FATIGUE OF FRESH-WATER ICE

Experiments were performed to observe cyclic crack growth in S2 column ar freshwater ice and granular freshwater ice with randomly oriented g rains. The ice was loaded in four-point bending such that the crack op ened in a mode-I manner. A traveling microscope was used to measure su rface crack growth and a low-powered laser was used to map crack growt h along the entire crack front. Results of crack growth measurements t ogether with micrographs of failure surfaces support a qualitative des cription of the failure mechanisms operable near the crack tip during cyclic loading. (C) 1997 Elsevier Science B.V.