Finite element modelling of damage process in ice-structure interaction

Abstract

Two field programs were carried out on the Hobson's Choice Ice Island in April, 1989 and May, 1990 using different sizes of spherical and flat indenters. Several cores of multiyear field ice were recovered from the ice island and transported to Memorial University to conduct compressive tests in the laboratory. Both constant strain-rate tests and constant stress tests were performed with uniaxial stress to investigate the deformation of multiyear ice and calibrate the material constants for theoretical modelling. -- The spherical indentation tests are modelled using an axisymmetrical finite element model. The ice damage process is related to the growing network of micro-cracks and the ice creep process is also enhanced by the existence of cracks. The damage model is developed in FORTRAN code and implemented as a user subroutine in the ABAQUS finite element analysis program. The analysis results show that most of the ice damage is close to the contact surface, and that the maximum damage occurs at the edge of the interface where shear stress is concentrated. This is in agreement with the test results. The model also provides good results on the total load versus time history.