Understanding Acoustic Emission Testing- Reading 1 Part B-A

Perhaps the most extensive series of tests on HAC, carried out at the Fulmer
Research Institute in the U.K., was reported by Williams. Apart from
observing that the Kaiser effect existed up to the point at which the beams
cracked, some tentative suggestions were made for monitoring HAC beams
with acoustic emissions:
1. If, on loading a beam, no acoustic emission is noted, then the applied load
is still less than about 60% of the ultimate load; if acoustic emission occurs,
then this percentage of the ultimate load has been exceeded.
If, upon unloading such a beam, further acoustic emission activity is recorded,
then the beam is cracked. The amount of acoustic emission during this
unloading could indicate the degree to which the cracking load had been
exceeded.
Charlie Chong/ Fion Zhang