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排序方式: 共有2391条查询结果,搜索用时 140 毫秒
971.
Zhou Jiabao Zhang Jiachang Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1992,(1)
-The effect of wave group on wave run-up on a slope dike is mainly discussed in this paper. Two simulating methods of wave group and their applications in laboratory are introduced. Synthesizing the research results of wave run-up on a slope dike, the effect of wave group on wave run-up on a slope dike in coastal protection engineering is studied as the main point. 相似文献
972.
Zhu Guangyu Lu Tongsheng Tang Nianci Zai Jinzhang . Senior Engineer Research Institute of the Third Navigation Engineering Bureau Ministry of Communications Shanghai
. Lecturer Dept. of Communications Transportation Engineering Southeast University Nanjing
. Professor Dept. of Communications Transportation Engineering Southeast University Nanjing
. Associate Professor 《中国海洋工程》1991,(4)
Field measurements of driving resistances and heights of soil core during driving were made offshore and onshore of steel pipe piles. Measured data show that the height of soil core varies differently for piles of different diameters with the increase of penetration. Dynamic plugging could be assumed never to occur for steel pipe piles with diameters over 900 mm. Soil resistances at the time of continuous driving (SRD) are back analyzed from blow counts with an empirical distribution of resistances suppported by many early dynamic measurements. A method of predicting SRD is finally suggested. 相似文献
973.
Computational Techniques of 2D Tidal Flow in Estuaries and Bays 总被引:1,自引:0,他引:1
Xin Wenjie
Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1995,(4)
- Some problems in the numerical calculation of tidal flow in estuaries and bays, such as distribution bed roughness, relationship between model moving boundary and water volume balance, remedy of certain shortage under open boundary conditions, smooth transfer of the controlling message for the inner boundaries of nested model, can not be solved usually by means of the fundamental equations and computing mode adopted in the numerical model, but can be done by the measures which not only satisfy the physical features but also are convenient for operation. Based on the calculated samples of some areas of Modaomen, Lingdingyang and Huangmaohai of the Pearl River Estuary, and Shuidong Bay (a typical barrier- lagoon tidal channel) in Guangdong Province, method and process of calculation for the above mentioned problems are briefly presented in this paper. 相似文献
974.
Numerical Simulation for Refraction-Diffraction of Waves in Water of Slowly Varying Current and Topography 总被引:3,自引:0,他引:3
Hong Guangwen Feng Weibing Xia Qiyi Pan Shaohua
Professor Research Institute of Coastal Ocean Engineering Hohai University Xikang Road Nanjing
Senior Engineer Research Institute of Coastal Ocean Engineering Hohai University Xikang Road Nanjing 《中国海洋工程》1997,(4)
A new numerical finite difference iteration method for refraction-diffraction of waves in waterof slowly varying current and topography is developed in this paper.And corresponding theoretical modelincluding the dissipation term is briefly described,together with some analysis and comparison ofcomputational results of the model with measurements in a hydraulic scale model(Berkhoff et al.,1982).An example of practical use of the method is given,showing that the present model is useful to engineeringpractice. 相似文献
975.
This paper presents the results of a series of studies on the influence of curing conditions onthe strength development of high strength concrete.The 1-,3-,7-,14-and 28-day strengths of four dif-ferent mixes of Grade 75~80 concrete,with or without pulverized fuel ash and/or condensed silica fume,under five different curing regimes were investigated.It is revealed that the curing conditions have signifi-cant influence on both the short term and long term strength development of the concrete and that con-crete mixes of the same grade but containing different mineral admixtures show distinct favour for a cur-ing regime.These results will be helpful for evaluating suitable curing methods for high strength concretewith different mix proportions. 相似文献
976.
Zhu Chengde Senior Engineer China Offshore Oil Development & Engineering Corporation 《中国海洋工程》1993,(4)
- This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface preparation, coating application, as well as coating inspection for four types of major production facilities. 相似文献
977.
Yao Guoquan Ma Zhixiong Ding Bingcan Senior Engineer River Harbor Department Nanjing Hydraulic Research Institute Nanjing Assistant Engineer River Harbor Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1991,(3)
- This paper presents a calculation method for the diffraction of both regular waves and irregular waves of the single directional frequency spectrum behind a single jetty with a theoretical analysis, which has been confirmed through the model experiments, derives a method of computing the diffracted irregular waves behind the single jetty with the theoretical analysis on the basis of computation of the field data and gives the formulas and the figures of the computation of wave diffractions behind the vertical wall or mound single jetties. 相似文献
978.
Unified Water Gravity Wave Theory and Improved Linear Wave 总被引:2,自引:0,他引:2
Fu Yuhua Senior Engineer Structural Engineering Department China Offshore Oil Development Engineering Corp. Beijing 《中国海洋工程》1992,(1)
- Based on Least Square Method, this paper presents variational principle for handling various water gravity wave theories and the unified water gravity wave theory was given. By using this variational principle of unified water wave theory, two kinds of improved linear waves were derived. The first one uses the same boundary conditions which were applied to derive 5-order Stokes wave. The second one uses the accurate boundary conditions (Eqs. 11 and 12). The two improved linear waves were compared with the existing linear wave. 相似文献
979.
Zuo Qihua Yao Guoquan
Engineer Nanjing Hydraulic Research Institute Nanjing
Senior Engineer Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1991,(2)
The second order long waves of the mean water free surface displacement induced by the wave groups over a trench are discussed in this paper. The incident wave groups are supposed to be superposed by 2 linear waves with different amplitudes, phases and slightly different frequencies. Some of the theoretical formulas and numerical results are presented. 相似文献
980.
- This article briefs how to improve the holding power of a drilling vessel's anchor and to remove those unreasonable structures by such a technology - underwater-explosion technology. The article gives details of the structure, characteristics and applications of a rocket-launched anchor; as well as the principle, properties, applications of directional explosion cutting. 相似文献