Equivalent storm method for evaluating elastic-plastic response of structure under rare storm

Abstract

The invention relates to an equivalent storm method for evaluating the elastoplastic response of a structure under a rare storm, and the method is based on the criterion that the elastoplastic response of the equivalent storm to the structure is the same as the elastoplastic response of the actual storm to the structure. Various parameters of an actual storm process are simplified into two parameters of maximum average wind speed (recorded as Umax) and equivalent duration (recorded as teq) calculated based on structural wind-induced hysteretic energy consumption, wind speed-duration joint probability distribution of the equivalent storm is established and used for determining a rare storm process with a specified long return period, and then structural elastoplastic response under the rare storm is evaluated. Wherein the storm history refers to a time-varying average wind speed time history; the problems that a storm process probability model is difficult to establish due to various storm process parameters at present, the rare storm process cannot be determined from the perspective of probability according to a specified long recurrence period, and the evaluation of the elastic-plastic response of the structure under the rare storm is lack of a scientific load input basis are solved.

Description

Technical Field

[0001] The present 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 Art

[0002] In recent years, building structure wind disasters and significant economic losses caused by extreme storms have occurred frequently, which has prompted extensive research on performance - based wind - resistant design methods at home and abroad, and increased the evaluation of the elastoplastic response of structures under rare storms. The wind - induced elastoplastic response of structures is closely related to the storm process (specifically referring to the time - varying mean wind speed time history in the present invention). Since current domestic and foreign meteorological stations only record storm process data for decades, in order to evaluate the elastoplastic response of structures under rare storms, it is necessary to establish a storm process probability model based on statistical analysis to predict and simulate rare storm processes with long return periods.

[0003] At present, there are some storm process simulation methods at home and abroad, such as monsoon simulation methods based on global climate models and regional climate models, typhoon simulation methods based on typhoon paths and wind field models, etc. Through the existing methods, a large number of storm process samples can be provided for the statistical analysis of storm processes. However, both the storm duration and the mean wind speed at each moment are random variables, and it is necessary to describe the storm process through hundreds of parameters, making it difficult to directly establish a storm process probability model. Furthermore, it is impossible to determine rare storm processes from a probabilistic perspective according to a specified long return period, resulting in a lack of a scientific load input basis for evaluating the elastoplastic response of structures under rare storms.

[0004] Therefore, it is necessary to propose a method for simplifying the actual storm process with numerous parameters into an equivalent storm process described by a few parameters, and to carry out the evaluation of the elastoplastic response of structures under rare storms by establishing an equivalent storm process probability model. Summary of the Invention

[0005] In view of this, in order to solve the problem that it is difficult to establish a storm process probability model due to the numerous parameters of the current storm process, and it is impossible to determine rare storm processes from a probabilistic perspective according to a specified long return period, resulting in a lack of a scientific load input basis for evaluating the elastoplastic response of structures under rare storms, the present invention provides an equivalent storm method for evaluating the elastoplastic response of structures under rare storms.

[0006] To achieve the above - mentioned purpose, the present invention provides the following technical solutions:

[0007] An equivalent storm method for evaluating the elastoplastic response of structures under rare storms, based on the criterion that the elastoplastic responses caused by the equivalent storm and the actual storm to the structure are the same, simplifies the numerous parameters of the actual storm process into the maximum mean wind speed (denoted as U max ) and the equivalent duration (denoted as t eq) Two parameters can simply and conveniently establish the joint probability distribution of wind speed - duration of equivalent storms based on statistical analysis, which is used to determine the rare storm process with a specified long return period, and then evaluate the elastoplastic response of the structure under rare storms. Here, the storm process refers to the time - varying mean wind speed time history.

[0008] Furthermore, convert the actual storm into an equivalent storm with a constant mean wind speed equal to the maximum mean wind speed (U max ) of the actual storm. The duration of the equivalent storm is defined as the equivalent duration (t eq ).

