AE technique is proved a efficient tool for real-time monitoring of the crack initiation and
propagation during rock failure process under uniaxial compression condition. In this paper, An AE
system was employed to investigate the crack propagation and failure modes of three groups of
granite specimens (80mm×100mm×170mm) with the same pre-existing crack. The AE sensors can be
surface mounted. By using a Geiger location algorithm, AE event location can be determined by
time-of-arrival times. The propagation velocities of p-wave or s-wave of granite samples were
measured. Experiments on pre-existing crack propagation of granite samples were carried out on the
press machine. From the testing result, failure mode of three kinds of granite samples was mainly
shear failure, while the secondary crack propagated slowly and could not influence the failure mode of
granite sample. By surveying the relation of accumulative AE events and stress-strain curve, AE
activity represents different characters with stress-strain changing during the total loading process,
microcracking contributing to fracture propagation with strain corrosion. AE location result reflected
crack initiation and propagation, which is of great importance in studying rock instability and
predicting rock failure mode.
Fatigue Crack Initiation and Propagation Behavior of a Nickel Alloy ; A Study of Structural Integrity Assessment Method Based on Polycrystalline FE Analysis
