Research of interrelation between volume deformation, composition and structural characteristics of magnesia binding materials

The article studies the modification process of volume deformations of magnesia binders at hardening depending on the composition and structural features which are determined by the feed stock burning parameters. The research is made to identify the possibility of expansion of the raw material base to produce magnesia binders and construction materials by using mining and concentration complex wastes. Magnesia binding materials obtained on the basis of magnesite with significant impurity content from the dumps of mining plants are studied by the analysis of mineralogical and phase composition with the help of X-ray phase and derivatographic analysis. The burning of the source rock is carried out under different temperature conditions to obtain binders of a different activity. The normal content of the hydrate phases in the hardened magnesia stone obtained on the binders of a different degree of activity is determined. The features of volume deformations in magnesia stone are revealed depending on its phase composition. The effect of crystals of hyper and hypo activity as well as calcium oxide crystals on magnesia stone soundness and integrity is described in the article.