Mehdi and his team conducted a series of Brazilian tests on brittle rocks, including granite, basalt and monzonite. They loaded the specimens under a constant displacement rate until failure occurred, usually within 1 to 2 minutes. They recorded the fracturing process using a Phantom v2011 ultra-high-speed camera system running at 130,000 frames per second (fps) at a resolution of 384 x 288 pixels. As expected, the high-speed footage revealed that additional secondary cracking at the loading points always accompanied tensile failure.

Geomechanics Research