Influence of ground mineral admixtures on pore structure of cement paste with superplasticizer

Influence of singly or compositely adding steel stag, blast furnace slag and fly ash on pore structure of harden blended cement paste with superplasticizer was studied by mercury intrusion porosimetry (MIP). The results show that pore structure of cement paste was worse at early age by singly and compositely adding any kind of mineral admixtures. At later age, both blast furnace slag and steel slag obviously reduce porosity of cement paste and both blast furnace slag and fly ash obviously reduce median pore diameter and improve pore diameter size distribution. At later age, sequence of decreasing porosity capacity is blast furnace slag > steel slag > fly ash, while sequence of reducing median pore diameter and improving pore size distribution capacity is blast furnace slag > fly ash > steel slag. Pore structure of cement paste at later age can be improved by compositely adding mineral admixtures.