ALESSANDRO BARATTA University of Naples “Federico II”

A mechanical model for masonry structures is introduced which assumes that masonry can be idealized as a particular kind of “Not-resisting-tension” (NRT) material. The expected agreement of the model with the real behaviour of masonry buildings is discussed. In this approach, it is assumed that actual masonry may be endowed with a small degree of tensile strength, but that it exhibits brittle rupture under tension stresses. It is proved that the NRT material model approximates actual stresses, in the sense of complementary energy. Application to structural analysis of portal-arch structures is presented in detail.