Influence of loading rate on the Kaiser effect for different lithological rocks

Two-cyclic loading tests with the rate different from one to the other one were conducted on three different lithological rocks to reveal the influence of loading rate on the Kaiser effect for rock,combined with acoustic emission technology. Kaiser effect fails as the experienced load exceeds crack damage stress. Instead,Felicity effect replaces. Felicity ratio could be used as a quantitative measure of the quality of rocks. FR of stress,together with other mechani- cal parameters,increases with increasing loading rate. It is found that the dependency of the Kaiser effect on loading rate should be small for brittle and hard rock,but pronounced for ductile,plastic and soft rock. The difference in exam- ining Kaiser effect between rock types strongly depends on the variation in mineral composition and microstructure,that is,the effect is pronounced for a ductile rock and insignificant for a brittle rock.