1. EFFECT OF ELEVATED TEMPERATURE ON THE BOND STRENGTH OF
REINFORCED CONCRETE IN TENSION
Rauden B. Panotes, CE, MSSt - Mapua Institute of Technology
Abstract
This study investigates the effects of elevated temperature and material strength
degradation on the interconnecting bond of reinforcing steel bar after reinforced concrete was
exposed to elevated temperature and gradually cooled. Pull out and concrete cylindrical samples
were prepared and induced to 200-, 300-, and 500⁰C elevated temperatures. These were used to
evaluate the bond behavior and residual compressive strength, respectively. Moreover, empirical
models were formulated to describe and predict the probable behavior of bond strength and
compressive strength as concrete exposed to increasing heat temperature. The results showed
that heating caused significant losses in compressive and bond strength. The findings indicated
further that the heating had a more detrimental effect on bond strength than the compressive
strength of ordinary concrete. The sudden decrease of bond strength as compressive strength
reduced was evidently described by the high value of positive slope of the linear correlation
between residual compressive strength and bond strength.
Keywords: bond strength, residual compressive strength, elevated temperature.