Ice-induced Vibration Of Conical Structure And Design Of Vibration Isolated Cone

Offshore platform structures are the basic establishment for exploitation oil and natural gas. They are always in atrocious sea environment. As many oil platforms are to be erected at the oceans coved with ice, more and more problems appear. In order to reduce the, response of the platform vibration, some methods and devices must be found. From the view of design, there are mainly three solutions to depress this vibration: the first way is to enhance the collectivity stiffness of platform, it will make the structures heaver, that is to say, it can't meet the economic demand;the second way is to implement active control, however, it is difficult to be carry into execution and unable to decrease the expensive cost. The third way is to put negative isolation control in practice. For the whole, the last one is feasible and economic. This thesis research is based on the isolation technology.This article introduces the ice-induced vibration of fixation cone and ice force function. We can know that ice-induced vibration is a narrowband random course. From ice-induced function graph, so we can regard the ice force as impact load. We try to design the cone that has the function of isolated vibration by impact isolated vibration theory. From the result of simulating, the effect of reduce vibration is very evident, when the inherence frequency of cone is far away from the inherence frequency of offshore platform .Isolated vibration cone design includes stiffness design and damping design. Rubber bearing is adapt to isolated vibration of cone for its large bearing the weight of vertical and moderate horizontal stiffness .Moreover, rubber has a long time of use and high resistance of eroding.