[0009] Furthermore, based on the calculation of the wind - induced hysteretic energy dissipation of the structure, determine the equivalent duration (t eq ) to make the elastoplastic responses of the equivalent storm and the actual storm on the structure the same, including the following steps:

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

[0011]

[0012] S2. Based on Equation (1), establish the equation for the equality of hysteretic energy dissipation of the structure under the actual storm and the equivalent storm:

[0013]

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

[0015]

[0016] A large number of studies at home and abroad have shown that due to the non - zero mean wind load and the large proportion of the mean wind in the total wind load, the structure often has the characteristic of unidirectional yielding under the action of the wind load in the along - wind direction. There is a good correlation between the hysteretic energy dissipation and the commonly used elastoplastic response parameters of the structure, such as peak displacement, cumulative plastic deformation, and residual plastic deformation. Therefore, the calculation method of t eq proposed in the present invention can make the relevant indexes such as hysteretic energy dissipation, peak displacement, cumulative plastic deformation, and residual plastic deformation of the structure equal under the action of the actual storm and the equivalent storm.

[0017] Furthermore, the specific processing process of t eq is as follows:

[0018] S31. Divide the actual storm into n sub - storms with a duration of t 0 each. Calculate the mean wind speed U of the storm in the time period from (i - 1)t 0 to it 0 in sequence from i = 1 to i = n.i , where t 0 ranges from 5 min to 60 min and is determined according to the stationarity of the measured wind data at the building site;

[0019] S32. Calculate the critical average wind speed at the first yield of the structure as U d :

[0020]

[0021] In the formula, U w is the smaller average wind speed that will not cause the structure to yield; σ y is the material yield stress; σ max is the maximum stress sample value of the structure under the action of a stationary wind load with an average wind speed of U 0 and a duration of t 0 ; is the sample mean of σ max ; for a structure dominated by wind load, the design basic wind speed is taken as U d .

[0022] S33. Calculate the cut-off wind speed U 0 from i = 1 to i = n in sequence according to the following formula for the time period from (i - 1)t 0 to it tri , which is used to cut off the storm segment where the increase in U d caused by the material strengthening effect under the action of the previous storm segment will not cause plastic behavior of the structure:

[0023]

[0024] In the formula, is a constant value, representing the ratio of U tri to U max,p , which is related to the power spectrum of the fluctuating wind speed at the structure site and is calculated according to the following formula:

[0025]

[0026] In the formula, P[·] is the probability; X(U) is a random variable representing the maximum instantaneous wind speed of a stationary wind with an average wind speed of U and a duration of t 0 ; U max,p = max[U 1 , U 2 , …, U i-1 ; p s is 95%.

[0027] S34. For a specific structure, it is relatively easy to establish the functional relationship F between the mean wind load and the mean wind speed according to existing wind load theories, wind tunnel experiments, building load codes, etc. mean(U) and the functional relationships of the power spectrum of pulsating wind loads with frequency and mean wind speed S p (ω, U).

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

[0029] Furthermore, the prediction of rare storm histories based on the statistical analysis of equivalent storm dual parameters includes the following steps:

[0030] S4. Storm data preparation. To conduct reliable statistical analysis of the equivalent storm U max -t eq , a large number of storm history samples are required. Since current weather stations only record decades of measured data, in addition to the measured data, a large storm history database needs to be obtained through numerical simulation methods based on physical models.

[0031] S5. Calculate the equivalent storm dual parameters. Convert the actual storm into an equivalent storm described by dual parameters. Extract the maximum mean wind speed U from each actual storm history max , and calculate the equivalent duration t according to Equation (3) eq ;

[0032] S6. Statistically analyze and fit the marginal probability distributions of U max , t eq respectively;

[0033] S7. Establish a joint probability distribution model of U max -t eq . Based on the joint probability distribution model of U max -t eq , the dual parameters (U max , t eq ) of the equivalent storm can be determined according to the specified long return period (such as 3000 years), and further generate the equivalent storm history for the evaluation of the elastoplastic response of structures under rare storms.

[0034] Furthermore, the numerical simulation methods based on physical models in step S4 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.

[0035] Furthermore, in step S7, a joint probability distribution model of U max -t eq is established through the Copula method.

[0036] The application of this equivalent storm method for evaluating the elastoplastic response of structures under rare storms is applicable to buildings and structures dominated by the first vibration mode and 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, and the instructions are executed by the at least one processor to enable the at least one processor to execute the above equivalent storm method.

[0038] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it can implement the above equivalent storm method.

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

[0040] 1. An equivalent storm method for evaluating the elastoplastic response of a structure under rare storms disclosed by the present invention simplifies the actual storm process with numerous parameters into an equivalent storm process described by two parameters, namely the maximum average wind speed and the equivalent duration, and the elastoplastic responses caused by the actual storm and the equivalent storm to the structure are the same. By establishing a probability model of the equivalent storm process, it can provide a scientific load input basis for evaluating the elastoplastic response of a structure under rare storms. The processing process of the present invention is simple, efficient, and convenient for engineers to use.

