An equivalent storm method for evaluating the elastoplastic response of structures under rare storms.

Abstract

This invention relates to an equivalent storm method for evaluating the elastoplastic response of structures under rare storms. Based on the criterion that the equivalent storm and the actual storm cause the same elastoplastic response to the structure, the numerous parameters of the actual storm process are simplified to the maximum mean wind speed (denoted as ). U max ) and the equivalent duration based on structural wind-induced hysteresis energy dissipation calculation (denoted as ) t eq Two parameters are used to establish the wind speed-duration joint probability distribution of an equivalent storm, which is used to determine the history of a rare storm with a specified long return period, and then to evaluate the elastoplastic response of a structure under a rare storm. The storm history refers to the time history of the time-varying average wind speed. This solves the problem that the large number of storm history parameters makes it difficult to establish a probability model of the storm history, and it is impossible to determine the history of a rare storm from a probabilistic perspective based on a specified long return period, which leads to a lack of scientific load input basis for evaluating the elastoplastic response of a structure under a rare storm.

Description

Technical Field

[0001] This invention belongs to the technical field of performance-based structural wind-resistant design methods, and relates to an equivalent storm method for evaluating the elastoplastic response of structures under rare storms. Background Technology

[0002] In recent years, frequent wind-induced structural accidents and significant economic losses caused by extreme storms have prompted extensive research on performance-based wind-resistant design methods both domestically and internationally, increasing the assessment of structural elastoplastic response under rare storms. The wind-induced elastoplastic response of structures is closely related to storm histories (specifically, time-varying average wind speed histories in this invention). Since current meteorological stations both domestically and internationally only record storm histories spanning a few decades, it is necessary to establish probabilistic storm histories prediction and simulation based on statistical analysis to assess the structural elastoplastic response under rare storms.

[0003] Currently, several storm history simulation methods exist both domestically and internationally, such as monsoon simulation methods based on global and regional climate models, and typhoon simulation methods based on typhoon track and wind field models. These existing methods can provide a large number of storm history samples for statistical analysis. However, storm duration and average wind speed at various times are random variables, requiring hundreds of parameters to describe the storm history. This makes it difficult to directly establish a probabilistic model of the storm history, and consequently, it is impossible to determine the history of rare storms from a probabilistic perspective based on a specified long return period. Consequently, there is a lack of scientific load input basis for assessing the elastoplastic response of structures under rare storms.

[0004] Therefore, it is necessary to propose a method to simplify the actual storm history with numerous parameters into an equivalent storm history described by a few parameters, and to conduct structural elastoplastic response assessment under rare storms by establishing an equivalent storm history probability model. Summary of the Invention

[0005] In view of this, in order to solve the problem that the large number of storm history parameters makes it difficult to establish a storm history probability model and to determine the rare storm history from a probabilistic perspective based on a specified long return period, resulting in a lack of scientific load input basis for evaluating the elastoplastic response of structures under rare storms, this invention provides an equivalent storm method for evaluating the elastoplastic response of structures under rare storms.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An equivalent storm method for evaluating the elastoplastic response of structures under rare storms simplifies the numerous parameters of the actual storm process into the maximum mean wind speed (denoted as U) based on the criterion that the equivalent storm and the actual storm cause the same elastoplastic response to the structure. max ) and the equivalent duration (denoted as t) based on structural wind-induced hysteresis energy dissipation calculation eqTwo parameters can be used to easily and conveniently establish the wind speed-duration joint probability distribution of an equivalent storm based on statistical analysis. This can be used to determine the history of a rare storm with a specified long return period, and then to evaluate the elastoplastic response of a structure under a rare storm. The storm history refers to the time history of the time-varying average wind speed.

[0008] Furthermore, the actual storm is converted to a model where the average wind speed is constant and equal to the maximum average wind speed of the actual storm (U). max An equivalent storm is defined as the equivalent duration (t) of a storm. eq ).

