ABSTRACT
In order to study the effect of defects on rock dynamic mechanical properties and crack propagation behavior, impact compressive tests were performed by using a modified split-Hopkinson pressure bar device on marble specimens with different types of artificial defects, including single-flawed (inside the specimen) prismatic specimens with different lengths and angles, double-flawed (at the end surface) cylindrical specimens with different flaw angles and prismatic specimens with a single circular or elliptical hole. The results indicate that the dynamic compressive strength and strain of marble is obviously influenced by the flaw geometry. White patches usually appear before the development of macrocracks and shear cracks initiate at or near the flaw tips earlier than tensile cracks. The presence of artificial defects may change the failure mode from splitting-dominated for intact specimens to shear-dominated or combined shear and tensile failure for flawed specimens under dynamic loading.