[0041] 2. An equivalent storm method for evaluating the elastoplastic response of a structure under rare storms disclosed by the present invention proposes a t eq calculation method that can make the hysteretic energy dissipation, peak displacement, cumulative plastic deformation, and residual plastic deformation of the structure under the action of the actual storm and the equivalent storm equal. The key evaluation indexes of the elastoplastic response of the structure under the action of the equivalent storm, namely the peak displacement and the expected value of the residual plastic deformation, are in good agreement with the results under the action of the actual storm, and the accuracy is above 90%.

[0042] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent description, and to some extent, they will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0044] Figure 1 is the basic principle diagram of the equivalent storm method for evaluating the elastoplastic response of a structure under rare storms of the present invention;

[0045] Figure 2 is the statistical analysis flow chart of the equivalent storm method for evaluating the elastoplastic response of a structure under rare storms of the present invention;

[0046] Figure 3 It is the statistical analysis flow chart of simulating typhoon wind speed time history in the embodiment of the present invention;

[0047] Figure 4 It is the historical typhoon path map that has an impact on the site in the embodiment of the present invention;

[0048] Figure 5 It is the single typhoon U max Probability density distribution map in the embodiment of the present invention;

[0049] Figure 6 It is the typhoon U obtained in the embodiment of the present invention max Hazard curve graph;

[0050] Figure 7 It is the single typhoon t eq Probability density distribution map in the embodiment of the present invention;

[0051] Figure 8 It is the typhoon t obtained in the embodiment of the present invention eq Hazard curve graph;

[0052] Figure 9 It is the U in the embodiment of the present invention max -t eq Joint probability distribution map;

[0053] Figure 10 It is the peak displacement expected value graph in the embodiment of the present invention;

[0054] Figure 11 It is the residual plastic deformation expected value graph in the embodiment of the present invention. Specific implementation manners

[0055] The following illustrates the implementation manners of the present invention through specific specific examples. Those skilled in the art can easily understand the 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 different specific implementation manners. 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 by the present invention is as Figure 1 shown. Based on the criterion that the elastoplastic responses caused by the equivalent storm and the actual storm to the structure are the same, the actual storm is converted into an equivalent storm with a constant average wind speed and equal to the maximum average wind speed of the actual storm (denoted as U max ), where the duration of the equivalent storm is defined as the equivalent duration (denoted as t eq ).

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

[0058] The key and core issue of the equivalent storm method lies in how to determine the size of the equivalent duration \(t\) eq so that the elastoplastic responses of the structure under the actual storm and the equivalent storm are the same. The most direct and accurate method is to calculate \(t\) eq through the traditional dynamic time history analysis method (denoted as THA), but for thousands or tens of thousands of storms, the calculation efficiency of the THA method is too low, and it is not practical for engineering applications. Therefore, the present invention proposes an analytical formula for the equivalent duration \(t\) eq based on the calculation of the wind-induced hysteretic energy dissipation of the structure.

[0059] Such as Figure 1 shown in an equivalent storm method for evaluating the elastoplastic response of a structure under a rare storm. Based on the criterion that the elastoplastic responses caused by the equivalent storm and the actual storm to the structure are the same, numerous parameters of the actual storm process are simplified into two parameters: the maximum average wind speed (denoted as \(U\) max ) and the equivalent duration based on hysteretic energy dissipation (denoted as \(t\) eq ). It can simply and conveniently establish the wind speed-duration joint probability distribution of the equivalent storm, be used to determine the rare storm process with a specified long return period, and then evaluate the elastoplastic response of the structure under the rare storm.

[0060] Specifically: Convert the actual storm into an equivalent storm with a constant average wind speed equal to the maximum average wind speed (\(U\) max ) of the actual storm, and the duration of the equivalent storm is defined as the equivalent duration (\(t\) eq ).

