RC beams strengthened with EB FRP sheets were found to
increase significantly their stiffness and load capacity, but
decrease their ductility and often result in brittle failure
modes. Delamination of FRP-plate due to the shear stress
concentration at the end of the bonded plate was also the
common failure mode for RC beams strengthened with EB
FRP [2]. On the other hand, the premature debonding of the
FRP was found to be the main drawback of using EB
technique in strengthening. Studies by Ashour et al. (2004), as
in [7] noted that brittle peeling failure of the concrete cover
adjacent to the CFRP sheets was the dominant failure mode of
the strengthened beam with EB CFRP sheets. Increasing the
CFRP sheet length to cover the entire negative and positive
moment zones did not prevent peeling failure of the CFRP
laminate and was found to be effective when tensile rupture of
the CFRP sheets was the failure mode. NSM technique is one
solution to overcome of the debonding of the EB CFRP sheets.
Meanwhile, De Lorenzis and Nanni (2001), as in [4] identified
two common failure modes of RC beams strengthened with