Method for evaluating large-span bridge under typhoon action

Abstract

The invention discloses a method for evaluating a long-span bridge under the action of typhoon, which is used for solving the defect that the safe operation state of the long-span bridge is difficult to evaluate after the action of typhoon, and comprises the following steps: obtaining original data from a health monitoring platform, and decoding the original data to obtain data before typhoon, in typhoon and after typhoon; main beam vibration analysis and inhaul cable vibration analysis are performed based on the bridge health monitoring data under the typhoon effect, the bridge vibration response condition under the typhoon effect is explored, and a wind-induced vibration analysis report during the typhoon period is formed; and comparing data before and after the typhoon action, analyzing the characteristic change of the bridge structure under the typhoon action, evaluating the safety of the bridge structure after the typhoon action, and forming a bridge detection index comparison analysis report before and after the typhoon action and a bridge safety evaluation report after the typhoon action. The method can achieve the detailed evaluation of the safety of the long-span bridge under the typhoon effect, and provides an effective tool for guaranteeing the safe operation of the long-span bridge after the typhoon effect.

Description

Technical Field

[0001] This invention belongs to the field of bridge health monitoring data analysis and structural assessment, specifically relating to an assessment method for long-span bridges under typhoon conditions. Background Technology

[0002] Typhoons pose a significant threat to the structural safety of long-span bridges. Existing research primarily focuses on long-span highway bridges, with insufficient attention paid to the typhoon response of long-span railway bridges. The unclear impact of typhoons on railway bridges can easily lead to operational accidents. Therefore, the structural assessment of long-span railway bridges under typhoon conditions has become a research hotspot. Post-typhoon assessment methods for long-span railway bridges provide an effective means for evaluating these bridges after typhoon impact. Summary of the Invention

[0003] This invention is proposed to address the problems existing in the prior art, and its purpose is to provide an evaluation method for long-span bridges under typhoon conditions.

[0004] The technical solution of this invention is: a method for evaluating long-span bridges under typhoon conditions, comprising the following steps: A. Obtain and decode the raw data from the bridge health monitoring platform to obtain monitoring data before, during, and after the typhoon; B. Select data from the typhoon to perform vibration analysis on the main beam. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis. C. Select data from the typhoon to conduct vibration analysis on the cables. The analysis includes acceleration analysis, vortex vibration calculation, and amplitude analysis, and generate a report on wind-induced vibration analysis during the typhoon. D. Combining data before and after the typhoon, analyze the extreme value changes of multiple indicators of bridge structure under the action of the typhoon, extract the extreme values ​​before and after the typhoon and conduct comparative analysis, and compare the extreme values ​​with the safety threshold to determine the structural safety status. E. By combining data before and after the typhoon, analyze the changing patterns of multiple indicators of bridge structure under the influence of the typhoon, and generate a comparative analysis report on bridge inspection indicators before and after the typhoon. F. Combining the wind-induced vibration analysis report during the typhoon and the comparative analysis report of bridge inspection indicators before and after the typhoon, a bridge safety assessment report after the typhoon is formed.

[0005] Furthermore, step A acquires and decodes the raw data from the bridge health monitoring platform to obtain monitoring data before, during, and after the typhoon. The specific process is as follows: First, data transmission and decoding require connection to the health monitoring platform, data transmission, timestamp matching and decoding, and sorting and output of the decoded data; Then, the decoded data before, during, and after the typhoon meet the requirements of consistent time series length and consistent sensor sampling method and frequency.

[0006] Furthermore, step B selects data from the typhoon to perform vibration analysis on the main beam. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis. The specific process is as follows: First, the acceleration analysis of the main beam includes time history curve analysis and Fourier transform spectrum analysis. The Fourier transform formula is as follows: (1) in, For signal spectral density function; Then, the vortex-induced vibration of the main beam was calculated according to the standard formula, and the calculation results for highways and railways were compared. The railway calculation formula is as follows: (2) in, This is the allowable amplitude of vertical vortex-induced vibration. It is the vertical bend fundamental frequency (Hz). It is the vortex vibration mode coefficient. It is the train's operating speed (m / s). It is the length of the main span; Finally, in the amplitude analysis of the main beam, the vertical amplitude at mid-span needs to be obtained by frequency domain integration and compared with the limit value calculated by the standard to assess the safety status of the bridge.

