FIRE RESISTANCE OF FERROCEMENT ENCASED R. C. COLUMNS

Abstract

This dissertation is a theoretical and experimental investigation on the behaviour of ferrocement encased R.C. columns before and after fire exposure for different durations. The main thrust is on assessing the decrease in strength due to fire and stress-strain due to passive confinement of concrete by ferrocement mesh wires, both before and after fire exposure. Ferrocement encased R.C. columns are used for prefabrication, repair/retrofitting and for insitu columns. Presence of mesh reinforcement encased columns confines the core concrete, thereby increasing the strength and ductility. Research literature contains reports on both theoretical as wells as experimental investigations of such columns. However, the experimental investigations do not cover all parameters exhaustively. The purpose of this dissertation is to examine the effect of fire on deterioration ferrocement encased R.C. columns because a building may collapse or it may suffer serious damage. For this purpose 97 specimens of cylindrical and cubes were cast with different quantity of wire mesh. These were tested after exposure to fires of three different durations. Measurement of strength, deformation and pulse velocity were taken. The study has succeed in exhibiting the effect of quantity of bars and mesh on the residual strength and ductility after fire exposure.