Postfire full stress-strain response of fire-damaged concrete

This paper reports experimental data establishing the postfire full stress–strain response of fire-affected concrete. Such data are useful in situations when redesign of fire-damaged concrete elements is considered. Heating was carried out to various temperatures in the range 217–470°C. Cooling was carried out either by quenching or in air. The postfire strain at ultimate stress significantly increased after heating to temperatures higher than 320°C. Quenching seems to aggravate the loss in compressive strength and further increase the strain at ultimate stress. Quenching involved spraying the heated concrete with tap water for 5 min. It is evident that knowledge of maximum temperature of exposure alone is not sufficient for estimation of the postfire stress–strain relationship. Other characteristics of exposure such as method of cooling are also important in evaluating the modification in the structural behaviour of fire-affected concrete. Copyright © 2005 John Wiley & Sons, Ltd.