[0007] Furthermore, step C selects data from the typhoon to perform vibration analysis on the cables. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis, generating a wind-induced vibration analysis report during the typhoon. The specific process is as follows: First, the cable acceleration analysis includes time history curve analysis and Fourier transform spectrum analysis. The cable vortex-induced vibration calculation is performed according to the standard formula, and the calculation results for highways and railways are compared. The cable vortex-induced vibration calculation formula is as follows: (3) in, It is the amplitude of vortex vibration (m). It is a Strauhall number. It is a Skruton number. It is the diameter (m) of the stay cable or gantry. It is the standard deviation of the lift coefficient. It is the damping ratio of the stay cable or the suspender. Air density (kg / m³) 3 ), It is the mass per unit length of the stay cable or gantry (kg / m). It is the wind speed (m / s); Then, in the cable amplitude analysis, the mid-span vertical amplitude needs to be obtained by frequency domain integration and compared with the limit value calculated by the standard to assess the safety status of the bridge.

[0008] Furthermore, step D combines data from before and after the typhoon to analyze the extreme value changes of multiple indicators of the bridge structure under the influence of the typhoon, extracts the extreme values ​​before and after the typhoon and compares them, and compares the extreme values ​​with the safety threshold to determine the structural safety status. The specific process is as follows: The extracted extreme values ​​include the maximum, minimum, and range before and after the typhoon; The safety threshold consists of the bridge design calculation value and the limit value specified in the bridge code; The analysis indicators include wind speed, temperature, deflection, beam end displacement, beam end rotation angle, lateral displacement and amplitude, cable force and acceleration.

[0009] Furthermore, step E involves analyzing the patterns of change, including plotting time-history curves and correlation graphs, and analyzing the correlation through linear fitting.

[0010] Furthermore, the analytical indicators in step E include wind speed, temperature, deflection, beam end displacement, beam end rotation angle, lateral displacement and amplitude, cable force, and acceleration.

[0011] Furthermore, the bridge safety assessment report after the typhoon in step F includes two parts: a report on wind-induced vibration during the typhoon and a report on the comparative analysis of bridge inspection indicators before and after the typhoon.

[0012] The beneficial effects of this invention are as follows: This invention can systematically analyze the changes in downwind-induced vibration characteristics before, during, and after a typhoon, aiming to study the structural response and safety assessment of long-span railway bridges under typhoon conditions, filling the current gap in typhoon response research on long-span railway bridges.

[0013] This invention employs methods such as extreme value comparison, time history variation analysis, and correlation testing to analyze the changes in key indicators of bridges during typhoon passage. It uses short-time Fourier transform to analyze the acceleration vibration frequency characteristics of the main beam and cables, and calculates amplitude limits in conjunction with the "Code for Wind-Resistant Design of Railway Bridges". The invention evaluates the wind-induced vibration and key monitoring indicator changes of the bridge structure before, during, and after the typhoon, and focuses on the structural stability and safety redundancy of the bridge.

[0014] This invention is a key step in ensuring the safe operation of bridges. It can effectively analyze the changes in the mechanical properties of bridges before and after typhoons, monitor the structural vibration under the action of typhoons in real time, calculate the structural safety redundancy, and promptly identify and eliminate potential safety hazards in bridge structures, providing decision-making guidance for the maintenance and management of bridges. Attached Figure Description

[0015] Figure 1 This is a diagram illustrating the architecture of a method for evaluating the structure of a long-span bridge under typhoon conditions, as proposed in this invention. Figure 2 This is a time history diagram of the mid-span lateral displacement amplitude of the present invention; Figure 3 This is a time history diagram of the upstream deflection of the bridge in this invention; Figure 4 This is a correlation diagram of beam end displacement before and after the typhoon in this invention; Figure 5 This is the first-order vertical bending spectrum diagram of the main beam after a typhoon in this invention. Detailed Implementation

