Three-dimensional Coupled Vibration Of Wind-vehicle-bridge System Considering Driver's Behavior

The new era of bridge construction has been coming when lots of world famous bridges across bays or gulfs are under constructing during the 21st century and some of cross-sea bridges spanning gulf have been constructed one by one in China. In order to avoid the difficulty in deep water base construction and meet the need of navigation, long-span bridges will be the best alternative for a cross-gulf bridge. The safety analysis and ride comfort assessment of road vehicles subjected to crosswinds running on an oscillating bridge is not only a scientific issue and the decision on the threshold of wind speed above which the bridge should be closed to road vehicles become important social and economic issue.Firstly, the current contents that consist of wind-vehicle-bridge coupling analysis and driver behavior model under strong side wind environment are reviewed. The wheel side-slipping strength model and driver behavior model considering moving automobiles' coordinate rotation characteristics under side wind are studied, so the vehicle-bridge lateral coupling relations have been developed. A more reasonable automobile dynamic analysis model that considers many factors is adopted. The adoption of driver model has been added into time domain solution process based on separated iterative method, thus the analysis frame ands solution strategy of the wind-vehicle-bridge coupling vibration of considering driver behavior are established, and corresponding programs are accomplished under Fortran development environment. Then, the side-slipping and over-turning critical wind speeds of the automobile under different wind direction are analyzed.Secondly, the example of FFT's failure in identifying a bridge buffeting response spectrum is provided. The Hilbert-Huang Transformation (HHT) is introduced to analyze the time-frequency characteristics of buffeting response. The reason of responses' non-stationary characteristics is probed into from the perspective of structure dynamics, the physical meaning of HHT is discussed from the view of wind engineering. The non-stationary index of automobiles' supporting force response under side wind is analyzed, which confirms the reasonableness of stationary assumption in dynamic reliability analysis.Thirdly, joint distribution of wind speed and wind direction is established based on the extensive extreme value distribution, which is used for reliability analysis of bridge traffic safety. The failure problem of maximum likelihood parameter estimate of broad extreme value distribution is put forward. Iterated-gradually estimated algorithm method is extended to the extensive extreme value distribution. Highly efficient and stable method of parameter estimation is built. The fitting degree of extensive extreme value distribution and the extremeâ… ,â…¡,â…¢type distribution was compared, among which the optimal distribution type are researched.Finally, the models of bridge traffic safety probabilistic evaluation are discussed and established. The influence of the random process characteristics of fluctuating wind velocity and road roughness on traffic safety reliability level is analyzed. The evaluation method based on the dynamic reliability theory with consideration of joint distribution of wind velocity and direction is established...