A cohesive contact algorithm to evaluate the mechanical behaviour of concrete ITZ at different roughness conditions

The capability of modelling damage evolution in concrete materials represents a topic of relevance for improving the design of concrete structures and for the recovery of existing components. The present work aims to investigate the collapsible behaviour of the Interfacial Transition Zone (ITZ) around coarse inclusions, by using a new cohesive contact law able to take into account the coupling between normal/peeling and shear stresses, specifically calibrated to take into account the roughness of various aggregate types. A series of numerical analyses have been carried out considering different material inclusions and distributions within concrete samples, so proving the capabilities of the proposed formulation.