[0009] Furthermore, the equivalent duration (t) is calculated based on the structural wind-induced hysteresis energy dissipation. eq To ensure that the equivalent storm produces the same elastoplastic response to the structure as the actual storm, the following steps are included:

[0010] S1. Establish the functional relationship between the hysteretic energy dissipation of a single-degree-of-freedom elastoplastic structure and the wind input energy of the elastic structure under storm action, and further deduce the hysteretic energy dissipation of the missile's plastic structure. The calculation formula is as follows:

[0011]

[0012] S2. Based on equation (1), establish an equation for equal hysteresis energy dissipation of the structure under actual storms and equivalent storms:

[0013]

[0014] S3. Obtain the analytical calculation formula for equivalent duration:

[0015]

[0016] Numerous studies both domestically and internationally have shown that, due to the non-zero mean wind load and the large proportion of average wind load in the total wind load, structures often exhibit unidirectional yielding characteristics under along-wind loads. Hysteretic energy dissipation shows a strong correlation with commonly used structural elasto-plastic response parameters in engineering, such as peak displacement, cumulative plastic deformation, and residual plastic deformation. Therefore, the t proposed in this invention... eq The calculation method can make the relevant indicators such as hysteretic energy dissipation, peak displacement, cumulative plastic deformation, and residual plastic deformation of the structure equal under the action of actual storms and equivalent storms.

[0017] Furthermore, the specific t eq The processing procedure is as follows:

[0018] S31. Divide the actual storm into n sub-storms, each with a duration of t0. Calculate the average wind speed U of the storm during the time interval (i-1)t0 to it0, sequentially from i=1 to i=n. iThe value of t0 is in the range of 5 min to 60 min, and is determined based on the stability of the measured wind data at the building site.

[0019] S32. Calculate the critical average wind speed for the first yield of the structure using the following formula: U d :

[0020]

[0021] In the formula U w The lowest average wind speed that will not cause structural yielding; σ y σ is the yield stress of the material. max The maximum stress sample value of the structure under a steady wind load with an average wind speed of U0 and a duration of t0; For σ max The sample average; for structures dominated by wind load, the design basic wind speed is taken as U. d .

[0022] S33. Calculate the cutoff wind speed U during the time interval (i-1)t0~it0 sequentially from i=1 to i=n according to the following formula. tri Used to cut off the U-shaped effect caused by the material strengthening effect under the action of the previous storm. d Storm segments that, when enlarged, will not induce structural plastic behavior:

[0023]

[0024] In the formula, As a constant, representing U tri with U max,p The ratio is related to the power spectrum of fluctuating wind speeds at the structural site, and is calculated according to the following formula:

[0025]

[0026] In the formula, P[·] represents probability; X(U) is a random variable, representing the maximum instantaneous wind speed of a steady wind with an average wind speed of U and a duration of t0; U max,p =max[U1,U2,…,U i-1 ]; p s It is 95%.

[0027] S34. For specific structures, based on existing wind load theories, wind tunnel experiments, and building load codes, the functional relationship between average wind load and average wind speed F can be easily established. mean (U) and the functional relationship between the power spectrum of fluctuating wind load and frequency and average wind speed S p (ω,U).

[0028] S35. By inputting the time-varying average wind speed of the actual storm into equation (3), the equivalent duration t can be calculated conveniently and quickly. eq .

[0029] Furthermore, the prediction of rare storm processes based on equivalent storm two-parameter statistical analysis includes the following steps:

[0030] S4. Storm data preparation for conducting reliable equivalent storm U. max -t eq Statistical analysis requires a large number of storm history samples. Since current weather stations only record decades of measured data, in addition to measured data, it is also necessary to obtain a large storm history database through numerical simulation methods based on physical models.

[0031] S5. Calculate the equivalent storm's two parameters, transforming the actual storm into an equivalent storm with two-parameter description, and extract the maximum average wind speed U from each actual storm's history. max The equivalent duration t is calculated according to equation (3). eq ;

[0032] S6. Statistically analyze and fit U respectively. max t eq Marginal probability distribution;

[0033] S7, Establish U max -t eq Joint probability distribution model, based on U max -t eq The joint probability distribution model can determine the two parameters (U) of the equivalent storm based on a specified long return period (e.g., 3000 years). max ,t eq Furthermore, an equivalent storm history is generated for evaluating the elastoplastic response of structures under rare storms.

