In this study, FRP strengthened concrete specimens were submitted to accelerated ageing conditions (40°C and 95% R.H.) and the time evolution of the adhesive strength was monitored using either the pull-off test or a single lap shear test. On the other hand, microstructural evolutions of the polymer adhesive due to hydrothermal ageing were investigated by DSC analyses (differential scanning calorimetry) and tensile tests. On the basis of these results, effects of accelerated ageing on the adhesive bond properties are discussed, and the influence of the testing method (pull-of and shear tests) on observed evolutions is also considered.
