On modeling cohesive ridge keel punch through tests with a combined finite-discrete element method

This paper introduces a technique for modeling partly consolidated ice rubble using a two-dimensional combined finite-discrete element method and an application of the technique on ice rubble punch through experiments. In the technique, each ice block within the rubble, the contact forces between the blocks, the block deformation, and the rubble freeze bonds are modelled. Simulations with various freeze bond strengths and block to block friction coefficients were performed. As a main simulation result, the close relationship between rubble deformation patterns and load records is demonstrated in detail. It is shown that the buoyant load component due to the rubble becoming detached from the surrounding rubble field and displaced during an experiment is of crucial importance when interpreting punch through experiment results. The consequences of simulation results on ice rubble material modeling are discussed.

► Partly consolidated rubble was modeled using combined FEM-DEM ► Technique for modeling freeze bonds using combined FEM-DEM is presented ► Punch through experiment results strongly depend on rubble failure patterns ► Incorrect assessment of failure process leads to errors in interpretation of results ► Change in rubble geometry in a test could be misinterpreted as material softening