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CN-120145681-B - Equivalent storm method for evaluating elastoplastic response of structure under rare storm

CN120145681BCN 120145681 BCN120145681 BCN 120145681BCN-120145681-B

Abstract

The invention relates to an equivalent storm method for evaluating elastoplastic response of a structure under rare storm, which is used for simplifying various parameters of actual storm history into a maximum average wind speed (marked as U max ) and two parameters of equivalent duration (marked as t eq ) based on structural wind hysteresis energy consumption calculation based on the same criteria of elastoplastic response of the structure caused by equivalent storm and actual storm, establishing wind speed-duration joint probability distribution of the equivalent storm, determining the rare storm history with a specified long reproduction period, further evaluating the elastoplastic response of the structure under the rare storm, wherein the storm history refers to a time-varying average wind speed time course, solving the problems that the probability model of the storm history is difficult to be established due to the fact that the storm history cannot be determined from the probability angle according to the specified long reproduction period, and the elastoplastic response of the structure under the rare storm is not evaluated according to the scientific load input basis.

Inventors

  • CHEN BO
  • CHENG HAO

Assignees

  • 重庆大学

Dates

Publication Date
20260505
Application Date
20250307

Claims (9)

  1. 1. An equivalent storm method for evaluating elastoplastic response of structure under rare storm is characterized in that based on the same criterion of elastoplastic response of equivalent storm and actual storm to structure, various parameters of actual storm course are simplified into maximum average wind speed Equivalent duration time based on structural wind-induced hysteresis energy consumption calculation The two parameters can simply and conveniently establish the wind speed-duration joint probability distribution of the equivalent storm based on statistical analysis, and are used for determining the rare storm history of a specified long reappearance period so as to evaluate the elastoplastic response of the structure under the rare storm, wherein the storm history refers to the time-varying average wind speed time course; equivalent duration time based on structural wind-induced hysteresis energy consumption calculation The elastic-plastic response of the equivalent storm to the structure caused by the actual storm is the same, and the method comprises the following steps: s1, establishing a functional relation between the hysteresis energy consumption of the single-degree-of-freedom elastoplastic structure and the wind input energy of the elastic structure under the action of storm, and further deducing the hysteresis energy consumption of the elastoplastic structure, wherein the calculation formula is as follows: (1) s2, establishing an equation with the same hysteresis energy consumption under the actual storm and the equivalent storm based on the formula (1): (2) s3, obtaining an analytic calculation formula of equivalent holding time: (3) is the critical average wind speed of the first yielding of the structure, Is that Cutting off the wind speed in a time period; In particular The treatment process is as follows: S31, dividing the actual storm into The duration of the segments are all Sub-storms of (2) To the point of Sequentially calculating Storm mean wind speed in time period , wherein, The value is in the range of 5min to 60min, and is determined according to the stability of the actually measured wind data of the building site.
  2. 2. The equivalent storm method of claim 1 wherein said converting of said actual storm to an average wind speed which is constant and which is the maximum average wind speed of said actual storm Equal equivalent storm, duration of equivalent storm is defined as equivalent duration 。
  3. 3. The equivalent storm method of claim 1 wherein, The processing procedure also comprises the following steps: S32, calculating the first yield critical average wind speed of the structure as follows : (4) In the middle of Is a small average wind speed that does not cause structural yield; is the material yield stress; Is structurally characterized by the average wind speed of Duration of is Maximum stress sample value under the effect of stable wind load; Is that For the structure with wind load main control, the basic wind speed is designed as ; S33, according to the following formula To the point of Sequentially calculating Cut-off wind speed in time period For intercepting the effects of material strengthening under the action of the preceding storm section Storm section that does not cause structural plastic behavior after enlargement: (5) In the formula, Is of a constant value and represents And (3) with Is related to the structural site fluctuating wind speed power spectrum, calculated according to the following formula: (6) In the formula, Is probability; Is a random variable representing an average wind speed of Duration of is A maximum instantaneous wind speed of the stationary wind; ; 95%; s34, aiming at a specific structure, a functional relation between the average wind load and the average wind speed is easily established according to the existing wind load theory, wind tunnel experiment and building load specification Functional relation of pulsating wind load power spectrum and frequency and average wind speed ; S35, inputting the time-varying average wind speed of the actual storm into the system (3) to conveniently and rapidly calculate equivalent holding time 。
  4. 4. The equivalent storm method of claim 3 wherein said predicting of rare storm histories based on equivalent storm double parameter statistical analysis comprises the steps of: S4, storm data preparation for developing reliable equivalent storm A large number of storm history samples are needed for statistical analysis, and because the current weather station only records actual measurement data for decades, a large number of storm history databases are needed to be obtained through a numerical simulation method based on a physical model besides the actual measurement data; S5, calculating equivalent storm double parameters, converting the actual storm into double-parameter description equivalent storm, and extracting the maximum average wind speed from each actual storm process Calculating equivalent holding time according to formula (3) ; S6, respectively counting and fitting 、 Edge probability distribution; S7, establishing Joint probability distribution model based on Combined probability distribution model, double parameters capable of determining equivalent storm according to specified long reproduction period " And generating equivalent storm history for evaluating elastoplastic response of the structure under rare storm.
  5. 5. The equivalent storm method of claim 4 wherein the numerical simulation method based on the physical model in step S4 is typhoon simulation based on a simulated circle method and a Yan-Meng wind field model, and a monsoon simulation method based on a climate analysis model.
  6. 6. The equivalent storm method of claim 5 wherein step S7 is established by a Copula method And (5) combining a probability distribution model.
  7. 7. The application of the equivalent storm method as claimed in any one of claims 1-6, wherein the equivalent storm method is applicable to buildings and structures with a first order mode of vibration dominant which can be equivalent to a single degree of freedom system.
  8. 8. An electronic device comprising at least one processor and a memory communicatively coupled 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 the equivalent storm method of any of claims 1-6.
  9. 9. A computer readable storage medium storing a computer program, which when executed by a processor is capable of implementing the equivalent storm method of any of claims 1 to 6.

