Research on damage constitutive model and evolution equation of coal under uniaxial compression

Based on the CT real-time testing of coal microscopic damage propagation, the comparison of damage variable between CT scanning and Bellonoi equation, Lemaitre equation in the process of uniaxial damage spread was obtained which solves successfully damage discriminating 'scale' problem, and the results is more reasonable than Bellonoi equation and Lemaitre equation. In order to describe logically its behaviors and evolution, its constitutive model and evolvement function under uniaxial compression were carried through separately in pre-linearity phase, start and development. phase, speedup phase, which it is important to guide engineering.