【作者】 崔圣爱；

【导师】 祝兵；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2009， 博士

【摘要】 客运专线和高速铁路的大规模兴建和列车速度的不断提高,以及越来越多的超大跨度跨海大桥的建设,为建立车桥耦合振动的精细化数值仿真模型提出了必然的需求。现有的车辆与桥梁的耦合振动研究中,在建立车辆动力学模型时,主要采用传统动力学分析方法拉格朗日第二类方程或牛顿-欧拉方程导出位置与姿态坐标的运动微分方程。随着铁路科学技术的发展,研究的车辆动力学模型越来越复杂,同时从车桥耦合振动研究中车辆分析模型的发展趋势看,需要进一步抽象和细化车辆动力学各元件对象模型,特别是考虑悬挂非线性问题,用手工符号推导动力学方程将面临相当繁重的代数和微分运算,并且非常容易出错,为此,不得不将系统作许多强制性的简化,降低自由度,但这样做很难揭示复杂的动力学性态,也很难满足精细化仿真的要求,使用多体系统动力学方法进行程式化的建模成为一种必然的选择。对桥梁进行有限元模拟时,一般采用空间杆系有限元法,而高速铁路桥梁的截面形状多为空心箱形截面,为了更准确的考虑梁体在高速列车作用下的空间挠曲以及扭转变形的特点,需要采用空间板壳单元模拟梁体。对于采用摩擦桩基础的桥梁,建立桥梁动力学模型需要同时考虑梁体—桥墩—桩基础—桩土相互作用的共同影响。随着计算机技术、有限元分析理论与多体系统动力学的发展,车辆—桥梁各子系统的精细化仿真分析及系统链接的实现成为了可能,车辆的动力学行为可以使用多体系统动力学方法进行分析,桥梁等弹性结构则使用有限元方法进行分析,然后将两个子系统在轮轨接触面离散的信息点上进行数据交换实现联合仿真。将多体系统动力学软件SIMPACK与有限元软件ANSYS结合起来,为车桥耦合振动的联合仿真分析构建了平台。本文首先介绍了多体系统动力学的基本理论,利用多体系统动力学方法建立了车辆三维空间精细化仿真模型,充分考虑了模型中的各种非线性因素,除了轮轨接触几何关系,轮轨蠕滑力计算非线性特性外,还充分考虑了机构参数中的各种非线性因素,并计算了车辆的线性临界速度和非线性临界速度。介绍了桥梁动力模型的有限元法、动力子结构技术的实现以及求解自振特性的原理。其次,针对弹性轮轨接触和约束轮轨接触,分别建立了多体系统中轮轨接触的运动方程,分析了轮轨接触点的求解方法及两种接触时法向力的求解原理。根据轮轨运动学关系,详细推导了Kalker简化理论—FASTSIM算法的实现过程。在分析多体系统动力学和有限元方法耦合集成的基础上,建立了多体系统和有限元数据交换过程的计算流程,并介绍了基于BDF的DASSL算法。以高速铁路简支梁桥为例,进行了车桥耦合振动仿真分析,证明了方法的可行性和有效性。最后,以客运专线大跨度连续梁桥和琼州海峡跨海工程超大跨度斜拉桥方案为研究对象,建立了车桥耦合振动三维精细化仿真模型。采用基于多体系统动力学和有限元法的联合仿真技术,进行了动车组列车通过桥梁时的仿真研究。针对大跨度连续梁桥,建立了同时考虑梁部、桥墩、桩基础和桩土相互作用的完整的桥梁动力学模型。对弹性轮轨接触和约束轮轨接触从理论上进行比较,并对两种接触时的车桥耦合振动响应进行了对比分析,研究了轮轨接触对车桥耦合振动的影响,分析了其适用性；对单线行车、双向对开以及两列车以不同车速双向对开时的车桥耦合振动仿真结果进行了对比分析；从比较秦沈线轨道谱、德国低干扰及德国高干扰谱三种谱功率谱密度和时间样本幅值的差异并结合三种谱时的车桥耦合振动动力参数的对比分析,探明了秦沈客运专线轨道谱与德国轨道谱之差异,探究了不平顺谱波长成分对车桥动力参数的影响；分析了阻尼比对桥梁动力响应的影响。针对琼州海峡跨海工程斜拉桥方案,采用空间板壳和杆系混合单元有限元法建立了斜拉桥动力分析模型。仿真计算了列车以不同车速单线行车和双向对开通过该大跨度斜拉桥的空间耦合振动响应,检算该方案桥是否具有足够的横向、竖向刚度及良好的运营平稳性。更多还原

