Nonlinear FE analysis of RC slabs strengthened with prestressed EB CFRP strips under high-cyclic fatigue loading

Abstract

A significant issue in structural health monitoring is identifying fatigue damage in concrete structures that have been retrofitted with externally bonded Carbon Fiber Reinforced Polymer (EB-CFRP). Although the finite element method has significantly contributed to modeling the damage mechanisms of concrete, reinforcement, and CFRP, further research is still needed in this area. For instance, RC slabs reinforced with EB-CFRP technology must be evaluated and predicted for high-cyclic fatigue and progressive damage. Therefore, this research aimed to develop intricate numerical models that could be utilized to analyze the dynamics of fatigued RC slabs and find damage in slabs that have prestressed EB-CFRP reinforcement. It was discovered that prestressed EB-CFRP-reinforced RC slabs can significantly affect the vibration response of specimens. When the prestressing and fatigue loads were high, the prestressing altered the damage distribution at the CFRP-concrete interface, leading to debonding of the CFRP near the ends of the RC slabs. Additionally, for high-cyclic fatigue progressive damage, the mixed damage mode—steel yielding and CFRP debonding—was the primary failure mechanism of RC slabs reinforced with prestressed EB-CFRP.