Micromechanics model of ice fields-II: Monte Carlo simulation

The graph model presented in Part I of this series provides the basis for development of a computer simulation of tightly packed ice fields taken as ensembles of square-shaped ice floes with random physical properties. A program based on an alternating-direction scheme is developed to model the time evolution of a field of ice floes in a rectangular domain. The simulation of a field in an Arctic channel shows that there is a strong tendency for an earlier onset of microscale plastic flows and formation of irregular clusters of ice floes and openings in a field with spatially random properties versus a field with deterministic spatially homogeneous properties. A special study is conducted of an elastic-plastic transition in a field of 101×101 floes. The transition to macroscopically plastic flow is possible only with a percolation of inelastic regions through the entire domain of the ice field. The fact that this percolation is characterized by a noninteger fractal dimension uncovers a (possibly principal) generation mechanism of ice field morphologies, and points to scale dependence in mechanics of ice fields for certain ranges of loads.