Thermal and mechanical properties of concrete and its constituents at elevated temperatures: A review

To retrofit a fire damaged structural element, it is important to understand the extent of thermal exposure of such structural element. It is presumed that the extent of damage of fire affected structural elements may be assessed with the knowledge of the properties of their constituent materials at elevated temperatures. The fire resistance of concrete and temperature propagation inside the structural element depends on the thermal and mechanical properties of the ingredients and also on concrete heterogeneity and its compactness. Different crystallographic arrangements of materials result in differential thermal expansion of cement-sand matrix and coarse aggregates. Since concrete consists of a major proportion of coarse aggregates, special focus has been given on the thermal and mechanical properties of different types of coarse aggregate at elevated temperatures. The objective of this paper is to present a brief critical review of the thermal and mechanical properties of different types of concrete and its constituents at elevated temperatures and highlight certain areas that may be explored further by researchers.