Study On Damage Identification Of Ship-ice Impact Based On Model Test

Ship-ice impact has been the governing design scenario for the dimensioning of the bow structure for polar classed ships.To meet the requirements of ice breaking capacity and hull structural strength,rule-based design is the main procedure in the structural design of a polar ship.However,the current rule-based analysis of the ice impact load is achieved through the introduction of a uniform pressure applied to the hull surface.This uniform pressure approach does not account for the non-linear spatial and temporal variations observed in the published ice load measurements.This paper aims to investigate the non-linear variation of the ice load during ship-ice impact and study the damage behavior of the ship structure by model testing and numerical simulation.Firstly,a series of model tests were performed in the ice tank of Tianjin University to investigate the influences of several factors on the impact load,such as the testing method,the impact location,the mass of the ice floe,and the shape of the floe's edge.On the basis of a thorough understanding of the ship-ice impact process,the present study proposed five principles for the model testing of ship-ice impact,and established the standard testing method and data processing procedure.Based on the present tests,the spatial and temporal variations of the impact load were analyzed in detail.According to the derived nonlinear characteristics of the impact load,a simplified ice force function was established and used as the input of the numerical simulation.Then,the non-linear finite element analysis was used for the simulation of the structural damage under ship-ice impact load.The ship hull structure was simulated by the ANSYS software and the dynamic structural response was investigated based on the established simplified non-linear ice force function.Finally,the results were compared with the static analysis results.