Acoustic Emission and Ultrasonic Characteristics in the Failure Process of Cemented Waste Concrete-Coal Gangue Backfilling (CWCGB) under Uniaxial Loading

Figure 3

Stress–strain–ultrasonic–AE testing device diagram. 1, insulation pad; 2, ultrasonic probe; 3, specimen 4, acoustic emission probe; 5, acoustic emission detector; 6, ultrasonoscope; 7, stress control system; ultrasonic data acquisition system; stress-strain data acquisition system; AE data acquisition system.