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811.
桥梁桩基设计中若干问题的探讨 总被引:3,自引:0,他引:3
该文结合设计实践,参考相关规范及文献,针对现行公路桥梁地基与基础设计规范中关于桩基承载力设计计算的几个问题进行了初步探讨。 相似文献
812.
针对目前市场上所使用的后装压缩式垃圾车存在的结构缺陷,介绍了一种结构简单、易操控、改装成本低、整车轴荷分配合理、使用经济性好的新型后装压缩式垃圾车,并对该车的结构和工作原理进行了阐述。 相似文献
813.
席雷 《现代城市轨道交通》2012,(6):54-56
感应板是直线电机线路中的重要设备,文章对感应板高度调整工作的特点进行了介绍,并进一步分析了感应板高度变化的原因,在此基础上提出了感应板高度调整工作的若干建议。 相似文献
814.
815.
激光焊接技术在舰船建造中的应用 总被引:8,自引:3,他引:5
介绍了激光焊接技术的发展历史、工业焊接用激光源的基本特点、激光焊接技术用于造船业的优势及其存在的困难,重点介绍了激光焊接技术在舰船建造中的应用实例,包括激光焊接大型船板、激光焊接型材、焊接瓦棱夹层板、激光焊接修复等,指出了在舰船建造中开展激光焊接技术研究的必要性。 相似文献
816.
Friction and wear behavior between armor wire layers of umbilical plays an important role in its mechanical properties, in particular its fatigue life. The present paper addresses friction tests to investigate the interlayer sliding friction and wear mechanism of armor wires in an umbilical. A series of friction tests were carried out to study the evolution of coefficient of friction (COF) and wear between armor wire layers. The results show that the COF increases with increasing number of reciprocating sliding cycles in dry friction condition. A dual stable trend was found in the evolution process of interlayer friction and wear of armor wires. A friction model was proposed to describe this trend by dividing the evolution process into three stages: the initial stable stage, the transition stage, and the latter stable stage. The mechanism of the dual stable trend was revealed, which was mainly caused by wear process of nylon fiber tape, and effected by dry/wet wear condition and wear coefficient. The effect of the contact condition, sliding amplitude and number of nylon fiber tape on COF was studied. The COF of the latter stable stage increases with increasing sliding amplitude and number of layers of nylon fiber tape. The finding in this paper provides a valuable approach for a more accurate fatigue life prediction of an umbilical. 相似文献
817.
年票制是提高公路通行效率的行之有效的办法,但由于年票征管部门监管不力,导致车辆恶意逃费所致的通行费流失严重,针对我国城市年票监管实际情况,提出一种基于车牌识别的城市年票自动管理系统.首先介绍了该系统的架构以及年票收费站管理和委托站次票监管两个子系统的工作原理,接着重点论述实现该系统的三项关键技术:车牌识别技术、数据同步技术、IC卡防伪技术.该系统已在广东省中山市投入使用,运行稳定可靠,受到客户的好评. 相似文献
818.
This paper is concerned with the hydroelastic problem of a pontoon-type, very large floating structure (VLFS) edged with the perforated plates, non-perforated plates or their combination anti-motion device both numerically and experimentally. A direct time domain modal expansion method, taking amount of the time domain Kelvin sources in hydrodynamic forces, in which the fluid flows across the perforated anti-motion plate by applying the Darcy's law, is applied to the fluid–structure interaction problem. A quarter of numerical model is built based on the symmetry of flow field and structure in hydrodynamic forces, and special care is paid to the rapid and accurate evaluation of time domain free-surface Green functions and its spatial derivatives in finite water depth by using interpolation–tabulation method. Using the developed numerical tools and the model tests conducted in a wave basin, the response-reduction efficiency of the perforated plates is systematically assessed for various wave and anti-motion plate parameters, such as plate width, porosity and submergence depth. As a result of the parametric study, the porosity 0.11 is selected as the optimal porosity, and the relationship between the porosity and the porous parameter is developed by using the least-squares fitting scheme. After simulation and verification, the dual anti-motion plates which are the perforated-impermeable-plate combination attached to the fore-end and back-end of the VLFS, are designed for more wave energy dissipation and added damping. Considering variation of the water depths in offshore, discussion on the effectiveness of these anti-motion devices at different water depths is highlighted. 相似文献
819.
820.