Influence of the scale effect in testing the strength of rock samples

Aspects of the scale effect in rocks are considered within the statistical theory of strength. The results from testing the strength of rock samples of different sizes are presented. It is shown that the average tensile strength falls slightly, and its values drop substantially when the sizes of samples increase. A procedure is developed and tests are performed with the compression of granite samples ~6 mm in diameter. The possibility of using this procedure to identify the strength properties of rocks with allowance for the scale effect is discussed.