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排序方式: 共有1294条查询结果,搜索用时 15 毫秒
931.
Zhang Fugui Ge Zhijin
Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1996,(4)
- Rubble mound breakwater, one of the protection structures, has been widely used in coastal and port engineering. Block stones were first used as its armor layer, and its use was limited to shallow sea areas where there is no large waves. Since the specially-shaped armor unit was developed, the rubble mound breakwater has become the main sort of the protection structures, which can be used in deep water zones where storm sometimes occurs. Owing to severe and complex surrounding conditions, the rubble mound breakwater failure sometimes occurs, thus the study on the causes of failure is of great importance. In the present study some breakwater failures at home and abroad are illustrated and the causes of failure are investigated from the point of view of design, test, construction and maintenance. 相似文献
932.
933.
1 .IntroductionWiththedevelopmentofexploitationofmarineresources ,theconstructionofoffshorestructuresdevelopsrapidly ,suchasmarineoilplatforms ,deep waterbreakwaters ,marinebridges ,largehar bors,etc .Thesestructureswillchangesurroundingwaveandcurrentconditionsandleadtolocalscourofseabed ,resultinginstructuraldamage .Therefore ,localscouraroundmarinestructuresaswellastheirprotectionhasdrawnmuchattentionfromrelativeengineeringfields .Manyscholarshaveconduct edtheoreticalanalysisandexperimentals… 相似文献
934.
Hu Yuchu Wu Shaozhang Lu Liyun Senior Engineer Nanjing Hydraulic Research Institute Nanjing
Professor Senior Engineer Nanjing Hydraulic Research Institute Nanjing
Assistant Engineer Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1992,(4)
The concrete blocks used on a jetty in Shanghai were made in 1909 and 1910. Having been exposed in nature for 80 years, now there are 4600 pieces of blocks left on the jetty. Comprehensive inspections, such as external appearance examination, core-drilling of concrete blocks, ultrasonic detection, nuclear densimeter inspection and in-door and out-door chemical analysis, show that 75% of the blocks are of the rebound number of 21 - 23, and the saturated limit compressive strength and dry limit compressive strength of 10MPa; the carbonized depth of concrete is 1 - 2 mm. Compared with the state of the jetty in 1968, already used for 60 years then, the jetty is expected to serve another 40 years or more after being repaired. 相似文献
935.
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
936.
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
937.
Wang Nianxiang Wei Rulong Engineer Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing Prof. Senior Engineer Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1994,(2)
-A nonlinear model for the stress-strain behaviour of normally consolidated clays is presented based on the experimental results. It is indicated that the volume strain under pure shear is a power function of stress ratio and the normalized stress-strain curve is a standard hyperbola. According to the model, the coefficient of pore pressure induced by shear stress and the critical stress ratio which governs the influence of the negative dilatancy are suggested. It is shown by some triaxial tests that the proposed model can be used to study the negative dilatancy and to describe the stress-strain-pore pressure adequately for soft clays. 相似文献
938.
Mao Zhixiang Yan Peilan Huang Jianwei Dai Xiankai Han Naibing Chai Zhifang Qian Qinfang Ma Shulan Ma Jianguo Engineer Nanjing Hydraulic Research Institute Nanjing
Senior Engineer Nanjing Hydraulic Research Institute Nanjing
Associate Researcher 《中国海洋工程》1991,(3)
A new method of Neutron Activation Analysis (NAA) for sediment movement study is presented in this paper. Through analyzing the natural sediment, the information about natural tracing agents has been obtained, which can show the direction of sediment movement and relative discharge of sediment transportation. Test results in some areas, such as Shantou Harbour and Hangzhou Bay, are in good agreement with those from normal hydrologic measurements and some results are not obtainable with the latter. The NAA is economical, practical and reliable, and should be widely used in engineering practice. 相似文献
939.
Wang Zhaojing Zhang Ling
Senior Engineer Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing Engineer Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1996,(1)
- In order to verify the theoretical design and computation of a new type of platform, laboratory model test of the superficial sliding of the platform is carried out. Test results show that the requirement for the stability of the platform can be satisfied, and the API-82 criterion can be met. It is also suggested that, in order to enhance the stability of the platform, a buried- pad with porous holes and a long apron-board should be adopted in the design of the new type of platform. 相似文献
940.
Experimentally validated numerical method for the hydrodynamic design of horizontal axis tidal turbines 总被引:1,自引:0,他引:1
W.M.J. Batten A.S. Bahaj A.F. Molland J.R. Chaplin Sustainable Energy Research Group 《Ocean Engineering》2007,34(7):1013-1020
Although a lot can be learnt from technology transfer from wind turbines and ship propellers, there have been a few experiments investigating marine current turbines. As a result, a study has been carried out on the power, thrust and cavitation characteristics of 1/20th scale model of a possible 16 m diameter horizontal axis tidal turbine. Cavitation tunnel experiments for different blade pitch settings have been compared with simulations based on a developed blade element-momentum theory. This theory has been shown to provide a satisfactory representation of the experimental turbine performance characteristics. As an example application, the developed theory has been used to design possible horizontal axis tidal turbines for the tidal flows around Portland Bill. The results show that there is a clear balance between design loads and optimisation of energy yields. 相似文献