Acoustoelastic Determination of Forces on a Crack in Mixed-Mode Loading

A technique previously presented [1] for the nondestructive evaluation of the J integral in cracked samples from ultrasonic measurements of stress, and successfully tested on specimens under mode I loading, is extended here to mixed-mode loading. Experimental results are presented for both the J and L integrals in a specimen with a slanted central crack loaded in tension, which agree well with theoretical values.