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561.
为选择适合我国到发线的无砟轨道结构,在无砟轨道再创新的基础上,结合发线无砟轨道结构的技术特点及技术要求,提出框架梁式无砟轨道。它是一种适合高速铁路桥上车站到发线的新型无砟轨道形式,自下而上依次由底座板、预制框架梁、锚固支承结构、扣件、钢轨组成。在充分考虑框架梁式无砟轨道结构系统特点、受力机理基础上,利用有限元法,建立了框架梁式无砟轨道结构的静动力学分析模型,考虑在列车荷载、温度荷载及桥梁挠曲荷载组成的不同工况作用下,对所设计的不同框架梁与底座板的锚固支承结构方案进行对比分析。研究结果表明:静力计算抗剪销+5对胶垫方案最优,L型支座+5对胶垫方案次之,抗剪销+CA砂浆方案最差,但这3种方案相差不大。 相似文献
562.
高速移动荷载作用下CRTSⅡ型板式无砟轨道基础结构动应力分布规律 总被引:5,自引:0,他引:5
运用ANSYS软件,建立路堤上的CRTSⅡ型板式无砟轨道基础结构的动力有限元模型,研究不同速度移动荷载作用下轨道和路基动应力的分布和传递规律。结果表明:在不同的轨道和路基层内动应力沿横向的分布规律与移动载荷的速度相关性不大,而与各层距钢轨底面的距离关系很大;轨道板应力沿横向呈驼峰形分布,最大值位于钢轨正下方,钢轨之间应力水平基本一致;路基动应力随深度的增加,在距离钢轨底面1m范围内急速衰减,在1~4m范围内基本呈线性快速衰减,超过4m后衰减较为缓慢;不同位置的路基动应力总体上随着移动荷载速度的增加而增大,在80~350km·h-1的车速范围内具有较为明显的线性关系,而当速度小于80km·h-1或者大于350km·h-1时变化不明显。 相似文献
563.
564.
无缝线路模型轨道的流变特性实验 总被引:3,自引:0,他引:3
通过对模型轨道的实验,验证了无缝线路(CWR)流变理论模型的正确性,并为将来进行实物轨道的流变特性实验提供了具体步骤和确定流变理论参数的方法。 相似文献
565.
无碴轨道谐振式无绝缘轨道电路传输距离的缩短,直接影响行车安全。为达到延长轨道电路传输长度的要求,通过分析和计算对电气绝缘节在轨道电路中损耗进行了研究。 相似文献
566.
跨座式单轨PC轨道梁为"梁轨合一"结构,线路的平、竖曲线、横向超高以及预拱均在一次浇筑的梁体上实现,其线形及精度直接决定着列车行驶的舒适性.芜湖市单轨项目在国内无成熟经验可借鉴的情况下创新施工方案,设置直曲线梁专用生产线、研发智能三维可调节模板、研究线形动态控制方法,得以成功制造出高标准的轨道梁,并总结出成熟的工艺及方法,具有推广价值. 相似文献
567.
H. Abel R. Clauß A. Wagner G. Prokop 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(9):1297-1320
The lateral vehicle dynamics is defined by the effects of side forces at the front and rear axle. These forces are caused by the slip and camber angle at the individual tyres, which are results of the kinematics and compliances of the chassis. This paper extends the approach of the effective axle characteristics by Paceyka to the analytical expression of the axle cornering stiffness and the axle relaxation behaviour with the aim of the development of a chassis design process as it applies in the early design stage. The obtained expression is integrated into a single track model and validated against a full nonlinear two-track model. By this means of these analytical expressions for the axle cornering stiffness and the axle relaxation behaviour it is possible to directly calculate and analyse the effective slip angles for linear quasi-static and dynamic driving manoeuvres. 相似文献
568.
Lei Xu Jianmin Gao 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(11):1686-1706
Track irregularities are inevitably in a process of stochastic evolution due to the uncertainty and continuity of wheel–rail interactions. For depicting the dynamic behaviours of vehicle–track coupling system caused by track random irregularities thoroughly, it is a necessity to develop a track irregularity probabilistic model to simulate rail surface irregularities with ergodic properties on amplitudes, wavelengths and probabilities, and to build a three-dimensional vehicle–track coupled model by properly considering the wheel–rail nonlinear contact mechanisms. In the present study, the vehicle–track coupled model is programmed by combining finite element method with wheel–rail coupling model firstly. Then, in light of the capability of power spectral density (PSD) in characterising amplitudes and wavelengths of stationary random signals, a track irregularity probabilistic model is presented to reveal and simulate the whole characteristics of track irregularity PSD. Finally, extended applications from three aspects, that is, extreme analysis, reliability analysis and response relationships between dynamic indices, are conducted to the evaluation and application of the proposed models. 相似文献
569.
I. S. Apezetxea X. Perez C. Casanueva A. Alonso 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(7):1071-1097
In railway applications wear prediction in the wheel–rail interface is a fundamental matter in order to study problems such as wheel lifespan and the evolution of vehicle dynamic characteristic with time. However, one of the principal drawbacks of the existing methodologies for calculating the wear evolution is the computational cost. This paper proposes a new wear prediction methodology with a reduced computational cost. This methodology is based on two main steps: the first one is the substitution of the calculations over the whole network by the calculation of the contact conditions in certain characteristic point from whose result the wheel wear evolution can be inferred. The second one is the substitution of the dynamic calculation (time integration calculations) by the quasi-static calculation (the solution of the quasi-static situation of a vehicle at a certain point which is the same that neglecting the acceleration terms in the dynamic equations). These simplifications allow a significant reduction of computational cost to be obtained while maintaining an acceptable level of accuracy (error order of 5–10%). Several case studies are analysed along the paper with the objective of assessing the proposed methodology. The results obtained in the case studies allow concluding that the proposed methodology is valid for an arbitrary vehicle running through an arbitrary track layout. 相似文献
570.
Zaigang Chen Wanming Zhai Kaiyun Wang 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(2):244-267
A gear transmission system is a key element in a locomotive for the transmission of traction or braking forces between the motor and the wheel–rail interface. Its dynamic performance has a direct effect on the operational reliability of the locomotive and its components. This paper proposes a comprehensive locomotive–track coupled vertical dynamics model, in which the locomotive is driven by axle-hung motors. In this coupled dynamics model, the dynamic interactions between the gear transmission system and the other components, e.g. motor and wheelset, are considered based on the detailed analysis of its structural properties and working mechanism. Thus, the mechanical transmission system for power delivery from the motor to the wheelset via gear transmission is coupled with a traditional locomotive–track dynamics system via the wheel–rail contact interface and the gear mesh interface. This developed dynamics model enables investigations of the dynamic performance of the entire dynamics system under the excitations from the wheel–rail contact interface and/or the gear mesh interface. Dynamic interactions are demonstrated by numerical simulations using this dynamics model. The results indicate that both of the excitations from the wheel–rail contact interface and the gear mesh interface have a significant effect on the dynamic responses of the components in this coupled dynamics system. 相似文献