Design by testing of debonding load in RC elements strengthened with EBR FRP materials

This paper deals with the assessment of a design formulation to predict the end debonding load in reinforced concrete (RC) elements strengthened with externally bonded reinforcement (EBR) in fiber reinforced polymer (FRP). The debonding loads recorded during several bond tests have been collected and the reliability of three relationships furnished by literature and codes to calculate the end plate debonding load has been assessed. Then, the experimental data have been used to assess a new relationship for the end plate debonding load according to the ‘design by testing’ procedure suggested in European codes. In particular, numerical factors for calculating mean values and percentiles for the end plate debonding load have been calibrated. Moreover, different factors have been assessed for the preformed and cured in-situ EBR FRP systems that have been distinguished in order to better exploit the performance of the latter ones.