Volume 3, Issue 1 (January 2006)
Surface Roughness, Quasi-Static Fracture, and Cyclic Fatigue Effects on GFRP- and CFRP-Concrete Bonded Interfaces
The recently developed experimental fracture approach known as the Single Contoured-Cantilever Beam (SCCB) was used to characterize the interface bonds between concrete substrates and two varieties of FRP: glass and carbon (abbreviated GFRP and CFRP, respectively). Limited research has been performed concerning the FRP-concrete interface bond relative to three surface-roughness grades: low- (<10 μm), moderate- (≈ 10–50 μm), and high- (>50 μm), to establish the optimal formation for bonding. By use of the SCCB approach, Mode I critical strain energy release rate results are measured and quantified. Finally, considering that a majority of externally strengthened FRP concrete structures involves bridges and girders that are subjected to repeated (as opposed to static) loads, a preliminary study is conducted on cyclically fatigued FRP-concrete interfaces under varying load-ratio and frequency effects.