2016 Volume 15 Issue 4 Pages 151-159
Immediately after the Great East Japan Earthquake, an embankment was built in the Arahama coastal area as a planting base by the Coastal Forest Restoration Project. It is feared that a rain pool and the hardness of a part of the embankment, which was built in early year, inhibited the growth of planted trees. Planting bases tend to become compacted by heavy construction machinery, which allows rain water to pool on the embankment. The physical properties of the embankment were investigated in Sendai City, Miyagi Prefecture, Japan. Most soil samples collected from a depth of lower than 75 cm (especially 10 to 40 cm) had the Yamanaka hardness index of higher than 20 mm, a bulk density of higher than 1.5 Mg m-3, and a coarse porosity of lower than 20%. The embankment was hard, densely packed and had low coarse porosity, indicating that the embankment has been compacted.
