Laboratory Validation Test of Dry-Fracture Method by Re-Boring

Takebe, Akimitsu*; Higashihara, Masami*; Takami, Akira*

One of purposes in the Inland Underground Structure Frontier Investigation is the development of the dry-fracture method to get basic data on in-situ stress states around an active fault. In previous experiments using concrete specimen and steel pipe, the dry-fracture method was determined to be reasonable. This report describes the laboratory validation test of dry-fracture method by re-boring in the difficult case to maintain the naked borehole in the bad ground situation.