| The problem of water entry impact of the marine structure is widely existed in Naval Architecture and Ocean Engineering, and the research of water entry impact for structure design has been important for more than 70 years. When ships sail in the foul wave, both the bow and the stern would impact on water surface continually, and there will be great instantaneous pressure on structure surface which can lead to serious damage. So the research of impact pressure as well as it's characteristic is practically important for structure design and safety.In this thesis, the finite element software ANSYS/LS-DYNA is used to simulate two-dimensional water entry problem of marine structure in common use, and the analysis of impact pressure as well as the response of structure is done according to the simulation. Including:1,According to prehuman's research, we have known the general situation of water entry problem in and abroad, as well as digested and absorbed the existing theory. Then the basic theory of two-dimensional water entry problem of flat-bottom and wedge-shaped structure is given.2,The two-dimensional water entry of flat-bottom marine structure is simulated, and the impact pressure as well as it's distribution is gained. Then we discuss the effects of velocity and mass to impact pressure, and the effects of elasticity (including thickness of the flat bottom,elastic modul and flexual rigidity) to the response of structure.3,The two-dimensional water entry of wedge-shaped,U-type marine structure and bulbous bow is simulated. We gain the impact pressure as well as it's distribution, the pressure variety of liquid and the rise of free surface. Then we discuss the effects of angle to the peak impact pressure, and compare the pressure variety between flat-bottom and U-type structure. In the end, we gain a lot of significative conclusions.
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