[0016] The present invention will now be described in detail with reference to the accompanying drawings and embodiments: like Figures 1 to 5 As shown, a method for evaluating long-span bridges under typhoon conditions includes the following steps: A. Obtain and decode the raw data from the bridge health monitoring platform to obtain monitoring data before, during, and after the typhoon; B. Select data from the typhoon to perform vibration analysis on the main beam. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis. C. Select data from the typhoon to conduct vibration analysis on the cables. The analysis includes acceleration analysis, vortex vibration calculation, and amplitude analysis, and generate a report on wind-induced vibration analysis during the typhoon. D. Combining data before and after the typhoon, analyze the extreme value changes of multiple indicators of bridge structure under the action of the typhoon, extract the extreme values ​​before and after the typhoon and conduct comparative analysis, and compare the extreme values ​​with the safety threshold to determine the structural safety status. E. By combining data before and after the typhoon, analyze the changing patterns of multiple indicators of bridge structure under the influence of the typhoon, and generate a comparative analysis report on bridge inspection indicators before and after the typhoon. F. Combining the wind-induced vibration analysis report during the typhoon and the comparative analysis report of bridge inspection indicators before and after the typhoon, a bridge safety assessment report after the typhoon is formed.

[0017] Step A involves acquiring and decoding the raw data from the bridge health monitoring platform to obtain monitoring data before, during, and after the typhoon. The specific process is as follows: First, data transmission and decoding require connection to the health monitoring platform, data transmission, timestamp matching and decoding, and sorting and output of the decoded data; Then, the decoded data before, during, and after the typhoon meet the requirements of consistent time series length and consistent sensor sampling method and frequency.

[0018] Step B involves selecting data from the typhoon and performing vibration analysis on the main beam. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis. The specific process is as follows: First, the acceleration analysis of the main beam includes time history curve analysis and Fourier transform spectrum analysis. The Fourier transform formula is as follows: (1) in, For signal spectral density function; Then, the vortex-induced vibration of the main beam was calculated according to the standard formula, and the calculation results for highways and railways were compared. The railway calculation formula is as follows: (2) in, This is the allowable amplitude of vertical vortex-induced vibration. It is the vertical bend fundamental frequency (Hz). It is the vortex vibration mode coefficient. It is the train's operating speed (m / s). It is the length of the main span; Finally, in the amplitude analysis of the main beam, the vertical amplitude at mid-span needs to be obtained by frequency domain integration and compared with the limit value calculated by the standard to assess the safety status of the bridge.

[0019] Step C involves selecting data from the typhoon and performing vibration analysis on the cables. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis, resulting in a typhoon-induced vibration analysis report. The specific process is as follows: First, the cable acceleration analysis includes time history curve analysis and Fourier transform spectrum analysis. The cable vortex-induced vibration calculation is performed according to the standard formula, and the calculation results for highways and railways are compared. The cable vortex-induced vibration calculation formula is as follows: (3) in, It is the amplitude of vortex vibration (m). It is a Strauhall number. It is a Skruton number. It is the diameter (m) of the stay cable or gantry. It is the standard deviation of the lift coefficient. It is the damping ratio of the stay cable or the suspender. Air density (kg / m³) 3 ), It is the mass per unit length of the stay cable or gantry (kg / m). It is the wind speed (m / s); Then, in the cable amplitude analysis, the mid-span vertical amplitude needs to be obtained by frequency domain integration and compared with the limit value calculated by the standard to assess the safety status of the bridge.

[0020] Step D combines data from before and after the typhoon to analyze the extreme value changes of multiple indicators of the bridge structure under the influence of the typhoon, extracts the extreme values ​​before and after the typhoon and compares them, and compares the extreme values ​​with the safety threshold to determine the structural safety status. The specific process is as follows: The extracted extreme values ​​include the maximum, minimum, and range before and after the typhoon; The safety threshold consists of the bridge design calculation value and the limit value specified in the bridge code; The analysis indicators include wind speed, temperature, deflection, beam end displacement, beam end rotation angle, lateral displacement and amplitude, cable force and acceleration.

[0021] Step E involves analyzing the patterns of change, including plotting time-history curves and correlation graphs, and analyzing the correlation through line fitting.

[0022] The analytical parameters in step E include wind speed, temperature, deflection, beam end displacement, beam end rotation angle, lateral displacement and amplitude, cable force, and acceleration.

