Blastfurnace slag as aggregate for concrete

Abstract

Summary Blastfurnace slag is an important source of dense aggregate for concrete. In an investigation lasting six years the Building Research Station has compared the properties of slag aggregates with those of crushed limestone and river gravel. Six slagsfromfive different works were tested, some being typical slags sold regularly for use as aggregate and others chosen to test the effect of specific chemical or physical characteristics. Concretes made with all these slags as coarse dense aggregate were tested for compressive and transverse strength, dimensional stability and sulphate resistance. Reinforced concretes were tested for metal corrosion. A number of tests were also made on concretes in which slag constituted both the coarse and the fine aggregate. The present paper gives the results of all these studies except the observations made concerning reinforced concrete which are the subject of a separate paper in this issue. It is shown that blastfurnace slags currently produced provide material for coarse aggregate for concrete which is satisfactory in every respect.