Compressive Strength of Concrete With Fly Ash, Nanosilica and Recycled Aggregate

Abstract

In this study, concrete mix was prepared using recycled aggregates (RA) which were retrieved from demolished concrete blocks. Pozzolanic materials like fly ash (FA) and nanosilica (NS) were used as partial replacement of cement by weight in varying percentages i.e. 10%, 20% 30% and 2%, 3%, 4% respectively. The experimental work was focused on investigating the effect of nanosilica and fly ash on fresh properties and compressive strength of recycled aggregate concrete (RAC). To examine the fresh properties of concrete, slump test was performed for workability requirements. It was observed from experimental results that with the increase in percentage of recycled aggregates in concrete, compressive strength decreases but workability was not affected up to 50% variation of recycled aggregates. Results showed that with the addition of nanosilica compressive strength of concrete was increased but workability was decreased with the increase in percentage of nanosilica. The use of fly ash in addition to nanosilica (30% RA+3% NS + 10% Fly Ash) improved both the workability and compressive strength of recycled aggregate concrete (RAC).