Influence of superplasticizer family on the durability characteristics of fly ash incorporated cement concrete

Abstract

Nowadays, researchers are focusing on developing more durable cementitious matrices. Major durability problems are associated with sulphate attack, acid attack, chloride penetration etc. The important method to improve the durability characteristics of concrete is to reduce the permeability of concrete by giving good compaction. Superplasticizer addition is one of the methods to improve the workability and thereby reducing the porosity. A large amount of CO2 is emitted into the atmosphere from the cement plants during the calcination of CaCO3 and also through the burning of fuel in the kiln. The environmental pollution can be reduced by replacing the cement with the pozzolanic materials like fly ash. Portland pozzolana cement (PPC) is nowadays considered as a sustainable substitute of ordinary portland cement (OPC). The combined influence of pozzolanic and superplasticizer from four different families on the durability properties of concrete and mortar is studied is in this work by conducting laboratory tests like the sorptivity test, acid resistance test, RCPT test and sulphate resistance tests. In this study sorptivity value of the superplasticized mixes are found to be less than that of control specimen without superplasticizer. In all durability related aspects, the mixes with PCE based superplasticizer showed better performance than the control mix and that of mixes with other families of superplasticizer. Improvement in durability characteristics is observed for the mixes containing commercially available PPC compared to the mixes prepared with site blended PPC (ie OPC + 25% FA).