The effect of ultrafine fillers on the properties of cement-sand mortars

The possibility of fixing sandy soils with a cement-sand mortar based on finely ground slag and an expanding sulfoferrite additive is considered. Cement compositions for the preparation of cement-sand solutions were prepared by joint and separate grinding in a ball mill. Studies of the physical and mechanical, deformation and structural characteristics of cement-sand mortar in carbonate and carbonatesulfate media have been carried out. It has been established that under the influence of carbonate and sulfate ions a protective layer of calcium ferrite trihydrosulfide is formed, which prevents the pervasion of aggressive solutions into the cement stone, thereby providing compaction, hardening and expansion of the hardening system. (C) 2019 Elsevier Ltd. All rights reserved.