Evaluation of Bond Strength of FRP Reinforcing Rods in Concrete and FE Modelling

摘要

The bond behavior of FRP rebars embedded in concrete was studied. A total of forty-eight pull-out specimens were tested. The effects of different parameters of FRP rebars, such as type, shape and diameter, on the bond behavior of FRP rebars and concrete were evaluated. The average bond strength developed by the Aramid, Carbon and Glass FRP bars in pull-out tests was experimentally evaluated. Test results indicated that the average maximum bond strength of FRP rebars varied from 7.6 to 28 MPa depending on surface deformation and diameter. The maximum bond strength of FRP bars to concrete was 28 MPa, which was obtained from sand-coated bars (ISOROD bars). The M-Bar smooth type had the lowest bond behavior in concrete. The surface deformation and type of risen (the mechanical and physical properties of the outer surface) are the characteristics that have the greatest effect on the bond behavior of FRP rebars in concrete. Unlike steel bars, the mode of failure was damage of the outer surface of FRP rebars. Theoretical analyses using the finite element method were conducted to study the effect of FRP rebar type, bonded length and surface characteristics of the FRP bars. The finite element simulation is in good agreement with the experimental results of the pull-out tests obtained from carbon ISOROD bars.