ABSTRACT
Degradation of concrete due to fire and high temperatures has been widely reported. Fire and high temperatures cause severe damage to concrete structures such as spalling of concrete and reduction of concrete strength (Arioz, 2007, Chan et al. 2000, Dale 2000, Felicetti & Gambarova 1998, Jensen et al. 1997, Luo et al. 2000, Poon et al. 2004, Short et al. 2000). Compared to normal strength concrete (NSC), many investigations suggest that high strength concrete (HSC) is more susceptible to explosive spalling and loss of strength when subjected to rapid temperature rising (Castillo & Durrani 1990, Kalifa et al. 2000, Sanjayan & Stocks 1993). Explosive spalling is a dangerous type of failure and could impair the integrity of a concrete structure (Xiao & Falkner 2006). In some cases, spalling can be extensive and may cause an immediate failure of the structure (Anderberg 1997). Some investigations (Atkinson 2004, Dale 2000, Kalifa et al. 2001) reported that utilizing polypropylene fibre (PPF) in concrete may considerably control the spalling behavior and reduce the amount of spalling of HSC at high temperatures.
