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U posljednjih nekoliko godina proveden je odrđeni broj istraživanja o korištenju ostataka boksita iz proizvodnje aluminija (poznatog kao crveni mulj) u građevinskoj industriji. Zbog svojih povoljnih kemijskih svojstava, ovaj materijal posebno je zanimljiv kao djelomična zamjena cementa u betonu. U ovom su istraživanju proučavani crveni mulj i silicijska prašina kao djelomične zamjene cementa u betonu. Ispitano je pet mješavina u kojima je cement zamijenjen s 0, 5, 10, 15 i 20 % crvenog mulja. Osim toga, u svim mješavinama cement je zamijenjen s 10 % silicijske prašine u odnosu na masu cementa. Da bi se odredila svojstva svježeg betona, ispitani su obradivost, gustoća i udio zraka. U očvrsnulom stanju ispitani su gustoća, upijanje vode, tlačna čvrstoća, vlačna čvrstoća cijepanjem, prodor vode i otpornost na smrzavanje i odmrzavanje. Rezultati su pokazali da se kod betona s manjom količinom crvenog mulja dobivaju zadovoljavajuća svojstva u svježem i očvrsnulom stanju., 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.