Quantifying Ice Pressure Conditions and Predicting the Risk of Ship Besetting

The risks of ship besetting under ice pressure are examined. Hindcasts of ice dynamics examine the conditions that led to the besetting of two vessels in the Gulf of St. Lawrence on 9 March 2005. The analysis examines the distributions of potentially significant variables such as pressure (mean normal stress), ridge thickness and strain rates. A criterion for assessing the risk of besetting was then proposed. A preliminary parametric study was also done in order to illustrate a method for predicting the risk of besetting under different ice and environmental forcing conditions.