To study the partial replacement of cement by ggbs and natural sand by manufactured sand in concrete using different dosages of admixture

As we all familiar with the term concrete that, it is a mixture of cement, fine aggregates, coarse aggregates & water. Cement manufacturing industries liberates about 1 tonne of Co2 in the atmosphere while producing 1 tonne of cement. Similarly fine aggregates i.e. natural sand is increasingly becoming scares and costlier day by day. In order to meet the demands, concrete industry are constantly looking for supplementary cementitious materials and fine aggregates. Fly ash, ground granulated blast furnance slag, rice hush ash & manufactured sand are the industrial wastes and this materials can be used as supplementary to cement and fine aggregates by partially replacing it. In this experimental investigation, natural sand (NS) is partially replaced with manufactured sand (MS) & cement is partially replaced with GGBS. This experimental investigation is carried out in two phases, in 1st phase M30 grade of concrete is produced by replacing 0%, 20%, 40%, 60%, 80% & 100% of NS by MS with addition to three different dosages of admixture to determine optimum percentage of replacement of NS By MS & optimum admixture content at which max compressive strength is obtained. It is found by results that, when 60% of NS is replaced with MS with 1.50% of admixture max strength is achieved. In 2nd phase cement is replaced by 10%, 20%, 30% & 40% of GGBS with different dosages of admixture. It is observed that as dosage of the admixture increases strength also increases.