高铁隧道口无砟轨道系统温度分布特征及变形协调机理

In order to build high-speed railway in the complex terrain environment of China, a large number of high-speed railway tunnels are inevitably built. Problems of the adaptability between different types of ballastless tracks and tunnels are highlighted. Due to the change of the sectional area of tunnel portal and the speed and interval of trains in high-speed railway, the temperature distribution near tunnel portal is also different from that of the general railway. The complex temperature distribution characteristics of ballastless tracks under the influence of temperature transition zones of tunnel portal will be an important factor affecting the safety service of the ballastless track in these areas..In this project, firstly, we will establish a fluid-solid-thermal coupled analysis model which can consider ambient temperature and ballastless track temperature under the influence of aerodynamic flow field caused by high-speed vehicle travelling. Secondly, we will analyze the temperature distribution law of tunnel portal and the changing process of complex temperature distribution in ballastless track in terms of different areas, tunnel alignment, travelling speeds and running intervals. Finally, we will do research into the stress transmission system and the deformation coordination problem of the ballastless track in temperature transition zones of tunnel portal..This project aims to analyze the temperature distribution law of tunnel portal and ballastless track under the influence of aerodynamic flow field caused by high-speed vehicle travelling, simultaneously, the deformation and stress characteristics of ballastless track in tunnel portal are also analyzed. The research results will provide theoretical support for the design parameters and design theory system of high-speed railway ballastless track and the ballastless track design of the tunnel group in the Sichuan-Tibet railway.

在我国复杂地形环境下修建高速铁路，必然涉及大量的隧道。随着高速铁路隧道的建设，多种型式无砟轨道与隧道之间的相互适应性问题也随之凸显。由于高铁隧道口断面面积、列车行车速度及间隔的变化，隧道口附近温度分布特征也较普速铁路有着明显的差异。隧道口温度过渡段影响下的无砟轨道复杂温度分布特征将成为影响该区域无砟轨道安全服役的重要因素。.本项目拟通过建立能够考虑高速行车气动流场影响的环境温度、无砟轨道温度的流-固-热耦合分析模型，对不同区域、不同隧道线型、不同行车速度与间隔时隧道口温度分布规律及无砟轨道内复杂温度分布规律进行分析，继而对隧道口温度过渡段内无砟轨道传力体系及变形协调问题进行研究。.本项目旨在研究环境和高速行车气动效应对隧道口处无砟轨道温度分布特征，以及隧道口复杂温度分布影响下无砟轨道受力及变形协调机理，研究成果将为丰富我国高速铁路无砟轨道设计关键参数及川藏线隧道群无砟轨道设计提供理论支撑。

在我国复杂地形环境下修建高速铁路，必然涉及大量的隧道。随着高速铁路隧道的建设，多种型式无砟轨道与隧道之间的相互适应性问题也随之凸显。由于高铁隧道口断面面积、列车行车速度及间隔的变化，隧道口附近温度分布特征也较普速铁路有着明显的差异。隧道口温度过渡段影响下的无砟轨道复杂温度分布特征将成为影响该区域无砟轨道安全服役的重要因素。. 课题组在国内外隧道口环境温度与无砟轨道温度研究的基础上，通过建立长期环境温度变换影响下隧道口无砟轨道温度场变换规律分析模型、高速行车作用下环境温度动态变换规律分析模型，掌握了不同环境、不同行车速度、不同行车间隔、不同隧道断面等影响下无砟轨道复杂温度场变换规律。同时开展了典型地区运营高速铁路隧道口温度场动态测试，选取了高温地区的赣深铁路博罗隧道和严寒地区的敦白铁路吉昌隧道，分别于夏季和冬季进行了行车过程中隧道口温度测试，获取了典型极端环境下隧道口温度分布试验数据与规律，验证了分析模型。最后建立了基于无砟轨道复杂温度变换影响下无砟轨道-无缝线路和桥隧过渡段温度荷载传递仿真分析模型，获取了隧道口温度过渡段内无砟轨道系统与隧道之间力与位移传递机理。. 综上所述，本项目建立气动流场与温度场耦合作用关系分析模型，揭示高速行车条件下隧道口温度场分布特征，并分析隧道口附近无砟轨道系统的力学行为与变形协调机理，项目的完成将为高速铁路隧道口无砟轨道设计提供完善的关键参数与设计方法，使高速铁路线路设计更为科学合理，同时为高速铁路走出去战略提供更为完备的理论支撑。