[0023] The bridge safety assessment report after the typhoon in step F includes two parts: a report on wind-induced vibration during the typhoon and a report on the comparison and analysis of bridge inspection indicators before and after the typhoon. Example

[0024] A method for evaluating long-span bridges under typhoon conditions includes the following steps: A. Obtain and decode the raw data from the bridge health monitoring platform to obtain monitoring data before, during, and after the typhoon; B. Select data from the typhoon to perform vibration analysis on the main beam. The analysis includes acceleration analysis, vortex-induced vibration calculation, and amplitude analysis. C. Select data from the typhoon to conduct vibration analysis on the cables. The analysis includes acceleration analysis, vortex vibration calculation, and amplitude analysis, and generate a report on wind-induced vibration analysis during the typhoon. D. Combining data before and after the typhoon, analyze the extreme value changes of multiple indicators of bridge structure under the action of the typhoon, extract the extreme values ​​before and after the typhoon and conduct comparative analysis, and compare the extreme values ​​with the safety threshold to determine the structural safety status. E. By combining data before and after the typhoon, analyze the changing patterns of multiple indicators of bridge structure under the influence of the typhoon, and generate a comparative analysis report on bridge inspection indicators before and after the typhoon. F. Combining the wind-induced vibration analysis report during the typhoon and the comparative analysis report of bridge inspection indicators before and after the typhoon, a bridge safety assessment report after the typhoon is formed.

[0025] Specifically, the vibration analysis of the main girder of the long-span railway bridge in step B is crucial for assessing the bridge's stability and safety. It mainly includes three parts: acceleration analysis, vortex-induced vibration calculation, and amplitude analysis, as detailed below: The purpose of main beam acceleration analysis is to assess its vibration characteristics and whether it exceeds the safe vibration range by measuring and analyzing the acceleration response of the main beam under typhoon wind load.

[0026] b11. Data Acquisition and Processing: Data is acquired in real time using an accelerometer and transmitted to the computing platform. Time-domain analysis is performed on the acquired acceleration data, and filtering algorithms are used to remove noise interference, resulting in an accurate acceleration response.

[0027] b12. Frequency Domain Analysis: Perform a Fourier Transform (FFT) on the acceleration data to obtain the spectrum. The Fourier Transform formula is as follows: (1) in, For signal The spectral density function.

[0028] Vortex-induced vibration of the main girder refers to the vibration caused by the shedding of vortices in the main girder of a bridge due to the interaction between wind force and the structural characteristics of the bridge. To assess the vortex-induced vibration effect under typhoon conditions, according to Article 8.1.9 of the "Code for Wind-Resistant Design of Railway Bridges" (QCR9162-2023), the vertical vortex-induced vibration amplitude of the bridge should meet the following requirement: ; (2); in, This is the allowable amplitude of vertical vortex-induced vibration. It is the vertical bend fundamental frequency (Hz). It is the vortex vibration mode coefficient. It is the train's operating speed (m / s). It is the length of the main span.

[0029] Amplitude analysis is used to assess the vibration amplitude of the main beam under typhoon conditions and its impact on structural safety, including the following: b31. The frequency spectrum of acceleration is converted into the frequency spectrum of amplitude using the frequency domain integration method; b32. Perform an inverse Fourier transform on the spectrum of the amplitude to obtain the vertical amplitude at mid-span of the main beam; b33. Compare the measured amplitude with the amplitude calculated by the standard to determine the structural vibration safety status.

[0030] Specifically, in step C, the cables, as crucial load-bearing components of the bridge, are subject to significant vibrations under strong winds such as typhoons. To assess the vibration characteristics of the cables under typhoon conditions and their impact on the overall safety of the bridge, the analysis is conducted in three main parts: acceleration analysis, vortex-induced vibration calculation, and amplitude analysis. The details are as follows: The main role of acceleration analysis in cable vibration analysis is to assess the dynamic response of cables under typhoon wind loads. Accelerometers are used to monitor the cable vibration characteristics and determine whether they exceed safe vibration ranges.

[0031] During typhoons, acceleration data of the cables is collected in real time using accelerometers. The collected data is filtered and denoised to obtain accurate acceleration response data. The cable's spectrum is obtained by performing a Fast Fourier Transform (FFT) on the acceleration data. Cables are susceptible to wind-induced vortex-induced vibration under strong winds, which significantly impacts the structural stability of the cables. According to Article 8.3.2 of the "Code for Wind-Resistant Design of Railway Bridges" (QCR9162-2023), the amplitude of cable vortex-induced vibration should meet the following requirement: (3) in, It is the amplitude of vortex vibration (m). It is a Strauhall number. (5) For cylindrical components, 0.2 is generally used. It is a Skruton number. (6) is the diameter (m) of the stay cable or suspender. This is the standard deviation of the lift coefficient, which is generally taken as 0.45 for cylindrical components. It is the damping ratio of the stay cable or the suspender. Air density (kg / m³) 3 ), It is the mass per unit length of the stay cable or gantry (kg / m). It is the wind speed (m / s).

