大型油船和集装船静水弯矩的统计特性研究

本文介绍了国内外静水弯矩的研究现状，对Ｓｏａｒｅｓ和Ｍｏａｎ的回经验回归公式进行了详细讨论，发现不同的研究人员对静水弯矩统计特征的认识存相当大的差异。文中对静水弯矩均值和变异系数对船舶总纵强度安全指数的敏感度进行了分析，发现均值比变异系数更加重要。在分析和比较的基础上，根据简单可靠的原则，对集装箱船和油船的静水弯矩统计特征计算提出了如下建议，集装箱船，Ｍ２／Ｍ＝０．７０，Ｃｏｖ＝０．３０，油船，     

顶级巴拿马型集装箱船总强度的前期研究

该文根据顶级巴拿马型集装箱船的特征,针对4600TEU巴拿马型集装箱船中剖面构件的设计结果,讨论了压载到港时不同配载状况对静水弯矩的影响,分析了船体的纵向弯曲强度和总强度。     

大型集装箱船极限强度准则可靠性研究

本文对某一万箱级和某两万箱级的2型超大型集装箱船的极限承载能力分布、静水弯矩分布、波浪弯矩极值预报以及UR S11A要求的极限强度进行了分析，采用改进的一次二阶矩法（FORM），对2型船的失效概率进行计算，旨在验证满足UR S11A极限强度要求的超大型集装箱船的安全水平，以验证此强度准则的可靠性。     

船体梁静水载荷效应统计预报

船体梁静水剪力、弯矩等是由装载状态决定的载荷效应。营运船舶装载记录表明，实际装载状态具有不确定性，由此导致载荷效应发生变异，其统计特性可利用回归公式或随机模拟原理进行估算或预报。通过对油船、散货船、滚装船及集装箱船约2000种随机工况所作的统计分析，表明其静水弯矩等随装载偏差的变化近似于正态分布律，并具有比船体中剖面模数或钢材屈服极限更为显著的变异性。在船舶结构可靠性分析或理性设计中，合理估算并预报这种及异性是必要的。     

超大型油船破损剩余强度可靠性分析

根据MARPOL公约,对CSR-H规定的破口范围进行概率分析。以一艘超大型油船为例,分别统计了单舱破损后各个肋位的静水弯矩概率特征和基于全球海况谱的一周波浪弯矩预报值;基于Smith法的船体梁极限弯矩计算软件,分别统计了各舱破损后极限弯矩的概率特征;采用改进一次二阶矩法,计算了各舱破损后的剩余强度可靠度。研究结果表明：机舱和首尾货舱发生破损后整船失效概率较低,中部货舱区域发生破损后整船失效概率较大,尤其在静水中垂破损工况下最危险,失效概率在10^-2量级。     

基于静水阻力与参数横摇的集装箱船线型优化研究

对一条8000TEU集装箱船进行线型优化时不仅考虑了静水阻力性能,还将参数横摇指标用于判断集装箱船线型的优劣。在获得8000TEU集装箱船两个优化方案的静水阻力后,采用非线性时域面元法对两个方案的参数横摇进行了系统分析。分析结果表明,在相近静水阻力性能和同样的海况中,A1方案的最大参数横摇幅值明显小于A0方案。论文研究为集装箱船性能的优化增加一项目标,为集装箱船线型优化设计提供了新的思路。     

协调版共同结构规范对港口工况下散货船的影响分析

协调版共同结构规范（CSR-H）对港口工况下船体梁强度和船体构件局部强度的要求与先前的油船共同结构规范（CSR-OT）基本一致,而相比散货船共同结构规范（CSR-BC）有明显变化。通过对比分析CSR-H和CSR-BC对于港口工况具体要求的差异,并结合实船数据分析,阐述基于CSR-H要求的港口工况对散货船结构设计的影响;并探讨针对符合CSR-H的散货船,如何合理选取船体梁许用静水弯矩值和许用静水剪力值。     

3800箱集装箱船总纵强度计算两种方法对比研究

本文对3800箱集装箱船进行了整船有限元分析,计算了在设计静水弯矩、波浪弯矩、水平弯矩和扭矩作用下的船体总纵强度,并与基于薄壁梁扭转理论的总纵强度计算结果进行了比较,对两种方法的应用前景作出评论。     

超大型集装箱船结构设计关键技术分析

针对超大型集装箱船结构布置进行多方案设计对比分析.以某万箱船为例,对比了8种不同结构布置方案,确定了货舱区结构设计、横舱壁支撑系统、设计静水弯矩、纵骨型材选择以及货舱内装载高箱对结构性能的影响.该研究对超大型集装箱船结构优化设计有一定的参考意义.     

船舶结构极限波浪弯矩统计特征的一致性定义

在船舶结构界可靠性方法已得到越来越广泛的应用。在进行现有船舶的可靠性分析或对新船制订可靠性设计规范时，必须要首先确定能力与载荷的统计特征。对于船舶结构来说，波浪弯矩是主要的载荷，极限波浪弯矩的统计特征对极限强度的可靠性分析十分重要。但是，通过研究发现，不同的文献中给出的用于确定极限波浪弯矩统计特征的概念和方法并不一致，这一差别可能对了随后的船舶结构可靠性分析和设计有一定的影响。本文旨在对船舶结构极限波浪弯矩统计特征的一致性定义作一些讨论，以期澄清一些概念。     

Probabilistic modelling of time-varying still-water load effects in tankers

Analysis of recorded still-water load effects in tankers and of the design conditions in the load manual show that these are situations in which the still-water load effects change significantly during voyages, in particular, for double-hull tankers. The still-water load at a random point during a voyage was simulated by assuming a normal distribution of departure and of arrival data as well as a linear variation of intensity between departure and arrival for each pair of sampled values. It was observed that, in most cases the simulated data followed a normal distribution and this has been proposed as a model. The mean and standard derivation of this distribution should be the average of the respective values at departure and arrival.     

