Theoretical and experimental identification of a non-linear beam

The identi"cation of the dynamic characteristics of linear systems is now widely used and interest in non-linear systems has increased. The objective of this paper is to demonstrate the performance of the restoring force surface method as far as the identi"cation of non-linear systems is concerned. The vibrations of a clamped beam are investigated for two di!erent kinds of non-linearity. Firstly, the beam shows a non-linear behaviour characterized by a piecewise linear sti!ness and secondly, the non-linearity comes from a bilinear sti!ness. Both numerical and experimental results are presented. (C) 2001 Academic Pres