Durability and mechanical properties of high strength concrete incorporating ultra fine Ground Granulated Blast-furnace Slag

Ground Granulated Blast-furnace Slag (GGBS) is a green mineral admixture that improves the rheology of fresh concrete, and its ultimate mechanical and durability properties. Ultrafine GGBS (UFGGBS) has increased surface area which increases the apparent rate of hydration, pozzolanic reactions and has a better filling effect. Two concrete mixes with 450 and 520 kg/m3 of ordinary Portland cement and two more mixes of equivalent total cementitious materials with 30% UFGGBS replacement were cast. Compressive strength, flexural strength, modulus of elasticity, chloride migration, electrical resistivity and drying test results are presented. Concrete with UFGGBS has a higher early strength, lower permeability and improved durability even at 3 days of curing.

► The effects of ultra fine Ground Granulated Blast-furnace Slag on hardened concrete properties were investigated.
► The chloride migration coefficients and electrical resistivity measurements were recorded and studied.
► The increase in fineness of the blast furnace slag led to increase in apparent rate of hydration and pozzolanic reactions.
► The use of ultra fine slag improved the mechanical properties of the concrete even at 7 days of curing.
► The inclusion of ultra fine Ground Granulated Blast-furnace Slag improved the durability properties of the concrete.