Numerical simulation of local ice loads in uniform and randomly varying ice conditions

The ice loading process has a clear stochastic nature due to variations in the ice conditions and in the icebreaking processes of ships. The statistical characteristics of local ice loads are typically studied on the basis of field measurements. In this paper, a numerical method was applied to simulate a ship moving forward in either uniform or randomly varying ice conditions, where the thickness and strength properties of the ice encountered by the ship were assumed to be constant or randomly generated using the Monte Carlo method. The purpose of this simulation is to show the origin of the statistical variation in ice loading, which is difficult to identify in field measurements. To validate the numerical results, an icebreaking tanker, MT Uikku, was then modeled in a simulation program, the ice loading process was stochastically reproduced and the calculated amplitude values of the ice-induced frame loads were compared with the field measurements.