Study on the Characteristics of Acoustic Emission Quiet Period in Rocks with Different Elastic Modulus

To study the characteristics of quiet period acoustic emission (AE) during rock failure process, models with an abnormal elastic modulus were established based on PFC2D. The calibration mesoscopic parameters was performed by macroscopic mechanical granite samples obtained in uniaxial compression tests. An area 2 × 100 mm2 set at center model and had two to six times normal area. evolution law cracks AE analyzed detail. main conclusions are as follows: (1) axial stress rises maximum value before occurrence fracture; period, increased 2%–5%, then decreases rapidly after period. (2) As increases, interval time is prolonged one five times. Furthermore, many occurred mainly area, a few generated Cracks focus propagate beyond (3) Z used indicator significance it changes without minimum 1.1, three reaches 6.08, modulus. distribution different important factor concerned