Size effect in penetration of sea ice plate with part-through cracks. II: Results

After development of the theory in the part I paper, systems of up to 300 nonlinear equations are solved in this paper by the Levenberg-Marquardt optimization algorithm. The maximum load is reached when the circumferential cracks begin to form. Numerical calculations show a typical quasi brittle size effect such that the plot of log σ_N versus log h (where α_N = nominal stress at maximum load and h = plate thickness) is a descending curve whose slope is negligible only for h < 0.2 m and then gets gradually steeper, asymptotically approaching -1/2. The calculated size effect agrees with the existing test data, and contradicts previous plasticity solutions.