Interface Model Applied to Fracture of Masonry Structures

The failure of unreinforced masonry structures subjected to lateral loads is dominated, to a large extent, by the fracture of mortar joints as well as the cracking and crushing of masonry units. This can be simulated by means of a finite element approach in which the mortar joints are modeled with interface elements and the masonry units are modeled with smeared crack elements. To this end, a dilatant interface constitutive model capable of simulating the initiation and propagation of interface fracture under combined normal and shear stresses in both tension-shear and compression-shear regions, and capable of simulating the experimentally observed dilatancy was developed in this study. The performance of the interface model in representing the behavior of masonry mortar joints is evaluated with the available experimental results. Furthermore, the failure of unreinforced concrete masonry panels is analyzed with the aforementioned approach. It is concluded that the numerical model is capable of predicting the response of a masonry assemblage based on the response of its basic constituents.