Bond between Ultra High‐Performance Fiber Reinforced Concrete and existing concrete: a review

Abstract The application of Ultra High‐Performance Fiber Reinforced Concrete (UHPFRC) is increasing worldwide to repair and strengthen existing structures. One the main applications in bridge components, e.g., decks piers, but also floors residential or industrial buildings realize construction joints prefabricated members. To properly design a strengthening intervention with UHPFRC, bond between structure new layer reinforcing material should be developed. In this work, review about interface behavior UHPFRC concrete carried out, analyzing detail available test methods, variables influencing two materials. Among them, role moisture exchanges, properties concrete, surface roughness, effect bonding agents are discussed detail. This work shows only proper treatments can enhance strength, otherwise they could detrimental. most previous experiences, efficiently substrate, resulting composites that behaves monolithically.