A. BACCI and V. LAUDAZI Accademia Navale, Livorno

A simple model is proposed able to evaluate the cyclic degradation of a masonry structure, based only on the measurement of the speed propagation of sonic waves. The masonry material is regarded as a porous, homogeneous, isotropic, elastic continuum, in which the concentration of voids is known and increases with the number of cycles. By applying classical results of fracture theory, the number of cycles of loading necessary to attain the collapse of the structure, and the influence of initial degree of damage or the subsequent resistance of the structure is estimated.