[0034] Furthermore, step S4, based on physical models, includes typhoon simulation based on the simulation circle method and the Yan-Meng wind field model, and monsoon simulation based on climate analysis models.

[0035] Furthermore, step S7 establishes U using the Copula method. max -t eq Joint probability distribution model.

[0036] This paper describes the application of the equivalent storm method for assessing the elastoplastic response of structures under rare storms. This equivalent storm method is applicable to buildings and structures that are dominated by the first mode and can be equivalent to a single-degree-of-freedom system, such as high-rise buildings and flat roof structures.

[0037] An electronic device includes: at least one processor and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the equivalent storming method described above.

[0038] A computer-readable storage medium storing a computer program that, when executed by a processor, can implement the above-described equivalent storming method.

[0039] The beneficial effects of this invention are as follows:

[0040] 1. The present invention discloses an equivalent storm method for evaluating the elastoplastic response of structures under rare storms. It simplifies the actual storm history with numerous parameters into an equivalent storm history described by two parameters: maximum average wind speed and equivalent duration. Furthermore, the actual storm and the equivalent storm cause the same elastoplastic response to the structure. By establishing a probabilistic model of the equivalent storm history, a scientific load input basis can be provided for evaluating the elastoplastic response of structures under rare storms. The processing of the present invention is simple, efficient, and convenient for engineering designers to use.

[0041] 2. The equivalent storm method for evaluating the elastoplastic response of structures under rare storms disclosed in this invention proposes a t eq The calculation method ensures that the hysteretic energy dissipation, peak displacement, cumulative plastic deformation, and residual plastic deformation of the structure are equal under actual storm and equivalent storm conditions. The expected values ​​of the peak displacement and residual plastic deformation, key evaluation indicators of the structure's elastoplastic response under equivalent storm conditions, agree well with the results under actual storm conditions, with an accuracy of over 90%.

[0042] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0043] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0044] Figure 1 This is a basic schematic diagram of the equivalent storm method for evaluating the elastoplastic response of structures under rare storms, as described in this invention.

[0045] Figure 2 This is a flowchart illustrating the statistical analysis used in this invention to evaluate the elastoplastic response of structures under rare storms.

[0046] Figure 3This is a flowchart of the statistical analysis of the time history of simulated typhoon wind speed in an embodiment of the present invention;

[0047] Figure 4 This is a historical typhoon path map that affects the site according to an embodiment of the present invention;

[0048] Figure 5 This invention relates to a single typhoon U. max Probability density distribution diagram;

[0049] Figure 6 Typhoon U, obtained in an embodiment of the present invention max Risk curve;

[0050] Figure 7 For a single typhoon in an embodiment of the present invention t eq Probability density distribution diagram;

[0051] Figure 8 Typhoon t obtained in an embodiment of the present invention eq Risk curve;

[0052] Figure 9 This is an embodiment of the present invention. max -t eq Joint probability distribution diagram;

[0053] Figure 10 This is a diagram showing the expected peak displacement values ​​according to an embodiment of the present invention.

[0054] Figure 11 This is a diagram showing the expected value of residual plastic deformation in an embodiment of the present invention. Detailed Implementation

[0055] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0056] The basic principle of the equivalent storm method proposed in this invention is as follows: Figure 1 As shown, based on the criterion that the equivalent storm and the actual storm cause the same elastoplastic response to the structure, the actual storm is converted into a storm with a constant mean wind speed and the same as the maximum mean wind speed of the actual storm (denoted as U). max An equivalent storm is defined as the equivalent duration (denoted as t). eq ).

[0057] The equivalent storm method simplifies the numerous parameters of the actual storm process into only two parameters: maximum average wind speed and equivalent duration. By establishing the joint probability distribution of wind speed and duration of the equivalent storm, it can be used to determine the process of rare storms with a specified long return period, and then evaluate the elastoplastic response of structures under rare storms. This has important scientific research and engineering significance. The storm process refers to the time history of the time-varying average wind speed.

