Thermal properties of high strength concrete at elevated temperatures

In recent years, high strength concrete (HSC) has become an attractive alternative to traditional normal strength concrete (NSC). With the increased use of HSC, concern has developed regarding the behaviour of such concrete in fire. Studies are in progress at National Research Council of Canada for developing design guidelines for the use of HSC under fire conditions. The behaviour of HSC columns is illustrated by comparing the fire resistance performance of HSC columns with that of NSC columns. Results from experimental studies that were carried out to determine the thermal properties of HSC, with and without steel fibre-reinforcement, at elevated temperatures are also presented. The effect of temperature on thermal conductivity, thermal expansion, specific heat and mass loss of HSC is discussed. Test data indicate that the type of aggregate has significant influence on the thermal properties of HSC, while the presence of steel fibre-reinforcement has very little influence on the thermal properties of HSC.