SIMULATION OF THE TEMPERATURE AND GRAIN SIZE DEPENDENT UNIAXIAL COMPRESSIVE STRENGTH USING 3D WING CRACK MODEL

摘要

A number of measurements of uniaxial compressive strength of sea ice and fresh water ice have shown that the strength increases with decreasing temperature. Also the kinetic ice-ice friction increases with decreasing temperature. During compression number of micro-cracks initiate and propagate. Frictional sliding of these cracks play significant role in the deformation process; increase of the strength is a result from the increased friction. In this paper the effect of temperature dependent kinetic friction and the effect of grain diameter on the compressive strength are studied using the new 3D wing crack model. The two dimensional kinematic sliding crack model has been extended into three dimensions to describe the inelastic deformation mechanism. Interaction of cracks and the inhomogeneity of material are considered in the approach. The model has been implemented into finite element software as a user subroutine. The numerical simulations revealed good results compared to experimental results found in the literature. The proposed approach was found to be capable to simulate the increase of the compressive strength with decreasing temperature. In addition the model was found to be capable to simulate the increasing trend of strength as a function of decreasing grain diameter.