基床沥青混凝土层全温度域的作用机理与动态演变行为研究

The application of a thin layer asphalt cocrete with optimium waterproofing and viscoelasticity capacities on the top of current trackbed is a promising solution to maintain the high level of smoothness and stability of the various trackless slab system controbuting to the long-term operational safety. . This project aims to the mechanism of asphalt concrete track-bed interacting with Type-III slab track system of China(CRTS-III), the evolution and its effects on the dynamic responses of the whole system, which will contribute to the re-innovation of CRTS-III and optimization of asphalt track-bed. The theory and methods of Railway Dynamics, functional graded viscoelastic theory and FEM are adopted to investigate the static/dynamic responses of the new structure and the influencing factors. The dynamic behaviors of asphalt concrete track-bed in the whole working temperature range and their evolution will be proposed with consider the simulation and field monitoring results. An innovative analysis tool incorporating functionally graded viscoelasticity and semi-analytical FEM will be developed for the purpose of optimization of asphalt track-bed.. This project is believed to provide a quantitative explanation on the dynamic behaviors of asphalt concrete track-bed. And the results can also be expanded to other type of ballastless slab track system, which will be important contribution for the long-term safe operation of China High Speed Railway.

在基床顶面全宽铺设沥青混凝土层是新型防水缓冲方案，对维护无砟轨道线路的高平顺性和高稳定性、确保我国高速铁路长期安全运营至关重要。本项目旨在研究无砟轨道结构中基床顶面沥青混凝土层的作用机理与动态演化规律，为CRTS-III型结构再创新与沥青混凝土优化提供理论依据。项目综合运用轨道结构耦合动力学、粘弹性理论与有限元方法，研究无砟轨道结构线下沥青混凝土层全温度域内的静动力响应及其影响因素，结合室内试验与现场测试探明线下沥青混凝土层的工作状态和动态演变规律，发展基于半解析梯度粘弹性有限元的新型结构分析工具，提出无砟轨道结构线下沥青混凝土层材料特性参数与层厚的合理范围。. 通过本项目研究预期可为线下沥青混凝土层的动力行为提供机理性解释。研究成果亦可拓展至其他型式无砟轨道结构，对于维持我国高铁的长期安全稳定运行具有重要的应用价值。

在基床顶面的全宽铺设沥青混凝土层是新型防水缓冲方案，对维护无砟轨道线路的高平顺性和高稳定性、确保我国高速铁路长期安全运营至关重要。本项目旨在研究无砟轨道结构中基床顶面沥青混凝土层的作用机理与动态演化规律，为CRTS-III型结构再创新与沥青混凝土优化提供理论依据。项目综合运用轨道结构耦合动力学、粘弹性理论与有限元方法，分析线下沥青混凝土层非线性温度场特性，研究全温度域内的静动力响应及其影响因素，结合室内试验与现场测试探明线下沥青混凝土层的工作状态和动态演变规律，发展基于考虑沥青混凝土材料梯度特性的半解析梯度粘弹性有限元的新型结构分析工具，提出无砟轨道结构线下沥青混凝土层材料特性参数与层厚的合理范围。通过本项目研究预期可为线下沥青混凝土层的动力行为提供机理性解释。研究成果亦可拓展至其他型式无砟轨道结构，对于维持我国高铁的长期安全稳定运行具有重要的应用价值。