A sudden drop of fractal dimension: a likely precursor of catastrophic failure in disordered media

The variation of fractal dimension and entropy during a damage evolution process, especially approaching critical failure, is investigated. The results show that, as damage evolves, the fractal dimension and entropy of the spatial distribution of microcracks/voids decrease. A sudden drop of fractal dimension can be viewed as a quantitative indicator of damage localization or a likely precursor of an impending catastrophic failure. Using mining-induced rock bursts as an example, the complexity and difficulties of prediction are discussed.