【Abstract】 With the large-scale construction of passenger dedicated railway and high-speed railway, continuous improvement of train speed, and construction of more and more crossing-channel bridges, to establish refined numerical simulation model for coupled vibration between vehicle and bridge become an inevitable demand. In existing studies of coupled vibration for vehicle-bridge system, differential motion equations of coordinates of position and attitude are derived by traditional kinetics analysis method the second kind Lagrange equation and Newton-Euler equation when establishing vehicle dynamics model. With the development of railway science technology, the vehicle dynamics models foe study become more complex. On the other hand, the component object models of vehicle dynamics need to be futher abstracted and refined, especially nonlinear problems of suspension should be considered. Therefore heavy algebra and differential operations will be confronted with when deriving dynamic equations by manual symbols, and errors may be encountered easily. To this end, many mandatory simplifications have to be done for the system, and degrees of freedom are reduced. As a result, it is difficult to reveal the complex dynamic behaviour, and it is hard to meet the requirement of refined simulation. So it is an inevitable choice to establish programming model by multi-dynamics approach. The bridge dynamic model usually is established by Space bar finite element method. Because the cross-section shape of high-speed railway bridges is mostly hollow box section, space shell element is used to simulate girder to more accurately consider space deflection and torsion of girder under high-speed train. For the bridges with friction pile foundation, the girder-pier-pile foundation-interaction between pile and soil are all should be considered when establishing dynamic models.With the development of computer technology, finite element analysis theory and multi-body system dynamics, refined simulation of each subsystem for vehicle-bridge system and link of systems may be realized. Dynamic behavio of vehicle can be analyzed by multi-body system dynamics method, and flexible structure (such as bridge) can be analyzed by finite element method, and then the co-simulation of two subsystems (vehicle and bridge) is performed by the interfacing data exchange at discrete communication points. The co-simulation platform for coupled vibration between vehicle and bridge is constructed by integration of multi-body system dynamics software SIMPACK and finite element software ANSYS.Firstly, basic theories of multi-body system dynamics are intrduced. The refined three-demensional space vehicle model is set up by multi-body system dynamics method, and the multiple non-linear properties including all kinds of non-linear factors of mechanism parameters besides wheel/rail contact geometry and creep forces are considered. Linear and non-linear critical speeds are calculated. Finite element method of dynamic model of the bridge, dynamic substructure technology and principle of solving vibration characteristic are intrduced.Secondly, the motion equations are established in multi-body system for elastic wheel/rail contact and constraint wheel/rail contact, solving method of wheel/rail contact point and wheel/rail normal force are analyzed. According to wheel/rail kinematic relation, the realization process of Kaller simplified theory-FASTIM algorithm is detailedly derived. Based on coupled integration of multi-body system dynamics and finite element method, calculation process of exchange data between multi-body system dynamics and finite element is set up, and DASSL algorithm based on BDF is introduced. Taking a simply supported beam bridge on high-speed railway as example, coupled vibration between vehicle and bridge is simulated. Feasibility and validity of the method are confirmed.Finally, taking a long-span continuous beam bridge on passenger dedicated railway and super-large cable-stayed bridge scheme of crossing-channel project over Qiongzhou strait as study objects, the 3D refined simulation models of coupled vibration between vehicle and bridge are established. The simulation reaearchs are completed when the motor train runs through the bridges by co-simulation techonology based on multi-body system dynamics and finite element method.For long-span continuous beam bridge, whole dynamic model of the bridge is established, and girder, bridge pier, pile foundation and pile-soil interaction are all considered simulately. The impact of wheel/rail contact on coupled vibration between vehicle and bridge and applicability of wheel/rail contact are studied by comparing theory difference of two wheel/rail contact (elastic contact and constraint contact) and resultes of simulation analysis of coupled vibration between vehicle and bridge. The simulation resultes of coupled vibration are compared and analyzed when only a motor train passes the bridge and when two trains pass bridge with the opposite direction at equal or uneqal speed. By comparison and analysis of PSD, time-sample amplitude of three kindes spectrums (QS track spectrum, German railway spectrum of high irregularity and low irregularity) and dynamic parameters of coupled vibration for vehicle-bridge system, the difference of track spectrum of QS passenger railway line and typical track spectrum abroad is proved, and the impact of wavelength components of the irregularity spectrums on dynamic parameters of vehicle-bridge system is explored. Impact of damping ration on dynamic response of the bridge is analyzed.For super-large cable-stayed bridge scheme of crossing-channel project over Qiongzhou strait, the dynamic analysis model of cable-stayed bridge is established by use of space bar-shell hybrid finite element method. The space vibration responses are calculated by co-simulation based on multi-body system dynamics and finite element method when the train runs through the long span cable-stayed bridge at different speeds in order to test if the bridge has the sufficient lateral or vertical rigidity and the operation stability is fine.更多还原