DefinePK

Abstract

A detailed 3-Dimensional time domain transient thermal stress finite element analysis was carried out to study the performance of reinforced concrete beams exposed to fire attack. A FE model that represented a reinforced concrete beam continuous over one support was developed. The beam was subjected to ASTM E119 standard fire exposure to the bottom and side surfaces, in the form of transient temperatures versus time, while maintaining constant transverse loading on top surface. Material nonlinearity was taken into account because of the changes in material properties experienced in fire. The more complicated aspects of structural behavior in fire conditions, such as thermal dilation, cracking or crushing of concrete, and yielding of steel were modeled. The validation of the applicability of the FE model was illustrated by comparing the finite element solution with the results of experimental testing carried out for similar RC beams within the same boundary conditions. The FE analysis showed that a reinforced concrete flexural member properly designed to fail in flexure at ambient conditions, would experience the same mode of failure when exposed to realistic fire exposures.