寒冷地区客车的防寒设计

根据25T型铁路客车在寒冷地区的运用,分析了列车防寒的主要因素,包括车体的密封性、防寒材料的薄弱部位和热绝缘等。结合运用结果,提出了寒冷地区列车防寒结构方案的改进设计。     

高速公路上跨桥整体顶升技术

该文通过工程实例介绍了整体顶升技术在某高速公路上跨桥桥梁净空改造中的应用。采用整体顶升技术对既有桥梁的净空不足问题进行改造,与拆除重建桥梁相比,可以节约工程造价、社会效应影响较小、工期较短、环境污染小。     

门架式双排抗滑桩研究现状和应用前景展望

针对普通抗滑桩的缺点,介绍一种新型抗滑桩—门架式双排抗滑桩,全面分析其现状和存在的问题,同时根据门架式双排抗滑桩的自身优点,对其应用前景作简要评述。     

CFG桩复合地基承载力的试验研究

利用静载试验分别确定CFG单桩和复合地基的承载力,并对其承载机理和特性进行了分析。     

一个重要的课题

同济大学交通运输工程学院城市轨道与铁道工程系承担了国家科技支撑计划项目"新型城市轨道交通技术"课题,其中之一的子课题为"轨道交通与土地利用的互动分析研究".     

成品油管道罐容优化计算

针对长输成品油管道顺序输送沿线各站罐容计算问题,特别是首站设立在原油加工企业,成品油在大部分通过长输管道外输并均匀补给首站时,指出了国家现行规范对罐容计算的不足,对标准提出的计算方法进行优化,减少成品油管道站场的储罐建设,降低站场用地,节约建设费用.以GB 50253-2003输油管道工程设计规范中罐客计算公式为基础,结合管道沿线各站的实际情况,进行优化计算.实例计算结果表明,按规范计算的罐容明显偏大.     

Multi-try counter-meshing gears discrimination device based on MEMS technology

A multi-try counter-meshing gears (CMG) discrimination device based on micro electromechani-cal system (MEMS) technology was designed for some specified information fields. The discrimination deviceconsists of two groups of metal CMG, two pawl/ratchet mechanisms, two driving micromotors and two re-setting micromotors, which make the CMG withdraw by raising the pawls. The energy-coupling element isa photoelectric sensor with a circular plate which is notched. Micromotor is fabricated using the ultravioletLiGA (UV-LiGA) fabrication process and precision mechanical engineering. The discrimination device has thefunction which can automatically reset, with the correct resetting code, it can be tried another times.     

Quantitative Analysis of impact of Bicycles on Vehicles in Urban Mixed Traffic

Bicycles create obvious impact on motor vehicles' behavior on urban road especially in China with mixed traffic. These influences can be divided into two states: friction and block interference. Based on the data of interference of bicycles on vehicles' driving in typical road section in Beijing, this paper quantitatively analyzes the velocity changing tendency of vehicles under different interference, velocity distribution frequency, and critical transformation of different interference state. The friction and block interference coefficients are also worked out, which are useful to compare interference degrees under different road conditions. As a result, the research based on sample data shows that the velocity distribution of vehicles has different characteristics under different interference state, and vehicles driving velocities are significantly different under the friction interference and block interference.     

连续配筋混凝土加铺层研究

介绍了旧水泥混凝土路面上连续配筋混凝土加铺层的结构型式、端部锚固结构以及施工技术,以为连续配筋混凝土路面在旧水泥混凝土路面加铺中的应用提供参考。     

8字结形格栅钢架腹筋力学作用试验研究

在山岭隧道复合式衬砌施工中,格栅钢架被广泛应用。为研究8字结形格栅钢架腹筋的力学作用,采用模型试验方法,设计一系列格栅钢架试件,系统地研究腹筋直径和焊缝长度对格栅钢架的力学作用影响。研究结果表明： 1）随着8字结腹筋直径的减小,喷混凝土格栅钢架极限承载力基本没有降低,但优化指数大幅度增大; 2）对于腹筋直径,只需满足格栅钢架加工、存放、运输和安装过程中主筋架立和固定的要求即可; 3）主腹筋焊缝长度的减小对格栅钢架的承载力基本没有影响,但可以大幅降低格栅钢架的制作成本。