高速铁路道岔轮轨接触行为、性能演化与损伤机理研究

For the three typical damage problems which are urgently needed to be solved in the long-life and safe service of high speed railway turnout, the method combined with theoretical research, simulation analysis, indoor and field test is applied to investigate the evolution and influence mechanism of wheel rail relation for railway turnouts, the wheel rail transient contact and high frequency vibration fatigue in railway turnout, the wear mechanism of the turnout rail and the control measures. The target of the study is to explore constructing the system of long term service performance and operation safety insurance of high speed railway turnout. The three-dimensional rigid-flexible coupling model of train-turnout system is established to research the influence mechanism of the evolution of wheel-rail relation on rolling contact fatigue, then the dynamic combined profile optimization of turnout rail is performed to guide the grinding of the turnout rail in high speed railway. Based on the wheel-turnout rail transient contact model, the waveguide characteristics of turnout rail, material cyclic constitutive and fatigue failure models, the high frequency vibration fatigue analysis method is established to reveal wheel rail transient contact behavior and high frequency vibration transmission characteristics of high speed railway turnout. The study can provide technical supports for the real-time monitoring of turnout rail vibration fatigue in high frequency. Based on the three-dimensional dynamics as well as material wear model, the simulation analysis method of the turnout rail wear is established to explore the characteristics and evolution rules of non-uniform wear of the turnout rail, which provides a theoretical basis for the wear reduction and structural optimization of the turnout rail. The achievements have great theoretical significance and practice as well as promotional value for ensuring the safe operation and realizing scientific maintenance of high speed railway turnout.

针对高速道岔长寿命安全服役亟待解决的三类典型损伤问题，应用理论研究、仿真分析、室内及现场试验相结合的方法，开展道岔轮轨关系演变及影响机制、岔区瞬态接触与高频振动疲劳、道岔钢轨磨耗机理与减缓措施研究，探索构建高速道岔长期服役性能与运营安全保障体系。建立列车-道岔刚柔耦合三维动力学方法，探明道岔轮轨关系演变对滚动接触疲劳的影响机制，提出道岔动态组合廓形优化设计，指导高速道岔钢轨打磨；建立基于道岔瞬态接触模型、钢轨波导特性、材料循环本构模型及疲劳失效模型的高频振动疲劳分析方法，揭示岔区瞬态接触行为及高频振动传递特性，为道岔高频振动疲劳实时监测提供技术支撑；建立基于三维动力学与材料摩擦磨损模型的道岔钢轨磨耗仿真分析方法，探明道岔钢轨非一致性磨耗特征及演变规律，为道岔钢轨磨耗减缓及结构优化提供理论依据。其成果对确保高速道岔的安全服役、实现高速道岔的科学养护维修具有十分重要的理论意义和实践推广价值。

针对高速道岔长寿命安全服役亟待解决的三类典型损伤问题，应用理论研究、仿真分析、室内及现场试验相结合的方法，开展道岔轮轨关系演变及影响机制、岔区瞬态接触与高频振动疲劳、道岔钢轨磨耗机理与减缓措施研究，探索构建高速道岔长期服役性能与运营安全保障体系。取得的重要成果有：（1）建立了考虑轮对和道岔钢轨柔性变形的轮轨接触几何算法，以及高速车辆-道岔刚柔耦合动力学模型，研究了岔区柔性轮轨动力特性及并进行了时频响应分析。（2）开展了高速道岔轮轨关系演化规律及其动态组合廓形优化研究，分析了高速道岔轮轨关系演变对车辆过岔动态性能的影响机制，形成了高速道岔轮轨动态组合廓形优化设计方法，基于此进行了直基本轨廓形优化与钢轨表面RCF伤损分析。（3）建立高速道岔转辙器轮轨瞬态滚振动接触有限元模型，阐明了车轮过转辙器时的轮轨瞬态滚动接触行为，分析了不同轮轨参数对轮轨接触动力响应的影响；建立了道岔辙叉区三维轮轨瞬态滚动接触冲击有限元模型，阐明了车轮过辙叉时的轮轨接触冲击行为，研究了关键轮轨参数对车轮过辙叉宏观及微观动力响应的影响。（4）研究了高速道岔钢轨频散特性，开展了钢轨波导特性现场试验研究；分析了不同超声导波在钢轨中的传播特性，基于此筛选了合适的超声导波激励方式，并开展了高速道岔尖轨断轨检测研究。（5）开展了钢轨材料的冲击动态实验和循环变形实验，提出了钢轨循环塑性本构模型，利用该本构模型开展了含螺栓孔缺陷的道岔钢轨受力特性分析，以及螺栓孔处钢轨疲劳裂纹扩展分析。（6）结合道岔区轮轨瞬态滚动接触有限元模型及轮轨材料磨耗模型，构建了高速铁路道岔钢轨非一致性磨耗仿真预测方法，根据尖轨磨耗影响因素分析，进行了高速铁路道岔尖轨磨耗减缓措施研究。研究成果对确保高速道岔的长期服役安全、实现道岔结构的科学养护维修具有十分重要的意义。