Enhancing elevated temperature performance of alkali activated slag-dolomite concrete with Fly ash

Abstract

Cement production is a significant contributor to the emission of CO₂ and the resulting planetary heating, thus necessitating the utilization of alternative materials. The superior durability and strength of geopolymer concrete have led to its use as an equivalent material to cement concrete. Fewer research has been conducted on the traits of geopolymer concrete at exacerbating temperatures. Therefore, what this study aims to do is thoroughly examine how geopolymer concrete behaves during extreme temperatures. Principal focus of this work is the investigation of GGBS-dolomite geopolymer concrete (GGD-GPC) at high temperature composed of dolomite, a byproduct of rock crushing plants, and GGBS, waste from the steel industry. Research now underway indicates that the resistance to high temperatures of this new geopolymer concrete is lower than that of concrete. To eliminate the problem, fly ash was added to the combination in different proportions since its incorporation in GPC results in sulphoaluminate gel, which is resistant to high temperatures. After being heated to 500 °C, each mixture is allowed to cool naturally and its compressive strength is assessed. Through this study, it is inferred that the mix of optimum temperature resistance consists of GGBS, fly ash and Dolomite in the ratio of 50:40:10 (GFD-GPC). To compare and check the high-temperature performance of these two geopolymer variants, these are subjected to temperatures 26, 100, 300, 500 and 700 °C and mass loss, strength in compression, dynamic modulus of elasticity (DME) and ultrasonic pulse velocity (UPV) are tested.