Bond of FRP Laminates to Concrete
ACI Materials Journal, 98 (3):
256--264 (May 2001)Abstract
Fiber reinforced polymer (FRP) laminates are being successfully used
for strengthening of existing reinforced concrete structures. Bond
of the FRP reinforcement to the concrete substrate is of critical
importance for the effectiveness of the technique. In this project,
flexural test specimens were prepared to address some of the factors
expected to affect bond, namely, bonded length, concrete strength,
number of plies (stiffness), sheet width and, to a limited extent,
surface preparation. Results are presented and discussed in this
paper. A shear lag approach, along with a simple shear model for
the evaluation of the slip modulus, is used to model the strain distribution
at moderate load levels. Finally, expressions of the peeling load
and the effective bond length are presented. A design equation is
proposed to calculate the effective FRP ultimate strain to be used
in design to account for bond-controlled failure.