Properties of heavyweight concrete for structural and radiation shielding purposes

Abstract

In applications of concrete for shielding against hazardous radiation or for being used as counterweight, as well as in various other applications that involve the use of heavyweight concrete, the most significant method of mix design involves the use of heavyweight aggregates. Concrete mixes that were produced for this work contained iron ore, steel mill scale, two types of barite, and steel slag, which are the heavyweight aggregates available in Turkey. An additional heavyweight concrete mixture was also produced using magnetite as a natural mineral heavyweight aggregate. In all concrete mixes produced, water/cement ratio, cement content, and the maximum aggregate size of the aggregates used were kept constant. In terms of the main mechanical properties, the best performances were obtained when iron ore was used, while the highest fracture energy values were reached in concretes with steel mill scale, magnetite, or with the combination of steel slag, iron ore, and crushed sand. Another important objective of this research was to evaluate the radiation shielding properties of heavyweight concretes containing iron ore, steel mill scale, two types of barite, or steel slag as aggregates. The experimental results showed that the attenuation coefficient varied from 0.224 to 0.265 1/cm, while the unit weight of heavyweight concrete was increased from 3012 to 3820 kg/m(3). On the other hand, there is reasonably good agreement between theoretical and experimental results of linear attenuation coefficients. It can be concluded that the dominant factor in the determination of attenuation coefficient is the unit weight of heavyweight concrete and that the value of the coefficient is independent of the type of heavyweight aggregate used.