环形立交异形板电算分析及工程应用

在城市道路"十"字路口路段,互通式环形立交异形板多有应用。环形立交异形板结构受力非常复杂,较难通过手算解决工程应用问题。通过对某桥环形立交异形现浇板进行有限元建模分析及工程应用,可为此类工程结构分析及应用提供参考。     

基坑围护结构施工技术

以重庆轨道交通六号线一期冉家坝车站基坑围护结构施工为例,详细研究明挖车站基坑围护结构的岩石、土壤及水文地质情况以及主要施工影响因素,通过研究悬臂式挡墙、板肋挡墙、桩板挡墙在施工中的应用,提出相应的施工方案及技术解决措施。研究表明:合理组织科学有效的施工方案能安全高效的做好基坑维护工作,对工程结构安全稳定有着重要意义。     

预应力现浇箱梁施工技术探讨

通过对现浇连续箱梁的施工过程的详细分析,总结并提出现浇连续箱梁施工控制的方法和措施,可供同行参考。     

碎石撒布板扩宽技术分析

对悬挂式石料撒布机进行了系统分析,导出了料槽滑落角与石料撒布板扩宽尺寸有关参数的关系,提出了当石料与撒布板的摩擦角等于料槽滑落角时,撒布宽度为＂撒宽极限＂的理论为了尽可能地增大撒布宽度,提出了将撒布板的安装仰角设为0°,并引入了带有封闭料槽结构的新型石料撒布装置     

大型客车仪表板开发

结合欧洲大型客车的发展趋势,阐述大型公路客车和城市客车仪表板设计上的区别;详细介绍大型客车仪表板的开发流程及设计考虑因素。     

汽车与高速公路指示牌碰撞研究

汽车与高速公路指示牌的碰撞是极其危险的事故。本文从高速公路交通事故的统计资料出发。分析了汽车与高速公路指示牌碰撞事故原因,利用有限元方法对汽车碰撞半刚性护栏与指示牌进行仿真模拟试验,根据研究结果进一步提出改进设计的方法。从而降低事故对车内乘员的伤害程度。     

竹园大桥西引桥裂缝原因分析与加固

文中分析了竹园大桥西引桥异形板沿行车方向产生裂缝的原因,提出加固处理方法,并提出防治裂缝的措施。     

沥青混合料拌和设备加热滚筒提料板结构分析与改进

针对韩国产TSAP2000型沥青混合料拌和设备在使用多年后加热滚筒热效率、生产率低下的问题,在设备装配、制造原因等方面进行了较全面的分析,对提料板技术改造提出了可行性方案,从理论和实践上进行了验证。技术改造后的TSAP2000型沥青混合料拌和设备在高速公路新建和维护中取得了良好的经济效益。     

常见盾构刀盘型式及选用

目前常见的刀盘结构有面板式和辐条式2种基本型式,以及介于2者之间的幅板式刀盘。通过文献分析和工程经验总结,首先阐述了几种型式刀盘的结构、基本配置及工程应用。随后从刀盘土舱构造、开挖面稳定、土压平衡控制、砂土的流动性、刀盘负荷、障碍物的处置、地层适应性等方面,对2种基本刀盘型式的特性进行了比较和分析。     

Experimental investigation of nozzle cavitating flow characteristics for diesel and biodiesel fuels

This study was performed to clarify criteria for cavitation inception and the relationship between flow conditions and cavitation flow patterns of diesel and biodiesel fuels. The goal was to analyze the effects of injection conditions and fuel properties on cavitating flow and disintegration phenomena of flow after fuel injection. To accomplish this goal, it was utilized a test nozzle with a cylindrical cross-sectional orifice and a flow visualization system composed of a fuel supply system and an image acquisition system. In order to analyze the rate of flow and injection pressure of the fuel, a flow rate meter and pressure gauge were installed at the entrance of the nozzle. A long distance microscope device equipped with a digital camera and a high resolution ICCD camera were used to acquire flow images of diesel and biodiesel, respectively. The effects of nozzle geometry on the cavitating flow were also investigated. Lastly, a detailed comparison of the nozzle cavitation characteristics of both fuel types was conducted under a variety of fuel injection parameters. The results of this analysis revealed that nozzle cavitation flow could be divided into four regimes: turbulent flow, beginning of cavitation, growth of cavitation, and hydraulic flip. The velocity coefficient of diesel fuel was greatly altered following an increase in flow rate, although for biodiesel, the variation of the velocity coefficient relative to the rate of flow was mostly constant. The cavitation number decreased gradually with an increase in the Reynolds number and Weber number, and the discharge coefficient was nearly equal to one, regardless of cavitation number. Lastly, it could not observe cavitation growth in the tapered nozzle despite an increase in fuel injection pressure.