The development of high-strength mortars with improved thermal and acid resistance

Granulated blast furnace slag (GBFS) cement, containing up to 60% slag, is sometimes used in repair materials applied at intermediate temperatures of 150-300 °C. Low rate of strength development, especially at early ages, is considered a common disadvantage of repair mortars based on slag cement. The present research was oriented to improving a GBFS-portland cement binder for application as a repair material in the chemical industry when high thermal or acid resistance is required. It was found that the enhancement of GBFS-portland cement-based materials can be achieved with the help of silica fume (SF) and a superplasticizer (SP). The effect of different SPs on the compressive and flexural strength of SF-blast furnace slag-portland cement mortars was investigated. These mortars, in addition to high strength, demonstrate high thermal and acid resistance.