Determining rock fracture toughness Mode-I using a pulsed laser scanning during the crack propagation

The investigation of the rock massifs' cracking is a crucial step in characterizing rocks since it greatly affects their mechanical behavior. In this study, large rock core samples (70 mm) were subjected to temperatures as high as 750°C and pressures as high as 50 MPa, and a novel ultrafast time-resolution technique on the basis of a pulsed laser was used to examine the mode-I crack propagation properties and fracture toughness measurements. The research examines metric properties, including roughness and averages crack-to-crack lengths, as well as the direction and angle at which fractures collapse. Single-edge specimens obtained using the 3D Laser Sintering methods were used in this case for the experimental testing. The mode-I fracture toughness (Formula presented.)) was calculated through asymmetric and symmetric four-point bending tests. In order to gain the 3D coordinates of the important reference points in a rock face, lines of sight must be mathematically crossed by capturing photos from at least two distinct angles. The complete rock surface is then produced using automatic 3D laser scanning equipment to create the 3D coordinates. The Mode-I fracture of the samples was discovered to consist of repetitive crack initiation, and arrest based on the full-automatic technique.