[0058] The key and core issue of the equivalent storming method lies in how to determine the equivalent duration t. eq The magnitude of this value ensures that the structure exhibits the same elastoplastic response under both actual and equivalent storm conditions. The most direct and accurate method is to calculate t using traditional dynamic time history analysis (THA). eq However, for storms numbering in the thousands or tens of thousands, the THA method is computationally inefficient and impractical for engineering applications. Therefore, this invention proposes an equivalent duration t based on structural wind-induced hysteresis energy dissipation calculation. eq Analyze the formula.

[0059] like Figure 1 The method presented here is an equivalent storm method for evaluating the elastoplastic response of structures under rare storms. Based on the criterion that the equivalent storm and the actual storm cause the same elastoplastic response to the structure, it simplifies the numerous parameters of the actual storm process to the maximum mean wind speed (denoted as U). max ) and equivalent duration based on hysteresis energy consumption (denoted as t) eq The two parameters can be used to easily and conveniently establish the wind speed-duration joint probability distribution of an equivalent storm, which can be used to determine the course of a rare storm with a specified long return period, and then evaluate the elastoplastic response of the structure under a rare storm.

[0060] Specifically, this involves converting the actual storm into one with a constant average wind speed that is also equal to the maximum average wind speed of the actual storm (U). max An equivalent storm is defined as the equivalent duration (t) of a storm. eq ).

[0061] Among them, the equivalent duration (t) is calculated based on the structural wind-induced hysteresis energy consumption. eq To ensure that the equivalent storm produces the same elastoplastic response to the structure as the actual storm, the following steps are included:

[0062] S1. Establish the functional relationship between the hysteretic energy dissipation of a single-degree-of-freedom elastoplastic structure and the wind input energy of the elastic structure under storm action, and further deduce the hysteretic energy dissipation of the missile's plastic structure. The calculation formula is as follows:

[0063]

[0064] S2. Based on equation (1), establish the equation that the hysteresis energy dissipation of the structure is equal under actual storms and equivalent storms:

[0065]

[0066] S3. Obtain the analytical calculation formula for equivalent duration:

[0067]

[0068] Numerous studies both domestically and internationally have shown that, due to the non-zero mean wind load and the large proportion of average wind load in the total wind load, structures often exhibit unidirectional yielding characteristics under along-wind loads. Hysteretic energy dissipation shows a strong correlation with commonly used structural elasto-plastic response parameters in engineering, such as peak displacement, cumulative plastic deformation, and residual plastic deformation. Therefore, the t proposed in this invention... eq The calculation method can make the hysteretic energy dissipation, peak displacement, cumulative plastic deformation, and residual plastic deformation of the structure equal under the action of actual storms and equivalent storms.

[0069] Specific t eq The processing procedure is as follows:

[0070] S31. Divide the actual storm into n sub-storms, each with a duration of t0. Calculate the average wind speed U of the storm during the time interval (i-1)t0 to it0, sequentially from i=1 to i=n. i The value of t0 is in the range of 5 min to 60 min, and is determined based on the stability of the measured wind data at the building site.

[0071] S32. Calculate the critical average wind speed for the first yield of the structure using the following formula: U d :

[0072]

[0073] In the formula U w The lowest average wind speed that will not cause structural yielding; σ y σ is the yield stress of the material. max The maximum stress sample value of the structure under a steady wind load with an average wind speed of U0 and a duration of t0; For σ max The sample average; for structures dominated by wind load, the design basic wind speed is taken as U. d .

