Abstract
Utilization of soil fractions recovered from disaster debris as geomaterials was strongly desirable after the 2011 East Japan earthquake and tsunami because the soil fraction accounted for a third of the approximately 30 million-ton disaster debris and tsunami deposits. Because the quality of recovered soils varied according to treatment systems at each site as well as the characteristics of original seabed sediments, clarification of material properties of recovered soils is important for future catastrophes. In this research, a total of 404 data, which were archived in Iwate Prefecture, were analyzed to verify particularly the following two issues: 1) the properties of the recovered materials as geomaterial and their relationships with treatment methods, and 2) variation in the quality with treatment progress. A series of analysis indicated that the soil fractions recovered from disaster debris mostly satisfy requirements for utilization as geomaterials and have quality equivalent to general geomaterials, regardless of treatment progress. Some of the chemical and physical properties are significantly affected by additive materials, such as crushed concrete and a steel slag-based material, applied for the purpose of improvement.