[0061] Among them, calculating the equivalent duration (\(t\) eq ) based on the wind-induced hysteretic energy dissipation of the structure to make the elastoplastic responses of the equivalent storm and the actual storm to the structure the same includes the following steps:

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

[0063]

[0064] S2. Based on Equation (1), establish an equation relationship where the hysteretic energy dissipations of the structure under the actual storm and the equivalent storm are equal:

[0065]

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

[0067]

[0068] A large number of studies at home and abroad have shown that since the wind load is a non-zero mean load and the proportion of the mean wind in the total wind load is relatively large, the structure often has the characteristic of unidirectional yield under the action of the wind load in the along-wind direction, and there is a good correlation between the hysteretic energy dissipation and the elastic-plastic response parameters commonly used in engineering, such as the peak displacement, the cumulative plastic deformation, and the residual plastic deformation. Therefore, the t eq calculation method proposed in the present invention can make the hysteretic energy dissipation, the peak displacement, the cumulative plastic deformation, and the residual plastic deformation of the structure under the action of the actual storm and the equivalent storm equal.

[0069] Specifically, the t eq processing process is as follows:

[0070] S31. Divide the actual storm into n sub-storms with a duration of t 0 each, and calculate the average wind speed U 0 ~it 0 of the storm in the time period from i = 1 to i = n in sequence, where t i takes a value in the range of 5 min to 60 min and is determined according to the stationarity of the measured wind data at the building site; 0

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

[0072]

[0073] In the formula, U w is the smaller average wind speed that will not cause the structure to yield; σ y is the material yield stress; σ max is the maximum stress sample value of the structure under the action of a steady wind load with an average wind speed of U 0 and a duration of t 0 ; is the sample average value of σ max ; for the structure dominated by wind load, the design basic wind speed is taken as U d .

[0074] S33. Calculate the cut-off wind speed U 0 ~it 0 in the time period from i = 1 to i = n in sequence according to the following formula, which is used to cut off the U caused by the material strengthening effect under the action of the previous storm segment tri ​d Storm section that will not cause structural plastic behavior after enlargement:

[0075]

[0076] In the formula, is a fixed value, representing U tri The ratio of U max,p and U

[0077]

[0078] In the formula, P[·] is the probability; X(U) is a random variable, representing the maximum instantaneous wind speed of a stationary wind with an average wind speed of U and a duration of t 0 ; U max,p = max[U 1 , U 2 , …, U i-1 ; p s is 95%.

[0079] S34. For a specific structure, according to existing wind load theories, wind tunnel experiments, building load codes, etc., it is relatively easy to establish the functional relationship F mean (U) between the mean wind load and the mean wind speed, as well as the functional relationship S p (ω, U) between the power spectrum of the fluctuating wind load and the frequency and the mean wind speed.

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

[0081] Among them, the evaluation of the elastoplastic response of the structure under rare storms includes the following steps:

[0082] Based on the equivalent storm method, according to the process shown in Figure 2 , statistical analysis of the two parameters of the equivalent storm (the maximum mean wind speed U max , the equivalent duration t eq ) is carried out, and then it can be used to evaluate the elastoplastic response of the structure under rare storms.

[0083] S4. Storm data preparation. To carry out reliable statistical analysis of the equivalent storm U max -t eq , a large number of storm history samples are required. Since the current meteorological stations only record decades of measured data, in addition to the measured data, a large number of storm databases need to be obtained through numerical simulation methods based on physical models, such as typhoon simulations 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 dual parameters, convert the actual storm into an equivalent storm described by dual parameters, and extract the maximum average wind speed U from each actual storm history. max , calculate the equivalent duration t according to Equation (3). eq ;

[0085] S6. Statistically analyze and fit U max , t eq marginal probability distributions respectively;

[0086] S7. Establish a joint probability distribution model of U max - t eq through the Copula method (or other methods). Based on the joint probability distribution model of U max - t eq , the dual parameters (U max , t eq ) of the equivalent storm can be determined according to the specified long return period (such as 3000 years), and further generate the equivalent storm history for the evaluation of the elastoplastic response of the structure under rare storms.

[0087] The application of this equivalent storm method for evaluating the elastoplastic response of the structure under rare storms is applicable to buildings and structures that are dominated by the first vibration 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] Take a coastal city in China as the building site. Based on meteorological data, simulate the typhoon wind speed time history as the database for statistical analysis through the process shown in Figure 3 . Based on the CMA tropical cyclone best track dataset, use the simulated circle method with a radius of 250 km centered on the site's longitude and latitude to extract 168 historical typhoon paths (average annual incidence rate of 2.3) that affected the site from 1949 to 2021 as shown in Figure 4 . Establish a probability model for each key parameter of the typhoon through the extracted historical typhoon meteorological data, and then use the Monte Carlo simulation method to generate virtual typhoons. Solve the wind field using the semi-empirical Yan Meng model to calculate the typhoon wind speed time history at the target site, and a total of 1.9 million typhoon wind speed time histories are simulated.

