中文摘要：

高速铁路桥梁沉降会使桥上无砟轨道产生下沉,影响列车的安全平稳行驶,桥上道岔区尤为敏感.为了研究桥梁沉降对无砟道岔结构动力特性的影响,本文基于有限元软件ABAQUS建立车辆-道岔-无砟道床-高架桥梁耦合动力学模型,从轮轨相互作用、道岔部件的动力性能、车辆运行安全平稳性、道岔板动力性能、桥梁结构动力性能5个方面,对沉降条件下车岔桥耦合系统的动力性能进行研究.结果表明：桥梁沉降对于轮轨垂向相互作用、脱轨系数和轮重减载率影响较大;桥梁沉降对车体振动、无砟道床和桥梁动态特性的影响相对较小;桥梁沉降直接影响岔区高速行车的安全性和平稳性,应进行严格控制.

英文摘要：

High-speed railway bridge settlements will cause ballastless tracks on bridge to subside and affect safe and stable operation of trains, and the bridge turnout area is most sensitive. In order to research the influence of bridge settlements on the dynamic properties of the ballastless bridge turnout structure, the dynamic model of the coupled system of vehicle--turnout--ballastless track--elevated bridge was established with the finite el- ement analysis software ABAQUS. By the model, the dynamic performance of the vehicle-turnout-bridge cou- pled system in settlement was studied in respect of wheel-rail interaction, dynamic performance of turnout parts, safety and stability of vehicle running operation, dynamic performance of turnout slabs and dynamic performance of bridge structures. The results show as follows.. The impacts of bridge settlements on vertical wheel-rail interactions, derailment coefficients and wheel unloading rates are great; the influences of bridge settlements on vibration of vehicles, ballastless track and dynamic characteristics of bridges are relatively small; bridge settlements directly affect safety and stability of high-speed train in the turnout area, so strict control should be exercised.