Externally-applied
circumferential FRP wraps have proven to be an efficient and effective
technique to repair
and strengthen structurally deficient
reinforced concrete
columns. Guidelines for the design of FRP-wrapped concrete members are
currently available and field applications of this technique have been
implemented around the world. However, two specific and related issues that
require research attention are eccentric loading and
slenderness effects on
FRP-wrapped concrete columns. To date, the vast majority of tests on
FRP-confined concrete have been performed on short, un-reinforced, small-scale
concrete cylinders with height-to-diameter ratios of less than 3, and tested
under concentric, monotonic axial load. These tests have been useful as a means
of accurately characterizing the stress-strain behaviour of FRP-confined
concrete such that it is now reasonably well understood. In practice however,
most columns are subjected to eccentric loads and have considerably larger
height-to-diameter ratios. The potential for increased susceptibility of
FRP-wrapped columns to slenderness effects has received relatively little research
attention, both for columns that become slender as a consequence of wrapping
and increased service loads, and for strengthening of pre-existing slender
members. This paper presents the results of an experimental program to
investigate the effects of slenderness on FRP-wrapped circular reinforced
concrete columns.