Experimental Study on Strength Reduction Factor in Concrete Specimen Subjected To High Temperature

Abstract

The concrete loses its strength and stiffness when exposed to high temperatures as they accumulate damage. The primary question remaining after a exposure to high temperature is what level of residual strength and the stiffness exists for material. This residual strength is particularly important for high-rise structures where post-fire decision-making hinges on functionality of the columns. This study specifically addresses the experimental program carried out to assess the residual compressive strength of cube specimens. Three type of concretes viz normal , high strength and fly ash concrete specimens were considered. These specimens are tested in two separate condition states. The first representing air-cooled state involves heating the specimen to the required temperature for prescribed duration and air cooled to the room temperature. Phase two involves heating the specimen to the required temperature for the prescribed duration and immediately cooled to the room temperature by immersing it in the water or called water quenched. The strength and stiffness degradation of concretes for various grades has been studied and compared with the similar studies carried by other researchers.