Investigation of the fracture mechanism of level ice with extended finite element method

Abstract

This paper investigates the fracture mechanism of level ice based on the extended finite element method by simulating collision scenarios between ice and a rigid ship structure. It is found the collision velocity and structure inclination affect the fracture mode through changing the deformation and stress distribution of the level ice. The overall response of the level ice is simulated with the transversely isotropic material model and cohesive zone model. The numerical model is verified with the data from a field test, which shows that the obtained ice load and size of the broken ices from numerical method are well consistent with the tested data. Two fracture modes of the level ice, bending and splitting, appear in the simulated cases. The bending crack is found to emerge from the top surface of the level ice and expand along the circumferential direction, and the splitting crack initiates at the bottom edge of the level ice and expands along the radial direction. Deformation and multiple stresses of level ice are analyzed, showing that the initial cracks for both fracture modes are related to the local tensile failure, and the location of the maximum tensile hydrostatic stress always coincides with the initial crack.