ABSTRACT
This paper is a case history of the Otsu Diversion Channel Project, i.e. an underground river excavated with shield tunnelling method. The tunnel is crossing under servicing Shinkan-sen track and is required not to disturb any train operation during whole construction period. To achieve the safety of the train operations, precise and frequent ground measurement and prediction with numerical analysis were carried out. In order to make sure a safe construction of the crossing section, pre-measurement sections were set and precisely monitored for ground movements. The comparison between measured results and back analysis is also discussed in the paper.
