Failure
of a structural element under diagonal compression is brittle in nature and
could compromise the structure
ductility in seismic design. In many cases,
strengthening using FRP Jackets might be the optimum solution to prevent such
failures. A
procedure for calculating the thickness of the FRP jacket required
to resist combined shear and torsion is proposed. The proposed procedure was
used to calculate the FRP thickness required for the strengthening of three
T-girders subjected to combined shear and torsion. The girders were constructed
and tested using a test setup designed to subject the specimen to combined
shear and torsion with relatively low moment up to failure. Three strengthening
techniques namely; U-jacket, extended U-jacket and full jacket were implemented
using ± 45° carbon fiber reinforced polymers (CFRP). The theoretical
predications were compared to the experimental results. The procedure was found
to provide reasonable conservative estimates.