[0074] S33. Calculate the cutoff wind speed U during the time interval (i-1)t0~it0 sequentially from i=1 to i=n according to the following formula. tri Used to cut off the U-shaped effect caused by the material strengthening effect under the action of the previous storm. d Storm segments that, when enlarged, will not induce structural plastic behavior:

[0075]

[0076] In the formula, As a constant, representing U tri with U max,p The ratio is related to the power spectrum of fluctuating wind speeds at the structural site, and is calculated according to the following formula:

[0077]

[0078] In the formula, P[·] represents probability; X(U) is a random variable, representing the maximum instantaneous wind speed of a steady wind with an average wind speed of U and a duration of t0; U max,p =max[U1,U2,…,U i-1 ]; p s It is 95%.

[0079] S34. For specific structures, based on existing wind load theories, wind tunnel experiments, and building load codes, the functional relationship between average wind load and average wind speed F can be easily established. mean (U) and the functional relationship between the power spectrum of fluctuating wind load and frequency and average wind speed S p (ω,U).

[0080] S35. By inputting the time-varying average wind speed of the actual storm into equation (3), the equivalent duration t can be calculated conveniently and quickly. eq .

[0081] The assessment of the elastoplastic response of a structure under a rare storm includes the following steps:

[0082] Based on the equivalent storm method, according to... Figure 2 The process shown demonstrates the equivalent storm's two parameters (maximum average wind speed U). max Equivalent duration t eq Statistical analysis can then be used to assess the elastoplastic response of structures under rare storms.

[0083] S4. Storm data preparation for conducting reliable equivalent storm U. max -t eq Statistical analysis requires a large number of storm history samples. Since current weather stations only record several decades of measured data, in addition to measured data, it is also necessary to obtain a large storm database through numerical simulation methods based on physical models, such as typhoon simulation based on the simulated circle method and the Yan-Meng wind field model, and monsoon simulation methods based on climate analysis models.

[0084] S5. Calculate the equivalent storm's two parameters, transforming the actual storm into an equivalent storm with two-parameter description, and extract the maximum average wind speed U from each actual storm's history. max The equivalent duration t is calculated according to equation (3). eq ;

[0085] S6. Statistically analyze and fit U respectively.max t eq Marginal probability distribution;

[0086] S7. Establish U using the Copula method (or other methods) max -t eq Joint probability distribution model, based on U max -t eq The joint probability distribution model can determine the two parameters (U) of the equivalent storm based on a specified long return period (e.g., 3000 years). max ,t eq Furthermore, an equivalent storm history is generated for evaluating the elastoplastic response of structures under rare storms.

[0087] This paper describes the application of the equivalent storm method for assessing the elastoplastic response of structures under rare storms. This equivalent storm method is applicable to buildings and structures that are dominated by the first mode and can be equivalent to a single-degree-of-freedom system, such as high-rise buildings and flat roof structures.

[0088] Example

[0089] S1. Data preparation;

[0090] Using a coastal city in China as the construction site, and based on meteorological data, through methods such as... Figure 3 The process shown simulates typhoon wind speed time histories as a database for statistical analysis. Based on the CMA tropical cyclone optimal path dataset, a simulated circle method with the station's latitude and longitude as the center and an influence radius of 250 km was used to extract 168 historical typhoon paths (average annual occurrence rate 2.3) that affected the station from 1949 to 2021. Figure 4 As shown, a probabilistic model of key typhoon parameters was established using historical typhoon meteorological data. Then, a Monte Carlo simulation method was used to generate a virtual typhoon. The semi-empirical Yan Meng model was used to solve the wind field, and the typhoon wind speed time history of the target station was calculated. A total of 1.9 million typhoon wind speed time histories were simulated.

[0091] This example uses a single-degree-of-freedom structure to demonstrate the equivalent duration U. max -t eq Statistical analysis is presented, along with an explanation of the accuracy of the equivalent storm method. In this example, the single-degree-of-freedom structure has a period of 1 second, a damping ratio of 2%, and the restoring force model uses a bilinear model with a second stiffness to initial stiffness ratio of 0.1. The first yield critical mean wind speed is U. d = 47.16 m / s. Assuming the wind load follows the quasi-steady assumption, and the fluctuating wind speed power spectrum at the site is consistent with the Kaimal spectrum, the relationship between the average wind load and the average wind speed is shown in equation (7), and the relationship between the fluctuating wind load power spectrum and the wind speed and frequency is shown in equation (8), respectively. Substituting equations (7), (8) and the actual time-varying average wind speed of the storm into equation (3) allows for the rapid calculation of the equivalent duration t. eq .

