Azimuthal wave number control of oscillatory thermocapillary convection in a liquid bridge

Thermocapillary convection in a half‐zone liquid bridge of high Prandtl number fluid is widely known to exhibit a three‐dimensional oscillatory flow after the onset of oscillation. The oscillatory flow presents ‘standing’ and ‘traveling’ flows depending upon the temperature difference between the top and bottom rods. In the oscillatory state, the flow shows a modal structure with an azimuthal wave number that depends on the aspect ratio of the liquid bridge and the intensity of the thermocapillarity expressed by the Marangoni number. The present study attempted to control the azimuthal wave number by heating the free surface locally with a prescribed frequency and intensity. The flow in the liquid bridge exhibited different modal structures depending on the heating conditions and a relationship between the frequency and the modal structure was obtained. © 2005 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(7): 460–469, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20086     

浅谈公路工程项目的索赔

介绍了公路工程项目中常遇到的索赔的定义、原则和程序，并明确了可索赔的条款，深入探讨了索赔成功的关键技巧，以期应用在投标前后及整个施工过程中，获取较为理想的经济效益。     

Optimization of management strategies applied to the national reinforced concrete bridge stock in France

The increasing age of national highway bridge stocks demands novel management policies that can maintain or increase safety levels in the light of reducing and budgets from the government. The French Highways Agency uses its Image Qualité Ouvrages d'Art – Structural Quality Imaging (IQOA) inspection programme to determine the conditions of its bridges. The present paper principally describes the development of a model to predict different trends in bridge condition rating in the light of different management strategies. Whilst the approach described is intended to be a general method for managing bridges, it will be demonstrated by particular reference to the stock of reinforced concrete bridges managed by the French Highways Agency. The prediction model utilises Markov chains, which were chosen because they allow a non-parametric discrete model to be built, to evaluate the varying condition of the whole bridge stock over time. The development of the model is described in detail, together with how the hypotheses for applying the Markov chains were validated to accurately predict the transition matrices between different IQOA states. The paper then goes on to describe how the model is used to differentiate between different management strategies, and to predict how future costs can be optimised to give the most efficient management actions across the whole bridge stock under different constraints.     

钢便桥及钻桩平台施工方案研究

结合某道路改造工程实例,从钢便桥、钻桩平台的使用功能,总体设计,结构设计和施工工艺等方面进行了研究,提出了具体的施工方案,为今后钢便桥及钻桩平台的施工提供了参考借鉴。     

公路施工企业项目管理对策分析

针对公路施工企业项目管理过程中客观存在的问题,运用现代项目管理理论和方法,结合企业管理的实践,从多方面进行分析并提出一些有价值的对策,以达到预期的项目管理目标。     

公路旧路基状态检评的规范要求及启示

通过分析路基状态检评相关规范的要求,总结提出当前路基状态检评技术的关键问题,并提出了相应的研究和工作建议,以期为提高旧路基状态检评的科学性和规范性提供科学依据。     

对桥梁施工中若干预应力技术的研讨

结合济南二环东路高架桥四合同十四联现浇连续箱梁预应力施工经验,探讨了施工中伸长量计算与设计图纸中伸长量的区别,介绍了如何精确计算伸长量,阐述了张拉次数的控制方法,并分析了两端张拉与一端张拉的区别,以期指导实践。     

简述高速公路桥头跳车的因素和处理方法

简述桥头跳车的厚因及其对行车速度的影响，并从理论与施工两方面入手探讨了解决高速公路桥头跳车的方法，分别介绍了路基、台背、路面三个关键部应的处理方法．以期指导实践，避免桥头跳车问题的产生。     

桥头跳车产生的原因及防治措施

叙述了桥头跳车病害产生的原因,提出,应对桥头跳车应采取的防治措施,以便最大限度地减少和改善桥头跳车问题。     

高速公路上连续梁式渡槽的设计

针对合淮阜高速公路上的跨度较大的地面输水建筑物,普通的梁式简支渡槽难以满足要求的特点,采用了预应力连续梁式渡槽,简略介绍了该渡槽结构设计和结构静力计算方法,指出这是一种经济合理并满足耐久性的结构。