Abstract Experiments on acoustic emission(AE) characteristics in two frequency channels of the full failure processes in granite specimens under the different confining pressures are carried out through the load test in laboratory. The granite mechanical properties and AE characteristics in low and high frequencies are obtained. The relationship of AE ringing counts,AE accumulative energy,stress and time are analyzed. The distributions of AE signal peak frequencies before the main fracture of the granite are study in detailed. The results show that the AE basic characteristics in low and high frequencies are develop similarly during the granite failure. And they well match with the mechanical properties. The main difference between the AE basic characteristics in low and high frequency channels is the numerical value. In AE spectrum signatures side,the feature of AE peak frequency just before the rock main crack is the number of main frequency ranges increase. It shows that the peak frequencies disperse from one or two frequency ranges(40–50 kHz and 150–170 kHz) to five different ranges(25–30 kHz、40–50 kHz、60–70 kHz、90–100 kHz and 150–160 kHz).
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