Canadian use of ground granulated blast-furnace slag as a supplementary cementing material for enhanced performance of concrete

Abstract

The performance of concrete, in terms of its placeability, physical properties, and its durability, can be enhanced by the use of slag-blended cements or separately added ground granulated blast-furnace slag. It also has advantages for architectural purposes due to the whiteness it imparts to concrete. Properly proportioned and cured slag concretes will control deleterious alkali-silica reactions, impart sulphate resistance, greatly reduce chloride ingress, and reduce heat of hydration. Setting times and early age strengths can be controlled through appropriate proportioning, while later age properties are typically enhanced. CSA and ASTM standards cover both slag-blended cements (CSA A362; ASTM C595; ASTM C1157) and slag as a supplementary cementing material (CSA A23.5; ASTM C989). Since Lafarge introduced the first large-scale slag grinding plant near Hamilton in 1976, slag has become the predominant supplementary cementing material in Ontario. Recently, its availability in the U.S. has expanded dramatically.

Effect of Water-to-Binder Ratio, Air Content, and Type of Cementitious Materials on Fresh and Hardened Properties of Binary and Ternary Blended Concrete

“…When one parameter is kept constant, increasing w/b or air content slightly increased the shrinkage due to the increased paste volume. This result is expected since shrinkage is affected by the volume of cement paste in concrete (Hale et al 2008, Hooton 2000. Since the paste volume was not significantly different for all, the shrinkage for all mixtures would not have been expected to be dramatically different (Hale et al 2008).…”

“…However, increasing the fly ash replacement dosage from 15% to 30% did not significantly affect the compressive strength. For a given w/b and nominal air content, increasing the slag cement replacement dosage increased the 28-day compressive strength (Hooton 2000). Ternary mixtures containing Class F fly ash and slag cement exhibited higher strength than the binary mixtures with Class F fly ash, due to the contribution made by slag cement.…”

“…For a given w/b, increasing the replacement dosage of slag cement further increased the resistivity of binary mixtures. This is likely due to the effect of slag cement on increasing the density of the microstructure and blocking capillary pores with secondary hydration products which results in reducing the porosity of the ITZ, thus decreasing the overall permeability compared to the control mixture (Wee et al 2000;Hooton 2000;Bijen 1996). Ternary mixtures with Class F fly ash and slag cement showed higher resistivity than the ternary mixtures with Class C fly ash and slag cement.…”

Analysis of the Utilization of Air-Cooled Blast Furnace Slag as Industrial Waste Aggregates in Self-Compacting Concrete

“…The convenience of slags as aggregate in concrete will depend on the properties that have to be achieved in fresh and hardened states. In this way, according with some authors [8], the concrete that is produced with blast furnace slag as fine aggregates provides more workability when fresh, easily the vibration and making a better compaction with less entrapped air. Nonetheless, the depletion of natural aggregates as well as the consumption of large amounts of energy on the production, transportation, and use of raw materials, should be considered when producing concrete [9].…”

Reactivity of modified iron silicate slag as sustainable alternative binder

“…These slags can be used as SCM without modification and can satisfy the requirements of demanding construction applications. In terms of literature, a wide range of publications has proven that usage of amorphous materials such as metakolin and blast furnace slags in combination with OPC can enhance the mechanical properties and durability of concrete (Werner et al, 1987;Hooton, 2000;Siddique and Klaus, 2009;Juenger et al, 2011).…”