基于HCSR与CSR—OT的油船屈服强度直接计算评估对比分析

针对屈服强度直接计算的载荷、计算工况、建模原则、边界条件及屈服强度衡准,对比HCSR和CSR—OT,分别应用这两规范对多条油船样船进行屈服强度直接计算,提出一种可行的数据对比方法对油船典型构件的计算结果进行统计分析,给出关于HCSR屈服强度直接计算的具体处理方法。     

波激振动和砰击颤振对大型油船疲劳强度影响研究

文章给出线性波激振动和砰击颤振引起的大型油船结构疲劳贡献度的计算方法。基于三维线性水弹性理论可计算得到包括刚体和2节点的振动模态下的垂向弯矩的传递函数,采用谱分析法对某30万吨油船进行结构疲劳强度计算,分析波激振动对船体结构疲劳损伤影响;基于二维非线性波浪载荷程序（含砰击颤振的波浪载荷）,采用时域方法对该油船进行船体梁弯矩计算,分析砰击颤振对船体梁弯矩及疲劳载荷的影响;结果表明对于该类大型油船波激振动和砰击颤振对船体的结构疲劳损伤的影响不可忽略。     

绿色油船发展趋势分析

以油船防污染为切入点,深入探讨单壳油船到双壳油船,再到共同规范时代油船的产生、发展变化,对未来绿色船舶发展浪潮中油船发展趋势进行分析,并针对业界应对绿色油船发展提出建议。     

Fatigue damage calculation for oil tanker and container ship structures

The fatigue behaviour of longitudinal stiffeners of oil tankers and container ships, subjected to dynamic loads, is analysed. The following dynamic load components are considered: hull girder vertical wave bending moment, alone and combined with the horizontal wave bending moment, hydrodynamic pressure and inertial forces caused by cargo acceleration.

The spectral method was selected to calculate the fatigue damage, based on S—N curves and Miner's rule. Following this approach, the fatigue damage may be calculated as a function of a stress parameter Ω_p, which represents the cumulative effect of wave induced loads in the unit of time and incorporates the combined effects of stress level and its occurring frequency.

Simple formulas for Ω_p of oil tankers and container ships are given, obtained from the results of hydrodynamic analyses performed on several ships, in different wave environments.

Several examples show the applicability of the methods to real ship structures. The method, however, still needs to be calibrated because of the simplifying hypotheses introduced in the loading conditions.     

Hull-girder reliability of new generation oil tankers

A series of new generation oil tankers is presently under construction. These ships differ from traditional oil tankers by their unusual form and therefore direct hydrodynamic analysis is used to determine design vertical wave bending moments instead of adopting IACS rule values. The purpose of the paper is to quantify changes in hull-girder reliability resulting from the new design features. To achieve this, first-order reliability analysis is carried out with respect to ultimate collapse bending moment of the midship cross section of a new generation oil tanker and of a conventional “rule” designed oil tanker. The stochastic model of wave-induced bending moment is derived from direct hydrodynamic analysis performed according to IACS Recommendation No. 34 Standard Wave Data, Rev 1, 2000. The probability distribution of the still water bending moment is assumed based on the data from loading manuals. The model uncertainties of linear wave loads, non-linearity of the response as well as load combination factors are included in the reliability formulation. The reliability analysis is performed for three relevant loading conditions: full load, ballast and partial load and for two states of the hull: the “as-built” hull and “corroded” hull according to anticipated 20-year corrosion. One of the most interesting conclusions from the study is that the annual hull-girder reliability of new generation oil tanker is increased considerably compared to the conventional oil tanker. Sensitivity and parametric studies are performed with respect to random variables representing modelling uncertainties. The results of a sensitivity study enable sorting of pertinent variables according to their relative importance, while parametric study is used to quantify changes in the reliability indices for moderate variation of input parameters. Furthermore, some other results and discussions are presented pointing out the benefits of introducing the ship reliability methods in design practice, especially if this refers to new designs.     

油船主尺度确定

1973年国际防止船舶造成污染公约的1978年议定书规定,载重量二万吨以上的原油船和载重量三万吨以上的成品油船都要设置专用压载水舱,并对货油区范围内的专用压载水舱和非油处所要求满足保护面积指标。作者就贯彻这一新规定,对载重量三万至十万吨级原油船主尺度有关问题作了研究。本文简要分析了新规定引起油船主尺度、结构重量与容量、货舱结构划分形式等方面的变化,引述了作者建立的有关确定主尺度的主要数学模型,并给出了以多目标分层序列最优化方法确定油船主尺度的方法和过程。文后附按此方法对六万五千吨载重量原油船主尺度确定的计算结果。     

油运费率指数的规律性分析及短期预测

以时间序列统计分析作为基础研究手段,分析了不同类别油运费率指数的运行规律,并应用ARIMA时间序列模型对160000dwt以上的原油运费率指数进行了短期预测,取得了较好的预测效果。     

镇海算山码头#7泊位改造工程的论证复核

介绍镇海算山码头#7泊位5万吨级成品油码头兼靠10万吨级油轮的改造设计。对泊位长度、靠泊设施间距、泊位作业标准和平面水域等进行全面论证,对码头水工建筑物的设计荷载、结构内力进行复核计算。本着投资少、工期短、施工简单和对生产影响小的原则,提出对码头上的登船梯、系船设施等进行必要的改造,以满足兼靠10万吨级油轮的需要。