Experimental Study on the Spatial–Temporal Failure Characteristics of Red Sandstone with a Cemented Structural Surface under Compression
Ansen Gao, Chengzhi Qi, Renliang Shan, Chunlai Wang
Abstract
/s) at elastic deformation stage, which was termed as the "quiet period". The acoustic emission ring counts initially exhibited an obvious jump increase phenomenon at the forthcoming brittle failure stage before stress curve produced an obvious turning point, and then, it entered the "relatively quiet period". Based on the acoustic emission index (rise angle and average frequency), at the initial destruction stage of rocks, the types of internal fractures were simple and clearly (tensile cracks or shear cracks), and the fracture location was also relatively scattered inside specimens. Subsequently, the internal fracture developed into mixed tensile and shear cracks, and then, the fracture location exhibited a progressive evolution trend in the vertical space of specimens.