Metodi perturbativi per lo studio delle vibrazioni flessionali di travi costituite da materiale non resistente a trazione

The thesis concerns the flexural nonlinear oscillations of rectangular cross-sectional masonry columns. A variational approach is proposed to obtain explicitly some approximated solutions by using the averaged Lagrangian of the system. The dynamic equilibrium of the beam is studied for some boundary conditions, for free dumped and undumped oscillations and in the case of primary resonance of the first mode. The peculiar behaviour of masonry, that is generally not able to withstand tensile stresses, is taken into account by means of a masonry - like constitutive equation.