Applicability for the estimation of a rock strength by Schmidt hammer based on in-situ measurement

Kuji, Masayoshi*; Asai, Hideaki; Matsui, Hiroya 

Two deep shafts (the Main Shaft and the Ventilation Shaft) at The Mizunami Underground Research Laboratory (MIU) is currently being constructed by Japan Atomic Energy Agency (JAEA). To estimate the rock mass quality and UCS on shaft wall, existent rock mass classification methods (CRIEPI, RMR and New-JH) and in-situ Schmidt hammer tests were applied in rock. In this report, applicability for the estimation of rock strength by Schmidt hammer is discussed based on in-situ measurement data.