Interface Elements for the Analysis of Masonry Structures

The present paper deals with the modeling of the mechanical behavior of masonry elements regarded as heterogeneous systems, made of mortar and bricks joined by means of interfaces. The adopted computational strategy consists of modeling the brick units, the mortar joints and the interfaces responsible for the mortar-brick decohesion mechanisms; to this end, a special interface model combining damage and friction is adopted. A numerical procedure, based on the backward Euler time-integration scheme, is introduced; the time step is solved adopting a displacement driven predictor-corrector algorithm. Some numerical applications are performed in order to assess the ability of the proposed model and algorithm in reproducing the nonlinear response of masonry elements. Finally, unreinforced and FRP-reinforced masonry arches, for which experimental results are available, are modeled and the mechanical response is investigated. The results obtained by the numerical model are put in comparison with the experimental ones, showing the ability of the proposed model to simulate the behavior of the unreinforced and reinforced masonry arches in term of ultimate load, nonlinear behavior and collapse mechanism.