A Probability Distribution of Surface Elevation for Wind Waves in Terms of the Gram-Charlier Series     

HUANG  Chuan-jiang 《中国海洋工程》2003,17(4):605-616

Laboratory experiments are conducted to study the probability distribution of surface elevation for wind waves and the convergence is discussed of the Gram-Charlier series in describing the surface elevation distribution. Results show that the agreement between the Gram-Charlier series and the observed distribution becomes better and better as the truncated order of the series increases in a certain range, which is contrary to the phenomenon observed by Huang and Long (1980) . It is also shown that the Gram-Charlier series is sensitive to the anomalies in the data set which will make the agreement worse if they are not preprocessed appropriately. Negative values of the probability distribution expressed by the Gram-Charlier series in some ranges of surface elevations are discussed, but the absolute values of the negative values as well as the ranges of their occurrence become smaller gradually as more and more terms are included. Therefore the negative values will have no evident effect on the form of t  相似文献   

Effect of Sample Disturbance on Unconfined Compression Strength of Natural Marine Clays   总被引：7，自引：0，他引：7  

刘汉龙  洪振舜 《中国海洋工程》2003,17(3)

1 .IntroductionCoastalstructuresoftenencountersettlementandstabilityproblemsofsoftmarinefoundation (Liuetal.,1 999;Zhouetal.,2 0 0 0 ;Liuetal.,2 0 0 3) .Manyresearchershaveillustratedthatnaturalmarineclaysaregenerallysubjectedtotheeffectsofsoilstructureduringtheirdepositionalandpost depositionalprocesses (Zhangetal.,1 995;Hongetal.,2 0 0 3a ;2 0 0 3b) .Thesoilstructureofnat uralmarineclaysiseasilydamagedduringsamplingandhandlingbecausenaturalmarineclaysgeneral lyhavehighwatercontentandlowsti…  相似文献   

Finite Element Analysis of Deformed Legs of Offshore Platform Structures     

LIU  Chuntu 《中国海洋工程》2002,16(3):311-320

The element stiffness matrix of the equivalent beam or pipe element of the deformed leg of the platform is derived by the finite element method. The stresses and displacements of some damaged components are calculated, and the numeri-cal solutions agree well with those obtained by the fine mesh finite element method. Finally, as an application of this method, the stresses of some platform structures are calculated and analyzed.  相似文献   

Three Dimensional Baroclinic Numerical Model for Simulating Fresh and Salt Water Mixing in the Yangtze Estuary   总被引：1，自引：5，他引：1  

ZHENG  Jinhai 《中国海洋工程》2002,16(2):227-238

For simulating fresh and salt water mixing in estuaries, a three dimensional nonlinear baroclinic numerical model is developed, in which the gradients of horizontal pressure contain the gradient of barotropic pressure arising from the gradi-ent of tidal level and the gradient of baroclinic pressure due to the gradient of salinity. The Eulerian-Lagrangian method is employed to descretize both the momentum equations of tidal motion and the equation of salt water diffusion so as to im-prove the computational stability and accuracy. The methods to provide the boundary conditions and the initial conditions are proposed, and the criterion for computational stability of the salinity fields is presented. The present model is used for modeling fresh and salt water mixing in the Yangtze Estuary. Computations show that the salinity distribution has the characteristics of partial mixing pattern, and that the present model is suitable for simulalion of fresh and salt waler mixing in ihe Yanglze Esluary.  相似文献   

Experimental Investigation on Element Immersing Process of Immersed Tube Tunnel     

ZHOU  Yu   《中国海洋工程》2001,(4):531-540

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刚臂式单点系泊系统在波浪作用下的链力分析     

海工科研组 《海洋学报》1980,2(1):136-147

第一个刚臂式单点系泊储油装置(SBS)于1974年在突尼斯建成,以后在各地又建成了很多个这类装置,据报导其使用效果是令人满意的[1,2].为了发展我国海洋石油勘探、开发的科学技术,在海洋石油研究所的协助下,我们对这种系泊系统进行了波浪模型试验研究,本文在试验成果的基础上,主要研究单点浮筒多链系统的静力特性和波浪要素、水深等对链力的影响,还研究了减小中链力的措施.  相似文献   

