Study on mechanical and fracture characteristics of rock-like specimens with rough non-persistent joints by YADE DEM simulation

Abstract

Rough non-persistent joints exist widely in natural rock mass. The roughness of joints influences its mechanical and fracture characteristics. However, the research on rough non-persistent jointed rock mass is inadequate. To investigate the effects of joint angle, rock bridge angle and roughness of rough non-persistent joints, the rough non-persistent joints were truncated and their JRC was calibrated based on the Barton typical roughness profiles. A series of DEM numerical uniaxial compression tests were conducted based on the laboratory tests of rock-like specimens with 3D printed non-persistent joints. By the investigation of mechanical behaviour, crack coalescence types, crack evolution law, fracture modes presented by the strain field, and micro-fracture mechanism revealed by the displacement vectors, it was verified that YADE is suitable to simulate the fracture of rough non-persistent jointed specimens; the six types of coalescence of rough non-persistent joints were concluded, and the relation between micro-crack and macro-fracture was established by the four types of micro-cracks causing macro-fractures.