Properties and corrosion behaviour of applicable binary and ternary geopolymer blends

Abstract

This article outlines the contribution of various precursors named ground-granulated blast furnace slag (slag) and metakaolin (MK) as a binary blend (s70m30) as well as slag, MK and fly ash (FA) as ternary blends on the properties and corrosion behaviour of geopolymer pastes. Different mixtures were activated with an alkaline activator solution and exposed to different curing conditions. Physico-mechanical characterisation of the specimens was conducted by measuring activator solution/binder ratio, bulk density, total porosity and compressive strength. Two different methods were used to evaluate the corrosion behaviour of steel embedded in the selected specimens cured in seawater. Laboratory techniques of differential thermal analysis (DTA) and Fourier-transform infrared spectroscopy (FTIR) were used to study the thermal analysis and the molecular of the samples. The results showed that the ternary blends of 50% slag, 40% MK and 10% FA (s50m40f10) exhibited the highest compressive strength, the lowest porosity and the lowest corrosion rate, whilst the blends of 60% slag, 30% MK and 10% FA (s60m30f10) came in the second place.

Keywords

• ternary blends
• compressive strength
• porosity
• corrosion behaviour
• slag
• metakaolin
• fly ash