Optimum Percentage of Fly Ash as Cement Replacement and Effect on Mechanical and Durability Properties of Self-Compacting Concrete

Abstract

Self-compacting concrete (SCC) is a type of concrete that does not require vibration and undergoes compaction under its own self-weight. Cement being the major constituent of self-compacting concrete is very expensive. Thereby incorporating fly ash, a by-product obtained by burning coal in coal power plants, the percentage of cement can be reduced. Thus in this study, class C fly ash in varying percentages from 0 to 30% has been used as a partial replacement of cement. The main purpose is to study the effects of fly ash on mechanical behavior and durability properties of self-compacting concrete and to choose the optimum dosage of fly ash. To determine the mechanical behavior, fresh properties of self-compacting concrete were studied by performing Slump flow, J-ring, V-funnel, and L-box tests. Hardened properties were evaluated by performing the Compressive strength and Split tensile test. The durability was determined using the volume of voids and sorptivity test. Tests to study mechanical behavior were performed by casting cylinder, whereas, concrete discs were cast to perform durability tests. Finally, it was observed that the replacement of 25% Fly ash with cement was found to be the optimum percentage.