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1.
重力式码头工程的预制构件一般重量较大,在批量大、规格多的情况下,选择何种搬运工艺,涉及场地布置、设备选用、施工操作人员的劳动强度、搬运效率和经济合理等一系列问题.采用2台轨道电动平车组合搬运3000~5000kN方块的工艺,为重力式码头的构件搬运开辟了新的途径,在港口水工建筑施工中具有广阔的应用前景.  相似文献   

2.
随着现代科学信息技术迅猛发展和广泛应用,我国测绘业已基本实现由传统模拟测绘技术体系向数字化、信息化测绘技术体系的跨越.地理信息是一种以采集、贮存、管理、分析和描述整个或部分地球表面空间地理分布有关数据的空间信息,已广泛应用于交通、电力、水利、农林、国土资源、环境保护、金融、电信、地质、矿产、城市建设、教育、人口、海洋以及军事等几十个领域.  相似文献   

3.
《机电设备》2007,24(3):I0007-I0007
法国船级社(BV)收购德国劳氏船级社(GL)已落下帷幕,收购失败.BV首席执行官曾强调,GL如果与BV合并,两大船级社将在世界各大船级社等机构中占据领先地位,这一地位在亚洲显得至关重要,大量投资将流向亚洲尤其是中国,以满足快速发展的船舶业市场.但是,GL汉堡总部对提高地位这一说法并不信服,因为自1994以来,GL已经在中国取得了稳固的市场地位,现在中国有50多家船厂已经拿到了超过350艘集装箱船、多功能船、散货船、油轮和化学品船的订单,而客户们信赖GL的质量保证、快速批准计划和可靠的技术支持.  相似文献   

4.
2008年4月3日上午。南通中远川崎船舶舾装码头彩旗飘扬,人头攒动,锣鼓喧天。全国政协副主席李金华、政协常委高俊良,交通运输部副部长徐祖远,江苏省副省长张卫国,中远集团总裁魏家福、党组书记张富生等集团领导,日本川崎重工株式会社副社长寺崎正俊以及南通市有关领导.日本川崎重工、中远造船工业公司和业界代表一百余人共同见证了中国首制1万标箱集装箱船——中远大洋洲轮命名交付仪式。  相似文献   

5.
耀思 《中国水运》2008,(4):12-14
党的十七大文件中第一次提到国家软实力问题。完成中华民族的伟大复兴,在于综合国力的全面提升,而综合国力既包括由经济、科技、军事实力等表现出来的“硬实力”,也包括以文化、意识形态吸引力体现出来的“软实力”。行业软实力是指一个行业以其自身的地位、作用和形象对社会产生的影响力、对公众产生的吸引力和对其他行业产生的仿效力。概括地讲,行业“软实力”包括三个要素,即理念先导力、精神感召力和舆论引导力,其中理念是先导,精神是动力,舆论是环境。  相似文献   

6.
公元前200多年,中国历史上演了有名的一幕:楚汉之争. 当时的情况是楚强汉弱,汉王刘邦连连吃败仗.可是刘邦是块牛皮糖、是个不倒翁,败了就逃,逃了又兜个圈子转回来,再打.楚王项羽受不了,对刘邦说:"不如我们一对一单挑,决个雌雄罢,免得天下百姓再为你我二人白白受苦了!"(愿与王独身挑战,以决雌雄,毋徒令天下父子为也.)刘邦笑了笑,答道:"吾宁斗智,不愿斗力."结果,力能拔山、气可盖世的楚霸王项羽,就这样慢慢被刘邦"耗"死了--流氓出身的刘邦成了汉高祖.  相似文献   

7.
The progress of economic globalization,the rapid growth of international trade,and the maritime transportation has played an increasingly significant role in the international supply chain.As a result,worldwide seaports have suffered from a central problem,which appears in the form of massive amounts of fuel consumed and exhaust gas fumes emitted from the ships while berthed.Many ports have taken the necessary precautions to overcome this problem,while others still suffer due to the presence of technical and financial constraints.In this paper,the barriers,interconnection standards,rules,regulations,power sources,and economic and environmental analysis related to ships,shore-side power were studied in efforts to find a solution to overcome his problem.As a case study,this paper investigates the practicability,costs and benefits of switching from onboard ship auxiliary engines to shore-side power connection for high-speed crafts called Alkahera while berthed at the port of Safaga,Egypt.The results provide the national electricity grid concept as the best economical selection with 49.03 percent of annual cost saving.Moreover,environmentally,it could achieve an annual reduction in exhaust gas emissions of CO2,CO,NOx,P.M,and SO2by 276,2.32,18.87,0.825 and 3.84 tons,respectively.  相似文献   

