Study on manufacturing fine-grained concrete with compressive strength over 100 MPa using steel slag aggregate to replace sand

Abstract

Along with development of the economy, the increasing high-rise buildings and long span infrastructures required to utilize high strength materials. However, studies on high strength concretes with a higher 100 MPa in the compressive strength using steel slag as a fine aggregate have not been investigated in Vietnam. In this study, authors used steel slag aggregates (PS Ball) produced according to Slag Atomizing Technology (SAT), spherical shape with an average diameter of 0.4 mm to instead of sand (0, 30, 50, and 100%) in the matrix composition. Cement ButSon PCP40 and silica fume (SF90) were utilized as binders. The water per cement ratio was 0.2 and a superplasticizer was used to increase compressive strength and workability of concretes. Effects of different storage conditions including heat water, air, and water at different ages as well as different contents of silica fume (5, 15, and 25%) were investigated. The results indicated that as the content of steel slag aggregates increased, the workability of concretes clearly increased. The concrete with 50% steel slag aggregates and 25% silica fume cured at hot water (80^oC) for 3 days produced the highest compressive strength (102 MPa).