Fracture of a ridged multi-year Arctic sea ice floe

As part of the 1994 Sea Ice Mechanics Initiative experimental program, fracture experiments were carried out on an 80 m diameter ridged multi-year (MY) ice floe in the Beaufort Sea. An edge cracked, quasi-circular ridged floe was subjected to both cyclic and ramp loading sequences using a steel flat jack. Load, crack opening displacement, acoustical and seismic measurements were made during the experiments. The objective was to gain further insight into the fracture and constitutive properties of MY sea ice. Accurate predictions of the strength of MY sea ice and the forces developed during interactions between MY sea ice and floating or fixed structures are sought. Such interactions include MY ice floe collisions with offshore structures and ships. The fracture resistance of MY ice is determined to be within the range 23 < Gc < 47 J/m2 for a 80 m diameter ridged MY floe. This fracture energy is similar to values obtained for the fracture of FY sea ice both in the Arctic and the Antarctic.

► First in situ fracture of a MY floe.
► First in situ fracture of a ridged MY floe.
► Combined mechanical and acoustic measurements.
► First estimate of full-thickness fracture energy of a MY floe.