Finite element analysis of test specimens to assess composite-concrete bond durability

A modified double cantilever beam (MDCB)-hinged specimen that has been used to measure the toughness of the bond between concrete and composite overlays experimentally is modeled by finite element analysis to validate the equations used to analyze the results. Results show that the MDCB-hinged specimen gives good results for Mode I loading but not for Mode II loading. Therefore, a MDCB-tabbed specimen is proposed and evaluated. Equations for calculating the strain energy release rate of the new sample are proposed. Results show that the MDCB-tabbed specimen may be used to determine the Mode II strain energy release rate of the composite-to-concrete bond. In addition, several parameters that may affect the interface bond between the FRP overlay and the concrete are studied.