Analysis of acoustic emission parameters and energy dissipation characteristics and damage evolution of bedding rock failure process under uniaxial compression

Bedding structures are widespread and has a tremendous threat to stability of mine pillars. In this paper,the uniaxial compression tests (UCT) and CT scanning tests have been carried out on bedding rock and homogeneous massive rock. Through the analysis of acoustic emission ( AE) characteristics,energy dissipation and transfer law in the process of the damage evolution of rock specimens,the damage model based on AE parameters and energy dissi- pation has been established. The results show:firstly,the mainly failure mode of rock specimens with bedding structure is inclined plane shear failure,with the obvious shear fracture zone. But homogeneous massive specimens are mainly featured by tensile failure and formed longitudinal fracture face,with brittle failure characteristics. And the weak struc- ture of the bedding will weaken the bearing capacity of the pillar to a certain extent. Secondly,the failure of bedding rock occurs mainly in the plastic strain stage,it corresponds to AE violent period. Its axial loads are in the 60% σc -σc range and its failure time is within the range from the 63% tc to tc . The period for failure prediction of homogeneous massive rock should focus on before and after the yield point. The trend of dissipation of the strain in this interval is slowly decreasing (before the yield point c) → rising (after the yield point c) → sudden increase (failure point d). Thirdly,the damage model based on parameters of AE and energy dissipation is verified through real data computation and experiments,which shows that the average deviation rate of bedding rock is 8. 2% and 9. 5% and to homogeneous massive rock is 18. 4% and 19. 3% .