基于非介入策略的参数不确定车辆-结构耦合系统随机振动研究

The coupling vibration of the train and structure is a typical moving boundary problem. Due to the non-ideal smooth of the contact boundary and relatively high-speed motion between the subsystems, the broadband random vibration induced by the track irregularity is a significant feature, which is closely related to the fatigue and damage of the system components. On the other hand, in the high-speed motion state, the vehicle dynamic performance has become more sensitive to the uncertainty possessed by the system. For the high reliability of the system operation, the development of effective theory and method is carried out to study of the random vibration of the vehicle and structure coupling system with parameters, which is only challenging, but also is an important development direction of computational structural dynamics. In this proposal, the dynamic model of mixed physical and modal coordinates based on the coupling system interaction conditions will be investigated. In the framework of symplectic dual system, the wave theory will be used to establish an efficient random vibration analysis method for vehicle and track coupling system. The generalized spectrum and the pseudo excitation method will be used to study the evolution of the non-stationary random vibration for the vehicle and bridge coupling system. Based on the above, the stepwise regression technique will be applied to the dynamics of vehicle and structure coupling system with the uncertain parameters, and the stochastic collocation method based on non-intrusive strategy will be proposed to quantitatively evaluate the uncertainty response of the vehicle and structure coupling system. This proposal has certain value to the further development of coupling dynamics theory, and also has reference significance for the design and maintenance of high-speed railway.

列车和结构耦合振动是典型的动边界问题。由于相互作用系统接触边界非理想光滑及相对高速运动，轨道不平顺诱发的宽带随机振动成为显著特征，其与系统关键部件的疲劳损伤密切相关。此外，在高速运动状态下，车辆动力学性能对于系统客观存在的不确定性也变得更为敏感。对于系统运行的高可靠性，发展有效的理论和方法揭示参数不确定车辆-结构耦合系统随机振动行为机理不仅颇具挑战，也是计算结构动力学的一个重要发展方向。为此，本项目将依据耦合系统相互作用条件开展混合物理和模态坐标的动力学建模方法研究，基于辛对偶体系建立车轨耦合系统宽带随机振动高效分析的波动方法，发展广义谱分析和虚拟激励法探讨车桥时变耦合系统的非平稳随机振动演化机制。在上述基础上，将逐步回归技术应用于参数不确定车辆-结构耦合系统动力学，基于非介入策略提出不确定响应量化评估的随机配置法。本项目对耦合动力学理论深入发展具有价值，对高速铁路设计与维护也有借鉴意义。

在高速运动状态下车辆动力学性能对于系统客观存在的不确定性也变得更为敏感，对于系统运行的高可靠性，发展有效的理论和方法揭示参数不确定车辆-结构耦合系统随机振动行为机理不仅具有挑战，也是计算结构动力学的一个重要发展方向。本项目组基于在随机振动及计算力学领域的研究基础开展了相关理论和数值研究，进行的主要工作包括：依据车轨耦合系统相互作用条件提出了混合物理和模态坐标的动力学建模方法；基于辛对偶体系建立了车轨耦合系统宽带随机振动高效分析的波动方法，发展了广义谱分析和虚拟激励法探讨了车桥耦合系统的随机振动演化机制；将稀疏正交多项式应用于参数不确定车辆-结构耦合系统动力学，基于非介入策略提出不确定响应量化评估的随机配置法。相关工作对耦合动力学理论发展具有一定价值，对高速铁路设计与维护也有一定借鉴意义。