先进电力电子技术在超高压输电网中的应用

简要介绍了先进电力电子技术在输配电中的应用,主要包括高压直流输电、柔性交流输电和定制电力技术三个方面.在叙述电力电子技术的发展和应用情况的基础上,重点阐述了由中国电力科学研究院自主集成的可控串补和静止无功补偿器成套设备的关键技术,强调了自主开发的重要性.     

人工挖孔灌注桩设计与施工

在丘陵多溶洞地区,挖孔桩可有效地避免塌孔以及漏浆现象。以沪蓉西高速公路上的一座特大桥为例,介绍挖孔桩的适用范围及其优点,对桩身和护壁的强度进行分析与计算。     

关于货车转向架的发展探讨

分析了国内外货车转向架的发展现状 ,根据国外转向架发展趋势 ,得出研制大轴重、高速货车转向架应遵循的原则。提出了我国未来货车转向架研制新的要求。最后介绍了 2 5t轴重货车转向架的研制情况。     

浅谈高速动车组的制动方式及特点

综合叙述高速动车组的几种制动方式及其特点 ,并根据国外高速铁路所采用的不同制动方式 ,结合我国高速铁路设计的实际情况 ,分别在动力分散及动力集中两种牵引模式下所采用的制动方式的异同及优缺点进行分析比较 ,为今后的高速铁路设计做技术准备。     

软土地基预制预应力混凝土管桩施工

结合工程实例,从预制预应力管桩的进场质量验收开始,介绍了预制管桩在液压沉桩施工过程中的质量控制方法及注意事项。预制管桩采用液压沉桩施工,无噪声污染,减少施工扰民,值得在城市建筑的基础施工中推广。     

水泥混凝土不同强度之间的关系

水泥混凝土强度的不足是水泥混凝土路面破坏的原因之一。在国内外学者研究的基础上，阐述了混凝土理论破坏机理，分析了强度的影响因素，试验得出适合浏阳地区强度之间的经验公式。     

Effect of pitting corrosion on local strength of hold frames of bulk carriers (2nd Report)—Lateral-distortional buckling and local face buckling

Pitting corrosion is typical corrosion observed on coated hold frames of bulk carriers which exclusively carry coal and iron ore. In order to secure the safety of these types of bulk carriers, it is important to understand the effect of pitting corrosion on local strength of hold frames.

In order to investigate this effect, a series of 4- and 3-point bend tests on structural models which consist of web, shell and face plates has been carried out. Artificial pitting was created on the web plate to simulate pitting. In the 4-point bend tests, two equal concentrated loads have been applied vertically at the one-third points of simply supported models so that compression load due to bending would act on the face plate. In this testing condition, lateral-distortional buckling occurred before reaching the ultimate strength and local buckling of the face plate was observed after reaching the ultimate strength. The effect of web plate pitting on the lateral-distortional buckling strength was found to be small but the ultimate strength decreases with increase in the degree of pitting intensity. In the 3-point bend tests, concentrated load has been applied vertically at the center of simply supported models so that compression load due to bending would act on the face plate. In this testing condition, local face buckling occurred just after reaching the ultimate strength. The ultimate strength is found to be decreasing with increase in the degree of pitting intensity.

A series of non-linear FE analyses has been performed to simulate the deformation behavior observed in the tests. It has been revealed that even in the case of randomly distributed pitting corrosion the ultimate strength of the structural models was almost the same as that of the structural models with uniform corrosion corresponding to the average thickness loss.     

夹芯复合材料在潜艇声隐身结构中的应用及其相关技术研究

潜艇的声隐身问题一直是研究的热点，各种新的声学材料和结构不断涌现。首先对复合材料在潜艇声隐身结构中的应用情况进行了分析，对其材料、结构形式、作用效果等方面进行了详细阐述，提出了夹芯吸声复合材料作为水下声隐身结构的发展趋势。然后利用数值计算的方法，对夹芯复合材料的声学性能进行了分析，得到了夹芯复合材料各层材料参数，如厚度、声特性阻抗和损耗等对声学性能的影响规律。最后，评估了典型局部结构壳板应用夹芯复合材料后的力学性能和声隐身性能。结果表明，潜艇非耐压结构的壳板采用夹芯复合材料可以满足结构的力学要求，与钢结构相比声隐身能力得到提高。     

基于IACS共同规范的油船极限强度及敏感性分析

基于IACS共同规范研制了双壳油船总纵极限强度的计算程序,计算了一个箱形梁模型和两条油船的总纵极限强度,计算结果表明本文研制开发的计算程序是正确可靠的,可供油船船体结构设计参考和使用。本文还对影响船体梁极限强度的参数进行了敏感性的简要探讨,得出有用的结论。     

深水半潜式钻井平台波浪载荷预报与结构强度评估

采用理论分析和模型试验相结合的方法,对一深水半潜式钻井平台进行了波浪载荷预报和结构强度评估,进而为平台结构设计提供了参考依据.同时,对半潜式平台波浪载荷预报和结构强度评估的分析方法和流程进行了归纳与总结.