摘要
为在现有三层离散支撑梁有砟轨道模型中考虑路基土体间的剪切效应,在Pasternak双参数地基模型基础上对剪切层进行离散处理,采用移动单元法建立了考虑路基土体剪切效应的有砟轨道-车辆耦合动力学模型,将移动单元法与MATLAB相结合,编制计算程序,通过MATLAB数值计算,研究路基剪切效应对车-轨耦合系统的影响,以及轨道不平顺和轨枕空吊对系统动力特性的影响规律。研究结果表明,考虑路基剪切效应时,钢轨、轨枕、道砟的位移响应均有不同程度的减小,并且抑制情况从钢轨到道砟相差逐渐增大,三者的加速度响应也均有较为明显的下降,其对加速度响应的抑制效果从道砟到轨枕依次减小,但钢轨的加速度减幅大于道砟,对轮轨接触力有一定影响,但影响不明显,减幅仅为0.85%;不平顺幅值和波长特性对系统的动力响应会产生显著影响,随着幅值增大和短波成分增加,系统动力响应加剧,其中2 m左右短波不平顺和90%百分位数谱对轮轨动力特性影响显著;列车经过空吊区域时,空吊及周围区域轨道结构动力响应会发生突变,导致系统动力响应超过限值。建立的基于移动单元法的有砟轨道-车辆耦合模型及相关分析可为高速铁路的振动分析提供参考依据。
To consider the shear effect of subgrade soil in the existing three-layer discrete supported beam for ballasted track model,the shear layer is discretized on the basis of Pasternak two-parameter foundation model.The moving element method is used to establish the ballasted track-vehicle coupling dynamics model considering the shear effect of subgrade soil.The moving element method is combined with MATLAB to compile the calculation program.Through MATLAB numerical calculation,the influence of subgrade shear effect on vehicle-rail coupling system and the influence of track irregularity and sleeper empty suspension on system dynamic characteristics are studied.The results show that when considering the subgrade shear effect,the displacement responses of rail,sleeper and ballast are all reduced in different degrees,and the phase difference between rail and ballast is gradually increasing,and the acceleration responses of the three are also obviously reduced.Their inhibition effects on acceleration responses are reduced from ballast to sleeper in turn,but the acceleration reduction of rail is greater than that of ballast,which has a certain,but not obvious,impact on wheel-rail contact force,and the reduction is only 0.85%.The irregularity amplitude and wavelength characteristics will have a significant impact on the dynamic response of the system.With the increase of the amplitude and shortwave component,the dynamic response of the system will be significantly improved,in which the shortwave irregularity of about 2 m and the 90th percentile spectrum will have a significant impact on the dynamic characteristics of the system.When the train passes through the unsupported sleeper area,the dynamic response of the track structure of the unsupported sleeper and the surrounding area will change suddenly,resulting in the system dynamic response exceeding the limit.The coupling model of ballasted track and vehicle based on moving element method and its correlation analysis established in this paper can provide reference for vibration analysis of high-speed railway.
作者
雷拓
魏鎏勇
凡尊军
徐龙祥
晋婷婷
LEI Tuo;WEI Liuyong;FAN Zunjun;XU Longxiang;JIN Tingting(School of Civil Engineering,Chang'an University,Xi'an 710061,China)
出处
《铁道标准设计》
北大核心
2024年第7期53-62,共10页
Railway Standard Design
基金
陕西省自然科学基础研究项目(2021JM-178)。
关键词
高速铁路
有砟轨道
移动单元法
路基剪切
轨道不平顺
轨枕空吊
high-speed railway
ballasted track
moving element method
subgrade shear
track irregularity
unsupported sleeper
