Determination of the Dynamic Propagation Toughness of Marble Based on a Fractal Propagation Model and an Experimental-Numerical-Analytical Method

摘要

Precracked chevron-notched Brazilian disc specimens were impacted by a split Hopkinson pressure bar to determine the dynamic propagation toughness of marble. The dynamic expansion process of the crack was measured by a crack propagation gauge glued ahead of the specimen's crack tip. A fractal crack propagation model was introduced to modify the universal function, and the dynamic propagation toughness of marble was calculated using an experimental-numerical-analytical method. The results show that, when the crack speed is in the range from 0.42 to 0.54 C-R, both the fractal dimension and the dynamic propagation toughness increase with the crack propagation speed and with an approximately linear relationship.