Research progress on multi-scale damage of rock

Rock damage and rupture is a multi-scale chain damage rupture process from microscopic to mesoscopic to macroscopic. It is essential to clarify the damage characteristics of rock at different scales and establish the quantitative relationships of multi-scale damage in complex environments. In recent years, researchers have carried out a lot of research work on the multi-scale damage mechanism of rock in complex environments, and achieving certain research results. This paper systematically reviews the research progress of multi-scale damage of rock from three aspects: the characteristics of multi-scale damage of rock, identification and quantitative characterization of damage at different scales, and the quantity-response relationship of multi-scale damage. Firstly, the microscopic, mesoscopic and macroscopic damage characteristics of rock were summarized, and the multi-scale cumulative damage fracture process of rock was analyzed. Secondly, based on the characteristics of multi-scale damage of rock, the identification methods of microscopic, mesoscopic and macroscopic damage of rock and the quantitative characterization methods of damage at different scales were systematically reviewed, and the methods for determining the quantity-response relationship between microscopic, mesoscopic and macroscopic damage of rock were analyzed. Finally, the deficiencies in the research of rock multi-scale damage were analyzed from the aspects of multi-scale damage identification, quantitative characterization, and determination of quantity-response relationship. Proposing to carry out the research on rock multi-scale damage from the following aspects: developing rock micro-meso damage identification equipment highly integrated with the environment, establishing a collaborative intelligent quantitative characterization method for multi-scale damage in the three-dimensional space of rock, constructing a complete quantity-response relationship for micro-meso-macro rock damage, and enriching and innovating the theory of multi-scale rock damage.