IMPACT OF MODIFYING ADDITIVES ON THE CURING MECHANISM OF THE MAGNESIA-BISHOFIT COMPOSITION

Abstract

Addition of 5 % of phosphogypsum to the magnesia-bishofit composition reduces the setting time of the mixture and increases the strength of the stone, and together with 5 % of the ferrous sulphate additive it contributes to pore clogging with dehydrite particles and bonding flakes of Fe(OH)3, moreover, it improves the deformation phenomena during curing of the specimens, reduces their water absorption capacity and increases the strength.