8.
As a novel type of foundation in beach and shallow sea,the bucket structure is especially suitable for complex conditionssuch as soft clay ground and the worse types of sea environments.In this paper, the bearing capacity of a multi-bucket structure isstudied by experiments with a single bucket and four-bucketfoundation in a saturated sand layer. Based on the experimentaldata and numerical analysis results, the bearing capacity behaviorand the bucket group effect are compared and analyzed.Furthermore, some influential factors, such as the soil type, theratio of length to diameter L/D, the ratio of the bucket spacing tothe bucket diameter S/D, and the bucket number are introduced andtheir effects on the multi-bucket structural capacity are investigatedThe vertical static capacity adjustment factor is introduced toevaluate the bucket group effects of the multi-bucket foundation.  相似文献   

9.
京杭运河是我131南北向水上运输尤其是煤炭运输的大动脉,同时也承担了南水北调输水主干线的重任,具有极其重要的战略地位.微山船闸作为京杭运河Ⅱ级坝上唯一的通航枢纽,承担着京杭运河过Ⅱ级坝的所有货物运输量.为促进区域经济发展,保持京杭运河航运的畅通,充分发挥京杭运河国家水运主通道的作用,彻底消除安全隐患,从工程、环境、经济等角度探讨微山船闸的改扩建模式.  相似文献   

10.
有限水深中垂直下潜弹性薄板的水波散射(英文)   总被引:1,自引:0,他引:1  
The problem of water wave scattering by a thin vertical elastic plate submerged in uniform finite depth water is investigated here.The boundary condition on the elastic plate is derived from the Bernoulli-Euler equation of motion satisfied by the plate.Using the Green’s function technique,from this boundary condition,the normal velocity of the plate is expressed in terms of the difference between the velocity potentials(unknown)across the plate.The two ends of the plate are either clamped or free.The reflection and transmission coefficients are obtained in terms of the integrals’involving combinations of the unknown velocity potential on the two sides of the plate,which satisfy three simultaneous integral equations and are solved numerically.These coefficients are computed numerically for various values of different parameters and depicted graphically against the wave number in a number of figures.  相似文献   

11.
郁天磊 《船舶工程》2018,40(7):20-24
根据第一代40万吨超大型矿砂船(VLOC)的状况勘验情况,对船舶的典型布置和结构特点进行概括,并对船舶的典型结构缺陷进行总结。基于结构特点和运营中的结构受力情况,对典型结构缺陷进行分析。基于分析结果,对典型结构缺陷的处理措施进行介绍。根据现有结构状态,提出结构检验注意要点,为第一代40万吨VLOC的后续结构检验提供指导,也为即将投入运营的第二代40万吨VLOC的结构检验提供参考,以有针对性地对40万吨VLOC进行结构检验,提高结构检验效率。  相似文献   

12.
海上极端波过去常常导致船舶结构的极限破坏,而船舶的极限崩溃涉及到船体结构的动态极限强度和结构非线性.该文通过二维的水弹塑性方法研究了集装箱船在极端波中的非线性动态强度,该方法考虑了船体的极限强度以及船体结构的非线性和波浪之间的耦合.并通过该二维水弹塑性方法和极限评估方法研究了船体结构的结构优化.文中还通过二次规划法(SQP)来优化基于非线性的动态强度的集装箱船体结构.最少的结构成本是本优化的目标函数,约束条件保证船体的强度要小于结构的极限强度,并且结构设计尺寸要满足规范的要求.随着设计波高的变化,这些优化的设计变量的变化趋势得以发现,一些研究的结论可用于船舶规范的参考.  相似文献   

13.
船舶结构高阶动力分析的模型简化方法研究   总被引:1,自引:0,他引:1  
庞福振  姚熊亮  朱理 《船舶力学》2010,14(11):1263-1275
针对船舶结构动力分析的模型简化条件及方法进行研究,通过讨论阻尼对结构动力响应分布的影响,从波动角度研究了以局部结构代替整体模型进行动力分析的模型简化条件,提出了船舶结构高阶动力分析模型简化的行波法.研究表明,阻尼可降低结构的动力响应,并使结构动力响应随距激扰力作用点的距离呈指数函数衰减;结构动力模型能否简化很大程度上取决于阻尼、激扰频率及结构物理参数等条件,激扰力在简化模型与原结构中产生的弯曲波传播距离相差整数倍波长时,简化模型的动力响应可最大限度地与原结构保证一致,进而提出了均质结构及板架等复杂结构动力分析的模型简化定量方法一行波法;并采用算例验证了其有效性.  相似文献   

14.
Undoubtedly, the main advantage of the additive manufacture technology is to allow building miniature structural parts with a large degree of complexity such as to replicate structural details of real-scale marine structures. This work presents a new technique for reproducing the structural response of large-scale thin-walled metallic structures when subjected to crushing loadings by using scaled-down additive manufactured models. This technique couples scaling laws for strain rate sensitive materials and a thickness distortion technique based on the structural collapse mode. In order to validate this coupled technique, the structural response of a large-scale crushing test of a web girder structure was experimentally replicated by using a 1/40 scale reduction model. The results and conclusions summarize the prospects and limitations of additive manufacturing of miniature complex marine structures for structural purposes and crashworthiness verification.  相似文献   

