Fracture performance of GFRP-RC beams with working cracks in alkaline environment for eight years

The development trend of glass fiber-reinforced polymer-reinforced concrete (GFRP-RC) beams partially or entirely replacing reinforced concrete beams has gained acceptance. However, related research on long-term fracture durability is insufficient. This paper aims to investigate the long-term fracture durability of GFRP-RC beams, 36 GFRP-RC beams under the alkaline corrosion environment and sustained load for eight years were subjected to three-point eccentric loading experiments. The load crack opening distance (P-CMOD) curve and the corresponding fracture energy were obtained. The results show that the bearing capacity and residual fracture energy retention (ER) of GFRP-RC beams with working cracks in the APS (alkaline + pre-cracks + sustained load) group were 18.71% and 26.38% lower, respectively than those in the AS (alkaline + sustained load) group. After analyzing the critical CMOD curves for each service period with failure probabilities of 60% and 85%, a long-term crack growth failure probability model for the service time t and the critical CMOD was proposed, which provide a non-destructive damage assessment method for GFRP-RC beams in actual service. (c) 2021 Published by Elsevier Ltd.