High water content shielding concrete with iron and bauxite aggregates

Abstract

Since limonite ores available in Hungary do not satisfy the general quality requirements for reactor shielding concrete aggregates because of insufficient crystallinic water and low density, the possibilities of using bauxite instead of limonite were explored. Though the density of bauxite is still lower than that of Hungarian limonites, there are types with more than 25% hydrate water content. Use of bauxite as concrete aggregate resulted in a hydrate water content exceeding that of best limonite concretes of abroad, while sufficient specific density can be provided by the addition of a due percentage of scrap iron. This new type of concrete has adequate mechanical and thermal characteristics, and a hydration water content to be considered stable in spite of chemical reactions between the Ca(OH)2 set free of the cement on one hand, and bauxite on the other hand. This research concluded with the establishment of empirical formulae for the relationship between concrete composition and neutron attenuation.