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991.
Xu Xiao Senior
Engineer River Harbour Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1995,(1)
A preliminary study on the distribution of sediment transport and siltation within a semi-closed harbour as well as the factors affecting the siltation has been made with a suspended sediment model, in which the Lianyungang port is used as the prototype. Based on the work, this paper describes a tubid water experiment within a typical excavated harbour basin. According to the experimental results some expressions for predicting the average siltation amount for semi-closed harbour basins by means of dimensional analysis have been proposed, with tidal features, harbour geometry and properties of sediment taken into account. Through comparing the calculated results with the laboratory and field measured data, it has been shown that the expressions presented in this paper are reasonable. 相似文献
992.
Dou Guoren
Academician of Chinese Academy of Sciences Honorary Director of Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1996,(1)
- Turbulent flow is a basic form of fluid motion widely observed in nature. In hydraulic engineering, especially in the study of sediment movement, turbulence is a key problem. In this paper, based on the stochastic theory of wall turbulence developed by the author and the results by other investigators, fluc-tuation and mean structures and drag coefficient for Newtonian and drag reduction flows in all states (laminar, transitional, turbulent) and in all regions (smooth, transitional, rough) are theoretically discussed in detail. General laws for laminar and turbulent flows obtained by the author are verified by the experimental results obtained by others, and there is good agreement between them. 相似文献
993.
He Guangne Yang Bin Wen Nai
Professor Dalian University of Technology Dalian Engineer Design Research Institute of Shanghai Harbour Engineering Shanghai . Lecturer Dalian Fisheries College Dalian 《中国海洋工程》1996,(1)
The stability of slope is affected by a number of factors, some of which have not only random property but also fuzzy characteristic. Therefore, the analysis of slope stability is really an uncertain problem. The customary safety factor does not in reality reflect stability scientifically, quantitatively and practically. In order to obtain more practical results, the slope stability is treated as a fuzzy random event for the evaluation of its fuzzy probability. Finally, the seismic stability of an existing coastal embankment is analyzed by means of the suggested fuzzy probabilistic method. It may be seen that the results of analysis can more fully represent the numerical assessment of the degree of slope seismic stability. 相似文献
994.
995.
Local Scour Around Piles Under Wave Action 总被引:1,自引:0,他引:1
The model tests are performed with regular waves, and the effect of wave height, wave period, water depth, sediment size and pile diameter is evaluated. The shape and size of local scour around piles are studied. There are three typical scour patterns due to wave action. It is found that a relationship exists between the erosion depth and the wave number. An empirical formula of the maximum local scour is thus derived. 相似文献
996.
Wang Jianyi Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1992,(1)
This paper describes the design of a perforated caisson breakwater and presents the results of model test. Tests with regular and irregular waves have demonstrated that the perforated caisson breakwater has the advantages of low reflection coefficient, good wave-absorbing performance, relatively small wave height in front of the breakwater, and small amount of overtopping. Analyses have been made of the coefficient of reflection, wave height in front of the breakwater, and wave overtopping. Relevant figures and tables are presented for reference. 相似文献
997.
1. INTRODUCTION When inspecting the Choukoutien area in October 1933, under the direction of the late Dr. Davidson Black, the workmen brought to the attention of the members of the Cenozoic Laboratory a fossiliferous site which had 相似文献
998.
1. INTRODUCTION When inspecting the Choukoutien area in October 1933, under the direction of the late Dr. Davidson Black, the workmen brought to the attention of the members of the Cenozoic Laboratory a fossiliferous site which had 相似文献
999.
INTRODUCTION The part of the Lower Huangho Valley with which this paper deals is bounded on the west by the T'ungkuan Bend where the Loho (洛河) and the Weiho (渭河) join their master stream and on the east by the Sanmen Rapids (三门急流). The area which lies between P'ingluhsien (平陆县). 相似文献
1000.