Abstract
This study presents a novel approach for simulating the concurrent flexural and crushing failure of level ice when interacting with sloping structures. The mechanical behaviour of ice is simulated by a nonlinear viscoelastic constitutive model with progressive damage, accounting for microstructural evolution and phase transitions in polycrystalline ice under compression. The constitutive model, scripted in Fortran, has been validated against laboratory-scale physical tests.
To simulate the flexural failure of ice, the ice domain is first discretized with hexahedral finite elements that do not share nodes with their neighbouring counterparts in the in-plane directions. Then, a cohesive contact model with a traction-separation law and damage evolution is implemented to define cohesive interaction behaviour at the vertical interface of adjacent elements. This model, based on a Discrete Finite Element Method (DFEM), allows for the computation of multiple crack initiations and propagations, effectively simulating ice fragmentation into rubble. Therefore, the proposed ice model eliminates the need for predetermining ice breaking length, a notable limitation in prior studies that utilized the cohesive zone method.
To validate the ice model, a numerical model of an ice-breaking cone mounted on a jacket structure in the Bohai Sea interacting with drifting level ice is developed. Good agreement between the numerical results and the field measurements is achieved, which demonstrates the effectiveness of the proposed ice model.
