Visiting the tunnel site.
We went to Nagano and Gunma to observe the invert construction of a tunnel. We don't post pictures of the site, but it was a very valuable experience for us to actually observe the ground where the heaving/swelling had occurred. We will continue our research to elucidate the mechanism and quantitative prediction of the heaving/swelling phenomenon, which has a wide variety of ground deformations and their causes.
The photo shows the Oiwa and Meiwa rocks.