The experience of using blast furnace slag as an artificial foundation of the building foundation is considered. In the process of construction and installation works, the displacement of the columnar foundations was revealed due to changes in the initial properties of the blast-furnace slag. The chemical composition of the slag belonged to the group of inert materials. In fact, after layer-by-layer compaction, the process of disintegration of its initial properties began. The analysis of the conducted studies showed that in the regulatory and scientific literature there are no unambiguous recommendations on the use of this material as the base of buildings and structures. The recommendations that are available relate exclusively to its use in road foundations. From experience it follows: the use of slag in construction is possible, subject to confirmation of its compliance with specific construction conditions.

Keywords: blast-furnace slag, artificial base, layer-by-layer compaction of the soil, hydraulic activity and inertness, modulus of basicity, calcium oxides, manganese oxides, particle size distribution, inert material, chemical decomposition