Effect of Addition of Fly Ash on Workability of Concrete

Anuj Kumar, Dr. R. K. Tewatia

Abstract: 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.

Keywords: FLY ASH, CONCRETE