The Experimental Study on Behaviour of Blended Cement Concrete with 80% Replaced with Nano-Metakaolin and Steel Slag at Elevated Temperature

The effect of high temperature up to 800°C on concrete with 80% replacement of fine aggregate using nano-metakaolin, 80% replacement of fine aggregate using steel slag and their hybrid mix is compared to conventional concrete in this research work. Ordinary Portland cement containing fly ash is used as blended cement to prepare the concrete mix. M 30 grade concrete with water cement of 0.45 is used for the study. The project work involves casting of cubes (150mm x 150mm x 150mm), cylinders (150mm diameter and 300mm height) and prism (100mm x 100mm x 500mm). The concrete specimens are cured under water for 28 days and expose to 400 °C, 600 °C, and 800°C for 1 hour. The compressive strength, spilt tensile strength and flexure strength are measured for these specimens and compared with the strength of conventional concrete. The strength of each mix is found to increase compared to conventional concrete and a greater increase in strength is observed in mix with partial replacement with nanometakaolin. The strength is found to increase up to 600 °C and showed to decrease at 800 °C.