[0092]

[0093] S p (f)=K(f,U)ρ 2 c P 2 A 2 U 4 t0 (8)

[0094]

[0095] In the formula, ρ is the air density; A is the building's windward area; c p I is the average wind pressure coefficient; x = zf / U; I is the turbulence intensity; z is the structural height; f = ω / 2π is the frequency, Hz.

[0096] S2, maximum average wind speed U max Equivalent duration t eq Marginal probability distribution;

[0097] single typhoon U max probability density distribution such as Figure 5 As shown, the Gamma distribution provides the best fit, and considering that the annual typhoon occurrence number follows a Poisson distribution (λ = 2.3), the typhoon U... max Risk curves such as Figure 6 As shown, Typhoon U, a once-in-50-year event. max Typhoon U, with a wind speed of 36.79 m / s and a return period of 700 years. max It is 47.16 m / s.

[0098] WhenU max d At a speed of 47.16 m / s, the structure remains elastic under the influence of the typhoon, resulting in an equivalent duration of 0. Subsequent statistical analyses will only consider U. max >U d The typhoon event, among the 1.9 million typhoon data points simulated, U max >U d A total of 1161 items were obtained, and the equivalent duration calculated by equation (3) is as follows: Figure 7 , Figure 8 As shown.

[0099] Figure 7 For a single typhoon eq The probability density distribution was best fitted using the Gamma distribution. Combining this with the fact that the annual typhoon occurrence frequency follows a Poisson distribution (λ = 2.3), the typhoon t was obtained. eq Risk curves such as Figure 8 As shown.

[0100] S3, U​max -t eq Joint probability distribution;

[0101] Figure 9 For U max -t eq Joint probability distribution, and shows different U max The curves showing the changes in the 80th quantile and expected value over the equivalent duration. Based on U max -t eq The joint probability distribution model can determine the two parameters (U) of the equivalent storm based on a specified long return period. max ,t eq Furthermore, it can generate equivalent storm histories, which can be used to evaluate the elastoplastic response of structures under rare storms, and has important engineering application value.

[0102] S4, accuracy of the equivalent storm method;

[0103] 75 U-shaped typhoons were randomly selected from the typhoon data. max >U d The storm was used to verify the accuracy of the method of this invention. Assuming the storm is a stationary random process with an average wind speed that does not change over time within each 10-minute interval, 100 fluctuating wind speed samples were simulated for each actual storm and equivalent storm using the harmonic synthesis method. Based on the quasi-steady assumption, a total of 15,000 storm load samples were generated. Subsequently, the expected response values ​​of the structure under the action of the actual storm and the equivalent storm were calculated using dynamic time history analysis. Figures 10-11 As shown in the figure, the peak displacement and expected value of residual plastic deformation, the key evaluation indicators of the structure's elastoplastic response under the equivalent storm, are in good agreement with the results under the actual storm, with an accuracy of over 90%, demonstrating the accuracy of the method of this invention.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An equivalent storm method for evaluating the elastoplastic response of structures under rare storms, characterized in that, Based on the criterion that the equivalent storm and the actual storm cause the same elastoplastic response to the structure, the numerous parameters of the actual storm process are simplified to the maximum average wind speed. Equivalent duration based on structural wind-induced hysteresis energy dissipation calculation Two parameters enable the simple and convenient establishment of the wind speed-duration joint probability distribution of the equivalent storm based on statistical analysis, which is used to determine the history of a rare storm with a specified long return period, and then to evaluate the elastoplastic response of the structure under the rare storm. The storm history refers to the time history of the time-varying average wind speed. Equivalent duration calculated based on structural wind-induced hysteresis energy dissipation. To ensure that the equivalent storm produces the same elastoplastic response to the structure as the actual storm, the following steps are included: S1. Establish the functional relationship between the hysteretic energy dissipation of a single-degree-of-freedom elastoplastic structure and the wind input energy of the elastic structure under storm action, and further deduce the hysteretic energy dissipation of the missile's plastic structure. The calculation formula is as follows: (1) S2. Based on equation (1), establish an equation for equal hysteresis energy dissipation of the structure under actual storms and equivalent storms: (2) S3. Obtain the analytical calculation formula for equivalent duration: (3) For the critical average wind speed at the first yield of the structure, for Cut off wind speed within the specified time period; Specific The processing procedure is as follows: S31, Divide the actual storm into The duration of each segment is Sub-storm, from to Calculate in sequence Average wind speed of the storm during the time period ,in, The value is taken in the range of 5 min to 60 min, and is determined based on the stability of the measured wind data at the building site.

