【作者】 马麟；

【导师】 刘健新；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2008， 博士

【摘要】 21世纪的世界桥梁工程步入了建设跨海联岛工程的新时期，中国也开始了跨海工程建设，长大桥梁是跨海工程的有力竞争者，但带来了因桥位处大风频袭所导致的风对通行车辆的影响问题。在强风作用下，行使在振动桥梁上的车辆的安全性和舒适性研究不仅是一个科学问题，而且也是一个急待解决的工程问题，同时强风作用下关闭交通的临界风速标准的确定是一个影响广泛的社会问题和经济问题。首先对现有解决风环境下车辆行驶问题的驾驶员反应行为模型、风-汽车-桥梁耦合分析组成内容进行了回顾，研究了考虑汽车运动时坐标转动特性的驾驶员行为模型和桥面车轮侧滑力模型，发展了汽车-桥梁的侧向耦合关系，采用了一个更加合理，能考虑众多因素影响的汽车动力分析模型，将驾驶员模型的运用融入到整体的风-汽车-桥梁分离迭代法的时域求解过程中去，从而建立了考虑驾驶员行为的风-汽车-桥梁系统空间耦合振动分析框架及求解策略，用Fortran实现了相应的程序功能。在此基础上探讨桥面振动对行车事故相关响应的影响，分析了不同风向下桥面行车的侧滑、侧倾临界风速。其次提供了Fourier变换识别抖振响应频谱失真的实例，采用Hilbert-Huang变换(HHT变换)分析桥梁抖振响应的时频特性，从结构动力学角度探讨了响应非平稳性的原因，从风工程的角度探讨HHT变换分量的物理意义，并分析侧风作用下桥上汽车支撑力响应的非平稳指标，为动力可靠度分析中平稳性假定的合理性提供必要的论证。再次建立了基于广义极值分布的风速风向联合分布，为桥上行车安全的可靠度分析提供了风速概率模型。针对极大似然法参数估计的失效问题，将逐步迭代法推广应用于广义极值分布，建立了参数估计的高效稳定算法，并比较广义极值分布与极值Ⅰ、Ⅱ、Ⅲ型分布的拟合度，研究平均风速的最优分布类型。最后探讨并建立桥面行车安全概率评价的模型。分析了风-汽车-桥梁系统脉动风及路面粗糙度样本的随机过程特性对行车安全可靠度的影响，建立了考虑风速风向联合概率分布的动力可靠度评价方法。更多还原

【Abstract】 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 extremeⅠ,Ⅱ,Ⅲtype 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更多还原