1986 年 369 巻 p. 16-22
This paper is concerned with the reaction between the alkalis present in the pore fluids of the cementitious phase of concrete and glassy orthopyroxene andesite occuring in the Setouchi volcanic rocks in Japan. Geological and petrogical characteristics of the Sanukitoid are investigated. Alkali-silica reactivity of Sanukitoid is tested by ASTM method and cement alkali content which shows deleterious expansion by ASTM mortar bar method is obtained. Formula which can predict the pessimum content of reactive aggregate for given mortar mix proportions with certain alkali content is presented by the function of critical alkali silica ratio. Alkali content which does not show deleterious expansion in mortar and concrete is obtained experimentally.