Residual compressive strength of hardened OPC/CAC paste after fire exposure

摘要

Cementitious fire-retardant coatings are widely used for fire protection of structures. Recently, blended pastes of ordinary Portland cement (OPC) and calcium aluminate cement (CAC) have started to be used as binders in cementitious fire-retardant coatings, but the fire resistance and chemical composition of various OPC/CAC pastes are still not clear. The residual compressive strengths of binary cement pastes with various OPC/CAC ratios after fire exposure were studied in this work. The mineral composition and microstructure of the pastes were characterised by X-ray diffraction and environmental scanning electron microscopy/energy dispersive spectrometry, respectively. It was found that the paste with an OPC/CAC ratio of 60/40 was the most fire-resistant.