Effects On Compressive Strength When Cement Is Partially Replaced By Fly-Ash

The present paper deals with the effect on strength and mechanical properties of cement concrete by using fly ash. The utilization of fly-ash in concrete as partial replacement of cement is gaining immense importance today, mainly on account of the improvement in the long term durability of concrete combined with ecological benefits. Technological improvements in thermal power plant operations and fly-ash collection systems have resulted in improving the consistency of fly-ash. To study the effect of partial replacement of cement by fly-ash , studies have been conducted on concrete mixes with 300 to 500 kg/cum cementious materials at 20%, 40%, 60% replacement levels. In this paper the effect of fly-ash on workability, setting time, density, air content, compressive strength, modulus of elasticity are studied Based on this study compressive strength v/s W/C curves have been plotted so that concrete mix of grades M 15, M 20,M 25 with difference percentage of fly-ash can be directly designed.