Modeling the Influence of Limestone Filler on Concrete: A Novel Approach for Strength and Cost

The use of limestone fillers as additions in concrete has grown because they present several advantages over ordinary cements. Production of composite cements has caused a necessary shift in the manufacture process used in the cement industry. Now, it is known that the separate grinding and mixing technology is more convenient in order to produce these cements, called market-oriented or tailor-made cements. However, their optimum formulations require the help of methods of experimental design. In this study, the incorporation of limestone fines and their optimal is analyzed in concrete, where Portland cement was replaced by up to 42 %. The fillers were chosen to be of various particle sizes. The resulting concretes are compared for compressive strength, cement consumption and economic viability. The results obtained indicate the advantage of incorporation of limestone fines in the concretes, as for the same compressive strength at 28 days, savings up to 23% in the consumption of cement were achieved, which represents a significant reduction of energy, raw material consumption and costs. The XRD analyses of samples cured up to 28 days showed that this amelioration is due to formation of new hydrated compounds. It is concluded that an addition of finely ground limestone filler up to 18% gives a better strength for the same cement content and reduces the cost of concrete for the same target strength.