Experimental studies on the effect of stress history on acoustic emission activity ― a possibility for estimation of rock stress

In the present study, we examined the stress history effect of the AE activity under repeated loading and clarified the reason why the new method of repeated loading has wide applicability. Next we studied the recovery of the Kaiser effect by experiments with long time intervals up to three years. Although some investigators reported different results on the time dependence of the Kaiser effect, it is shown that the apparent inconsistent results are due to differences in the previously applied stress level