Effect of silica fume and lateral confinement on fire endurance of high strength concrete columns

Abstract

Fire represents one of the most severe environmental conditions, and therefore should be properly accounted for in the design of structural members. The increased use of high strength concrete (HSC) in buildings has raised concerns regarding the behaviour of such concrete in fire. In particular, spalling at elevated temperatures, as identified in studies by a number of laboratories, is a main concern. In this paper, results from experimental studies on the fire resistance of HSC columns are presented. A comparison is made of the fire resistance performance of HSC columns with and without silica fume and with different confinement configurations. The effect of silica fume and the effect of confinement on the fire performance of HSC columns will be discussed. The results show that the fire endurance of HSC columns with higher silica fume content is lower and the reduced tie spacing and the provision of cross-ties are beneficial in minimizing the spalling in HSC.Key words: fire resistance, high strength concrete, reinforced concrete columns, spalling.