Determination of Partial Factors of Breast Wall on Top of Sloping Breakwater     

Lu Jianghua Xie Shileng Engineer  Planning  Design Institute for Water Transportation  Ministry of Communications  Beijing Professor  Senior Engineer  First Design Institute of Navigation Engineering  Ministry of Communications  Tianjin 《中国海洋工程》1996,(4)

- By applying the theory of structural reliability, reliability analyses for the stability of a breast wall on the top of a sloping breakwater are carried out. Based on the analyses, the method for determining partial action / load factors and partial resistance factors of breast walls is expounded, and the design expressions with partial factors are given. The values of partial action / load factors and partial resistance factors are recommended preliminarily according to the computation for breast walls with typical cross-sections.  相似文献   

Calculation of Wave Pressure and Pressure Spectrum for Perforate-Pipe Breakwater   总被引：1，自引：0，他引：1  

Li Chunzhu  Shi Hongda  Yu Dingyong Wang Aiqun Professor  Engineering College  Ocean University of Qingdao  Qingdao Lecturer  Engineering College  Ocean University of Qingdao  Qingdao Senior Engineer  Engineering College  Ocean University of Qingdao  Qingdao 《中国海洋工程》1997,(1)

Standing waves are formed due to the reflection when waves meet vertical wall,thereforestrong structures are needed to keep the wall stability under the serious wave attack.For the improvementof the working condition and increase of the stability of the wall,the lower reflecting breakwaters have at-tracted close attention Reports mostly from Japanese researchers are often concerned with the wall ofcaisson equipped with open windows.In this paper a kind of hollow-pipe perforated breakwater is exam-ined which waves may partially perforate into the harbour basin.The wave in front of the wall can onlyform partial standing wave and wave force is reduced obviously.And the theoretical calculation of waveforce and analysis of wave force spectrum are all derived.Comparison between the results from theoreticalcalculation and hydraulic modeling shows reasonable agreement.  相似文献   

Application of the first internal transcribed spacer (ITS-1) of ribosomal DNA as a molecular marker to population analysis in farrer’s scallop Chlamys farreri     

YU Ziniu  WEI Xiaohua  KONG Xiaoyu  YU Shanshan. Laboratory of Applied Marine Biology  South China Sea Institute of Oceanology  Chinese Academy of Sciences  Guangzhou  China. Key Laboratory of Mariculture of Ministry of Education  Ocean University of China  Qingdao  China 《海洋学报(英文版)》2007,(1)

1 IntroductionFarrer’s scallopChlamys farreriis a nativescallop species occurring along the northern coast ofChina, the Democratic People’s Republic of Korea(DPRK), Korea and Japan (Wang et al., 1993).It has been one of the major species in scallop aqua…  相似文献   

Initial Stable State of Ocean Floor Deposits     

洪振舜  石名磊 《中国海洋工程》2004,18(3):469-476

Extensive oedometer tests and physical tests have been conducted on remoldod and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a straight line in the bilogarithmin In(1 e)∽lg p plot. The initial effective stress corresponding to the initial void ratio is determined by extrapolation of the bilogarithmic compression line. This new way of extrapolating oedometer test data to the initial void ratio overcomes the difficulty of measuring the residual effective stress of soils in the remolded state. The initial stable compression line of ocean floor deposits under different deposition environments corresponds to the compression line at the sensitivity equal to one. This initial stable compression line obtained in this study is consistent with the available compression line at the sensitivity equal to one which is proposed based on the experimental data of remolded undrained strength and the theoretical concept of Cam-clay critical state line.  相似文献