Ice Stimulated Vertical Structure Of Steady-state Vibration

Full scale tests conducted at the Bohai sea LiaoDong Bay to research the interaction between moving ice sheet and structure have revealed four regimes of vibration modes, in which the steady state vibration is the most serious one. In order to discuss profoundly, main opinions on this topic is listed and their rationality and applicability is discussed, especially on whether it can be used to explain the lock-in phenomenon. After understanding the literature background of this topic, the research expands in this paper.As the steady state vibration is qualified as a self excited vibration induced by the nonlinear force of the sea ice, the study can be divided into two parts. First of all, in order to obtain the nonlinear ice force, the first part concentrates on the research for the physical property of ice. especially on the ductile to brittle transition mechanism. After deep comprehensive of the ice crushing mechanism, and consulting Sinha's incremental model, this paper gives out a simplified constitutive equation as an application of the statistic damage model. Secondly, this paper develops a coupled model between ice and structure after knowing the constitutive behavior of sea ice; focus on the effects of wing cracks to the coupled vibration. And the stability of steady state vibration is also discussed qualitatively.This paper analysis the reason of the steady state vibration, gives out the theoretical dependence to the engineering design.