Surface effects of molten slag spills on calcium aluminate cement paste

Abstract

Industries such as metal, ceramics and petrochemicals suffer from high temperature spills. Such events exert a unique form of loading in concrete structures that cannot be accurately simulated by heating of samples in an oven. Calcium aluminate cement (CAC) based concrete is the industry standard for such environment, and while much is known regarding its heating, literature considering hot spills on concrete surfaces is scarce. In this paper, slag is heated up to the same temperature as in a steel factory and then poured on top of cement paste samples with W/C ratios of 0.20 and 0.40. A combination of FEM, TGA, XRD and SEM/EDS was used to investigate the effects of hot spill on the samples. The rapid expansion caused by the thermal shock generated cracks in only some of the samples, while the high temperature environment and unidirectional escape of water caused chemical changes in all samples.

Keywords

• Calcium aluminate cement
• High temperature degradation
• Molten slag spill