STUDY ON CONCRETE USING STEEL SLAG AS COARSE AGGREGATE REPLACEMENT AND ECOSAND AS FINE AGGREGATE REPLACEMENT

Concrete is the third largest material consumed by human beings after food and water as per WHO. Concrete plays a vital role in the design and construction of the nation’s infrastructure. Almost three quarters of the volume of concrete is composed of aggregates. These are obtained from natural rocks and river beds, thus degrading them slowly. This issue of environmental degradation, and need for aggregates demands for the usage of any other alternative source. Thus the concept of replacement of coarse aggregate with steel slag and fine aggregate with ecosand seems to be promising. In this study an attempt is made to use steel slag, a by-product from steel industry as replacement for coarse aggregate in concrete and eco sand which is a commercial by-product of cement manufacturing process introduced by ACC Cements as fine aggregate replacement. Initial optimization of materials was done with 7 days strength. M30 grade of concrete was used. Possible optimum replacement of slag material was found to be 60% and possible optimum replacement for ecosand was found to be 40%.Tests on compressive strength, flexural strength, split tensile strength at 7 days and 28 days, and water absorption at 28 days were conducted on specimens. It was concluded that replacing some percentage of coarse aggregate with steel slag enhances the strength. The results showed that replacing about 60 percent of steel slag aggregates for coarse aggregate and 40 percent of ecosand for fine aggregate will not have any adverse effect on the strength of the concrete.