2. The equivalent storm method as described in claim 1, characterized in that, Convert the actual storm to an average wind speed that is constant and equal to the maximum average wind speed of the actual storm. An equivalent storm is defined as the equivalent duration. .

3. The equivalent storm method as described in claim 1, characterized in that, The processing also includes: S32. The critical average wind speed for the first yield of the structure is calculated according to the following formula: : (4) In the formula The lowest average wind speed that will not cause structural yielding; The yield stress of the material; For the structure at an average wind speed of Duration is The maximum stress sample value under steady wind load; for The sample average; for structures primarily controlled by wind load, the design basic wind speed is used as... ; S33, According to the following formula from to Calculate in sequence Cut-off wind speed within the time period Used to cut off the material strengthening effect caused by the previous storm phase. Storm segments that, when enlarged, will not induce structural plastic behavior: (5) In the formula, As a constant, representing and The ratio is related to the power spectrum of fluctuating wind speeds at the structural site, and is calculated according to the following formula: (6) In the formula, For probability; Let be a random variable, representing the average wind speed. Duration is The maximum instantaneous wind speed of a steady wind; ; It is 95%; S34. For specific structures, based on existing wind load theories, wind tunnel experiments, and building load codes, it is relatively easy to establish a functional relationship between average wind load and average wind speed. and the functional relationship between the power spectrum of pulsating wind load and frequency and average wind speed. ; S35. Inputting the time-varying average wind speed of the actual storm into equation (3) allows for convenient and rapid calculation of the equivalent duration. .

4. The equivalent storm method as described in claim 3, characterized in that, The prediction of rare storm courses based on equivalent storm two-parameter statistical analysis includes the following steps: S4. Storm data preparation for conducting reliable equivalent storm simulations. Statistical analysis requires a large number of storm history samples. Since current weather stations only record several decades of measured data, in addition to measured data, it is also necessary to obtain a large storm history database through numerical simulation methods based on physical models. S5. Calculate the equivalent storm's two parameters, transforming the actual storm into an equivalent storm with a two-parameter description, and extract the maximum average wind speed from each actual storm's history. The equivalent duration is calculated according to equation (3). ; S6. Statistically analyze and fit the results. , Marginal probability distribution; S7, Establish Joint probability distribution model, based on The joint probability distribution model can determine the two parameters of the equivalent storm based on a specified long return period. Furthermore, an equivalent storm history is generated for evaluating the elastoplastic response of structures under rare storms.

5. The equivalent storm method as described in claim 4, characterized in that, Step S4: Numerical simulation methods based on physical models include typhoon simulation based on the simulation circle method and the Yan-Meng wind field model, and monsoon simulation methods based on climate analysis models.

6. The equivalent storm method as described in claim 5, characterized in that, Step S7 establishes using the Copula method Joint probability distribution model.

7. The application of the equivalent storming method as described in any one of claims 1 to 6, characterized in that, This equivalent storm method is applicable to buildings and structures that are dominated by the first mode and can be equivalent to a single-degree-of-freedom system.

8. An electronic device, characterized in that, include: At least one processor and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to perform an equivalent storming method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it can implement the equivalent storm method described in any one of claims 1 to 6.

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