[0032] Cable amplitude analysis is used to assess whether the vibration amplitude of the cables exceeds safety standards under typhoon conditions, thereby determining the safety of the cables. The cable amplitude is calculated using the frequency domain integration method and compared with the limit values ​​calculated according to regulations to assess the safety status of the bridge.

[0033] Specifically, the extreme values ​​before and after the typhoon in step D are compared and analyzed as follows: Extreme value extraction involves analyzing bridge structural response data before and after a typhoon to extract key extreme value information. This extreme value information effectively reflects the bridge's maximum load-bearing capacity and response characteristics under typhoon conditions. Extreme values ​​include maximum, minimum, and range values ​​before and after the typhoon, while the safety threshold consists of bridge design calculations and bridge code-defined limits. The main extracted indicators include wind speed, temperature, deflection, beam end displacement, beam end rotation angle, lateral displacement and amplitude, cable force, and acceleration.

[0034] Specifically, the analysis of the time-series changes and correlations before and after the typhoon in step E is as follows: Under the influence of typhoons, the response parameters of long-span railway bridges exhibit patterns different from those under normal conditions. To comprehensively understand the changing trends and inherent correlations of the structural responses before and after typhoons, a method of comparing time history patterns, correlation analysis, and fitting was employed. Key indicators included wind speed, temperature, deflection, beam end displacement, beam end rotation angle, lateral displacement and amplitude, cable force, and acceleration, as detailed below: e1. Plot the time history data before and after the typhoon into a curve and conduct comparative analysis. Determine the changes in external factors such as wind speed and temperature before and after the typhoon. By comparing the time history data of bridge deflection, displacement, and rotation angle within the same time period, determine the impact of typhoon wind load on the bridge structure. e2. Correlation scatter plots are used to explore the relationships between different parameters, especially the relationship between typhoon wind speed, temperature, and bridge structural response. By drawing scatter plots, it is possible to visually see whether there are significant linear or nonlinear correlations between variables; e3. Correlation fitting is used to quantitatively analyze the relationships between various factors. By fitting curves, the quantitative relationships between various responses can be evaluated more accurately. This method uses linear fitting. See the mid-span lateral amplitude time history diagram. Figure 2 See the upstream deflection time history diagram. Figure 3 The fitting results are shown in the figure. Figure 4 The spectrum diagram after acceleration data processing is shown below. Figure 5 .

[0035] This invention can systematically analyze the changes in downwind-induced vibration characteristics before, during, and after a typhoon, aiming to study the structural response and safety assessment of long-span railway bridges under typhoon conditions, filling the current gap in typhoon response research on long-span railway bridges.

[0036] This invention employs methods such as extreme value comparison, time history variation analysis, and correlation testing to analyze the changes in key indicators of bridges during typhoon passage. It uses short-time Fourier transform to analyze the acceleration vibration frequency characteristics of the main beam and cables, and calculates amplitude limits in conjunction with the "Code for Wind-Resistant Design of Railway Bridges". The invention evaluates the wind-induced vibration and key monitoring indicator changes of the bridge structure before, during, and after the typhoon, and focuses on the structural stability and safety redundancy of the bridge.

[0037] This invention is a key step in ensuring the safe operation of bridges. It can effectively analyze the changes in the mechanical properties of bridges before and after typhoons, monitor the structural vibration under the action of typhoons in real time, calculate the structural safety redundancy, and promptly identify and eliminate potential safety hazards in bridge structures, providing decision-making guidance for the maintenance and management of bridges.

