PRELIMINARY-RESULTS FROM FATIGUE TESTS ON IN-SITU SEA-ICE BEAMS

Measurements of the fatigue characteristics of sea ice will give an in dication of its possible failure mechanisms under repeated loading suc h as occur with wave action and the operations of vehicles and aircraf t. In this paper we present the results of a series of fatigue experim ents carried out in the McMurdo Sound, Antarctica during the summer of 1992. The results presented here are in the form of a standard fatigu e curve (with zero mean stress), that is ''stress amplitude'' versus ' 'number of cycles to failure'', commonly known as an S-N curve. The '' endurance limit'', that is the stress below which the sea-ice can with stand an unlimited number of cycles, is for sea ice in situ, approxima tely half the failure stress.