M. Johnston

Ice loads on the Molikpaq in the Canadian Beaufort Sea

The Molikpaq is a steel caisson structure that was used in the 1980s in the Canadian Beaufort Sea for exploration drilling of oil and gas. It was very extensively instrumented. Part of the instrumentation was designed to measure the ice loads. This paper presents an overview discussion of the characteristics and instrumentation of the Molikpaq. It presents detailed information on 188 ice loading events from both first-year and multi-year ice for different ice macrostructures including level ice, ridges, hummock ice and isolated floes. Investigation of the ice loads has shown that the Line Load (global load per unit length of the structure) increases with increasing ice thickness. The analysis of the ice loads in terms of the failure mode of the ice provides additional insight and explains some of the scatter in the ice load data.

Using Motan to Measure Global Accelerations of the CCGS TERRY FOX During Bergy Bit Trials

The whole-ship motions of the CCGS TERRY FOX were measured for more than 150 controlled impacts with small pieces of glacial ice, or bergy bits. The impacts were conducted at speeds up to 14 kt. This paper uses global ship accelerations measured during three different impact events to demonstrate proof of concept for an inertial measurement system called MOTAN.Copyright