大轴力桩基托换监测分析

深圳市地铁一期工程百货广场大轴力桩基托换采用梁托换柱的结构型式,托换结构由托换大梁和两根支撑大梁的托换新桩组成,用主动托换方式,在托换大梁和新桩之间安装千斤顶,分级施加主动力。在托换的整个过程中对托换结构进行实时监测,通过反馈监测信息随时掌握托换结构和原建筑物的变形及受力状况,指导安全施工。分别用不同的测试仪测试原建筑物的沉降、梁板附加应力、梁柱接头的滑移,分析梁板附加应力、主动托换力的分配及荷载的转移规律,以及大梁的受力和变形状态。在托换新桩的桩顶垂直于梁轴线方向安装2个位移计,推测桩的沉降及大梁的偏转状况。将所有传感器集成一个自动测试系统,按照制定的监测控制标准,实施自动监测和安全控制。经过对第一根桩的全过程跟踪监测分析表明:托换结构和建筑物的变形及受力控制都在安全标准范围内;主动托换力保持在40%P时进行截桩,可使得托换前后柱的轴力变化和梁柱接头下沉达到最小。     

水火弯板温度场中相似性规律的研究

通过对水火弯板温度分布的实验数据及数值计算结果的分析，认为在加热线垂于板边且从板边形始加热的条件下，在垂直于板厚方向的各截面上的温度分布具有相似性，在同一截面上垂直于加热线方向的各直线上的温度分布具有相似性，进而根据这些相似性讨论了水火弯板温度场的半解析解的基本形式。     

Analysis of dynamic response of the high-speed EMS maglev vehicle/guideway coupling system with random irregularity

A new dynamic model of a high-speed EMS maglev vehicle/guideway interaction is presented. The model considers the vehicle and the guideway as an integral system and couples vertical interaction with lateral interaction. The vehicle subsystem is modeled as a multi-body system, which runs on the guideway with a constant velocity. The guideway substructure is modeled as an elastic beam. The attractive magnetic forces between vehicle and guideway are decided by controller, observer, and filter. A special simulation program is developed. Numerical results of the program are compared with test results. The results show that the coupling model is appropriate and the simulation program is credible primarily. Applications of coupling model to the investigation of the effect of irregularities on maglev system are reported at the end of the paper. The studies in this paper can be used to evaluate and optimize dynamic performances of the high-speed EMS maglev system.     

Consequences of Nonlinear Characteristics of a Secondary Suspension in a Three-Piece Freight Car Bogie

Mechanical systems with nonlinear characteristics can show a complex dynamic behavior that should be taken into account when analysing dynamic performance and reliability. The dynamic behavior of the main suspension in a three-piece freight car bogie with constant friction damping is considered in this work. The aim is to investigate the vertical behavior of a specific suspension design due to different driving conditions, weather and wear of the friction wedges. A variation in weather and wear is represented by different friction configurations in the model of the suspension. Models of different levels of detail that are based on experimental data on existing designs are developed. It is found that the suspension performance is very sensitive to variations of the friction configuration and this indicates a possible presence of nonlinear dynamic phenomena at in service like conditions.     

客运专线铁路隧道瞬变压力现场试验及单维效应分析

客运专线铁路隧道的设计与研究中必须要考虑高速列车在隧道中运行时所诱发的空气动力学效应的影响,其中应重点考虑瞬变压力对旅客乘车舒适度的影响。文章通过遂渝线提速(200 km/h)综合试验中的隧道空气动力及结构动力学试验,对200km/h动车组通过隧道时隧道内瞬变压力的现场试验数据及其单维效应进行了分析与研究。     

铁路数字调度通信系统基本功能检验

本文根据铁路运输调度通信的特点，提供了数字调度通信系统基本功能检验要求，检验配置及测试检验方法。铁路数字调度通信系统的检验和测试涉及多个方面，本文重点介绍铁路数字调度通信系统基本功能检验。包括调度交换设备单机功能检验、调度通信系统功能检验，同时结合铁路现场实际应用情况，介绍了不同型号数字调度系统间互联功能检测以及调度交换机系统与GSM—R系统间互联功能检验。     

UM71无绝缘轨道电路的模拟制作、联锁试验及故障查找

本文介绍了UM71无绝缘轨道电路模拟电路的制作和调试的方法和步骤,并对联锁关系和故障查找进行了分析。     

浅析广深线GSWJ98型信号微机监测系统

信号微机监测系统是保证行车安全，加强信号结合部管理，监测铁路信号设备运用质量的重要行车设备。针对广深铁路线上的GSWJ98型微机监测系统及其技术进行分析及探讨，为同类设计提供有益的参考。     

40Cr钢超高周疲劳性能及疲劳断口分析

采用超声疲劳试验方法研究40Cr钢在105周次～1010周次范围内的疲劳性能,其载荷频率为20kHz。用扫描电子显微镜分析了疲劳断口形貌特征。结果表明,40Cr钢的S N曲线始终保持下降趋势,且随疲劳循环数的增加,在106周次处并没有传统意义上的水平段;107周次疲劳强度为443MPa,1010周次疲劳强度为235MPa,二者存在明显差别;超声疲劳断口的扫描电子显微分析结果表明,40Cr钢超声疲劳断口显微形貌与常规疲劳载荷下的疲劳断口形貌无明显差异,疲劳裂纹在光滑试样表面或近表面材料缺陷处萌生,扩展区断口显微形貌观察到明显的疲劳辉纹。     

日本山梨磁悬浮试验线车辆用空调系统

山梨磁悬浮试验线车辆用空调系统既要适应列车以500km/h的高速运行,也必须解决应用于超导磁悬浮车辆时的其他特殊要求。文中介绍了JR东海公司开发的山梨磁悬浮试验线车辆用空调系统的概况及技术特征。