Dynamic response of a double-lined shield tunnel to train impact loads

A three-dimensional numerical finite element model was established by Abaqus to study the time-history curves of train-to-tunnel impact forces for impacts at different velocities, train configurations and oblique-impact angles. A concrete plastic-damage model was used to study the dynamic responses of a double-lined shield tunnel to train impacts by the HHT time-integration scheme. Model simulations showed that the impact force was related to the velocity and angle of the train at impact, as well as the train configuration. Two categories of characteristic force vs. time curve were found for the train-to-tunnel impact, and multi-peak Gaussian fitting was used to interpret the first category. The dynamic response increases with greater impact velocity and impact angle, while it greatly reduces when the thickness of the secondary lining is increased. Most of the tensile damage was seen ahead of the impact point (in the direction of travel), and compressive damage was concentrated behind, above and below the impact point. The average maximum tensile damage was found to exceed the compressive damage.     

司机操纵评判系统的设计

提出以监控装置为数据源,建立数据库,然后通过绘制图形来进行操纵分析评定以及综合分析和操纵优化,既提高了检查人员的工作效率,又可以规范管理,提高机车乘务员的操作水平,给机务部门工作带来方便。     

内燃机配气机构ADAMS虚拟样机技术研究

利用虚拟样机技术进行发动机开发是发动机现代设计方法之一，其重点是建立开发系统的计算机虚拟样机模型。作者使用世界上应用最广泛和最具权威的机械系统动力学仿真软件ADAMS(Automatic Dynamic Analysis of Mechanical Systems)，并以某高速柴油机的配气机构为例，建立和测试了该机构的虚拟样机，实现了机构开发初期无物理样机条件下在计算机上仿真分析该机械系统的运动性能。     

温州动车追尾事故与CTCS-2技术规范中的安全隐患

2011年7月23日在温州附近不幸发生动车追尾，本文指出列控技术规范的变化可能同事故有关系。CTCS-2列控技术规范2007年版中引入了“三点检查”技术，理论上它能够在轨道电路故障情况下保障列车安全运行。如果在7月23日的故障状态下采用这一技术，调度可以在故障路段放入多辆列车，某些故障路段可能亮绿灯让列车正常通过，该技术将通过防护点保障安全。可能由于技术不够成熟的原因，CTCS-2技术规范2010年版中删除了这一措施，在新增的故障处理条款中没有明确说明设备故障需要亮红灯。如果此后调度按照过去的方式处理，很可能发生事故。     

发动机凸轮升程光顺时不同方法的应用

简要介绍了曲线光顺时的圆率法，回弹法及磨光法。比较了不同光顺方法对发动机配气凸轮升程曲线拟合的影响。给出了凸轮升程用圆率法和隔点差分比较法进行预光顺，用回弹法和磨光法进行精光顺后构造凸轮型线的计算实例。     

包装工程教育的探索与思考

文中论述了包装工程的学科特点和主攻专业方向，分析了该学科专业人才应具备的知识结构和教学的课程体系，提出了对人才培养过程的一些思考和建议。     

车轮踏面擦伤动态定量测量新方法

车轮踏面擦伤是危及列车运行安全的主要原因之一。如何准确测量其大小是高速和重载列车发展中必须首先要解决的关键测量问题。提出一种新的车轮擦伤动态测量方法，不仅能实现对踏面擦伤和磨损的定量测量，同时能克服已有技术测量不能定量、测量结果受外界很多因素影响的缺点。测量系统主要由平行四边形机构、传感器、数据采集与处理等部分组成。现场试验表明：当列车速度低于１５　ｋｍ·ｈ－１，系统的测量误差小于０．２　ｍｍ。     

陶瓷配气机构的研制

阐述了在６１０５柴油机上开发应用陶瓷配气机构零件的设计计算和试验研究情况，以及对陶瓷插柱和摇臂走向实用化、商品化的展望。并反映了我国近年来这方面工作达到的水平和存在问题。     

采用磁场分割法进行的发动机电磁气门驱动(EVA)仿真计算

在对发动机电磁气门驱动(E1ectromagnetic Valve Actuation，简称EVA)进行的仿真计算中，采用磁场分割法建立了电磁铁磁路模型，并根据牛顿第二定律和电压平衡原理分别建立了EVA动力学模型和电路模型，编制了相应的计算程序。计算与试验对比基本符合的情况表明，所建模型反映了EVA的基本特征，整套仿真方法可行。     

Optimised loading patterns for intermodal trains

This paper considers one important aspect of operations planning referred to hereafter as train planning. Train planning is the process of spatially assigning containers to specific wagons (also known as railcars) on an intermodal train. The spatial arrangement of containers on a train can have a significant influence over the amount of time and energy consumed in the handling of containers. Efficient train planning can also maximise utilisation of wagon carrying capacity. This study proposes a mixed-integer programming model to determine the arrangement of containers on a train to minimise a weighted sum of number of wagons required and equipment working time. Due to the large number of variables, the proposed model cannot be solved in a timely manner for practical problems. This is addressed by applying heuristic algorithms local search and simulated annealing. Discrete-event simulation of an intermodal terminal is used to evaluate the proposed methods and to illuminate various properties of the model.