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1.
《中国海洋工程》1988,(2)
- This paper briefly introduces the experimental studies on maritime engineering structures with irregular wavemaker system in Nanjing Hydraulic Reseach Institute and discussed the experimental results for wave protection and coast protecting works under the action of regular and irregular waves. The paper also suggests that systematic studies should be carried out of the wave run-up height and the overtopping water volume on the slope of coast protecting works under the action of regular and irregular waves. 相似文献
2.
- Usually, the action of sea ice on offshore engineering structures is one of the controlling loads in cold waters engineering structure design. The reasonable selection of environmental condition and the physical mechanical properties of ice in the region are directly related to the structure design, operation and safety. In this paper, the sea ice force acting on the structure, the physical mechanical properties of ice and the selection of parameters in calculation are discussed. Some suggestions are proposed as to the calculation of various kinds of ice loads acting on the structure. 相似文献
3.
The large cylinder is a new-type structure that has been applied to harbor and offshore engineering. An analytic method of the relationship between loads and the structure displacement is developed based on the failure mode of deep embedded large cylinder structures. It can be used to calculate directly the soil resistance and the ultirnate bearing capacity of the structure under usage. A new criterion of the large cylinder structure, which discriminates the deep embedded cylinder from the shallow embedded cylinder, is defined. Model tests prove that the proposed method is feasible for the analysis of deep embedded large cylinder structures. 相似文献
4.
1 IntroductionIn the Equatorial Pacific, due to the difference between the atmospheric circulation and air-sea interaction, the near-surface seawater heat structure in the eastern and western Pacific presents two ℃obviously different characteristics: warm pool ( > 28 ) in the western equatorial Pacific and cold ℃tongue ( < 24 ) in the eastern equatorial Pacific. The water bodies of these two heat structures would give rise to change in spatial distribution under the action of the equato… 相似文献
5.
Hydraulic structures such as groin, longitudinal dike and seawall are common in water conservancy and water transportation engineering projects at home and abroad, which have long been dominated by solid mass structural form. With brush and stone as building materials, this kind of structure has an obvious engineering effect. However, it not only requires huge capital investments, but also has negative impacts on the ecological environment. The suspended flexible dam is an innovative engineering measure, and few theoretical and experimental researches of this type dam can be found at present. This paper studies the mechanism and shape characteristics of this dam and obtains the dynamic equilibrium equation of flexible dam, the float buoyancy expression, and the condition for transformation among three forms of the underwater shape of the dam. The results are valuable in engineering application and can be used as the reference for the future work due to the distinctive design philosophy, the small negative effects on environment and the consistency for sustainable development. 相似文献
6.
《中国海洋工程》1990,(2)
Some offshore structures have configurations as uniform vertical cylinders of equal section. The interaction between the oscillation of them and fluid motion is of importance in many design cases. For those special cylindrical bodies, a new type of local disturbance source is presented in the paper, which, being distributed on the sectional contour of the cylinders together with the known wave source, can be used to estimate the three-dimensional hydrodynamic forces on those cylinders of arbitrary section oscillating in still waters. The solution method both for wave forces and radiation forces is also discussed. 相似文献
7.
《中国海洋工程》1989,(1)
Owing to the reinforcement corrosion, freezing action and external mechanical attack, some reinforced concrete structures of seaport works in China have been suffering severe damages. A survey showed that more than 40 reinforcement seaport structures and tide barriers had been damaged so that they had only a service period of 7 - 25 years. Therefore,the repair task is very heavy. In the present paper, some principles and methods for repairing the reinforced concrete seaport structures are provided and some related technical requirements, materials as well as their preparation and properties are recommended. 相似文献
8.
《中国海洋工程》1987,(3)
- Through the suspension of long samples in sea water and other various corrosion tests, it has been shown that Cr, Si, Cu and Mo added in steel can improve its corrosion resistance in splash zone effectively. Based on this observation, the most suitable chemical compositions of the steel have been selected. This steel produced in semi-industrial scale has good combination of mechanical properties and excellent weldability. Moreover, compared with mild steel, its corrosion resistance in splash zone doubled at least. This steel can be widely applied for ocean engineering structures. 相似文献
9.
