Response of Periodic Systems to a Moving Load

The motion of a beam or a plate resting on an elastic foundation and subjected to a moving load has been studied by numerous authors. But the extension of these studies to the case of periodic structures is difficult. In this paper, a method allowing the calculation at low numerical cost of periodically supported beams subjected to a moving force, is proposed. The interpretation of this method on the basis of the free-wave propagation equations in periodic structures has led to the definition of the predominant, so-called “primary,” critical speeds. Individual examples were used to test the method. It was also possible to define the limits of a Winkler continuous model in representing the support reactions.