Effect of growth rings on acoustic emission characteristic signals of southern yellow pine wood cracked in mode I

The effects of growth rings in terms of crack tip locations (at earlywood, early-latewood interface, and latewood) on the acoustic emission (AE) characteristic signals of southern yellow pine (SYP) wood subjected to a compact tension load in its radial-longitudinal crack propagation system were investigated. Experimental results indicated that crack tip locations had significant effects on AE characteristic signals such as counts and energy but not amplitude. All investigated AE characteristic signals vs time curves can be characterized as three distinct stages of initiation, acceleration, and failing. In the initiation stage, the cumulative AE counts at earlywood were significantly greater than those of early-latewood interface and latewood. In the acceleration stage of a cumulative AE counts vs time curve, the counts rate and mean maximum counts at earlywood were significantly greater than those at early-latewood interface, followed by latewood, correspondingly. These significantly different patterns in AE characteristic signals could be used in detecting cracks occurring in a wooden structure.

Automated summary

This study investigates the effects of growth rings on acoustic emission (AE) characteristic signals in southern yellow pine (SYP) wood. Results show that crack tip locations significantly affect AE counts and energy, but not amplitude. AE counts and energy are higher in earlywood compared to the early-latewood interface and latewood. These distinct AE characteristic signals can be used for crack detection in wooden structures.