抄録
The parameter m in the Ishimoto-Iida's frequency—amplitude relation is investigated on acoustic emissions occurring in granite and granodiorite specimens under uni- and tri-axial compression tests. It is found that the m-value in the case of uniaxial test decreases with an increase in axial stress, and that the m-values in the triaxial test of 200 bars of confining pressere are somewhat larger on the average than those in the former case at the same stress difference. The m-value in the latter seems to fluctuate even while the stress difference is kept nearly constant. In the case of cyclic loading of uniaxial stress on granite, the m-value on the second loading is larger than that on the first loading at almost the same stress. These characteristics suggest that the m-value does depend not only on the stress difference but also on the mode and history of deformation of rock sample.