Evaluation of Bond Strength in Concrete Elements Externally Reinforced with CFRP Sheets and Anchoring Devices

Use of anchoring devices can be useful to avoid or delay end debonding failure in reinforced concrete elements externally bonded with fiber-reinforced plastic materials. Many theoretical formulations are now available to predict bond strength, but no design provisions have been suggested to take into account the beneficial effect of anchorage devices. This paper presents the results of experimental bond tests performed on concrete blocks externally strengthened with carbon fiber sheets. The prime focus is the evaluation of effect given by three different types of anchorage systems upon increasing debonding load. A simple model is introduced to predict the influence of the examined anchorage systems on the debonding load. Its accuracy is confirmed by comparisons with the experimental results.