Thickness-independent fracture in columnar freshwater ice: An experimental study

Experiments on columnar freshwater ice indicated that there is no detected effect of the ice thickness on the fracture behavior of columnar freshwater S2 ice. The influence of thickness was studied using large laboratory -grown samples. Two series of Mode I fracture tests were carried out using deeply edge -cracked 3 -by -6 -metre rectangular plates loaded monotonically at 1...100 mu m/s. The ice was warm (above -0.5 C-degrees), and the ice thickness varied in the range 10-40 cm. This paper analyzes the second series of tests and compares the results with the first series tests; the analysis of the latter was published in Gharamti et al. (2021) [2,3,4]. The viscoelastic fictitious crack model (VFCM) was applied to analyze the data and calculate the crack profile, fracture energy and the process zone size. The thickness affected only and linearly the values of the measured loads with no influence on the fracture properties: the apparent fracture toughness, fracture energy, crack opening displacements, notch sensitivity and process zone size.