Effects of magnesium sulfate attack on ordinary portland cement (OPC) mortars

Abstract

The chemical and mineralogical compositions in Ordinary Portland Cement (OPC) were determined and cement which is low of C3A is more easily exposed to sulfate environment. The relation between physical strength of mortars sized 150 × 150 × 150 mm and the effects of different concentrations of sulfate solutions, SO4 2- (1%, 3% and 5%) for 3, 14 and 28 days was found to be that stronger the sulphate concentrations, the greater the sulfate attack, but in a weaker concentration situation, the attack was more efficient as the comparable damaged being achieved with smaller amount of sulphate. The morphological studies were observed under scanning electron microscope (SEM) and the distribution of the main component, including Mg2+ and SO4 2- ions, was analysed by Energy Dispersive X-Ray Analyzer (EDS) to observe the cracks and reactions.