Inference of in-situ stress by Blasthole Damage Method (BDM) at Mizunami URL and its comparison with other direct and indirect methods

Aydan, .*; Sato, Toshinori  ; Hikima, Ryoichi*; Tanno, Takeo

There are various indirect stress inference techniques utilizing borehole breakouts, fault striations and earthquake focal mechanism solutions. Recently, a new stress inference technique utilizing damage zone around blastholes has been proposed and applied to several sites in Japan and Turkey. This method has been utilized in Mizunami Underground Research Laboratory (MIU) used to infer the stress state from the damage around blasted holes. The inferences are compared with in-situ stress measurements and also inferences from other indirect stress inference techniques such as fault striation, earthquake focal mechanism solutions. In this article the studies undertaken so far have been presented and the possibility of the BHD method as an effective indirect tool for actual engineering applications has been discussed when extensive network of underground openings have to be excavated.