[0091] In this example, a single-degree-of-freedom structure is taken as an example to show the statistical analysis of the equivalent duration U max - t eq , and illustrate the accuracy of the equivalent storm method. The period of the single-degree-of-freedom structure in this example is 1 s, the damping ratio is 2%, the restoring force model uses a bilinear model with a ratio of the second stiffness to the initial stiffness of 0.1, and the critical average wind speed U d= 47.16 m / s. Assume that the wind load follows the quasi-steady hypothesis, and the power spectrum of the fluctuating wind speed at the site is consistent with the Kaimal spectrum. Then, the relationship between the mean wind load and the mean wind speed is shown in Equation (7), and the relationships between the power spectrum of the fluctuating wind load and the wind speed and frequency are shown in Equation (8) respectively. Substituting Equation (7), (8) and the actual time-varying mean wind speed during the storm into Equation (3) can quickly calculate the equivalent duration t eq .

[0092]

[0093] S p (f) = K(f, U)ρ 2 c P 2 A 2 U 4 t 0 (8)

[0094]

[0095] where ρ is the air density; A is the windward area of the building; c p is the mean wind pressure coefficient; x = zf / U; I is the turbulence intensity; z is the structure height; f = ω / 2π is the frequency, Hz.

[0096] S2, the maximum mean wind speed U max , the equivalent duration t eq marginal probability distribution;

[0097] Single typhoon U max probability density distribution is as Figure 5 shown. The highest goodness of fit is obtained by fitting with the Gamma distribution. Combining with the fact that the annual occurrence times of typhoons follow the Poisson distribution (λ = 2.3), the typhoon U max hazard curve is as Figure 6 shown. The 50-year return period typhoon U max is 36.79 m / s, and the 700-year return period typhoon U max is 47.16 m / s.

[0098] When U max < U d = 47.16 m / s, since the structure always remains elastic under the action of the typhoon, the equivalent duration is 0. In subsequent statistical analysis, only consider the typhoon events with U max > U d . Among the 1.9 million simulated typhoon data, there are 1161 cases with U max > U d . The equivalent duration results calculated by Equation (3) are as Figure 7 , Figure 8 shown.

[0099] Figure 7 For a single typhoon t eq Probability density distribution, the goodness of fit with the Gamma distribution is the highest. Combining the annual occurrence times of typhoons following a Poisson distribution (λ = 2.3) to obtain typhoon t eq The hazard curve is as Figure 8 shown

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

[0101] Figure 9 For U max -t eq Joint probability distribution, and shows the variation curves of the 80th percentile and the expected value of the equivalent duration under different U max Based on the U max -t eq Joint probability distribution model, according to the specified long return period, the two parameters (U max , t eq ) of the equivalent storm can be determined, and further, the equivalent storm history can be generated for the evaluation of the elastoplastic response of the structure under rare storms, which has important engineering application value.

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

[0103] 75 storms with U max >U d were randomly selected from the typhoon data for the accuracy verification of the method of the present invention. Assuming that the storm is a stationary random process with a constant average wind speed within each 10-minute interval, 100 pulsating wind speed samples were simulated for each actual storm and equivalent storm by the harmonic synthesis method, and a total of 15,000 storm load samples were generated based on the quasi-steady assumption. Subsequently, the dynamic time history analysis method was used to calculate the expected values of the responses of the structure under the actual storm and the equivalent storm as Figures 10 - 11 shown. It can be seen from the figure that the key evaluation indicators of the elastoplastic response of the structure under the equivalent storm, the peak displacement and the expected value of the residual plastic deformation, are in good agreement with the results under the actual storm, and the accuracy is above 90%, indicating the accuracy of the method of the present invention.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered by the scope of the claims of the present invention.

Claims

1. An equivalent storm method for evaluating the elastic-plastic response of structures under rare storms, characterized in that: Based on the principle that the elastic-plastic response of the equivalent storm to the actual storm is the same, the various parameters of the actual storm process are simplified to the maximum average wind speed (denoted as U max ) and the equivalent duration (denoted as t eq ) two parameters can simply and conveniently establish the wind speed-duration joint probability distribution of the equivalent storm based on statistical analysis, which is used to determine the rare storm history with a specified long return period, and then evaluate the elastic-plastic response of the structure under rare storms, where the storm history refers to the time-varying average wind speed history.

