轨枕空吊条件下列车-轨道-箱式路基动力响应分析毕业论文
2021-10-26 21:57:21
摘 要
近年来,我国铁路事业发展迅速,在高速铁路等技术上取得了重大进步。但是,随着列车行驶速度的不断提高,铁路系统中各个构件的振动也在不断加剧,特别是当轨道结构中存在“轨枕空吊”现象时,构件的振动将更加剧烈。国内外许多学者基于传统路基形式对由轨枕空吊引起的有砟轨道的动力响应进行了研究,但对箱式路基却鲜有关注。
本文为探究轨枕空吊条件下列车-轨道-箱式路基的动力响应情况,分别建立了列车子系统模型和轨道—箱式路基子系统模型,其中列车子系统模型采用具有二系悬挂的多刚体系统进行模拟,轨道—箱式路基子系统模型运用ANSYS软件建立有限元模型,采用线性赫兹轮轨接触将两个子系统进行耦合,通过删除道砟弹簧阻尼和引入非线性道砟弹簧阻尼来模拟轨枕完全空吊和非完全空吊两种空吊状态,利用分离迭代法进行计算求解并使用MATLAB软件编程实现,分析了轨枕空吊数量、列车行驶速度、轨枕空吊间隙以及轨道高低不平顺等因素对耦合系统的动力影响,并研究了轨枕空吊沿轨道纵向的影响范围。研究结果表明:
(1)在轨枕完全空吊条件下,空吊轨枕数量和列车行驶速度都会对耦合系统的动力响应产生影响。空吊轨枕数量越多,列车行驶速度越大,钢轨和轨枕的振动就越剧烈,但对于车体和箱式路基的影响十分有限。在非完全空吊条件下,空吊间隙对于系统的振动加速度有很大影响。
(2)轨道高低不平顺和轨枕空吊不平顺两者共同作用下比它们单独作用下的动力响应大,轨道高低不平顺会加速轨枕空吊的发展,轨枕空吊也会加剧轨道线形的恶化。
(3) 轨枕空吊对其附近1~2个轨枕位置处的轨道结构构件的动力响应有较大的影响,容易导致其毗邻轨枕的松动,加剧轨枕空吊现象的发展。
关键词:轨枕空吊;箱式路基;动力响应;分离迭代法;耦合系统
ABSTRACT
In recent years, with the rapid development of China's railway industry, great progress has been made in the technology of high-speed railway. However, with the increase of the train speed , the vibration of components in the railway system is also increasing. And if there are unsupported sleepers in the track structure, the vibration of components will be more violent. Many scholars around the world have studied the dynamic responses of ballasted track caused by unsupported sleepers based on the traditional subgrade form, but little attention has been paid to the box subgrade.
In order to study the dynamic responses of the train-track-box subgrade system in the condition of unsupported sleepers, the train subsystem model is simulated by multi-rigid-body system with two suspensions and the track-box subgrade subsystem model is established by finite element model in ANSYS software, respectively. The two subsystems are coupled by linear Hertz wheel-rail contact, and the complete unsupported sleepers and incomplete unsupported sleepers are simulated by deleting ballast spring-damper system and introducing nonlinear ballast spring-damper system. The separation and iteration method is used to calculate the results by MATLAB programs. The influence of the number of unsupported sleepers, the speed of the train, the suspension gap of unsupported sleepers and the irregularity of the track on the dynamic responses of the coupling system is analyzed, and the influence range of the unsupported sleepers along the longitudinal direction of the track is studied. The results show that:
(1) When the sleepers are completely unsupported, the number of unsupported sleepers and the speed of the train will affect the dynamic responses of the coupling system. The more the number of unsupported sleepers and the speed of the train, the more violent the vibration of the rails and sleepers, but the effect of unsupported sleepers on the car body and box subgrade is very limited. When the sleepers are incompletely unsupported, the suspension gap of unsupported sleepers has a great influence on the vibration acceleration of the system.
(2) Under the combined action of track irregularity and unsupported sleeper, the dynamic responses are greater than that under their separate action. Track irregularity will accelerate the development of unsupported sleepers, and unsupported sleepers will also aggravate the deterioration of track alignment.
(3) The unsupported sleepers have a great influence on the dynamic response of the track components in the range of 1-2 sleeper spacing, which may lead to the loosening of the adjacent sleepers and aggravates the development of the phenomenon of unsupported sleeper.
Key Words: unsupported sleepers; box subgrade; dynamic responses; the separation and iteration method; coupling system
目 录
第1章 绪论 1
1.1 研究的背景及意义 1
1.1.1 我国高速铁路发展现状 1
1.1.2 新型“箱式路基”结构 2
1.1.3 “轨枕空吊”病害 2
1.2 轨枕空吊研究现状 3
1.3 本文的研究内容 5
第2章 列车-轨道-箱式路基耦合动力学模型 7
2.1 列车模型 8
2.2 轨道—箱式路基模型 10
2.3 轮轨接触模型 13
2.4 轨枕空吊模型 14
2.4.1 完全空吊模型 14
2.4.2 非完全空吊模型 15
2.5 本章小结 16
第3章 列车-轨道-箱式路基耦合系统的求解 17
3.1 分离迭代法 17
3.2 耦合系统运动方程 19
3.3 Newmark-β数值积分法 21
3.4 本章小结 23
第4章 轨枕空吊条件下系统动力响应分析 24
4.1 计算工况 24
4.2 参数分析 25
4.2.1 轨枕空吊数量的影响 25
4.2.2 列车行驶速度的影响 30
4.2.3 轨枕空吊间隙的影响 33
4.3 轨道高低不平顺的影响 38
4.4 轨枕空吊沿轨道纵向的影响 41
4.5 本章小结 43
第5章 结论与展望 44
5.1 结论 44
5.2 展望 45
参考文献 46
致谢 48
绪论
研究的背景及意义
我国高速铁路发展现状
铁路运输作为我国旅客运输的主要方式[1],是交通运输体系中的重要组成部分。其中高速铁路因其运输能力强、运行速度快、安全性高、舒适性好以及低碳环保等特点,在社会经济发展中占据着重要地位,近年来得到了飞速发展。从上世纪90年代开始,中国就开始在高速铁路领域进行研究探索,并取得了重大进步。
1990年,铁路主管部门正式立项,下达了“中国高速铁路发展模式和规划的研究”科研课题,我国正式开始了对高铁技术的研究。1994年,广深准高铁投入运营。2003年,我国建成了第一条铁路客运专线—秦沈客运专线,全长404.6公里,设计时速最高可达250km。2004年我国通过了《中长期铁路网规划》,确定了中国高铁发展的“四纵四横”快速客运网络图。2008年,我国第一条设计时速达350km的京津城际高速铁路正式通车,成为了当时世界上运营时速最高的高速铁路。2010年2月,世界上首条修建在湿陷性黄土地区的郑西高速铁路开通运营。同年12月,CRH380A型动车组在京沪高铁试验段上创下时速486.1km的世界铁路运营试验最高速度纪录。之后,沪宁高铁、沪杭高铁、京沪高铁等高速铁路先后建成通车。2017年,“复兴号”中国标准动车组以时速350km在京沪高速铁路商业运营,树立了世界高铁建设运营新标杆。