Civil Engineering Department, Aristotle University of Thessaloniki, Greece


In the present paper, an analytical micro-model able to simulate the behaviour of masonry panels under in-plane loading to failure is briefly presented. Bricks and mortar joints are modelled separately with 2-D finite elements. The model, although two-dimensional, is able to successfully predict the tri-axial stress state of bricks and mortar and includes non-linear tri-axial constitutive models and failure criteria for the materials as well as a failure criterion for the joints. Use of the model allows the diagnosis of various local types of material and joint damage as well as the simulation of the damage evolution to failure.
The paper proceeds with the calibration and evaluation of the analytical model based on the mechanical properties of the materials and masonry of an old building. These properties were experimentally determined as part of a research programme and were presented in an earlier paper. There follows an extrapolation of experimental results regarding shear strength of joints in small wailette specimens and strength of rectangular specimens under diagonal compressive loading based on a series of analyses of the corresponding models. Finally, an attempt is made to define analytically the masonry failure envelope (on – t) and to compare it with corresponding experimental results and theoretical models.