SOURCE WAVE ANALYSIS OF LARGE AMPLITUDE ACOUSTIC EMISSION IN THE BREAKING OF GLUE LINES

Abstract

The acoustic emission (AE) source wave analysis was applied to the breaking of the wood with a glue line. Tapered double-cantilever beams were used as the test specimens. In the case of solid wood, the value of critical energy release rate obtained from the released energy in the source wave analysis was in good agreement with that from the fracture load. In the breaking of the glue lines, the ratio of the critical energy release rate from the fracture load to the released energy in the source wave analysis decreased with decreasing the wood failure. On the other hand, the decrease of the ratio can be attributed to the decrease of the fracture strain of glue lines. The above results show that the fracture pattern of the breaking of the glue lines is the interfacial failure in the category for the glue line failure.