Svojstva svježeg i očvrsnulog betona s dodatkom crvenog mulja i silicijske prašine (Fresh and hardened concrete properties containing red mud and silica fume)

In recent years, various studies have been conducted on the utilisation of bauxite residue from alumina production (known as red mud) in the construction industry. It is particularly noteworthy as a partial replacement for cement in concrete because of its favourable chemical composition. In this study, red mud and silica fume were investigated as partial replacements for cement in concrete. Five mixtures were tested. Herein, cement was replaced with red mud at 0, 5, 10, 15 and 20 % by cement mass. Furthermore, cement was replaced by silica fume at 10 % by cement mass in all the mixtures. The workability, bulk density, and air content were tested to evaluate the properties of the fresh concrete. The bulk density, water absorption, compressive strength, splitting tensile strength, water penetration, and freeze–thaw resistance were tested to evaluate the properties of the hardened concrete. The results indicated that for a low red mud content, reasonable fresh and hardened concrete properties were achieved.