Loads exerted by floating ice on a cylindrical structure

• Autorzy: Staroszczyk R.
• Języki publikacji: EN

Abstrakty

EN

The paper is concerned with the problem of interaction between a coherent floating ice cover and a fixed, rigid, vertically-walled circular cylinder. The ice cover, of horizontal dimensions considerably larger than the size of the structure, is assumed to be driven against the structure by wind and water current drag stresses. The floating ice cover is modelled as a plate that is subject to the action of horizontal forces and transverse bending due to the reaction of underlying water. During an interaction event, of a quasi-static character, the ice is modelled as a creeping material the behaviour of which is described by a viscous flow law with two, bulk and shear, viscosities. The viscosities change dramatically in their magnitudes during a transition from converging to diverging deformation of the material to reflect the fact that floating ice offers much less resistance to tensile rather than compressive stresses. By numerical simulations carried out by a finite difference method, the influence of the ice rheological parameters on the distribution of contact stresses at the ice - structure interface is investigated. Two types of boundary conditions at the interface, free-slip and no-slip, are considered, and their effects on the loads sustained by the structure are compared. In addition, creep buckling of the ice sheet near the structure is analysed to determine the critical time at which ice starts to fail due to exceeding its flexural strength at given loading conditions.

Słowa kluczowe

EN

floating ice; plate; rheology; creep buckling; finite difference method

• Wydawca: Institute of Hydro-Engineering of Polish Academy of Sciences
• Czasopismo: Archives of Hydro-Engineering and Environmental Mechanics
• Rocznik: 2005
• Tom: Vol. 52, nr 1
• Strony: 39--58
• Opis fizyczny: Bibliogr. 13 poz., il.

Twórcy

autor

Staroszczyk R.

• Institute of Hydro-Engineering, Polish Academy of Sciences, ul. Waryńskiego17, 71-310 Szczecin, Poland

Bibliografia

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