18th International Conference on Offshore Mechanics and Arctic Engineering, 11-16 July 1999, St. John's, Newfoundland
ice; sea ice; Tuktoyaktuk; INSROP; hull load
As part of an INSROP project, Large Scale Hull Loading of First-Year Sea Ice, a series of tests in first-year brackish sea ice were carried out at Tuktoyaktuk in the Canadian Arctic to simulate ice loading on a ship hull. Loading was generated by hydraulic actuators impressing a rigid indentor against an ice edge. A finite element analysis of the test geometry was carried out to assess the deformation ands stress distributions in the ice edge for cases with both undamaged and varying degrees of damage. The calculated and measure stiffness of the ice edge agreed for a realistic selection of elastic modulus of the parent ice and damaged ice. The field results did not show conclusively and influence of damage on the failure strength of the ice. Review of these results and those of other field tests, including Phase 1 tests, showed that the nature of the ice loading, depending on whether it was uniform pressure or uniform deformation, significantly affected the results. Failure stress for uniform pressure tests did not have ant dependence on area or aspect ratio. The measured filed results gave average ice pressure less than those recommended by the Arctic Pollution Prevention Regulations. Crack formation and movement were studied using high speed video, and the velocity of the cracks was found to be of the order of 10 m/s.