silica fume

The article presents the influence of pozzolanic additives and polycarboxylate superplasticizer on the performance of the cementitious matrix of recycled aggregate concrete. The particle size distribution by volume and surface area of fly ash and silica fume is given, and the phase composition and microstructure of cementing paste are investigated.

Concrete structures and elements are often exposed to different aggressive environment. It leads to failures, cracking, weathering and deterioration of concrete materials. Under aggressive conditions, the concrete is liable to a corrosive process which is not usually caused by one specific factor but by combination of aggressive media. Sulphur environment is one of the most corrosive factors influencing the concrete durability.