Description

Equivalent storm method for evaluating elastoplastic response of structure under rare storm Technical Field The invention belongs to the technical field of performance-based structural wind resistance design methods, and relates to an equivalent storm method for evaluating elastoplastic response of a structure under rare storms. Background In recent years, wind disaster accidents and great economic losses of building structures caused by extreme storms frequently occur, so that a great amount of performance-based wind resistance design method researches are promoted at home and abroad, and structural elastoplastic response evaluation under rare storms is increased. The structural wind induced elastoplastic response is closely related to storm history (the time course of the time-varying average wind speed is particularly referred to by the invention), and since the current weather stations at home and abroad only record storm history data for decades, in order to evaluate the structural elastoplastic response under rare storm, it is necessary to establish storm history probability model prediction based on statistical analysis and simulate the rare storm history with long recurrence period. At present, there are some storm history simulation methods at home and abroad, such as a monsoon simulation method based on a global climate model and a regional climate model, a typhoon simulation method based on a typhoon path and a wind field model, and the like. A large number of storm history samples can be provided for statistical analysis of storm histories by the existing method, however, storm duration and average wind speed at each moment are random variables, the storm histories are described by hundreds of parameters, a storm histories probability model is difficult to directly establish, and further, the rare storm histories cannot be determined from the probability angle according to a specified long reproduction period, so that the structural elastoplastic response under the rare storm is evaluated and a scientific load input basis is lacked. Therefore, it is necessary to propose a method for simplifying the actual storm history with various parameters into the equivalent storm history described by a few parameters, and develop structural elastoplastic response evaluation under rare storm by establishing an equivalent storm history probability model. Disclosure of Invention In view of the above, the invention provides an equivalent storm method for evaluating the elastoplastic response of a structure under a rare storm in order to solve the problem that the elastoplastic response of the structure under the rare storm lacks scientific load input basis because the storm history cannot be determined from the probability angle according to a specified long reproduction period due to the difficulty in establishing a storm history probability model caused by the plurality of storm history parameters at present. In order to achieve the above purpose, the present invention provides the following technical solutions: an equivalent storm method for evaluating the elastoplastic response of a structure under a rare storm is characterized in that based on the same criterion of the elastoplastic response of the equivalent storm and the actual storm to the structure, various parameters of the actual storm history are simplified into two parameters of maximum average wind speed (marked as U max) and equivalent duration time (marked as t eq) based on structural wind induced hysteresis energy consumption calculation, the wind speed-duration joint probability distribution of the equivalent storm can be simply and conveniently established based on statistical analysis, and the wind speed-duration joint probability distribution is used for determining the rare storm history with a specified long reproduction period so as to evaluate the elastoplastic response of the structure under the rare storm, wherein the storm history refers to the time-varying average wind speed time course. Further, the actual storm is converted into an equivalent storm having an average wind speed constant and 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 holding time (t eq). Further, calculating the equivalent duration based on the structural wind-induced hysteresis energy consumption (t eq) to make the equivalent storm the same as the elastoplastic response caused by the actual storm to the structure, comprising the following steps: s1, establishing a functional relation between the hysteresis energy consumption of the single-degree-of-freedom elastoplastic structure and the wind input energy of the elastic structure under the action of storm, and further deducing the hysteresis energy consumption of the elastoplastic structure, wherein the calculation formula is as follows: s2, establishing an equation with the same hysteresis energy consumption under the a