利用多种测试手段全面解析广东某高速公路沥青路面车辙

通过采用激光车辙测量系统LRMS、落锤式弯沉仪FWD等多种现代测试方法对广东某高速公路沥青路面典型路段的车辙状况及使用性能进行了现场测试,并结合路面沥青混合料的动态三轴压缩蠕变、GTM旋转剪切压实等室内试验结果分析,准确查找了路面车辙病害产生的原因,为该道路养护维修处治方案的制定提供了依据。     

不同评价方法在电气检测实验室内部质量监控中的应用

实验室内部质量监控常用的评价方法有归一化误差(|En|值)法、z比分法和t检验法.针对电气检测中最常用的电压检测,分别采用3种评价方法分析检测结果,探讨3种方法的差异和适用范围.结果显示,3种方法对此次比对结果的分析结论基本一致,在实际应用中应根据样品特点和比对目的选择合适的评价方法.     

Virtual hull monitoring of a naval vessel using hindcast data and reconstructed 2-D wave spectra

A novel virtual hull monitoring approach is assessed using full-scale measurements from a naval vessel trial to address two questions. First: Can this technique accurately reproduce stress spectra from measured strains? Second: Are responses calculated using reconstructed two-dimensional wave spectra from hindcast data more accurate than those using simpler wave representations? Stresses calculated using wave hindcast data, ship track information, and stress transfer functions compare favorably to those derived from strain gauge measurements at five structural locations. Wave conditions are represented using a spectrum model along with bulk spectral parameters (significant wave height, peak period, and primary direction) from hindcast datasets and by reconstructing two-dimensional spectra from hindcast partition data. Both approaches give good agreement with strain measurements but using the more-detailed reconstructed two-dimensional wave spectra yields better results. Results suggest that wave hindcast data are sufficient for accurate structural calculations, encouraging further study of virtual hull monitoring using wave hindcast data.     

汽车螺纹紧固扭矩与检验扭矩关系验证

为了确保整车扭矩的安全性与可靠性,对不同连接状态的紧固扭矩和检验扭矩进行验证,以更好地控制整车扭矩.确定检验用数显扭力扳手的最佳量程,在最佳量程内采集紧固扭矩和检验扭矩,并进行线性分析,预测不同连接状态的关系趋势。结果表明,6种不同连接状态的紧固扭矩和检验扭矩存在不同的对应关系。整车厂应区分紧固扭矩和检验扭矩,并确定不同连接状态对应的关系,以更好地保证整车扭矩质量。     

车辆操纵稳定性对比试验研究

通过对同一车型的两个不同厂家的车辆进行操纵稳定性的试验对比,测试同一状态下车辆的操纵稳定性数据,用三种试验方法获得的试验数据进行了对比,最终选择了最优的一组车辆结构参数.     

Testing and Approval Procedures for New Slab Track Systems in Europe

This paper describes the required testing and approval procedures of new track systems operated in Europe. To begin with, test methods and performance specifications according to European Standard (EN) are outlined. These include the repeated loading test, the determination of the static and dynamic stiffness of rail pads, clamping force and longitudinal rail resistance. The fact that labor tests are unable to simulate all the conditions in situ shows that these labor tests are not sufficient for the evaluation of the long term behaviour of a new track system: a test track of sufficient length must be constructed and exposed to traffic loads. In Europe to be accredited as a new system, a new slab track system must have a trial time of more than two years, during which the features of the whole system can be recognized. In the second part of this paper, the experience of the Institute of Road, Railway and Airfield Construction of TUM concerning the measuring methods of slab track systems carrying traffic are outlined. Also the approval procedure of the new slab tracks in Germany is discussed.     

汽车生产过程中的防错法

为了避免汽车制造厂生产过程中出现的一些缺陷,也为了降低汽车生产过程中各个环节额外增加的制造费用,各汽车生产厂商都已经采用了防错法。防错法代替了针对缺陷制定的一些改进措施,可以避免一些不必要的制造缺陷,而且可以避免在生产中各个环节额外增加的费用,降低生产成本。通过实践证明,在制造环节采用防错法,可以实现零缺陷。     

燃料电池发动机测控系统控制平台开发

基于MATLAB／SIMULINK／S1ATEFLOW软件平台,结合dSPACE的软硬件资源,开发出了燃料电池发动机测控系统的控制平台。在燃料电池发动机测试规范的基础上,该平台实时地实现了发动机的工况管理、基于CAN总线的各部件节点的协调控制、自动和手动测试及无缝切换、测功机负载控制、故障诊断和处理及数据记录等功能,顺利完成了燃料电池发动机的测试。     

主动油气悬架试验模型的研制

文章重点介绍了一个二自由度主动悬研制情况。该模型于１９９７年１０月在清华大学汽车工程系统建成，成功地进行了多种主动悬架控制策略的试验和验证工作得到了较好的结果，为后续研究工作的顺利进行提供了良好的试验手段。     

高性能Al10Sn3SiCu轴瓦带材的制造技术

通过高性能轴承合金Al10Sn3SiCu的开发,基本掌握了含硅的铝锡轴承合金全套生产技术。应用现有的熔铸及轧制生产设备,通过工艺的优化与调整,瓦带的轧制成材率达到93%以上,蓝宝石疲劳强度和国外同类产品相当。