摘要
重载列车在提高运输效能的同时也会加剧对基础设施结构的损伤,甚至影响行车安全,因此,开展系统的重载铁路隧道动力响应特性研究具有重要的现实意义。模型在系统分析列车、轨道、隧道底部结构与围岩间相互作用关系的基础上,分别通过赫兹非线性理论定义轮-轨接触和通过修改钢轨竖向坐标的二次建模方法引入轨道不平顺,重点分析和表征了各列车机构、隧道结构体系之间的相互耦合关系,建立了车辆-轨道-隧道一体化三维耦合有限元数值模型,并开展对比验证。研究结果表明:模型的计算结果与既有文献中的实测数据相差较小,最大相对差值为12.2%,说明所建立的车辆-轨道-隧道一体化耦合模型及其参数的选取是合理可靠的。在此基础上,进一步针对列车轴重、围岩条件、填充层厚度和轨道条件4个关键因素对重载铁路隧道底部结构的动力响应影响规律开展了共计15个工况的模拟计算。研究结果表明:隧道底部结构及基岩的主应力、沉降变形均随列车轴重的增大、围岩条件的变差以及填充层厚度的减薄而快速呈线性增大;列车轴重和围岩条件对底部结构的动力响应影响最为显著;适当增加填充层厚度能减轻列车动载对隧道底部结构的冲击作用,对于Ⅳ-Ⅵ级围岩地段,建议填充层厚度不宜小于1.33 m。
While heavy trains improve transportation efficiency, they also aggravate the damage to infrastructure structures, and even affect train operation safety. Therefore, it is of great practical significance to carry out a systematic study on the dynamic response characteristics of heavy haul railway tunnels. Based on the systematic analysis of the interaction relationship between train, track, the bottom of tunnel structure and surrounding rock,and then, the wheel-rail contact was defined by Hertz nonlinear theory and the track irregularity was introduced by the quadratic modeling method of modifying the vertical coordinates of the rail. The model focuses on analyzing and characterizing the coupling relationship between train mechanism and tunnel structure system,vehicle-track-tunnel integration three-dimensional coupled finite element numerical model was established, and the verification was carried out. The results show that there is a small difference between the calculated results and the measured data in the existing literature, and the maximum relative difference is 12.2%, which indicates that the vehicle-railway-tunnel integration coupling model and its parameters are reasonable and reliable. On this basis, a total of 15 working conditions are simulated for the influence of train axle load, surrounding rock condition, filling layer thickness and track condition on the dynamic response of the bottom structure of heavyhaul railway tunnel. It indicates that the principal stress and settlement deformation of tunnel bottom structure and bedrock increase linearly with the increase of train axle load, the deterioration of surrounding rock condition and the thinning of filling layer thickness;the train axle load and surrounding rock conditions have the most significant effect on the dynamic response of the bottom structure;appropriately increasing the thickness of filling layer can reduce the impact of train dynamic load on the tunnel bottom structure. For the surrounding rock grade IV-VI, it is suggested that the thickness of filling layer should not be less than 1.33 m.
作者
肖鹏
彭立敏
李锐
王海林
雷明锋
XIAO Peng;PENG Limin;LI Rui;WANG Hailin;LEI Mingfeng(Hunan Provincial Communications Planning,Survey&Design Institute Co.,Ltd.,Changsha 410020,China;School of Civil Engineering,Central South University,Changsha 410075,China;Shuohuang Railway Development Co.,Ltd.,Beijing 100000,China;Key Laboratory of Engineering Structure of Heavy Haul Railway,Changsha 410075,China)
出处
《铁道科学与工程学报》
EI
CAS
CSCD
北大核心
2022年第12期3737-3745,共9页
Journal of Railway Science and Engineering
基金
国家自然科学基金资助项目(51978669,U1934211)
湖南省自然科学基金资助项目(2021JJ30825)
朔黄铁路发展有限责任公司科技创新项目(SHTL-19-21)。
关键词
重载铁路隧道
车-轨-隧耦合模型
动力响应特性
影响因素
heavy haul tunnel
train-track-tunnel coupling model
characteristics of dynamic response
influence factors
