Effects of ice layer on hydrodynamic pressure of structures

Abstract

The horizontal earthquake-induced hydrodynamic pressure acting on the surface of axisymmetric offshore and coastal structures constructed in the freeze area is explored by a special semianalytical and seminumerical approach. The seawater is considered as inviscid and compressible, and the motion of the water is limited to small amplitudes during an earthquake. The surface of the seawater is assumed to be covered by a floating broken ice layer. The numerical examples are presented to illustrate the results obtained from this method. Accuracy of numerical computation is discussed in the paper. Results are provided for the rigid structures with sloping surface and sharp corners in the condition that water surface is covered by a floating ice layer. Attention is given to the effects of the floating ice layer on vertical distribution of the hydrodynamic pressure. The influence of ice layer to the frequency response of hydrodynamic pressure is investigated. The effects of geometrical shape of the structural surface on hydrodynamic pressure and the application of the proposed method to typical offshore structures subject to base motion are also discussed.