ABSTRACT
Acoustic emission (AE) during triaxial compression tests on intact and jointed granite samples was investigated. Artificial rough and smooth joints were tested with confinement pressures from 0 to 80 MPa. The smooth joints were obtained by sawing and rough joints by shear rupture during triaxial compression tests. For the different stages of the sample mechanical behaviour, the following characteristics where analysed: AE count rate, events size distribution and spectral contents corrected for the apparatus response. Our results suggest that AE analysis allows to distinguish different mechanical behaviour: pre-peak, post-peak, shearing on rough or smooth macroscopic surfaces, stick-slip. Moreover the influence of roughness and confining pressure on the b-value is shown.
