Journal of Glaciology
Tensile tests have been performed onnotched and unnotched cylindrical samples of randomlyoriented polycrystalline ice of controlled grain-size (between2.2 and 7.3mm) at a loading rate of lOOPaS-l and at a temperature of -10 0c. In the notched samples, the notch-root diameter was 80% of the base diameter. Anotch-strengthening effect was observed in the large-grained ice, with fracture stresses being up to 50% higher than that for unnotched samples of the same grain-size. This notch-strengthening effect diminished as grain-size decreased, disappearing at a grain-size of "'3 mm. The notch-strengthening effect is explained in terms of the triaxial stress constraint at the notch root. This triaxialconstraint results in a change in the controlling mechanismof fracture from crack propagation in the unnotchedsamples to crack initiation in the notched samples.
Nixon, Wilfrid A. and Schulson, Erland M., "A Notch-Strengthening Effect in Fresh-Water Ice" (1990). Open Dartmouth: Faculty Open Access Articles. 2505.