15.
张健  尹群  王珂  孙彦杰 《船舶工程》2007,29(1):20-23
以吸能原理为理论依据,提出船舶双层底的四种新型抗爆结构形式,建立传统形式和四种新型结构形式的有限元模型.利用MSC.Dytran软件进行数值仿真,获得在相同水下爆炸载荷下五种结构形式的吸能性能、内底板最大变形量、典型部位加速度,并分析比较了五种结构的抗爆性能,从中获得较优的结构形式.  相似文献   

16.
选取24 000 TEU集装箱船上层建筑作为研究对象,进行有限元建模,对其整体吊装过程进行模拟。对初始吊装方案和加强方案进行校核,查看结构应力和结构变形情况,并根据结果反馈对初始吊装方案和加强方案进行相应调整。优化模型显示结构突变成功消除。对吊点附近的结构进行加强,确保结构应力顺利传递,应力降至许用范围内,上层建筑安全吊装。  相似文献   

17.
B. Rapo 《Marine Structures》1988,1(3):189-217
The structural analysis based on application of numerical methods used in the solution of complex structural problems, when applied correctly, is a powerful tool leading to rational structural design of ships. This paper discusses the practicalities of its application and indicates that in order to achieve the stated objective, the following are essential pre-requisites: a) full understanding of the problem; b) ability to solve the problem using currently available methods; and c) ability to interpret the results of the analysis correctly. Whilst there is still a lot of discussion on whether the structural analysis represents a structural design or a structural verification tool, the view expressed in this paper is that the structural analysis should mainly be used in the latter context. This means that a sound engineering solution ought to be established in the first phase of the analysis and used as a basis. The final results will then only be used to perfect the structural detail and modify the areas where rapid stress gradients occur. Any other approach would invariably require repetitive, time consuming and costly iterations which under normal circumstances may prove to be counter-productive. This paper presents a few examples of practical application, the methodology of achieving the solution and the way of interpreting the results.  相似文献   

18.
A common approach to investigate the response of a structural detail such as a hatch corner is to compute the seakeeping loads using a linear 3D Boundary Element Method (BEM) and transfer the seakeeping loads to a Finite Element (FE) model of the ship structure. This approach is suitable for computations of the fatigue loading of structural details near amidships because a majority of the fatigue loading will occur in mild sea-states where the loading may be assumed linear. However, the linear seakeeping model may not hold when one investigates the ultimate response of the local bow structure of a ship which is designed to remain operational in severe conditions, for example, a frigate. A linear seakeeping analysis will significantly underpredict the loading at the bow because both the impulsive slamming loads and the non-linearities in the non-impulsive wave loads will contribute significant to the structural loading.The non-linear loads require one to first derive a short-term distribution of the local structural response before the ultimate value of the response can be derived. A method to compute the short-term distribution of a structural detail is presented in this paper. The first step is to perform seakeeping analyses which includes slamming, non-linear Froude-Kryloff and hydrostatic loads. The short-term distribution of the total hydrodynamic loading at the structural detail is obtained by simulating the seakeeping response for several hours. The response of the local structure is computed for the most severe impacts found in the seakeeping simulation. The hydrodynamic loading, including the non-linear contributions, is transfer to the structural model and the structural response is computed using the FE-method. The results of the structural analyses allow one to transform the short-term distribution of the structural loading to a short-term distribution of the response of the structural detail. A designer can obtain the ultimate structural response by entering the probability at which one accepts overloading of the structure in the short-term distribution of the response of the structural detail.  相似文献   

19.
基于Autodesk平台的BIM技术在水运工程结构设计中缺少一款与建模软件Revit匹配的结构计算软件,为此提出一种将通用有限元结构计算软件ANSYS与Revit耦合的方法。由于Revit仅在族环境中才能建成水运工程参数模型,所以先对Revit基础图元类型进行编程分类,把可载入族赋予结构属性。采用Revit API技术过滤结构模型的几何信息、属性信息、材质信息,再将提取信息编译成ANSYS命令流文件,实现结构计算软件ANSYS与BIM建模软件的数据转换,并依据Revit布尔算法优化ANSYS结构计算前处理的映射网格划分步骤。最后使用某船闸主体工程进行验证,证明本方法在结构计算中运用是可行性的。  相似文献   

20.
船体结构耐撞性优化设计的主要目的是在船舶碰撞研究的基础上对结构进行优化设计,提高船体结构的耐撞性能。基于正交试验设计、BP神经网络和遗传算法,形成了船体结构耐撞性能优化设计方法。提出了一种耐撞性综合指标,并以此指标作为优化的目标函数,以结构质量为约束条件,利用MSC/Dytran有限元软件对船舶碰撞进行数值仿真,完成对某船舷侧结构进行耐撞性优化设计,结果表明优化过后结构耐撞性能有较大提高,这为结构耐撞性能优化设计提供了一种新的思路和方法。  相似文献   

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