Shrinkage induced edge curling and debonding in slab elements reinforced with bonded overlays: Influence of fibers and SRA

An increase of infrastructures needing repair and rehabilitation has led to a growing use of bonded overlays to members such as slabs, columns, bridge decks, bridge piers, etc. These overlays are nowadays made of High Performance Concrete (HPC) able to significantly increase the structural performance with a smaller thickness. However, HPC is generally characterized by a higher percentage of cement paste that increases shrinkage phenomena. Therefore, despite the many advantages, the performance of overlays is usually affected by debonding (from the original surface) and/or early age cracking.