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41.
近海工程环境应用中各种风资料的平均时间分析 总被引:5,自引:0,他引:5
本文从近海工程设计应用的需要出发,对于通常使用的不同来源的测风资料平均时间进行了分析,这些资料来源包括:岸边及近海探查与生产设施上的气象台站、天气观测船、浮标、商船气象报、从受灾情况估计出的极大风速以及动力诊断模型估计出的海面风速。 相似文献
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The rain-flow counting method is widely used to compile the fatigue load spectrum. The second stage counting of the rain-flow method is a troublesome process. In order to overcome this drawback, the rain-flow and reverse rain-flow counting method is proposed in this paper. In this counting method, the rule for counting of the rain-flow method is modified, so that the sequence of load-time need not be adjusted. This is a valid and useful method to count cycles and compile the load spectrum and it can be widely used in ocean engineering. 相似文献
44.
A novel method for prediction of the load carrying capacity of a corroded reinforced concrete beam (CRCB) is presented in the paper. Nine reinforced concrete beams, which had been working in an aggressive environment for more than 10 years, were tested in the laboratory. Comprehensive tests, including flexural test, strength test for corroded concrete and rusty rebar, and pullout test for bond strength between concrete and rebar, were condueted. The flexural test results of CRCBs reveal that the distribution of surface cracks on the beams shows a fractal behavior. The relationship between the fractal dimensions and mechanical properties of CRCBs is then studied. A prediction model based on artificial neural network (ANN) is established by the use of the fractal dimension as the corrosion index, together with the basic intbrmation of the beam. The validity of the prediction model is demonstrated through the experimental data, and satisfactory resuits are achieved. 相似文献
45.
从风暴潮、黄河口治理、海水地下入侵与咸水侵染、海岸及沿海污染、沿海滩涂与黄河三角洲开发、海上交通和港口发展、海岸和海上石油开采、海岸工业基地建设、沿海旅游和海岛开发 ,以及沿岸淡水资源开发与海水利用等 1 0个方面 ,对山东省海岸工程的可持续发展问题进行了分析和讨论 ,并针对具体问题 ,提出了解决可持续发展问题的对策与措施。 相似文献
46.
底部浮泥表层推移速度分布的ADCP—GPS估测方法 总被引:3,自引:0,他引:3
ADCP对底跟踪走航观测的流速数据中包含水体底部浮泥、底沙运动信息,对比GPS定位方法算出的水体流速数据可以分离出浮泥相对于GPS定位的运动信号,从而达到对底质推移观测的目的。 相似文献
47.
Two-Dimensional Mathematical Model of Tidal Current and Sediment for Oujiang Estnary and Wenzhou Bay 总被引:1,自引:0,他引:1
A 2-D mathematical model of tidal current and sediment has been developed for the Oujiang Estuary and the WenzhouBay. This model accomodates complicated features including multiple islands, existence of turbidity, and significant differ-ence in size distribution of bed material. The governing equations for non-uniform suspended load and bed load transport arepresented in a boundary-fitted orthogonal curvilinear coordinate system. The numerical solution procedures along with theirinitial conditions, boundary conditions, and movable boundary technique are presented. Strategies for computation of thecritical condition of deposition or erosion, sediment transport capacity, non-uniform bed load discharge, etc. are suggested.The model verification computation shows that, the tidal levels computed from the model are in good agreement with the fielddata at the 18 tidal gauge stations. The computed velocities and flow directions also agree well with the values measuredalong the totally 52 synchronously observed verticals distributed over 8 cross sections. The computed tidal water throughputsthrough the Huangda‘ao cross section are close to the measured data. And the computed values of bed deformation fromYangfushan to the estuary outfall and in the outer-sea area are in good agreement with the data observed from 1986 to 1992.The changes of tidal volumes through the estuary, velocities in different channels and the bed form due to the influence of thereclamation project on the Wenzhou shoal are predicted by means of this model. 相似文献
48.
Wei Rulong Prof. Senior Engineer Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1994,(1)
-The shear strength and deformation properties of soft clay are discussed first. Then some methods for predicting the performance of soft clay foundation are proposed. Finally, case histories are presented to illustrate some discussed aspects of soft clay. 相似文献
49.
1 .Introduction Submarine pipelines are one of the safest and the least environmentally disruptive means for ma-rine gas or oil transport . With the development of exploitation of submarine oil or gas ,the safety ofsubmarine pipelines has becomethe major … 相似文献
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