Claims

1. A method for evaluating a long-span bridge under typhoon action, characterized in that: The method comprises the following steps: A. Obtain the original data of the bridge health monitoring platform and decode to obtain the monitoring data before, during and after the typhoon; B. Select the data during the typhoon, analyze the vibration of the main girder, and the analysis content includes acceleration analysis, vortex vibration calculation and amplitude analysis; C. Select the data during the typhoon, analyze the vibration of the cable, and the analysis content includes acceleration analysis, vortex vibration calculation and amplitude analysis, and form a wind-induced vibration analysis report during the typhoon; D. Combine the data before and after the typhoon, analyze the multi-index extreme value change of the bridge structure under the action of the typhoon, extract the extreme value before and after the action of the typhoon and perform comparative analysis, compare the extreme value with the safety threshold, and judge the safety state of the structure; E. Combine the data before and after the typhoon, analyze the multi-index change law of the bridge structure under the action of the typhoon, and form a bridge detection index comparison analysis report before and after the typhoon; F. Combine the wind-induced vibration analysis report during the typhoon and the bridge detection index comparison analysis report before and after the typhoon to form a bridge safety evaluation report after the typhoon.

2. The method for evaluating long-span bridge under typhoon according to claim 1, wherein: Step A obtains the original data of the bridge health monitoring platform and decodes to obtain the monitoring data before, during and after the typhoon, and the specific process is as follows: First, data transmission and decoding need to be connected with the health monitoring platform, data transmission, time stamp matching and decoding, and sorted output of the decoded data; Then, the decoded data before, during and after the typhoon meet the consistent time sequence length, consistent sensor sampling mode and frequency.

3. The method of claim 1, wherein: Step B selects the data during the typhoon, analyzes the vibration of the main girder, and the analysis content includes acceleration analysis, vortex vibration calculation and amplitude analysis, and the specific process is as follows: First, the acceleration analysis of the main girder includes time history curve analysis and Fourier transform spectrum analysis, and the Fourier transform formula is as follows: （1） wherein is the spectral density function of the signal ​ Then, the vortex vibration calculation of the main girder is calculated according to the specification formula, and the calculation results of highway and railway are compared, and the railway calculation formula is as follows: （2） wherein, is the amplitude allowance value of the vertical vortex vibration, is the vertical bending fundamental frequency (Hz), is the vortex vibration mode shape coefficient, is the train running speed (m / s), is the main span length; Finally, in the amplitude analysis of the main girder, the mid-span vertical amplitude is obtained by frequency domain integration, and compared with the specification calculation limit value to evaluate the safety state of the bridge.

4. The method of claim 1, wherein: Step C selects the data during the typhoon, analyzes the vibration of the cable, and the analysis content includes acceleration analysis, vortex vibration calculation and amplitude analysis, and forms a wind-induced vibration analysis report during the typhoon, and the specific process is as follows: First, the acceleration analysis of the cable includes time history curve analysis and Fourier transform spectrum analysis, the vortex vibration calculation of the cable is calculated according to the specification formula, and the calculation results of highway and railway are compared, and the vortex vibration calculation formula of the cable is as follows: （3） wherein, is the vortex amplitude (m), is the Strouhal number, is the Scruton number, is the cable or guy diameter (m), is the standard deviation of the lift coefficient, is the cable or guy damping ratio, is the air density (kg / m 3 ), is the cable or guy mass per unit length (kg / m), is the wind speed (m / s); Then, in the amplitude analysis of the cable, the mid-span vertical amplitude is obtained by frequency domain integration, and compared with the specification calculation limit value to evaluate the safety state of the bridge.

5. The method for evaluating long-span bridge under typhoon according to claim 1, wherein: Step D combines the data before and after the typhoon, analyzes the multi-index extreme value change of the bridge structure under the action of the typhoon, extracts the extreme value before and after the action of the typhoon and performs comparative analysis, compares the extreme value with the safety threshold, and judges the safety state of the structure, and the specific process is as follows: The extracted extreme value includes the maximum value, the minimum value and the range before and after the typhoon; The safety threshold is composed of the bridge design calculation value and the bridge specification limit value; The analysis indexes include wind speed, temperature, deflection, displacement of beam end, rotation of beam end, transverse displacement and amplitude, cable force and acceleration.

6. The method for evaluating long-span bridge under typhoon according to claim 1, wherein: The variation analysis in Step E includes drawing time-history curve variation graph and correlation graph, and analyzing correlation through linear fitting.

7. The method of claim 6, wherein: The analysis indexes in Step E include wind speed, temperature, deflection, displacement of beam end, rotation of beam end, transverse displacement and amplitude, cable force, acceleration.

8. The method of claim 1, wherein: The bridge safety evaluation report after the typhoon in Step F contains two parts of wind-induced vibration analysis report during the typhoon and bridge detection index comparison analysis report before and after the typhoon.

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