Effect of admixtures on strength of concrete with the substitution of Aggregates

Abstract

In this world of rapid infrastructure development, Concrete is most widely used material after water. It comprises of conventional materials i.e. Cement, Sand, Aggregates & Water but in order to improve the overall properties of the concrete mix various admixtures are being added to the mix . Various alternative material are being tested by the researcher in order to partially replace with the parent materials and to utilize the agricultural and industrial waste which are available in abandoned. Concrete has good compressive strength but weak against flexural and tension thus concrete is reinforced with mild steel bars to bear tensile loading. Also, carbon emission from worlds concrete products and structures is of very high intensity because of chemical reaction, reducing the carbon percent from atmosphere by partially replacing indegredients. In this current study, I had tried to replace coarse aggregates from concrete with Crushed Quartize (100%), Gravel (100%) and thirdly Crushed Quartize (50%) and Gravel (50%) in M40 grade concret mix. Also, the superplastisizers Conplast SPG8 had been added to the mix in order to compare the values obtained from mix with and without admixtures. The ultimate aim is to find out the best type mix amongst these in terms of compressive strength.

The detailed study on determining the compressive strength for 7days, 14days, and 28days has been carried out with and without adding the admixture. Finally, the analysis has been done to find out the best type of aggregates with or without the admixture in the concrete.