Experimental campaign on dapped-end beams with different reinforcement layouts

Reinforced Concrete (RC) discontinuity regions (D-regions), such as half-joints, can represent vulnerable zones in existing RC bridges since they can exhibit a brittle failure mechanism. In common design practice, the ultimate strength of D-regions is assessed through Strut and Tie (S&T) models. Current structural design codes, like Eurocode 2, identify two resistant mechanisms for half-joints with concentrated rebars but do not provide information about the identification of steel bars involved in the resistant mechanism in the case of distributed reinforcement, which is typical of existing half-joints. To fill this gap, an experimental campaign on half-joints with different reinforcement layouts has been carried out at the Structural and Materials Testing Laboratory of the Department of Civil and Environmental Engineering of Florence. Experimental results show the influence of the reinforcement layout on the post-peak response of dapped ends and can be used in future research for accurately identifying the steel bars involved in the resistant mechanism of dapped ends, especially in the presence of distributed reinforcement.