Thin bonded overlays - About the role of fiber reinforcement on the limitation of their debonding

This paper concerns metal fiber-reinforced repairs and toppings of slabs or concrete pavements. The durability of thin bonded overlays (less than 100-mm thick) depends upon the durability of their bond to the base slab onto which they have been applied. This paper focuses on the improved bond durability of fiber-reinforced overlays. Because fiber reinforcements at usual dosages have no significant effect on either the changes of length of the overlays or on the shear strength of their bond to the base, another cause of this better durability was sought. The research demonstrates, by finite elements computation and experimental verification, that the debonding of overlays is caused, in large, by the coupled effects of vertical cracking through the overlay and traffic loads. It is by restraining cracking that fibers enhance the bonding durability of overlays.