The SiO₂ content of iron ore tailings was 55.88%, the metallogenic geological environment was unique and complex in the study area. The tailings was low-silicon magnet with rich source of iron silicate tailings, mainly composed of quartz, amphibole and plagioclase. To maximize use of iron ore tailings, autoclaved aerated concrete (AAC) samples in the optimized plan were successfully prepared with a bulk density of 588 kg/m³ and compressive strength of 3.99 MPa after the iron ore tailings was milled for 25 min and silica sand for 30 min. The results showed that by analysis of X-ray and reaction mechanism the main mineral phases in the AAC products are 0.9 nm tobermorite, 1.1 nm tobermorite, 1.4 nm tobermorite, and C-S-H hydration products, ferrotschermakite, anhydrite, calcite, dolomite and residual quartz The high strength was obtained because the C-S-H gel as a binder and the tobermorite are cemented into each other.

iron ore tailings  /  autoclaved aerated concrete  /  tobermorite  /  C-S-H gel