In engineering practice,tubular X-joints have been widely used in offshore structures.The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress.In this study,the stress concentration factor distribution along the weld toe in the hot spot stress region for tubular X-joints subject to axial loads have been analyzed by use of finite element method.Through numerical analysis,it has been found that the peak stress concentration factor is located at the saddle position.Thereafter,80 models have been analyzed,and the effect of the geometric parameters of a tubular X-joint on the stress concentration factor has been investigated.Based on the experimental values of the numerical stress concentration factor,a parametric equation to calculate the stress concentration factor of tubular X-joints has been proposed.The accuracy of this equation has been verified against the requirement of the Fatigue Guidance Review Panel,and the proposed equation is found capable of producing reasonably accurate stress concentration factor values for tubular X-joints subject to axial loads. 相似文献
10.
《中国海洋工程》2017,(5)
正Aims and Scope Being an international journal,China Ocean Engineering(COE)takes its prime function as the integration of new research concepts,equipment,technology,materials and structures and other scientific advances within the field of estuarial,coastal,offshore,and deepwatar engineering with particular reference to developments.The Journal is concerned with all engineering aspects involved in the exploration and utilization of ocean resources.Topics regularly covered include research,design and construction of structures(including wharfs,dikes,breakwaters, 相似文献
11.
《中国海洋工程》2017,(3)
正Aims and Scope Being an international journal,China Ocean Engineering(COE)takes its prime function as the integration of new research concepts,equipment,technology,materials and structures and other scientific advances within the field of estuarial,coastal,offshore,and deepwater engineering with particular reference to developments.The Journal is concerned with all engineering aspects involved in the exploration and utilization of ocean resources.Topics regularly covered include research,design and construction of structures(including wharfs,dikes,breakwaters, 相似文献
12.
Marine structures are mostly made of metals and always experience complex random loading during their service periods. The fatigue crack growth behaviors of metal materials have been proved from laboratory tests to be sensitive to the loading sequence encountered. In order to take account of the loading sequence effect, fatigue life prediction should be based on fatigue crack propagation (FCP) theory rather than the currently used cumulative fatigue damage (CFD) theory. A unified fatigue life prediction (UFLP) method for marine structures has been proposed by the authors’ group. In order to apply the UFLP method for newly designed structures, authorities such as the classification societies should provide a standardized load-time history (SLH) such as the TWIST and FALSTAFF sequences for transport and fighter aircraft. This paper mainly aims at proposing a procedure to generate the SLHs for marine structures based on a short-term loading sample and to provide an illustration on how to use the presented SLH to a typical tubular T-joint in an offshore platform based on the UFLP method. 相似文献
13.
《中国海洋工程》2015,(2):313
<正>An Intenuitional Journal Aims and Scopc Being an international journal.China Ocean Engineering takes as its prime funclion the integration of new research concepts,equipment,technology,materials and structures and other scientific advances within the field of cstuarial,coastal.ol Tsliorc,aiul deepvvater engineering with particular reference to developments.The Journal is concerned with all engineering aspects involved in the exploration and utilization of ocean resources.Topics regularly covered include research,design and constructi on of structures(including wharfs,dikes,breakwaters,platforms,mooring systems,etc.),inslrumcntation/testing(physical model and numerical model),wave dynamics,sedimentation,structura I/stress analysis,soil mechanics,and material research, 相似文献
14.
The sequence of biocalcarenites occurred on Shidao Island, the highest one among the Xisha Archipelago, is characterized by the alternation of cross-beddings and parallel beddings, which, owing to the misinterpretation of the sedimentary structures, has caused some controversies.Three kinds of boundary surfaces have been found in the sequence: the first-order boundaries marked with the occurrence of paleosols which is nearly horizontal; the second-order boundaries between dune deposits and interdune deposits, formed by the climbing of the dunes and interdunes under the action of NE-trade wind; and the third-order boundaries of cosets inclining exclusively windward. The dune deposits have well-preserved cross-beddings on a large scale, while the interdune deposits show roughly paralled bedding.In conclusion, the coexistence of the three boundary surfaces and the dune and interdune deposits marks the feature of the eolian biocalcarenites. The eolian deposits started from 3200 yr BP when sea level was low 相似文献
15.
The modified hybrid element method (MHEM) is utilized to predict and analyze wave forces on arbitrarily shaped multiple bodies. This method can be applied to waves of all water depths, i. e. shallow, intermediate, and deep waters, on slowly varying seabed. The MHEM employs the ICCG method to save CPU and storage, thus the computation of wave forces for large multi-body systems can be carried out on microcomputers. Numerical results of the present method are compared with experimental data and other solutions. It is shown that the MHEM provides more accurate solutions of the wave forces than other numerical methods do. Therefore, the methodology presented herein can be used in the design of coastal and ocean structures. 相似文献
16.
