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Granite rock fines addition and its effects on self-compacting mortars’ properties

Abstract

The present study evaluates the use of granite rock fines (GRF) in self-compacting mortars, aiming to obtain adequate rheological characteristics without incorporating viscosity modifying additives. For this, mini Funnel-V, mini Slump Test and physical-mechanical characterization tests were carried out on reference mortars (without GRF) and with GRF substitution levels equal to 5%, 15% and 25%, to cement’s volume. The hydration of the pastes of these mortars was also evaluated using the isothermal calorimetry technique. Subsequently, the theoretical porosity of the pastes was analyzed through the compactness test, in order to obtain the interparticle spacing (IPS) of these pastes. When incorporating GRF, the viscosity of the mortar was adjusted, increasing the flow time by up to 4.3 sec, reducing cement consumption by up to 12% and, consequently, the release of heat during hydration. Furthermore, it was concluded that the incorporation of GRF reduces the porosity of mortars by up to 17.63% and increases the compressive strength by about 11% as a result of the addition of 15% FRG. However, due to the fact that the distance between the particles of the paste is reduced, the consumption of superplasticizer additive content has been increased to achieve the ideal spreading.

Keywords:
Self-compacting mortar; Granitic rock fines; Rheology; Heat of hydration; Mechanical properties

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