Test Method Title
Standard Test Method for Unconfined Compressive Strength of Intact Rock Core Specimens **ASTM has discontinued this method, the industry-accepted standard test method is now ASTM D7012C
Reference Number
ASTM D2938
Material
Rock
Test Property
Unconfined Compressive Strength
Description of Test
A rock core sample is cut to length and the ends are machined flat. The specimen is placed in a loading frame and, if required, heated to the desired test temperature. Axial load is continuously increased on the specimen until peak load and failure are obtained. Unconfined compressive strength of rock is used in many design formulas and is sometimes used as an index property to select the appropriate excavation technique.
Number of Test Specimens
Enough samples to represent a valid average of the type of rock under consideration
Test Specimen Size
Right circular cylinder, with diameter of at least 1 7/8 in and a length to diameter ratio of 2 to 2.5:1
Keywords
Compression testing, compressive strength, loading tests, rock