Dynamic behaviour of a beam subjected to a force of time-dependent frequency (effects of solid viscosity and rotatory inertia)
With account taken of solid viscosity, through use of a Voigt-type mechanical model, the dynamic behaviour of a beam is investigated when the frequency of external forcing passes through the first critical frequency of the beam, increasing or decreasing. Rotatory inertia also is taken into account. Integrations involved in the theoretical results are carried out by Simpson's rule. From the results of the theoretical analysis, it is evident that the extreme values of the dynamic deflections decrease remarkably after they reach the maximum values, and that the effect of rotatory inertia on the maximum deflections is very small.