Enhancing performances of clay masonry materials based on nanosize mine waste

Abstract

The development trend of building materials science is aimed at energy and resource conservation, as well as the creation of green composites. An important step in this direction is the disposal of waste of various origins, including mine waste. This study aims to increase the performances of non-autoclaved and autoclaved silicate materials using clay rocks, simultaneously recoverable during the extraction of iron ore. Binder composites, quicklime-sandy-sand and lime-cement, were prepared in the form of new compositions, based on which silicate products with improved strength properties and performance characteristics were developed. The synthesis of new growths in the “sandy clay raw- calcium hydroxide - water” system was also studied both under autoclaved conditions and without it. The features of the formation of the hydration phase and hardening of modified binders were investigated taking into account the chemical and microstructural features of sandy clay rocks. Meanwhile, the microstructural, morphological and thermal properties of the cured silicate products were also determined. Based on clay waste raw materials, weather-resistant silicate materials were obtained, the strength of which during operation can even increase due to the hydraulic properties of cementitious composites. Freeze-thaw resistance is 15 cycles, which corresponds to the performance of traditional bricks. An energy-efficient technological route for the manufacture of sand-clay-calcareous stones and blocks is proposed.