Acoustic emission character of loaded rock under load-unload disturbance

Based on load-unload experiment, the acoustic emission (AE) character of rock samples under load-unload disturbance was studied and tested under different stress levels. The results show that under a low stress level, there are several discrete AE signals when the rock sample is loaded, and almost no AE signals during unloading; under a high stress level, AE is active relatively under load disturbance, and there are obvious AE signals even during unloading. AE signals under different stress levels and stress states refleet different constitutive properties of rock materials. This characteristic must be considered in the stability testing and evaluation of underground engineering in-situ rock mass.