ANALYSIS OF RC FRAMES UNDER ELEVATED TEMPERATURES

Abstract

The practical implementation of performance-based fire safety design of reinforced concrete (RC) structures hinges on the availability of accurate numerical simulation tools for the behaviour of RC members exposed to fire. Finite element analysis requires properties of materials as an input for simulation in extreme conditions, hence it is important to have a first-hand knowledge of the works done by other researchers in this field. A variation of models are required to be studied which enables us to comment upon the consistency of results from a particular model. Models of various researchers have been studied and used. Major contents covered are compressive and tensile strength of concrete and steel at both elevated temperatures and cooled down stage. Also mechanical properties like stress-strain curves at elevated state and after exposure has been studied. Another component of this study was the inclusion of bond strength between concrete and steel interfaces at elevated temperatures and after exposure. Using these available studies analytical methods were used to obtained performance parameters of RC elements like beams and columns. These performance parameters includes moment curvature relationships for beams and interaction diagrams for columns. Later these results were used to perform a successive failure analysis of a RC frame and to determine failure load.