Renovation construction work making full use most advanced technologies.

This dam was constructed with the most advanced technologies at the time of its construction in 1966, such as the adoption of bedrock PS anchors. After 50 years, as a result of investigating the soundness of the existing anchors, it was decided to install new replacement anchors.

In this reinforcement work, I am mainly in charge of quality control and safety control of the anchor work. Since the bedrock PS anchor, which is driven into the bedrock and hardened with cement milk is an irreversible task, the safety from assembly to the installation of the anchor, quality of the tendon that bundles the steel wire, control of hole curvature during drilling, quality of the cement milk to be injected, etc. are carefully and strictly controlled.
One of the difficulties in the Kawamata Dam reinforcement work was the working platform. Because it was extremely difficult to install a gantry covering a steep bedrock, after trial and error, we installed it so that we stick it on the steep bedrock. Since the working platform is narrow and work is carried out at high altitudes, we always pay attention to safety.

I have been involved in the construction of passageways for subway stations, and the Kawamata Dam was my first dam site. There was a lot to learn from the basics, such as calculations related to management and construction specific to the arch dam. The renovation works of this time just adding more anchors look like simple at a glimpse, though special and advanced technologies are used, such as the most extensive scale anchor in Japan, the "two-stage tensioning" construction method that reinforces multiple points depending on the bedrock conditions and scaffolding design for steep slopes. I would like to continue to study so that I can utilize the knowledge and technology I have acquired here in the future of dam construction and renewal work.