Experimental study on rule of radioactive change of red mud concrete

Red mud was used to partially replace cement to prepare red mud concrete, with replacement rate of red mud mass being 0%, 5%, 10%, 15% and 20% respectively, and hydration age being 3d, 28d and 90d. The experiment of cube compressive strength and radioactivity were conducted for 90 cubical test pieces respectively. The results show that with rise of replacement rate of red mud, the cube compressive strength of red mud concrete at the same hydration age first increased and then decreased, leading to increase of content of 226Ra,232Th,40K in red mud concrete, and increase of material's radioactivity accordingly; as hydration age was prolonged, with the replacement rate of red mud being the same, the compressive strength increased, and internal and external exposure indices and total specific activity all increased yet with small increase range. Generally the hydration age does not significantly influence the radioactivity of red mud concrete.