车辆循环动载下高速铁路路基累积变形预测研究

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国家科技期刊平台
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中文摘要：高速铁路路基在车辆荷载反复作用下不可避免地产生累积变形,影响铁路轨道-路基结构服役性能和车辆运行品质.为探明高铁路基在循环车辆动载下的累积变形空间分布特性和长期发展规律,建立车致路基累积变形预测模型,其主要由2个子模块组成:1)基于多体动力学和有限单元法建立的高速铁路车辆-轨道-路基耦合时变动力学模型;2)基于建立的车辆-轨道-路基动力相互作用模型,引入路基累积变形预测模型,利用循环跳跃的方式预测不同车辆荷载累积次数下路基的累积变形及其空间分布规律.2个模块的交互方面,在每次循环跳跃后,将路基累积变形空间映射至轨道,形成轨面附加几何不平顺,并同步更新迭代系统动力矩阵,建立了车致路基累积变形与系统动力响应之间的关联关系.研究结果表明:本文提出的计算模型可较好地揭示路基土体累积变形在循环车辆动载下的演化规律;采用循环跳跃的方法可更为真实准确地预测路基的累积变形,其计算的路基累积变形最大值为2.606 9 mm,而未采用循环跳跃方法计算出的累积变形最大值则为1.7 mm,低估了34.8%.路基累积变形在前期发展较快,后期由于土体被不断夯实,累积变形的演化呈现减缓趋势,累积变形速率从1次加载0.035 mm减小到1次加载小于10-6 mm;在路基具有初始不均匀变形的区域内,路基累积变形的幅值大于路基没有初始不均匀变形的区域;路基的累积变形对系统的垂向动力响应的影响显著,动力响应表现为增大的趋势;对于系统的横向振动,累积变形的影响较小.本文提出的方法和研究结果可为高速铁路路基不均匀累积变形控制和预测提供技术支撑.

外文标题：Study on the prediction of the cumulative deformation of high-speed railway subgrade under the cyclic dynamic loads of vehicle

外文摘要：High-speed railway subgrade inevitably produces cumulative deformation under repeated vehicle loadings,affecting the in-service performance of railway track-subgrade structure and operation quality of high-speed train.To investigate the spatial distribution characteristics and long-term development laws of cumulative deformation of high speed railway subgrade under cyclic dynamic vehicular loads,a prediction model for vehicle-induced cumulative deformation of high speed railway subgrade was established,which mainly consisted of two sub-modules:1)a time-varying dynamic model of high-speed railway vehicle-track-foundation coupling based on multibody dynamics and finite element method;2)based on the established vehicle-track-subgrade dynamic interaction model,a subgrade cumulative deformation prediction model was introduced to predict the deformation of subgrade and its spatial distribution law under different vehicle load cumulative cyclic times by using the cyclic jumping method.For the interaction of the two modules,after each cyclic jump,the subgrade cumulative deformation was mapped to the track system.The spatial mapping additional geometric irregularity of the track and dynamic matrix of interaction system was updated simultaneously,which established the correlation between the vehicle-induced subgrade cumulative deformation and the dynamic responses of the system.The results show that the calculation model presented in this paper can well reveal the evolution law of subgrade cumulative deformation under cyclic dynamic vehicular loads.The research results show that the calculation model proposed in this paper can well reveal the evolution law of the cumulative deformation of the foundation soil under cyclic vehicle dynamic loads.The maximum cumulative deformation of the subgrade calculated by the cyclic jump method is 2.606 9 mm,while the maximum calculated without adopting the cyclic jump method is 1.7 mm,which corresponds to an underestimation of 34.8%.The cumulative deformation of the subgrade developed rapidly in the early stage.In the later stage,due to the continuous compaction of the soil,the evolution of the cumulative deformation shows a slowing trend,and the cumulative deformation rate decreased from 0.035 mm/cycle to less than 10-6 mm/cycle.In the region with initial differential subgrade deformation,the amplitude of the cumulative deformation of the subgrade is larger than that without initial differential subgrade deformation.The cumulative deformation of the subgrade has a significant effect on the vertical dynamic responses of the system,and the dynamic responses show an increasing trend.The cumulative deformation has little effect on the lateral vibration of the system.The method and results presented in this paper can provide technical support for the control and prediction of differential cumulative deformation of high-speed railway subgrade.

外文关键词：

railway engineeringvehicle-track-subgrade dynamic interactionsubgrade cumulative deformationspatial geometry mappingtime-varying dynamic system

作者：

李正、徐磊、王卫东、杜香刚、余志武、刘鹏飞、曾志平

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作者单位：

中南大学土木工程学院,湖南长沙 410075

高速铁路建造技术国家工程研究中心,湖南长沙 410075

湖南铁院土木工程检测中心,湖南长沙 410075

中南大学重载铁路工程结构教育部重点实验室,湖南长沙 410075

中国铁道科学研究院集团有限公司铁道建筑研究所,北京 100081

石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室,河北石家庄 050043

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关键词：

铁道工程车辆-轨道-路基动力相互作用路基累积变形空间几何映射时变动力系统

基金：

国家重点研发计划"交通基础设施"重点专项揭榜挂帅项目国家自然科学基金国家自然科学基金国家自然科学基金中国中铁重大专项中国中铁重大专项中国中铁重大项目中国国家铁路集团科技研发计划中国国家铁路集团科技研发计划

项目编号：

2022YFB26033015237846852008404U19342172020-Special-022021-Special-082021-Major-02L2022G007L2023G007

出版年：

2024

DOI：

10.19713/j.cnki.43-1423/u.T20231073

铁道科学与工程学报

中南大学中国铁道学会

铁道科学与工程学报

CSTPCD北大核心EI

影响因子：0.837

ISSN：1672-7029

年,卷(期)：2024.21(4)

参考文献量21