Accession Number : AD0726372

Title :   Strength and Deformability of Rocks at Low Temperatures.

Descriptive Note : Research rept.,

Corporate Author : COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H

Personal Author(s) : Mellor,Malcolm

Report Date : MAY 1971

Pagination or Media Count : 80

Abstract : Strength tests were made on three types of rock, both 'air-dry' and water-saturated, at temperatures from +25 to -195C, and stress/strain tests were made down to -60C. Strength of air-dry specimens increased with decreasing temperature at an average rate of approximately .002/C and quasi-elastic moduli increased at comparable rates. Static fatigue mechanisms in air-dry rock were apparently influenced by temperature-modification of adsorbed water. Strength of water-saturated specimens increased dramatically as pore water froze, and continued to increase down to -120C, where compressive and tensile strengths were greater than room temperature values by factors of 5, 4 and 2 for sandstone, limestone and granite respectively. Compressive stress/strain curves for saturated rocks became steeper after freezing, and initial tangent moduli for saturated high porosity rocks increased by well over an order of magnitude. (Author)

Descriptors :   (*ROCK, COMPRESSIVE PROPERTIES), LOW TEMPERATURE, SHEAR STRESSES, ELASTIC PROPERTIES, SANDSTONE, LIMESTONE, GRANITE, TENSILE PROPERTIES, STRAIN(MECHANICS), TEST METHODS, TEMPERATURE, WATER, POROSITY, FATIGUE(MECHANICS)

Subject Categories : Geology, Geochemistry and Mineralogy

Distribution Statement : APPROVED FOR PUBLIC RELEASE