Composite
steel-concrete girders are used widely in bridge and building construction as
the main structural elements
in flexure. The load-carrying capacity of an
under-strength or deficient steel-concrete composite girders can be improved by
epoxy bonding fiber reinforced polymers (FRP) laminates to its tension flange.
This paper presents the results of an experimental study that investigated the
behaviour of steel-concrete composite girders strengthened in flexure using
various advanced composite materials tested under static loading. The different
strengthening materials used in this investigation included
unidirectional intermediate and high modulus Carbon Fiber Reinforced Polymer (CFRP) plates,
unidirectional CFRP sheets and the newly developed unidirectional Steel
Reinforced Polymer (SRP) sheets. The primary objective of this investigation
was to assess the flexural behaviour of the strengthened beams and examine the
effectiveness of the different strengthening materials. Test results are very
promising and showed that epoxy bonded CFRP sheets or plates and SRP sheets
significantly improved the stiffness and increased the ultimate load carrying
capacity of the steel-concrete composite girders. The effect of strengthening
on the elastic stiffness and ultimate strength was more profound for beam with
high modulus CFRP plate.