Accession Number : AD0630201

Title :   SEA ICE STRENGTH STUDIES ON MCMURDO SOUND DURING THE AUSTRAL SUMMER 1964-65.

Descriptive Note : Rept. for Oct 64-Nov 65,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CALIF

Personal Author(s) : Paige,R. A. ; Lee,C. W.

Report Date : MAR 1966

Pagination or Media Count : 27

Abstract : During the austral summer of 1964-65, a study of some of the physical properties of sea ice was made near McMurdo Station, Antarctica, where the sea ice is used extensively for aircraft operations, travel, freight hauling, and docking facilities. Tests of specimens showed that both shear and ring-tensile strengths increased almost linearly as specimen temperature decreased; the strength decreased as the ice sheet became warmer and more nearly isothermal. Average shear strength decreased from 140 psi in late October to a low of 90 psi in late January and then increased to 115 psi by 10 February just before breakup; average ring-tensile strength similarly decreased from 190 psi in mid-December to a low of 145 psi in early February, and then increased to 170 psi by 10 February. Internal deterioration and decrease in strength, thickness, salinity of brine, and temperature gradient are all related to rising temperatures and increased solar radiation during the summer. Development of a reliable method of predicting the bearing capacity of sea ice depends upon more detailed knowledge of the effects of loads, the history of the ice, danger zones and safety factors, and other features to insure safe operation on the ice. (Author)

Descriptors :   (*ICE ISLANDS, ANTARCTIC REGIONS), (*ANTARCTIC REGIONS, ICE ISLANDS), SEA WATER, ICE, MECHANICAL PROPERTIES, TRAFFICABILITY, SOLAR RADIATION, DEGRADATION

Subject Categories : Snow, Ice and Permafrost

Distribution Statement : APPROVED FOR PUBLIC RELEASE