INTERFACIAL DELAMINATION FAILURE IN BONDED CONCRETE OVERLAY SYSTEMS - A REVIEW OF THEORIES AND MODELLING METHODS

This study reviews the theories and modelling methods for describing interfacial delamination failure process between two bonded cementitious materials. Complex interfacial stress conditions at discontinuities and areas of high stress concentrations were primary areas of concern. Distinct analytical cases involving intrinsic material and structural property variables were considered. An approach based on plane strain analysis within the context of Interface Cohesive Zone Model (ICZM) was cited and presented as viable for describing and predicting delamination mode of failure in bonded concrete overlays systems (BCOs). The study shows that the use of numerical computational tools is vital in resolving the manifold complexity associated with interfacial delamination problems. In the concluding analytical model, it is evident that the numerical values of the delamination failure coefficient(D) and the corresponding Mixed-Mode energy release rates (G) vary depending on the overlay structural scale, the type of problem (plane stress or plane strain) and the degree of mismatched properties between the overlay and the substrate