Properties of silicon manganese slag as an aggregate for concrete depending on cooling conditions

Abstract

When molten silicon manganese slag contacts with water, it is cooled down rapidly with much water vapor and to be a rock masses like as volcano rock. This porous rock may be used as a lightweight aggregate. In this study, we have tried to evaluate engineering properties of this material to use for construction fields. In the view point of engineering properties, such as low density and low water absorption, regular shape the aggregate cooled by air–water is comparatively superior to other cooling condition. Depending on the ratio of air to water, the size of the pore in aggregate is found to change, and the higher the ratio of water, the higher the average pore size. The effect of pore size and pore volume has a direct effect on mortar, and the dry shrinkage is low in mortar using air–water mixed rapidly cooled aggregates. In mortar engineering properties, the mortar replacing air–water mixed rapid cooled aggregate shows comparatively proper properties, such as unit weight of 1682 kg/3 and compressive strength of 22.9 MPa, which means that this lightweight aggregate has the possibility as a structural lightweight aggregate.