Mechanical properties of concrete at high temperature—A review

Abstract High temperature is well known for seriously damaging concrete micro- and meso-structure, which brings in a generalised mechanical decay of the concrete and even detrimental effects at the structural level, due to concrete spalling and bar exposure to the flames, in case of fire. Because of the relevance of concrete behaviour at high temperature and in fire, many studies have been carried out, even very recently, on cementitious composites at high temperature, and the most relevant parameters have been identified and investigated. Within this framework, the authors provide a comprehensive and updated report on the temperature dependency of such parameters as the compressive strength, modulus of elasticity, strength in indirect tension (bending and splitting tests), stress–strain curves and spalling, but the roles played by the water–binder ratio (w/b), aggregate type, supplementary cementitious materials (SCMs) and fibres are investigated as well. Among the objectives of the paper, the approaches currently adopted to improve concrete mechanical properties at high temperature are treated as well. Meanwhile, the influence of test modalities on the mechanical properties of concrete at high temperature is also discussed in the paper.