Local Design Pressures for Structures in Ice: Analysis of Full-Scale Data Available to Purchase

The design of structures for ice conditions requires knowledge of local ice pressures to allow for appropriate levels of structural strengthening. Full-scale field data are key to enhancing our understanding and modeling of ice behavior. Data collected during icebreaker ramming events represent an important source of information for use in the evaluation and validation of design methodologies. This paper examines several ship-ice interaction datasets using the ‘event-maximum’ method of local pressure analysis developed by Jordaan and co-workers [1]. In this method, the local pressure is obtained from a normalized curve which contains two parameters, α and x₀. Local pressure analysis results for data from the USCGS Polar Sea, CCGS Terry Fox, CCGS Louis St. Laurent, and Swedish Icebreaker Oden are presented. For all data considered the calculated values of α fall below the design curve. A discussion of panel exposure, event duration and the effect of these factors on x₀ is given. New design curves are presented. A comparison of results with those obtained using an alternative approach, the up-crossing rate method, is presented in a companion paper [2].