Damage and fracture behavior and spatio-temporal evolution of acoustic emission of sandstone before and after laser radiation

• Published in: Journal of Central South University Vol. 31; no. 9; pp. 3264 - 3280
• Main Authors: Gao, Ming-zhong, Liu, Jun-jun, Li, Chun-xiang, Yang, Ben-gao, Li, Fei, Zhou, Xue-min, Yang, Lei, Yang, Zun-dong, Xie, Jing
• Format: Journal Article
• Language: English
• Published: Changsha Central South University 01.09.2024; Springer Nature B.V
• Subjects: Acoustic emission; Compressive strength; Elastic properties; Energy distribution; Engineering; Failure modes; Laser damage; Lasers; Mechanical properties; Metallic Materials; Modulus of elasticity; Poisson's ratio; Radiation; Radiation damage; Sandstone; Storage capacity; 力学损伤; 激光破岩; 高效钻进; strength reduction; mechanical damage; laser rock breaking; 强度弱化; 声发射; acoustic emission; efficient drilling
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-024-5711-7

Laser technology holds significant promise for enhancing rock-breaking efficiency. Experimental investigations were carried out on sandstone subjected to laser radiation, aiming to elucidate its response mechanism to such radiation. The uniaxial compressive strength of sandstone notably decreases by 22.1%–54.7% following exposure to a 750 W laser for 30 s, indicating a substantial weakening effect. Furthermore, the elastic modulus and Poisson ratio of sandstone exhibit an average decrease of 33.7% and 25.9%, respectively. Simultaneously, laser radiation reduces the brittleness of sandstone, increases the dissipated energy proportion, and shifts the failure mode from tensile to tension-shear composite failure. Following laser radiation, both the number and energy of acoustic emission events in the sandstone register a substantial increase, with a more dispersed distribution of these events. In summary, laser radiation induces notable damage to the mechanical properties of sandstone, leading to a substantial decrease in elastic energy storage capacity. Laser rock breaking technology is expected to be applied in hard rock breaking engineering to significantly reduce the difficulty of rock breaking and improve rock breaking efficiency.