ソンマ・ヴエスヴィアーナ, ローマ時代遺跡のコンクリートの性状

抄録

Roman concrete in Somma-Vesuviana Ruins was investigated. Internal concrete consists of the cementitious material and a big aggregate of the size from 100 to about 200 mm, and the surface concrete is composed of the cementitious material and the aggregate of the size of 30 mm or less. Big aggregates were a yellow tuff and black tuff, and the brick was used as a small aggregate. In a black tuff, Leucite, Orthoclase, and Biotite are included. In a yellow tuff, the XRD peak of Leucite and Biotite are strong, and the XRD peak of Orthoclase has become small. In the XRD pattern of brick, the peak of Orthoclase and the halo of 20-35° of the amorphous material appeared greatly. Mortar was composed of calcite and amorphous SiO₂. Therefore, it was presumed for pozzolann cement that consisted of the lime or slaked lime and the volcanic ash to have been used. Carbonated concrete using pozzolann cement in the air or underground remained in the soil at a long term of 1500 years or more. The possibility for concrete to have the long-term durability was suggested.