Dynamic Response of Fluid-Single Leg Gravity Platform-Soil Interaction System     

Kuang Zhiping Cao Guoao Dr. Lecturer  Tongji University  Shanghai Dr. Professor  Tongji University  Shanghai 《中国海洋工程》1993,(2)

- An approximate method is presented to investigate the earthquake response of the fluid-single leg (shortened for S. L.) gravity platform-soil interaction system. By assuming a suitable form of the velocity potential of the radiation waves and by using the motion equation and the boundary conditions, the unknown coefficients can be obtained. Thereafter the function of frequency for the interaction system may also be obtained. In this paper, the difference of the system dynamic response between rigid foundation is analyzed and the influences of the various foundation geometric dimension and the various water-depth on the hydrodynamic loading and dynamic response of the system is illustrated.  相似文献   

Fuzzy Risk Analysis of Harbour Engineering Investment by Hierarchy System Approach     

Lin Shaopei  Zhang Zhongming Professor  Civil  Architectural Engineering Dept.  Shanghai Jiao Tong University  Shanghai Lecturer  Civil  Architectural Engineering Dept.  Shanghai Jiao Tong University  Shanghai 《中国海洋工程》1992,(1)

The present risk analysis model of engineering investment is built by fuzzy hierarchy approach under the assumption of maximizing the revenues of the project during its whole life cycle of operation. It can reasonably be expressed by a system evaluation analysis. As a matter of fact, the system, aimed by its system goal can be modelled by a set of factors, constitutively structured by certain links between them, to form a factorial network chart, which represents the essentials of the system behaviours, the nodes of which represent the factors concerned. The weight distribution between factors located at the same level can be determined by the eigen-value problem of a "pair comparison" relation matrix. The weight distribution of factors at each level is successively manipulated until the fuzzy synthetic risk assessment. As an example of risk analysis of engineering investment, a harbour construction project is presented for illustration.  相似文献   

Influence of Energy Directional Spread on Wave Spectral Refraction     

Li Yucheng Professor  Dept. of Civil Engineering  Dalian University of Technology  Dalian 《中国海洋工程》1992,(2)

Pierson- Moskowitz Spectrum, JONSWAP Spectrum as well as Bretschneider- Mitsuyasu Spectrum are used in this paper for analyzing the influence of wave energy directional spread on refraction of wave spectrum due to both current and topography of sea bed. The author's calculation indicates that such kind influence on the characteristic value of wave height as well as the average direction of wave energy propagation can not be ignored.  相似文献   

Some Considerations in Design and Construction of the Wei-Liu Water Supplying Submarine Pipeline     

Fan Yunlin  Chang Dezhi Associate Professor  Dept. of Ocean Eng.  Tianjin University Engineer  Construction Committee of Weihai City  Shandong Province 《中国海洋工程》1991,(4)

The Wei- Liu water supplying submarine pipeline is at present the longest one of the kind in China. It is about 4 kilometers long from Weihai City to Liugong Island in Shandong province. It took only half a year to design and construct it. The project was of a high economic efficiency and some practical experiences were achieved. In this paper a general introduction to the design and construction of this pipeline is presented and such problems as the stability of the pipeline in very soft clay, design of curved slide for launching and estimation of dragging forces are expounded.  相似文献   

On the Spectral Moments of Wind Waves   总被引：2，自引：0，他引：2  

LI  Luping 《中国海洋工程》2002,16(1):135-140

In order to obtain high order spectral moments, the residual moment , as proposed by De-nis, is presented for approximate estimation of spectral moment Glazman's partial averaging idea isdiscussed. It is pointed out that Glazman's method and definition of non-dimensional spectral moment can not be used to es-timate spectral moments for engineering purposes and that method is not supported by theory and computation. The non-dimensional spectral moment of PM spectrum, which should be expressed as is related to wind speed. The0 - 8th moments of PM spectrum are estimated for wind speeds of 10, 20 and 30 m/s and some discussions are given.  相似文献   

Hydrodynamic Forces on Inclined Cylinder due to Waves with Crossing Current     

Li Yucheng  Kang Haigui Sun Dapeng Professor  Dalian University of Technology  Dalian Lecturer  Dalian University of Technology  Dalian Lecturer  Dalian University of Technology  Dalian 《中国海洋工程》1991,(2)

Based on Morison's Equation and linear wave theory, hydrodynamic forces acting on inclined cylinders due to waves and crossing current at an angle of a, are analyzed. A method for calculating exciting forces is proposed. Experimental results show that the proposed method in this paper is feasible and can be used in engineering practice.  相似文献   

Investigation on the Performance of Articulated Buoys     

Feng Bojun  Huang Guoliang Liu Tianwei Associale Professor  Shanghai Jiao Tong University  Shanghai Engineer  Shanghai Jiao Tong University  Shanghai 《中国海洋工程》1995,(4)

Articulated buoys become more and more popular by the marine management departments as a new type of aids to navigation, for they possess an excellent hydrodynamic performance with small static heel angle in wind and current and small rolling in wave and accurate position. The structure of articulated buoys and calculation method of their hydrodynamic performance are introduced in this paper. A scries of experiments has been conducted in the State Key Laboratory of Ocean Engineering of China and useful results achieved for providing a design optimization basis.  相似文献   

A Numerical Computation Method for Current Field in Tidal zone     

Wei Shoulin Xiao Rong Professor  Ocean University of Qingdao  Qingdao  . Teaching Assistant  Ocean University of Qingdao  Qingdao 《中国海洋工程》1994,(1)

- In this paper, a numerical computation method is developed for the computation of current field in the tidal zone, using the well-point method and ADI method. The computational results agree well with the general variation of current field in the tidal zone.  相似文献   

Analytical Study on Transmission and Reflection of Non-Linear Shallow Water Waves     

Miao Guoping Liu Yingzhong Professor  Dept. of Naval Architecture  Ocean Engineering  Shanghai Jiao Tong University  Shanghai 《中国海洋工程》1991,(1)

The analytical study is made by using the method of matched asymptotic expansions on the transmission and reflection of solitary waves and cnoidal waves on two-dimensional floating bodies. The solutions give explicitly the variation pattern of the transmitted waves and the characteristics of the reflected waves, including the wave profile, amplitude, phase shift and evolution. The effects of the gap between the body and the sea bottom on the transmission and reflection of those waves are also discussed.  相似文献   

A Finite Element Solution of Wave Forces on Submerged Horizontal Circular Cylinders   总被引：2，自引：0，他引：2  

赵明  滕斌  谭丽 《中国海洋工程》2004,18(3):335-346

In this paper, a numerical model is established for estimating the wave forces on a submerged horizontal circular cylinder. For predicting the wave motion, a set of two-dimensional Navier-Stokes equations is solved numerically with a finite element method. In order to track the moving non-linear wave surface boundary, the Navier-Stokes equations are discretized in a moving mesh system. After each computational time step, the mesh is modified according to the changed wave surface boundary. In order to stabilize the numerical procedure, a three-step finite element method is applied in the time integration. The water sloshing in a tank and wave propagation over a submerged bar are simulated for the first time to validate the present model. The computational results agree well with the analytical solution and the experimental data.Finally, the model is applied to the simulation of interaction between waves and a submerged horizontal circular cylinder.The effects of the KC number and the cylinder depth on the wave forces are studied.  相似文献