上行式SX64/2700型移动支架造桥机预压试验监测及分析

为保证桥梁施工质量和安全,移动支架造桥机首次使用前必须进行预压试验。以西成客运专线汉江特大桥为工程背景,介绍上行式SX64/2700型移动支架造桥机预压试验的有限元分析、测点布置、监测方法及频次。通过对预压过程的监测和对监测数据的分析,计算出了弹性变形和非弹性变形,取得了应力实测数据,证明上行式SX64/2700型移动支架造桥机完全能够满足该桥的施工要求。     

不同车流对桥梁静三分力及局部风压影响的风洞试验研究

在风-车-桥耦舍系统中,不同交通状态车辆将引起桥梁气动力和局部风压的变化。采用测压法测试了不同车流下桥梁断面三分力系数随攻角的变化情况,研究了不同车流下车辆对三分力系数以及局部风压的影响。研究结果表明：在堵车情况下车辆对桥梁断面三分力影响最大,车辆引起桥梁阻力系数和升力矩系数显著减小,使升力系数增大。在车桥耦舍风场作用下,桥梁顶面迎风侧压力值产生由正到负的剧烈幅值变化。     

某型地铁车辆用带轴承座的传动齿轮箱

文章介绍了一种自主研发的带有轴承座结构的齿轮箱,并对其结构布置、齿轮设计、强度分析、润滑与密封系统等进行了详细分析。结果表明,自主研制的地铁车辆用齿轮箱性能完全符合我国城市轨道交通的运用要求,可广泛应用于我国地铁车辆。     

装有关节轴承的牵引销结构改进

双侧平拉杆牵引装置中的牵引销易锈蚀、磨损,情况严重时导致牵引销无法拆卸。文章主要从结构、润滑、表面处理、保养等方面介绍如何对其进行改进。改进后的牵引销不易生锈,且拆卸容易,达到了预期的效果。     

SZS3081型双线润滑系统在汽车底盘集中润滑系统中的应用

Wang Xiongjian;Liu Jie(Zhejiang Sanlang Lubrication Technology Co.,Ltd.Ningbo 315700)     

桩土相互作用的砂箱模型试验及计算分析

提出了用有限元-无界元耦合的方法计算大变形条件下桩-土耦合体系的应力和变形．在桩与土接触的界面上设置了一种有厚度的接触面单元，它可以与土体的弹塑性模型相衔接，能合理地反映接触面及其邻近区域剪切破坏带中的变形性状．计算结果与现场观测数据吻合较好，说明该计算方法是可行的．     

竖向荷载下超大群桩受力变形分析

根据模型试验研究结果，分析了在竖向荷载作用下超大群桩基础的荷载传递特点、群桩的承载性关和桩侧摩阻力的发挥特性。试验结果表明。在本试验条件下，荷载在桩间的分配，最终以中心部分桩受到的荷载量大；桩身下部轴力明显小于上部轴力；随荷载的增加，桩身侧摩阻力由下部先行发挥并逐步向上发展。     

伊春大桥静载试验与结构评定试验研究

通过对伊春大桥静载试验研究,检验桥跨结构的实际承载能力、结构变形及使用性能是否满足设计要求,了解结构的实际受力状况和工作状况,为日后运营、养护及管理提供科学依据;通过静载试验,建立该类桥梁有关的技术档案,为今后兴建同类桥梁完善设计、优化结构、改进工艺积累实测资料.     

应用共振频谱测定结构材料疲劳损伤剩余强度的试验研究

本文对自然条件相同的一组结构材料进行了等幅加载和变幅加载试验,测定了试件在各个承载阶段内的共振频谱.结果发现:被测试件从开始状态到疲劳断裂的各个阶段都有其表示疲劳状态的、特定的对应共振频谱.     

Switch Panel wear loading – a parametric study regarding governing train operational factors

The acting forces and resulting material degradation at the running surfaces of wheels and rail are determined by vehicle, track, interface and operational characteristics. To effectively manage the experienced wear, plastic deformation and crack development at wheels and rail, the interaction between vehicle and track demands a system approach both in maintenance and in design. This requires insight into the impact of train operational parameters on rail- and wheel degradation, in particular at switches and crossings due to the complex dynamic behaviour of a railway vehicle at a turnout. A parametric study was carried out by means of vehicle-track simulations within the VAMPIRE® multibody simulation software, performing a sensitivity analysis regarding operational factors and their impact on expected switch panel wear loading. Additionally, theoretical concepts were cross-checked with operational practices by means of a case study in response to a dramatic change in lateral rail wear development at specific switches in Dutch track. Data from train operation, track maintenance and track inspection were analysed, providing further insight into the operational dependencies. From the simulations performed in this study, it was found that switch rail lateral wear loading at the diverging route of a 1:9 type turnout is significantly influenced by the level of wheel–rail friction and to a lesser extent by the direction of travel (facing or trailing). The influence of other investigated parameters, being vehicle speed, traction, gauge widening and track layout is found to be small. Findings from the case study further confirm the simulation outcome. This research clearly demonstrates the contribution flange lubrication can have in preventing abnormal lateral wear at locations where the wheel–rail interface is heavily loaded.