Investigation on Acoustic Emission Kaiser Effect and Frequency Spectrum Characteristics of Rock Joints Subjected to Multilevel Cyclic Shear Loads

Figure 11

Signal distributions of tensile and shear cracks under different normal stress levels, which the ratio of the RA and the AF value is set to 1 : 10.

(a)  MPa

(b)  MPa

(c)  MPa

(d)  MPa