CHAPTER 10—FLEXURAL STRENGTHENING
Bonding FRP reinforcement to the tension face of a concrete flexural member with fibers oriented along the length of the member will provide an increase in flexural strength. Increases in overall flexural strength from 10 to 160% have been documented (Meier and Kaiser 1991 ; Ritchie et al. 1991; Sharif et al. 1994). When taking into account the strengthening limits of Section 9.2 and ductility and serviceability limits, however, strength increases of up to 40% are more reasonable.
This chapter does not apply to FRP systems used to enhance the flexural strength of members in the expected plastic hinge regions of ductile moment frames resisting seismic loads. The design of such applications, if used, should examine the behavior of the strengthened frame, considering that the strengthened sections have muchreduced rotation and curvature capacities. In this case, the effect of cyclic load reversal on the FRP reinforcement should be investigated.