Effect of Addition of Fly Ash on Workability of Concrete

Fly ash varies significantly in composition. It is residue left from burning coal, which is collected on an electrostatic precipitator or in a bag house. It mixes with flue gases that result when powdered coal is used to produce electric power. Fly ash is a pozzolanic material which produces calcium-silicate-hydrate (C-S-H) when reacts with free lime present in cement during the hydration. Use of fly ash in concrete imparts several environmental benefits and thus it is eco-friendly. It saves the cement requirement for the same strength thus saving of raw materials such as limestone, coal etc required for manufacture of cement. Fly ash is pozzolanic material& it improves the properties of concrete like compressive strength& Durability. This paper present the experimental result carried out to determine workability and compressive strength of concrete at different replacement of PPC. Under this project percentage replacement are 5 percent, 10 percent and 15 percent in the concrete. The addition of fly ash improves the strength of concrete. When 5 % fly ash is added to the concrete then the strength and workability both increases but when we add 10 % and 15 % at both percentages the strength as well as the workability of the concrete decreases. So this clears that the best replacement of cement is with the addition of 5 % of fly ash to obtain better results.