The
paper presents test results of full-size simply supported reinforced concrete
beams with rectangular cross
section, strengthened for flexure with NSM CFRP
strips. The specimens with differ entsteel and CFRP
reinforcement ratio were
tested under four point monotonic loading. The aim of the test was to obtain
the same flexural capacity for all tested beams. The structural performance and
modes of failure of the tested beams are presented and discussed in this paper.
Full composite action between the NSM CFRP strips and concrete was achieved.
Results of the test indicated that the lower was steel reinforcement ratio and
higher was CFRP ratio the lower was
stiffness and ultimate load of strengthened
beams. It was due to lower the axial stiffness EfAf of NSMR CFRP strips than the
stiffness of the steel reinforcement. If the elasticity modulus of NSMR strip
is similar to the steel, the stiffness and load capacity of beams will be
higher.