2. The equivalent storm method according to claim 1, characterized in that: The actual storm is converted to a constant average wind speed and is consistent with the actual storm maximum average wind speed (U max ) is equal to the equivalent storm, and the duration of the equivalent storm is defined as the equivalent duration (t eq ).

3. The equivalent storm method according to claim 1, characterized in that: Calculation of equivalent duration based on wind-induced hysteresis energy dissipation of structures (t eq ) makes the elastic-plastic response of the equivalent storm to the actual storm on the structure the same, including the following steps: S1. Establish the functional relationship between the hysteretic energy dissipation of the single-degree-of-freedom elastoplastic structure and the wind input energy of the elastic structure under the action of the storm, and further deduce the hysteretic energy dissipation of the elastoplastic structure. The calculation formula is as follows: S2. Based on equation (1), an equation is established to equalize the hysteresis energy dissipation of the structure under actual storm and equivalent storm: S3. Get the analytical calculation formula for equivalent duration: .

4. The equivalent storm method as claimed in claim 3, characterized in that: Specific eq The processing process is as follows: S31, divide the actual storm into n sub-storms with a duration of t0, and calculate the average wind speed U of the storm in the time period (i-1) t0 to it0 from i=1 to i=n. i , where t0 is in the range of 5min to 60min, determined based on the stability of measured wind data at the building site; S32, according to the following formula, the critical average wind speed of the structure for the first yield is calculated as U d : Where U w is the minimum average wind speed that will not cause structural yield; σ y is the material yield stress; σ max is the maximum stress sample value of the structure under the steady wind load with an average wind speed of U0 and a duration of t0; is max For structures controlled by wind load, the design basic wind speed is taken as U d ; S33, calculate the cut-off wind speed U in the time period (i-1)t0~it0 from i=1 to i=n in sequence according to the following formula tri , used to cut off the U caused by the material strengthening effect under the action of the previous storm segment d Storm segments that will not cause plastic behavior of the structure after enlargement: In the formula, is a fixed value, representing U tri with U max,p The ratio of is related to the fluctuating wind speed power spectrum of the structure site and is calculated according to the following formula: Where P[·] is the 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 95%; S34. For specific structures, the functional relationship between average wind load and average wind speed can be easily established based on existing wind load theory, wind tunnel experiments, building load specifications, etc. mean (U) and the functional relationship between the power spectrum of the pulsating wind load and the frequency and average wind speed S p (ω,U); S35. Input the time-varying average wind speed of the actual storm into formula (3) to conveniently and quickly calculate the equivalent duration t eq .

5. The equivalent storm method according to claim 4, characterized in that: The prediction of rare storm course based on equivalent storm dual-parameter statistical analysis includes the following steps: S4. Storm data preparation, in order to carry out reliable equivalent storm U max -t eq Statistical analysis requires a large number of storm history samples. Since current meteorological stations only record measured data for a few decades, in addition to measured data, it is also necessary to obtain a large number of storm history databases through numerical simulation methods based on physical models. S5. Calculate the equivalent storm double parameters, convert the actual storm into an equivalent storm described by the double parameters, and extract the maximum average wind speed U from each actual storm history. max , calculate the equivalent duration t according to formula (3) eq ; S6. Count and fit U separately max ,t eq Marginal probability distribution; S7. Establish U max -t eq Joint probability distribution model, based on U max -t eq The joint probability distribution model can determine the dual parameters (U max ,t eq ), and further generate equivalent storm histories for evaluating the elastic-plastic response of structures under rare storms.

6. The equivalent storm method according to claim 5, characterized in that: The numerical simulation methods based on the physical model in step S4 include typhoon simulation based on the simulation circle method and the Yan-Meng wind field model, and monsoon simulation method based on the climate analysis model.

7. The equivalent storm method according to claim 6, characterized in that: Step S7: Establish U by Copula method max -t eq Joint probability distribution model.

8. The application of the equivalent storm method according to any one of claims 1 to 7, characterized in that: The equivalent storm method is applicable to buildings and structures dominated by the first-order vibration mode and equivalent to a single-degree-of-freedom system, such as high-rise buildings and flat roof structures.

9. 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, and the instructions are executed by the at least one processor so that the at least one processor can execute the equivalent storm method as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it can implement the equivalent storm method described in any one of claims 1 to 7.

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