《中国海洋工程》1998,(4)
China Ocean Engineering takes as its prime function the integration of new research concepts,equipments,technology,materials and structures and other scientific advances within the field of ocean engineering,withspecific reference to develoments in China.The Journal is concerned with all engineering aspects involved in theexploration and utilization of ocean resources,such as offshore engineering,coastal engineering,dive and sal-vage,utilization of marine energy resources and underwater engineering. Topics regularly covered include design and construction of structures(including wharfs,dike,breakwa-ters,platforms,mooring systems,etc.),instrumentation/testing(physical model and numerical model),materi-al research,structural/stress analysis,soil mechanics,sedimentation and wave dynamics. 相似文献
17.
《中国海洋工程》1987,(4)
- At the sites of the harbours along the coast of China, especially in the vicinity of the mouth of the Yellow River, the Yangtze River and the Pearl River, the soil strata often consist of recently deposited alluvial sediment. Therefore, under the foundations of harbour engineering structures there are always soft clays of considerable thickness. In this paper, the definition of soft clay is at first given according to the Chinese Foundation Code of Harbour Engineering. Then the physical and mechanical properties of some soft clays at the sites of harbour along the coast of China are summarized. These soft clays are classified into four types according to their physico-mechanical characteristics: very soft clay (mud), soft (muddy) clay, soft (muddy) silty clay and very soft clay (mud) mixed with lumps of sand. It is seen from the collected data that the physico-mechanical characteristics for soft clay of the same type at various sites along the coast of China are very similar, which implies that these soft clays may be formed from the similar geological origin and in similar environmental condition. It is well known that the soft clay with such unfavourable engineering properties as high water content, low shear strength, high compressibility and low permeability, is a rather weak foundation for structures, hence there would be frequently some problems happened during the construction of structure on it. However, these problems more or less can be avoided, provided that the soft clay strata have been explored, tested and analyzed carefully and appropriate measures are taken during construction. The problems usually encountered in the construction on soft clay are deformation and stability. The experiences and lessons learned on these respects in China are illustrated with 10 case histories of different types. 相似文献
18.
Characteristics and distribution patterns of reef complexes on the carbonate platform margin in deep water areas: the western South China Sea 总被引：2，自引：1，他引：1
CHEN Ping LI Xushen WANG Yahui LU Yongchao ZHONG Zehong CHEN Lei ZUO Qianmei MA Yiquan WANG Chao DU Xuebin 《海洋学报(英文版)》2015,34(10):71-80
As a potential oil and gas reservoir, reef complexes have been a research focus from petroleum geologists for a long time. There are favorable conditions for the development of reef complexes in the South China Sea; however, their internal structures, evolution and distribution are still poorly understood. Based on 2D and 3D seismic data, the internal structures and evolution patterns of the reef complexes on the carbonate platform margin in the deep water areas over the western South China Sea were studied in detail. The result shows that two types of reef complexes, i.e., fault controlling platform margin reef complexes and ramp reef complexes have been developed in the study area. The reef complexes have independent or continuous mound or lenticular seismic reflections, with three internal structures (i.e., aggrading, prograding and retrograding structures). There are different growth rates during the evolution of the reef complexes, resulting in the formation of catch-up reefs, keep-up reefs and quick step reefs. The study also reveals that different platform margin reef complexes have different internal structures and distributions, because of the different platform types. These results may be applied to the exploration and prediction of carbonate platform margin reef complexes in other areas that are similar to the study area. 相似文献
19.
《中国海洋工程》1999,(1)
China Ocean Engineering takes as its prime function the integration of new research concepts,equipments,technology,materials and structures and other scientific advances within the field of ocean engineering,withspecific reference to developments in China.The Journal is concerned with all engineering aspects involved inthe exploration and utilization of ocean resources,such as offshore engineering,coastal engineering,dive andsalvage,utilization of marine energy resources and underwater engineering. Topics regularly covered include design and construction of structures(including wharfs,dike,breakwa-ters,platforms,mooring systems,etc.),instrumentation/testing(physical model and numerical model),materi-al research,structural/stress analysis,soil mechanics,sedimentation and wave dynamics. 相似文献
20.
I~IOXdifferent tabes of submerged structures restricting wave development are extensively appliedin coastal and barber engineering. Generally speaking, the submerged structures are classified intothree types (see Fig. 1 ): a submerged horizontal plate (fixed submerged structure), a submergedbreakwater (rectangular or trapezoidal) and a step-take structure (toPOgraphy). In order to get aclear understanding of the characteristics of wave motion around submemed structures, manyFig. 1. Fol'InS… 相似文献