Overview of Recent Program on Mechanical Properties of Sea Ice

Abstract

This paper describes field and laboratory measurements of the evolving physical and mechanical properties of first-year sea ice through a growth season. The primary objectives were to (1) examine sample size effects on the in situ strength and constitutive behavior; (2) improve understanding of the interrelations between physical and mechanical properties; and (3) verify models based on small-scale isothermal behavior. Replicate sets of observations were made at a site in Elson Lagoon, near Barrow, Alaska, covering fall, midwinter and spring conditions. Each set consisted of in situ fracture, creep, creep recovery, and cyclic loading experiments and laboratory measurements of flexural strength along with a complete description of the physical properties. In situ experiments employed square double cantilever beam specimens ranging in size from 0.25 m to 30 m. Electromagnetic and acoustic emissions generated by fracturing were monitored. Small-scale isothermal laboratory experiments were performed to profile the flexural strength of the sheet. The paper details the size range and loading conditions for the in situ tests and references separate publications for more detailed accounts of the experiments.