A study on geotechnical properties of recycled geomaterial from tsunami-related sediments

Abstract

Due to the 2011 off the Pacific Coast of Tohoku Earthquake, a large scale tsunami hit the Pacific coast area of the Tohoku and North-Kanto Regions, Japan. As a result of the earthquake and the subsequent tsunami, the tsunami-related sediments of about 900,000 tons were generated in Kesennuma City, Miyagi Prefecture. Therefore, the tsunami-related sediments had to be properly treated from the viewpoint of being recycled as non-toxic geomaterials and certainly utilized as embankments or filling materials in reconstruction projects. Additionally, it was required that they were quickly treated in order to preserve the living environment of local inhabitants and to improve the public health. In a disaster waste management project by the Miyagi prefectural government in Kesennuma (Kesennuma treatment area), the treatment (soil modification, separation, immobilization, etc.) and recycling of tsunami-related sediments were completed in about one year. This paper summarizes the outline of the treatment of tsunami-related sediments and describes the geotechnical properties of recycled geomaterials in the Kesennuma treatment area.