车用电线束插接器端子正向力探讨

车用电线束插接器端子是决定插接器电力和信号传输性能的关键零件．端子的正向力是决定端子性能的一个重要因素。分析影响端子正向力的主要因素，探讨端子正向力对插接器机械性能、电性能及磨损寿命的影响。     

接触网的动态变化特性对改进施工的几点启示

接触网受气温、机车受电弓高速滑动和牵引电流剧烈波动等众多因素的影响,其状态时刻处在复杂的动态变化之中。这种动态变化直接影响接触网的质量稳定和运行安全。因此,在施工时不仅要确保接触网的静态参数满足标准要求,而且要保证这些参数的动态变化范围不超限。在分析接触网动态变化特性的基础上,提出了改进施工的几点启示,对提高接触网施工质量具有一定参考价值。     

生物接触氧化工艺中生物膜冲洗的研究

为确保生物接触氧化工艺稳定、良好的工作状态，减小对后续常规工艺处理效果的影响，根据生物膜活性的特性变化，对工艺工作周期、冲洗指标、冲洗方法和控制参数进行探讨。结果表明：生物膜冲洗可由出水NH3-N浓度、NH3-N去除率及运行时间来确定，冲洗方法应以局部冲洗为宜，即间隔3～5天，历时10—15min、强度0．6～0．7m^3·（min·m^2）^-1，对每格池的四分之一区域进行冲洗。     

Research into the problem of wheel tread spalling caused by wheelset longitudinal vibration

This study mainly focuses on the mechanism of wheel tread spalling through wheelset longitudinal vibration that has been often neglected. Analysis of two actual cases of the wheel tread spalling problem leads to the conclusion that the wheel tread spalling is closely related to the wheelset longitudinal vibration in some locomotives, and many of these problems can be reasonably explained if the wheelset longitudinal vibration is considered. For better understanding of some abnormal wheel spalling problems, the formations of the wheelset longitudinal vibration and the wheel/rail contact parameters were analysed in the initial wheel tread spalling. With the preliminary analytical results, the wheelset longitudinal dynamic behaviour, the characteristics of wheel/rail contact and the mechanics in the condition of the wheelset longitudinal vibration were further studied quantitatively. The results showed that the wheelset longitudinal vibration changed not only the limit of these parameters and the position of principal stress, but also the direction of the principal stress on the surface of wheel/rail contact patch. It is likely that the significant stress changes provoke too much stress on the surface of wheel/rail contact patch, cause fatigue in wheel/rail contact patch and eventually lead to wheel tread spalling. The results of these studies suggest that the suppression of the wheelset longitudinal vibration extends wheel/rail life and the addition of a vertical damper with an ahead angle provides a possible solution to the wheel spalling problem.     

接触线及承力索终锚线夹的改进探讨

通过对传统使用的GLCN250接触线终锚线夹及接头线夹、LBGLJ185终锚线夹及接头线夹存在问题的探讨,对终锚线夹提出了减小楔子的锥度,在楔子内表面加工内螺纹,加宽空心楔子开槽宽度等改进措施。     

高速机车牵引齿轮强度的试验研究

对美国和国产要车牵引齿轮进行了强度试验分析，认为只要适当优选材料和工艺，国产机车牵引齿轮要以取代美国的牵引齿轮。     

The vertical and the longitudinal dynamic responses of the vehicle–track system to squat-type short wavelength irregularity

The squat, a kind of rolling contact fatigue occurring on the rail top, can excite the high-frequency vehicle–track interaction effectively due to its geometric deviations with a typical wavelength of 20–40 mm, leading to the accelerated deterioration of a track. In this work, a validated 3D transient finite element model is employed to calculate in the time domain the vertical and the longitudinal dynamic contact forces between the wheel and the rail caused by squats. The vehicle–track structure and the wheel–rail continua are both considered in order to include all the important eigencharacteristics of the system related to squats. By introducing the rotational and translational movements of the wheel, the transient wheel–rail rolling contact is solved in detail by a 3D frictional contact model integrated. The contact filter effect is considered automatically in the simulations by the finite size of the contact patch. The present work focuses on the influences of the length, width and depth of a light squat on the resulted dynamic contact forces, for which idealised defect models are used. The growth of a squat is also modelled to a certain extent by a series of defects with different dimensions. The results show that the system is mainly excited at two frequencies separately in the vertical and the longitudinal dynamics. Their superposition explains the typical appearance of mature squats. As a squat grows up, the magnitude of the excited vibration at the lower frequency increases faster than the one at the higher frequency.     

小间距双线隧道CRD法零距离下穿既有营运车站变形影响研究

以深圳地铁7号线皇岗村站至福民站的新建小间距双线平顶隧道施工区间工程为例,研究采用"CRD法+直墙暗挖"进行零距离下穿既有4号线福民站,对其结构变形影响及现场监测结果分析。通过对新建双线隧道施工全过程的精细化数值仿真模拟,揭示既有营运车站的变形规律,为施工过程中结构变形发展预测和设计方案实时调整提供理论支撑。结合施工过程实时监测资料,论证新建隧道下穿施工对既有车站的影响程度,验证当前设计方案的可行性。结果表明,数值仿真分析的既有车站变形规律与实际监测结果一致,且最大变形量均小于控制值10.0 mm。     

减摇鳍执行机构非线性接触有限元分析

减摇鳍的执行机构是减摇鳍装置完成收放及减摇功能的核心部件,也是鳍翼面升力与阻力的主要传力部件.采用Patran/Nastran对某收放式减摇鳍执行机构进行三维非线性接触有限元计算,确定其应力应变场,为其优化及改进提供设计依据.