static load, It represents the ultimate bearing capacity during design. It indicates the actual bearing capacity achieved under earthquake action.

8. A method for calculating earthquake damage performance of a submarine tunnel according to claim 7, characterized in that: The seismic performance and seismic margin calculated above are used to generate the seismic deformation limit value, based on the formula: ； in, Indicates the seismic deformation limit.

9. The method for calculating earthquake damage performance of a submarine tunnel according to claim 1, characterized in that: The earthquake damage index is comprehensively generated, and the earthquake damage index of the submarine tunnel is established. The index is compared with the damage index to determine the severity of the damage. The formula is as follows: ； ； in, represents the earthquake damage index of the submarine tunnel, represents the material fatigue limit, represents the seismic deformation limit, represents the seismic stress limit, Indicates the logical value of whether the damage is serious. When , it means that the seismic damage index does not exceed the earthquake damage index of the submarine tunnel, and the damage is not serious; when When the earthquake damage index exceeds the earthquake damage index of the submarine tunnel, the damage is serious. Indicates damage indicator.

10. A system for calculating earthquake damage performance of a submarine tunnel, the system for calculating earthquake damage performance of a submarine tunnel being used to execute the method for calculating earthquake damage performance of a submarine tunnel according to any one of claims 1 to 9, comprising: A seismic signal acquisition and time-frequency analysis module, which is used to set multiple acquisition locations in the submarine tunnel, collect sea area seismic vibration signals and analyze their time-frequency characteristics to determine the maximum acceleration and effective acceleration; A quasi-static experiment and impact stress calculation module, which is used to perform a quasi-static experiment on the submarine tunnel according to the calculated maximum acceleration and effective acceleration, calculate the impact stress of the earthquake on various parts of the tunnel, and generate a seismic stress limit value based on the impact stress of various parts of the tunnel; An elastic-plastic earthquake response analysis module, which is used to analyze the elastic-plastic earthquake response of the tunnel, calculate the shear stress of the earthquake on each part of the tunnel, and generate the material fatigue limit value by integrating the shear stress of each part; A seismic performance and margin assessment module, wherein the seismic performance and margin assessment module calculates the seismic performance and seismic margin of the current tunnel based on a comprehensive analysis of the submarine tunnel, and generates a seismic deformation limit value using the calculated seismic performance and seismic margin; The seismic damage index generation and evaluation module is used to use the calculated seismic stress limit, material fatigue limit and seismic deformation limit to comprehensively generate a seismic damage index, establish an undersea tunnel earthquake damage index, compare the index with the damage index, and judge the severity of the damage.

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