| In recent years, the recourse exploitation has invaded to the ocean, especially direction to the blue water has become necessary. With technological advancement and the persistent raise of crude oil price human naturally turn their steps to ocean area in deep water. It has been the inevitable trends to make exploiter of oil/gas from offing to blue water for our country.As to drilling, marine riser has being become a major problem because of the troublesome working environment caused by deepwater. In order to design and use riser freely, it is necessary and important to study riser's working state and complex loadings on it with static and dynamic analysis.This paper clearly introduces wave theory in structure hydrodynamics as foundation and discusses the fundamental equation and derivation in linear wave theory and Stokes' wave theory and finally introduces calculation means of wave force of small and large members in ocean engineering structure. When calculating the small volume wave loads, Morison formulation, the selection of wave theory and the confirmation of drag coefficient and mass coefficient is introduced.The second part of this paper makes as amplified modeling analysis with FEA software ANSYS, and ascertains the basic parameter of drilling riser; In addition the condition and the environmental loads of the riser are given. And then this paper presents a pipe-soil model for the analysis on the contact between the bottom of the drilling riser and the soil by using finite element analysis software. Based on the new modal, the contrast of two modals at different water depth is analyzed; the modes of drilling riser under different conditions of soil are investigated numerically; the different depths of fixed support under the soil are analyzed; at last, the current induced vibration is discussed. It would achieve more precise results than on the simplification model. In addition, the conclusions providing a scientific basis for the strength design of drilling riser.
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