Numerical analysis of masonry structures via interface models Original Research Article

The present paper is devoted to the theoretical formulation and numerical implementation of an interface model suitable to simulate the behavior of mortar joints in masonry structures. The interface laws are formulated in the framework of elasto-plasticity for non-standard materials in order to simulate the softening response which occurs along the decohesion process in presence of shear and tension tractions. A variable material dilatancy parameter is introduced together with a further geometrical dilatancy related to the roughness of contact surfaces after joint fracture. An asperity model is adopted with the aim to describe the evolution of the contact surface shape during the loss of cohesion process and sliding. The interface laws are expressed both in rate and discrete incremental form. Details regarding the numerical implementation and the related algorithms are presented. Finally, the results obtained from the application to two case-studies show the capabilities of the proposed interface model and the effectiveness of the computational strategy herein presented.