Uncertainty and joint probability of sea ice loads

Ｕｎｃｅｒｔａｉｎｔｙａｎｄｊｏｉｎｔｐｒｏｂａｂｉｌｉｔｙｏｆｓｅａｉｃｅｌｏａｄｓ￥ＬｉｕＤｅｆｕ；ＹａｎｇＹｏｎｇｃｈｕｎ；ＷａｎｇＣｈａｏａｎｄＬｉＴｏｎｇｋｕｉ（ＯｃｅａｎＵｎｉｖｅｒｓｉｔｙｏｆＱｉｎｇｄａｏ，Ｑｉｎｇｄａｏ２６６００３，...     

轻质硬壳海堤断面设计初探

从海堤本身角度看，坝体过重与填料松散是影响其稳定性的主要因素，因此轻质硬壳堤坝是一种很好的选择。该结构采用高强度材料作为外壳，以松散材料填充坝体。根据受力特性、构造要求、施工条件及抗滑稳定条件拟解决结构断面设计的一些基本问题，并结合实例通过对比计算分析，说明轻质硬壳海堤比传统海堤具有更高的整体稳定性。     

海水工厂化养鱼排污水处理的实验研究与工程设计

本文从保护海洋环境出发，论述研究设计海水工厂化养鱼排污水处理工程的重要性，提出用光合细菌（PSB）和海藻试验研究工厂化养鱼排污水处理的效率、特性及副产品的综合利用。通过工程计算，设计出工艺流程图及光合细菌反应池、二沉池和海藻塘的工程容量。     

Reinforcement of Soft Foundation with Geotextile and Observation for Sea Dike Project of Zhapu Port

1 .IntroductionTheZhapuPortissituatedonthenorthbankoftheHangzhouBay ,nearZhapuTowninPinghuCity ,Zhejiangprovince .Asthefirststepofconstruction ,reclamationwasaccomplishedinthehinter landoftheharbor.Theborderdikeofafulllengthof 1 2 71mislocatedinthetidalregionoftheHangzhouBay .ThepreliminarydesignofthisprojectwascompletedinJune 1 986 ,anditsconstructionbeganinJuly 1 986 ,andwascompletedinMarch 1 991 .TheseadikewasbuiltontheQ4marinedepositofsaturatedsoftclaywithathicknessofabout2 7mandgeo…     

Finite Element Method for Design of Reinforced Concrete Offshore Platforms

A design method of reinforced concrete (R. C.) offshore platforms with nonlinear finite element analysis is proposed. According to the method, a computer program is developed. In this program nonlinear constitutive relationships and strength criteria of concrete and steel bars are included, and the progressive cracking and crushing of the concrete are taken into account. Based on the stress distribution obtained by the nonlinear finite element analysis, the amount of reinforcement in the control sections can be computed and adjusted automatically by the program to satisfy the requirement of the design. The amount of reinforcement required in the control sections, which are obtained with the nonlinear finite element analysis, is agreeable to that obtained in the experiment. This shows that the design method of R. C. offshore platform with the nonlinear finite element method proposed by the authors is reliable for practical use.     

北部湾沿岸海区设计波浪的确定

本文基于北部湾沿岸海区多年的实测资料，于不同海区主浪向和次主浪向分别取年极值波高为样本资料．采用Ｐ－Ⅲ型和短期测波资料频率分析方法，分别估算了各海区不同重现期的设计波高，并依据式（１）计算出相应的平均周期。尽管样本资料和估算方法不变，但每次估算的结果互不相同，其差异甚至很大．利用Ｋｏｌｍｏｇｏｒｏｆｆ等适合度方法检验所得的结果，能够准确地判断出沿岸各海区不同重现期的最佳设计波浪。     

均匀设计在后棘藻培养基中的应用

将均匀设计的方法应用于一种海洋微藻：后棘藻（Ellipsoidion)培养基的优化。设计了硝氮、氨氮、磷酸盐三因素各五个浓度水平的试验，根据均匀设计表设计了10种培养基，检测细胞浓度、脂肪酸含量和产量。结果表明：在硝氮、氨氮浓度均为1．92mmol/L，磷酸盐浓度为0．082mmol/L，细胞浓度达到最大值167．23mg/L。在硝氮浓度为0．84mmol/L，氨氮浓度为3．38mmol/L，磷酸盐浓度为0．07mmol/L时，EPA含量达到最大值7．748％。在硝氮浓度为0．915mmol/L，氨氮浓度为1．92mmol/L，磷酸盐浓度为0．072mmol/L时，EPA产量达到最大值9．999mg/L。     

桶形基础及其作用下的粉质土海床失稳机制研究的试验设计

在阅读、分析以往的有关资料的基础上 ,结合实际的试验条件 ,对桶形基础及其作用下的粉质土海床失稳机制研究的试验作出了专门设计。该设计通过配土、设计模型桶基和负压沉贯的操作过程、设置孔压传感器等实验手段 ,努力从土体破坏的角度 ,寻求负压沉贯过程中沉贯负压、沉贯阻力及孔隙水压力之间的变化关系和确定桶基的上拔力。并且指出了数据处理的基本思路 ,以利于课题的深入研究。     

Multilevel Optimal Design of Prestressed Lightweight Concrete-Steel Platform Structures

The concrete-steel platform structure is rather complicated because it involves such materials as concrete, reinforcing bars, steel, and so on. K the traditional dimension optimization method is employed, the optimal design of the platform will meet many handicaps, even it cannot be implemented at all. The multilevel optimal design approach is an efficient tool for the solution of large-scale engineering structures. In this paper, this approach is applied to the optimal design of a concrete-steel platform, which is formulated as a system level optimal design problem and a set of uncoupled substructure level optimal design problems. The process of optimization is a process of iteration between system level and substructure level until the objective function converges. An illustrative example indicates that this method is effective in the optimal design of concrete-steel platforms.     

Estimation of extreme floods of the River Meuse using a stochastic weather generator and a rainfall–runoff model / Estimation des crues extrêmes de la Meuse à l'aide d'un générateur stochastique de variables météorologiques et d'un modèle pluie–débit

Abstract

A stochastic weather generator has been developed to simulate long daily sequences of areal rainfall and station temperature for the Belgian and French sub-basins of the River Meuse. The weather generator is based on the principle of nearest-neighbour resampling. In this method rainfall and temperature data are sampled simultaneously from multiple historical records with replacement such that the temporal and spatial correlations are well preserved. Particular emphasis is given to the use of a small number of long station records in the resampling algorithm. The distribution of the 10-day winter maxima of basin-average rainfall is quite well reproduced. The generated sequences were used as input for hydrological simulations with the semi-distributed HBV rainfall–runoff model. Though this model is capable of reproducing the flood peaks of December 1993 and January 1995, it tends to underestimate the less extreme daily peak discharges. This underestimation does not show up in the 10-day average discharges. The hydrological simulations with the generated daily rainfall and temperature data reproduce the distribution of the winter maxima of the 10-day average discharges well. Resampling based on long station records leads to lower rainfall and discharge extremes than resampling from the data over a shorter period for which areal rainfall was available.