Flexural strengthening of beams with large Opening in critical bending zone (static conditions)

This research study was conducted to investigate the flexural strengthening of concrete
beams with large opening using CFRP strips. The principal focus was given to
determine the effects of the circular and square shape of openings. The amount and
configuration of CFRP strips was determined based on the failure behaviour of the
corresponding beam without strengthening. The amount of opening (circular and square)
was kept as 8% - 10% of the beam elevation. The circular opening caused about 3.5%
load capacity loss as compared to the solid beam and square opening resulted in about
22% loss of capacity. After applying CFRP on the circular opening beam; the capacity
was obtained as 64% higher than the capacity of the solid beam. Whereas with square
openings; CFRP application increased the capacity by 14% with respect to the solid
beam. After applying CFRP on the circular opening beam; the capacity was obtained as
67% higher than the capacity of the circular opening beam without CFRP strips.
Whereas with square openings; CFRP application increased the capacity by 11% with
respect to the square opening beam without CFRP strips.