Abstract
The moment tensor of acoustic emission (AE) is physically derived from a crack-motion vector. Thus, a relation between crack orientation determined from the moment tensor and the stress intensity factors in the linear elastic fracture mechanics (LEFM) is investigated. In bending tests of notched beams, the normalized stress intensity factors K I and K II are determined from the moment tensors of AE events. A criterion applied to crack classification of AE source is confirmed to be reasonable from the relation between the stress intensity factors and the shear ratio. Variations of K I and K II under crack extension are obtained. It is found that results are comparable to analytical results by BEM analysis.
