Effect of finely ground filler on the properties of slag-alkaline binder based on blast furnace slag
Abstract
Effect of finely ground filler on the properties of slag-alkaline binder based on blast furnace slag
Incoming article date: 20.12.2024The aim of this study was to determine the effect of finely ground filler on the properties of slag-alkali binder based on blast furnace slag. An aqueous solution of sodium silicate and caustic soda (aqueous solution of NaOH) was used as a hardening activator with an alkali modulus (weight ratio SiO2/Na2O) equal to 1.0 and 0.5. The results showed that the introduction of Reftinskaya GRES fly ash into the binder instead of ground blast furnace granulated slag causes an increase in the initial setting time, but does not affect the final setting time. No cracking was detected during hardening in mixtures containing fly ash, provided that a complex based on sodium silicate and an aqueous solution of NaOH was used as a hardening activator. The introduction of alkali into the sodium silicate solution helps to reduce the silicate modulus (the mass ratio of SiO2/Na2O) and reduce the formation of shrinkage microcracks due to the formation of a homogeneous structure and the formation of fly ash and the formation of sodium hydroaluminosilicate (H-A-S-N).
Keywords: cement paste, ground granulated slag, fly ash, hardening activator, setting time, shrinkage, microcracks