抄録
The purpose of this study was to clarify the disagreement of the classifications of ground from preliminary geological investigation stage and that from construction stage. This study was concentrated on 1) was the ground evaluation correctly did, and 2) was the investigation quantity reasonable, based on the results of re-investigation of three existing tunnels.
To increase the objectivity of the results, the investigations were down by several geologicalengineers based on the requirements close to preliminary geological investigation on the same tunnel. Asa result, it was found that for different geographical and geological conditions, different conclusions were obtained.
