Mechanical Fracture Properties of Alkali-Activated Slag with Graphite Filler

Mechanical Fracture Properties of Alkali-Activated Slag with Graphite Filler

Paper in proceedings (conference paper)

Alkali-activated slag is a building material considered as alternative to ordinary Portland cement based materials. Addition of graphite powder increases its electric conductivity, hence, introducing new functionality to building materials such as selfsensing and self-heating properties. In this study, the effect of graphite filler on the mechanical fracture properties of alkaliactivated slag composite is investigated. Graphite powder was added in the amount of 5, 10 and 15% with respect to the slag mass. Modulus of elasticity, fracture toughness and fracture energy were determined using standard three-point bending test on prismatic specimens with central edge notch. The course of fracture tests was also monitored by acoustic emission (AE) method. Compressive strength was determined on the fragments remaining after the fracture tests. Results showed that addition of graphite caused a decrease in compressive strength, fracture toughness and fracture energy but modulus of elasticity increased. Addition of graphite also caused a decrease in AE events and increase in amplitude of signals. This implies that mortars with graphite filler is more brittle than the reference mortar, and lower number of much larger cracks is formed during the fracture test.

Alkali-activated slag is a building material considered as alternative to ordinary Portland cement based materials. Addition of graphite powder increases its electric conductivity, hence, introducing new functionality to building materials such as selfsensing and self-heating properties. In this study, the effect of graphite filler on the mechanical fracture properties of alkaliactivated slag composite is investigated. Graphite powder was added in the amount of 5, 10 and 15% with respect to the slag mass. Modulus of elasticity, fracture toughness and fracture energy were determined using standard three-point bending test on prismatic specimens with central edge notch. The course of fracture tests was also monitored by acoustic emission (AE) method. Compressive strength was determined on the fragments remaining after the fracture tests. Results showed that addition of graphite caused a decrease in compressive strength, fracture toughness and fracture energy but modulus of elasticity increased. Addition of graphite also caused a decrease in AE events and increase in amplitude of signals. This implies that mortars with graphite filler is more brittle than the reference mortar, and lower number of much larger cracks is formed during the fracture test.

Fracture test; Alkali-activation; Slag; Graphite; Acoustic emission

Fracture test; Alkali-activation; Slag; Graphite; Acoustic emission

ROVNANÍK, P.; ŠIMONOVÁ, H.; TOPOLÁŘ, L.; KERŠNER, Z.

2018

02.06.2017

Elsevier

Netherlands

Structural and Physical Aspects of Construction Engineering

1877-7058

Procedia Engineering

190

2017

United Kingdom of Great Britain and Northern Ireland

43

48

6

http://www.sciencedirect.com/science/article/pii/S1877705817324451